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freebsd-skq/sys/vm/uma_core.c

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/* -> /*- for license, minor formatting changes
2005-01-07 02:29:27 +00:00
/*-
sys: general adoption of SPDX licensing ID tags. Mainly focus on files that use BSD 2-Clause license, however the tool I was using misidentified many licenses so this was mostly a manual - error prone - task. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts. No functional change intended.
2017-11-27 15:23:17 +00:00
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
* Copyright (c) 2002-2005, 2009, 2013 Jeffrey Roberson <jeff@FreeBSD.org>
Improve canonicalization of copyrights. Order copyrights by order of assertion (jeff, bmilekic, rwatson). Suggested ages ago by: bde MFC after: 1 week
2005-07-16 09:51:52 +00:00
* Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
Better align output of "show uma" by moving from displaying the basic counters of allocs/frees/use for each zone to the same statistics shown by userspace "vmstat -z". MFC after: 3 days
2006-10-26 12:55:32 +00:00
* Copyright (c) 2004-2006 Robert N. M. Watson
Improve canonicalization of copyrights. Order copyrights by order of assertion (jeff, bmilekic, rwatson). Suggested ages ago by: bde MFC after: 1 week
2005-07-16 09:51:52 +00:00
* All rights reserved.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* uma_core.c Implementation of the Universal Memory allocator
*
* This allocator is intended to replace the multitude of similar object caches
* in the standard FreeBSD kernel. The intent is to be flexible as well as
sys/vm: minor spelling fixes in comments. No functional change.
2016-05-02 20:16:29 +00:00
* efficient. A primary design goal is to return unused memory to the rest of
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* the system. This will make the system as a whole more flexible due to the
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* ability to move memory to subsystems which most need it instead of leaving
* pools of reserved memory unused.
*
* The basic ideas stem from similar slab/zone based allocators whose algorithms
* are well known.
*
*/
/*
* TODO:
* - Improve memory usage for large allocations
* - Investigate cache size adjustments
*/
Use __FBSDID().
2003-06-11 23:50:51 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
#include "opt_ddb.h"
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include "opt_param.h"
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
#include "opt_vm.h"
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include <sys/param.h>
#include <sys/systm.h>
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
#include <sys/bitset.h>
call vm_lowmem hook in uma_reclaim_worker A comment near kmem_reclaim() implies that we already did that. Calling the hook is useful, because some handlers, e.g. ARC, might be able to release significant amounts of KVA. Now that we have more than one place where vm_lowmem hook is called, use this change as an opportunity to introduce flags that describe a reason for calling the hook. No handler makes use of the flags yet. Reviewed by: markj, kib MFC after: 1 week Sponsored by: Panzura Differential Revision: https://reviews.freebsd.org/D9764
2017-02-25 16:39:21 +00:00
#include <sys/eventhandler.h>
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/malloc.h>
Generate KTR trace records for uma_zalloc_arg() and uma_zfree_arg(). This doesn't trace every event of interest in UMA, but provides enough basic information to explain lock traces and sleep patterns.
2004-08-06 21:52:38 +00:00
#include <sys/ktr.h>
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include <sys/lock.h>
#include <sys/sysctl.h>
#include <sys/mutex.h>
In uma_zalloc_arg(), if we are performing a M_WAITOK allocation, ensure that td_intr_nesting_level is 0 (like malloc() does). Since malloc() calls uma we can probably remove the check in malloc() for this now. Also, perform an extra witness check in that case to make sure we don't hold any locks when performing a M_WAITOK allocation.
2002-05-20 17:54:48 +00:00
#include <sys/proc.h>
This is the much-discussed major upgrade to the random(4) device, known to you all as /dev/random. This code has had an extensive rewrite and a good series of reviews, both by the author and other parties. This means a lot of code has been simplified. Pluggable structures for high-rate entropy generators are available, and it is most definitely not the case that /dev/random can be driven by only a hardware souce any more. This has been designed out of the device. Hardware sources are stirred into the CSPRNG (Yarrow, Fortuna) like any other entropy source. Pluggable modules may be written by third parties for additional sources. The harvesting structures and consequently the locking have been simplified. Entropy harvesting is done in a more general way (the documentation for this will follow). There is some GREAT entropy to be had in the UMA allocator, but it is disabled for now as messing with that is likely to annoy many people. The venerable (but effective) Yarrow algorithm, which is no longer supported by its authors now has an alternative, Fortuna. For now, Yarrow is retained as the default algorithm, but this may be changed using a kernel option. It is intended to make Fortuna the default algorithm for 11.0. Interested parties are encouraged to read ISBN 978-0-470-47424-2 "Cryptography Engineering" By Ferguson, Schneier and Kohno for Fortuna's gory details. Heck, read it anyway. Many thanks to Arthur Mesh who did early grunt work, and who got caught in the crossfire rather more than he deserved to. My thanks also to folks who helped me thresh this out on whiteboards and in the odd "Hallway track", or otherwise. My Nomex pants are on. Let the feedback commence! Reviewed by: trasz,des(partial),imp(partial?),rwatson(partial?) Approved by: so(des)
2014-10-30 21:21:53 +00:00
#include <sys/random.h>
Switch vm_object lock to be a rwlock. * VM_OBJECT_LOCK and VM_OBJECT_UNLOCK are mapped to write operations * VM_OBJECT_SLEEP() is introduced as a general purpose primitve to get a sleep operation using a VM_OBJECT_LOCK() as protection * The approach must bear with vm_pager.h namespace pollution so many files require including directly rwlock.h
2013-02-20 10:38:34 +00:00
#include <sys/rwlock.h>
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
#include <sys/sbuf.h>
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
#include <sys/sched.h>
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include <sys/smp.h>
Redo r292484. Embed task(9) into zone, so that uz_maxaction is called in a context that can sleep, allowing consumers of the KPI to run their drain routines without any extra measures. Discussed with: jtl
2016-02-03 23:30:17 +00:00
#include <sys/taskqueue.h>
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
#include <sys/vmmeter.h>
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
MFC
2013-02-26 23:52:23 +00:00
#include <vm/vm_pageout.h>
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#include <vm/vm_param.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
#include <vm/uma.h>
#include <vm/uma_int.h>
Remove the temporary alignment check in free(). Implement the following checks on freed memory in the bucket path: - Slab membership - Alignment - Duplicate free This previously was only done if we skipped the buckets. This code will slow down INVARIANTS a bit, but it is smp safe. The checks were moved out of the normal path and into hooks supplied in uma_dbg.
2002-05-02 02:08:48 +00:00
#include <vm/uma_dbg.h>
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
#include <ddb/ddb.h>
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
#ifdef DEBUG_MEMGUARD
#include <vm/memguard.h>
#endif
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
* This is the zone and keg from which all zones are spawned. The idea is that
* even the zone & keg heads are allocated from the allocator, so we use the
* bss section to bootstrap us.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
static struct uma_keg masterkeg;
static struct uma_zone masterzone_k;
static struct uma_zone masterzone_z;
static uma_zone_t kegs = &masterzone_k;
static uma_zone_t zones = &masterzone_z;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* This is the zone from which all of uma_slab_t's are allocated. */
static uma_zone_t slabzone;
/*
* The initial hash tables come out of this zone so they can be allocated
* prior to malloc coming up.
*/
static uma_zone_t hashzone;
Add uma_set_align() interface, which will be called at most once during boot by MD code to indicated detected alignment preference. Rather than cache alignment being encoded in UMA consumers by defining a global alignment value of (16 - 1) in UMA_ALIGN_CACHE, UMA_ALIGN_CACHE is now a special value (-1) that causes UMA to look at registered alignment. If no preferred alignment has been selected by MD code, a default alignment of (16 - 1) will be used. Currently, no hardware platforms specify alignment; architecture maintainers will need to modify MD startup code to specify an alignment if desired. This must occur before initialization of UMA so that all UMA zones pick up the requested alignment. Reviewed by: jeff, alc Submitted by: attilio
2007-02-11 20:13:52 +00:00
/* The boot-time adjusted value for cache line alignment. */
- Merge changes to the base system to support OFED. These include a wider arg2 for sysctl, updates to vlan code, IFT_INFINIBAND, and other miscellaneous small features.
2011-03-21 09:40:01 +00:00
int uma_align_cache = 64 - 1;
Add uma_set_align() interface, which will be called at most once during boot by MD code to indicated detected alignment preference. Rather than cache alignment being encoded in UMA consumers by defining a global alignment value of (16 - 1) in UMA_ALIGN_CACHE, UMA_ALIGN_CACHE is now a special value (-1) that causes UMA to look at registered alignment. If no preferred alignment has been selected by MD code, a default alignment of (16 - 1) will be used. Currently, no hardware platforms specify alignment; architecture maintainers will need to modify MD startup code to specify an alignment if desired. This must occur before initialization of UMA so that all UMA zones pick up the requested alignment. Reviewed by: jeff, alc Submitted by: attilio
2007-02-11 20:13:52 +00:00
- Don't abuse M_DEVBUF, define a tag for UMA hashes.
2003-09-19 07:23:50 +00:00
static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
/*
* Are we allowed to allocate buckets?
*/
static int bucketdisable = 1;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/* Linked list of all kegs in the system */
(S)LIST_HEAD_INITIALIZER takes a (S)LIST_HEAD as an argument. Fix some wrong usages. Note: this does not affect generated binaries as this argument is not used. PR: 137213 Submitted by: Eygene Ryabinkin (initial version) MFC after: 1 month
2009-12-28 22:56:30 +00:00
static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Add bucket size column to `show uma` DDB command. - Add `show umacache` command to show alike stats for cache-only UMA zones.
2013-11-28 19:20:49 +00:00
/* Linked list of all cache-only zones in the system */
static LIST_HEAD(,uma_zone) uma_cachezones =
LIST_HEAD_INITIALIZER(uma_cachezones);
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
/* This RW lock protects the keg list */
Start annotating global _padalign locks with __exclusive_cache_line While these locks are guarnteed to not share their respective cache lines, their current placement leaves unnecessary holes in lines which preceeded them. For instance the annotation of vm_page_queue_free_mtx allows 2 neighbour cachelines (previously separate by the lock) to be collapsed into 1. The annotation is only effective on architectures which have it implemented in their linker script (currently only amd64). Thus locks are not converted to their not-padaligned variants as to not affect the rest. MFC after: 1 week
2017-09-06 20:28:18 +00:00
static struct rwlock_padalign __exclusive_cache_line uma_rwlock;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Simplify boot pages management in UMA. It is simply a contigous virtual memory pointer and number of pages. There is no need to build a linked list here. Just increment pointer and decrement counter. The only functional difference to old allocator is that before we gave pages from topmost and down to lowest, and now we give them in normal ascending order. While here remove padalign from a mutex that is unused at runtime. Reviewed by: alc
2017-06-01 18:26:57 +00:00
/*
* Pointer and counter to pool of pages, that is preallocated at
* startup to bootstrap UMA. Early zones continue to use the pool
* until it is depleted, so allocations may happen after boot, thus
* we need a mutex to protect it.
*/
static char *bootmem;
static int boot_pages;
static struct mtx uma_boot_pages_mtx;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
static struct sx uma_drain_lock;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* Is the VM done starting up? */
static int booted = 0;
1. Prior to r214782, UMA did not support multipage allocations before uma_startup2() was called. Thus, setting the variable "booted" to true in uma_startup() was ok on machines with UMA_MD_SMALL_ALLOC defined, because any allocations made after uma_startup() but before uma_startup2() could be satisfied by uma_small_alloc(). Now, however, some multipage allocations are necessary before uma_startup2() just to allocate zone structures on machines with a large number of processors. Thus, a Boolean can no longer effectively describe the state of the UMA allocator. Instead, make "booted" have three values to describe how far initialization has progressed. This allows multipage allocations to continue using startup_alloc() until uma_startup2(), but single-page allocations may begin using uma_small_alloc() after uma_startup(). 2. With the aforementioned change, only a modest increase in boot pages is necessary to boot UMA on a large number of processors. 3. Retire UMA_MD_SMALL_ALLOC_NEEDS_VM. It has only been used between r182028 and r204128. Reviewed by: attilio [1], nwhitehorn [3] Tested by: sbruno
2011-05-21 17:43:43 +00:00
#define UMA_STARTUP 1
#define UMA_STARTUP2 2
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
/*
* This is the handle used to schedule events that need to happen
* outside of the allocation fast path.
*/
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
static struct callout uma_callout;
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
#define UMA_TIMEOUT 20 /* Seconds for callout interval. */
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* This structure is passed as the zone ctor arg so that I don't have to create
* a special allocation function just for zones.
*/
struct uma_zctor_args {
Const-ify the zone name argument to uma_zcreate(9). MFC after: 3 days
2012-10-26 17:51:05 +00:00
const char *name;
- Changed the size element of uma_zctor_args to be size_t instead of int. - Changed uma_zcreate to accept the size argument as a size_t intead of int. Approved by: jeff
2002-05-02 07:36:30 +00:00
size_t size;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
uma_ctor ctor;
uma_dtor dtor;
uma_init uminit;
uma_fini fini;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
uma_import import;
uma_release release;
void *arg;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
int align;
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint32_t flags;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
};
struct uma_kctor_args {
uma_zone_t zone;
size_t size;
uma_init uminit;
uma_fini fini;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
int align;
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint32_t flags;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
};
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
struct uma_bucket_zone {
uma_zone_t ubz_zone;
char *ubz_name;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
int ubz_entries; /* Number of items it can hold. */
int ubz_maxsize; /* Maximum allocation size per-item. */
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
};
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* Compute the actual number of bucket entries to pack them in power
* of two sizes for more efficient space utilization.
*/
#define BUCKET_SIZE(n) \
(((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
Introduce new "256 Bucket" zone to split requests and reduce congestion on "128 Bucket" zone lock. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2014-06-12 11:57:07 +00:00
#define BUCKET_MAX BUCKET_SIZE(256)
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
struct uma_bucket_zone bucket_zones[] = {
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
{ NULL, "4 Bucket", BUCKET_SIZE(4), 4096 },
Add two new UMA bucket zones to store 3 and 9 items per bucket. These new buckets make bucket size self-tuning more soft and precise. Without them there are buckets for 1, 5, 13, 29, ... items. While at bigger sizes difference about 2x is fine, at smallest ones it is 5x and 2.6x respectively. New buckets make that line look like 1, 3, 5, 9, 13, 29, reducing jumps between steps, making algorithm work softer, allocating and freeing memory in better fitting chunks. Otherwise there is quite a big gap between allocating 128K and 5x128K of RAM at once.
2013-11-19 10:10:44 +00:00
{ NULL, "6 Bucket", BUCKET_SIZE(6), 3072 },
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
{ NULL, "8 Bucket", BUCKET_SIZE(8), 2048 },
Add two new UMA bucket zones to store 3 and 9 items per bucket. These new buckets make bucket size self-tuning more soft and precise. Without them there are buckets for 1, 5, 13, 29, ... items. While at bigger sizes difference about 2x is fine, at smallest ones it is 5x and 2.6x respectively. New buckets make that line look like 1, 3, 5, 9, 13, 29, reducing jumps between steps, making algorithm work softer, allocating and freeing memory in better fitting chunks. Otherwise there is quite a big gap between allocating 128K and 5x128K of RAM at once.
2013-11-19 10:10:44 +00:00
{ NULL, "12 Bucket", BUCKET_SIZE(12), 1536 },
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
{ NULL, "16 Bucket", BUCKET_SIZE(16), 1024 },
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
{ NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
{ NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
{ NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
Introduce new "256 Bucket" zone to split requests and reduce congestion on "128 Bucket" zone lock. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2014-06-12 11:57:07 +00:00
{ NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
{ NULL, NULL, 0}
};
Track UMA(9) allocation failures by zone, and export via sysctl. Requested by: victor cruceru <victor dot cruceru at gmail dot com> MFC after: 1 week
2005-07-15 23:34:39 +00:00
/*
* Flags and enumerations to be passed to internal functions.
*/
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
enum zfreeskip { SKIP_NONE = 0, SKIP_DTOR, SKIP_FINI };
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* Prototypes.. */
Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM. Note to self: When this is MFCed, sparc64 needs the same fix. Differential revision: https://reviews.freebsd.org/D2106 Reviewed by: kib Reported by: Michael Fuckner <michael@fuckner.net> Tested by: Michael Fuckner <michael@fuckner.net> MFC after: 2 weeks
2015-04-01 12:42:26 +00:00
static void *noobj_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
static void *page_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
static void *startup_alloc(uma_zone_t, vm_size_t, uint8_t *, int);
static void page_free(void *, vm_size_t, uint8_t);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int);
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
static void cache_drain(uma_zone_t);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
static void bucket_drain(uma_zone_t, uma_bucket_t);
- Fix a problem where we did not drain the cache of buckets in the zone when uma_reclaim() was called. This was introduced when the zone working-set algorithm was removed in favor of using the per cpu caches as the working set.
2004-02-01 06:15:17 +00:00
static void bucket_cache_drain(uma_zone_t zone);
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
static int keg_ctor(void *, int, void *, int);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
static void keg_dtor(void *, int, void *);
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
static int zone_ctor(void *, int, void *, int);
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
static void zone_dtor(void *, int, void *);
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
static int zero_init(void *, int, int);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void keg_small_init(uma_keg_t keg);
static void keg_large_init(uma_keg_t keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
static void zone_foreach(void (*zfunc)(uma_zone_t));
static void zone_timeout(uma_zone_t zone);
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
static int hash_alloc(struct uma_hash *);
static int hash_expand(struct uma_hash *, struct uma_hash *);
static void hash_free(struct uma_hash *hash);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
static void uma_timeout(void *);
static void uma_startup3(void);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void *zone_alloc_item(uma_zone_t, void *, int);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
static void bucket_enable(void);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
static void bucket_init(void);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
static void bucket_zone_drain(void);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
static uma_bucket_t zone_alloc_bucket(uma_zone_t zone, void *, int flags);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static uma_slab_t zone_fetch_slab(uma_zone_t zone, uma_keg_t last, int flags);
static uma_slab_t zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int flags);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
static void slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uma_fini fini, int align, uint32_t flags);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
static int zone_import(uma_zone_t zone, void **bucket, int max, int flags);
static void zone_release(uma_zone_t zone, void **bucket, int cnt);
Make M_ZERO flag work correctly on UMA_ZONE_PCPU zones. Sponsored by: Nginx, Inc.
2014-02-10 19:48:26 +00:00
static void uma_zero_item(void *item, uma_zone_t zone);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
void uma_print_zone(uma_zone_t);
void uma_print_stats(void);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Move uma_dbg_alloc() and uma_dbg_free() into uma_core.c, which allows to make uma_dbg.h not depend on uma_int.h, which allows to uninclude uma_int.h from the mbuf(9) allocator.
2016-02-03 22:02:36 +00:00
#ifdef INVARIANTS
static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
#endif
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLTYPE_INT,
0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
static int zone_warnings = 1;
Pull in r267961 and r267973 again. Fix for issues reported will follow.
2014-06-28 03:56:17 +00:00
SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
"Warn when UMA zones becomes full");
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
/*
* This routine checks to see whether or not it's safe to enable buckets.
*/
static void
bucket_enable(void)
{
Tweak condition for disabling allocation from per-CPU buckets in low memory situation. I've observed a situation where per-CPU allocations were disabled while there were enough free cached pages. Basically, cnt.v_free_count was sitting stable at a value lower than cnt.v_free_min and that caused massive performance drop. Reviewed by: alc MFC after: 1 week
2012-05-23 18:56:29 +00:00
bucketdisable = vm_page_count_min();
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
}
Abstract the logic to look up the uma_bucket_zone given a desired number of entries into bucket_zone_lookup(), which helps make more clear the logic of consumers of bucket zones. Annotate the behavior of bucket_init() with a comment indicating how the various data structures, including the bucket lookup tables, are initialized.
2004-11-06 11:43:30 +00:00
/*
* Initialize bucket_zones, the array of zones of buckets of various sizes.
*
* For each zone, calculate the memory required for each bucket, consisting
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
* of the header and an array of pointers.
Abstract the logic to look up the uma_bucket_zone given a desired number of entries into bucket_zone_lookup(), which helps make more clear the logic of consumers of bucket zones. Annotate the behavior of bucket_init() with a comment indicating how the various data structures, including the bucket lookup tables, are initialized.
2004-11-06 11:43:30 +00:00
*/
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
static void
bucket_init(void)
{
struct uma_bucket_zone *ubz;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
int size;
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
Eliminate an unused variable. MFC after: 1 week
2015-04-20 16:48:21 +00:00
for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
size = roundup(sizeof(struct uma_bucket), sizeof(void *));
size += sizeof(void *) * ubz->ubz_entries;
ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
}
}
Abstract the logic to look up the uma_bucket_zone given a desired number of entries into bucket_zone_lookup(), which helps make more clear the logic of consumers of bucket zones. Annotate the behavior of bucket_init() with a comment indicating how the various data structures, including the bucket lookup tables, are initialized.
2004-11-06 11:43:30 +00:00
/*
* Given a desired number of entries for a bucket, return the zone from which
* to allocate the bucket.
*/
static struct uma_bucket_zone *
bucket_zone_lookup(int entries)
{
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
struct uma_bucket_zone *ubz;
Abstract the logic to look up the uma_bucket_zone given a desired number of entries into bucket_zone_lookup(), which helps make more clear the logic of consumers of bucket zones. Annotate the behavior of bucket_init() with a comment indicating how the various data structures, including the bucket lookup tables, are initialized.
2004-11-06 11:43:30 +00:00
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
if (ubz->ubz_entries >= entries)
return (ubz);
ubz--;
return (ubz);
}
static int
bucket_select(int size)
{
struct uma_bucket_zone *ubz;
ubz = &bucket_zones[0];
if (size > ubz->ubz_maxsize)
return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
for (; ubz->ubz_entries != 0; ubz++)
if (ubz->ubz_maxsize < size)
break;
ubz--;
return (ubz->ubz_entries);
Abstract the logic to look up the uma_bucket_zone given a desired number of entries into bucket_zone_lookup(), which helps make more clear the logic of consumers of bucket zones. Annotate the behavior of bucket_init() with a comment indicating how the various data structures, including the bucket lookup tables, are initialized.
2004-11-06 11:43:30 +00:00
}
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
static uma_bucket_t
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_alloc(uma_zone_t zone, void *udata, int flags)
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
{
struct uma_bucket_zone *ubz;
uma_bucket_t bucket;
/*
* This is to stop us from allocating per cpu buckets while we're
As alc pointed out to me, vm_page.c 1.305 was incomplete: uma_startup() still uses the constant UMA_BOOT_PAGES. Change it to accept boot_pages as an additional argument. MFC after: 2 weeks
2005-10-08 21:03:54 +00:00
* running out of vm.boot_pages. Otherwise, we would exhaust the
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
* boot pages. This also prevents us from allocating buckets in
* low memory situations.
*/
if (bucketdisable)
return (NULL);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
/*
* To limit bucket recursion we store the original zone flags
* in a cookie passed via zalloc_arg/zfree_arg. This allows the
* NOVM flag to persist even through deep recursions. We also
* store ZFLAG_BUCKET once we have recursed attempting to allocate
* a bucket for a bucket zone so we do not allow infinite bucket
* recursion. This cookie will even persist to frees of unused
* buckets via the allocation path or bucket allocations in the
* free path.
*/
if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
udata = (void *)(uintptr_t)zone->uz_flags;
Fix bug introduced at r252226, when udata argument passed to bucket_alloc() was used without making sure first that it was really passed for us. On some of my systems this bug made user argument passed by ZFS code to uma_zalloc_arg() unexpectedly block UMA per-CPU caches for those zones.
2013-11-27 19:55:42 +00:00
else {
if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
return (NULL);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
Fix bug introduced at r252226, when udata argument passed to bucket_alloc() was used without making sure first that it was really passed for us. On some of my systems this bug made user argument passed by ZFS code to uma_zalloc_arg() unexpectedly block UMA per-CPU caches for those zones.
2013-11-27 19:55:42 +00:00
}
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
if ((uintptr_t)udata & UMA_ZFLAG_CACHEONLY)
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
flags |= M_NOVM;
ubz = bucket_zone_lookup(zone->uz_count);
Allocating new bucket for bucket zone, never take it from the zone itself, since it will almost certanly fail. Take next bigger zone instead. This situation should not happen with original bucket zones configuration: "32 Bucket" zone uses "64 Bucket" and vice versa. But if "64 Bucket" zone lock is congested, zone may grow its bucket size and start biting itself. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2014-06-12 11:36:22 +00:00
if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
ubz++;
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
if (bucket) {
#ifdef INVARIANTS
bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
#endif
bucket->ub_cnt = 0;
bucket->ub_entries = ubz->ubz_entries;
}
return (bucket);
}
static void
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
{
struct uma_bucket_zone *ubz;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
KASSERT(bucket->ub_cnt == 0,
("bucket_free: Freeing a non free bucket."));
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
udata = (void *)(uintptr_t)zone->uz_flags;
Abstract the logic to look up the uma_bucket_zone given a desired number of entries into bucket_zone_lookup(), which helps make more clear the logic of consumers of bucket zones. Annotate the behavior of bucket_init() with a comment indicating how the various data structures, including the bucket lookup tables, are initialized.
2004-11-06 11:43:30 +00:00
ubz = bucket_zone_lookup(bucket->ub_entries);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
uma_zfree_arg(ubz->ubz_zone, bucket, udata);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
}
static void
bucket_zone_drain(void)
{
struct uma_bucket_zone *ubz;
for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
zone_drain(ubz->ubz_zone);
}
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
static void
zone_log_warning(uma_zone_t zone)
{
static const struct timeval warninterval = { 300, 0 };
if (!zone_warnings || zone->uz_warning == NULL)
return;
if (ratecheck(&zone->uz_ratecheck, &warninterval))
printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
}
Add a safety net to reclaim mbufs when one of the mbuf zones become exhausted. It is possible for a bug in the code (or, theoretically, even unusual network conditions) to exhaust all possible mbufs or mbuf clusters. When this occurs, things can grind to a halt fairly quickly. However, we currently do not call mb_reclaim() unless the entire system is experiencing a low-memory condition. While it is best to try to prevent exhaustion of one of the mbuf zones, it would also be useful to have a mechanism to attempt to recover from these situations by freeing "expendable" mbufs. This patch makes two changes: a) The patch adds a generic API to the UMA zone allocator to set a function that should be called when an allocation fails because the zone limit has been reached. Because of the way this function can be called, it really should do minimal work. b) The patch uses this API to try to free mbufs when an allocation fails from one of the mbuf zones because the zone limit has been reached. The function schedules a callout to run mb_reclaim(). Differential Revision: https://reviews.freebsd.org/D3864 Reviewed by: gnn Comments by: rrs, glebius MFC after: 2 weeks Sponsored by: Juniper Networks
2015-12-20 02:05:33 +00:00
static inline void
zone_maxaction(uma_zone_t zone)
{
Redo r292484. Embed task(9) into zone, so that uz_maxaction is called in a context that can sleep, allowing consumers of the KPI to run their drain routines without any extra measures. Discussed with: jtl
2016-02-03 23:30:17 +00:00
if (zone->uz_maxaction.ta_func != NULL)
taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
Add a safety net to reclaim mbufs when one of the mbuf zones become exhausted. It is possible for a bug in the code (or, theoretically, even unusual network conditions) to exhaust all possible mbufs or mbuf clusters. When this occurs, things can grind to a halt fairly quickly. However, we currently do not call mb_reclaim() unless the entire system is experiencing a low-memory condition. While it is best to try to prevent exhaustion of one of the mbuf zones, it would also be useful to have a mechanism to attempt to recover from these situations by freeing "expendable" mbufs. This patch makes two changes: a) The patch adds a generic API to the UMA zone allocator to set a function that should be called when an allocation fails because the zone limit has been reached. Because of the way this function can be called, it really should do minimal work. b) The patch uses this API to try to free mbufs when an allocation fails from one of the mbuf zones because the zone limit has been reached. The function schedules a callout to run mb_reclaim(). Differential Revision: https://reviews.freebsd.org/D3864 Reviewed by: gnn Comments by: rrs, glebius MFC after: 2 weeks Sponsored by: Juniper Networks
2015-12-20 02:05:33 +00:00
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void
zone_foreach_keg(uma_zone_t zone, void (*kegfn)(uma_keg_t))
{
uma_klink_t klink;
LIST_FOREACH(klink, &zone->uz_kegs, kl_link)
kegfn(klink->kl_keg);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Routine called by timeout which is used to fire off some time interval
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
* based calculations. (stats, hash size, etc.)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Arguments:
* arg Unused
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
*
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* Returns:
* Nothing
*/
static void
uma_timeout(void *unused)
{
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
bucket_enable();
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
zone_foreach(zone_timeout);
/* Reschedule this event */
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
* Routine to perform timeout driven calculations. This expands the
* hashes and does per cpu statistics aggregation.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Returns nothing.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
static void
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_timeout(uma_keg_t keg)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_LOCK(keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Expand the keg hash table.
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
*
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* This is done if the number of slabs is larger than the hash size.
* What I'm trying to do here is completely reduce collisions. This
* may be a little aggressive. Should I allow for two collisions max?
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_flags & UMA_ZONE_HASH &&
keg->uk_pages / keg->uk_ppera >= keg->uk_hash.uh_hashsize) {
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
struct uma_hash newhash;
struct uma_hash oldhash;
int ret;
/*
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* This is so involved because allocating and freeing
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* while the keg lock is held will lead to deadlock.
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
* I have to do everything in stages and check for
* races.
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
newhash = keg->uk_hash;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_UNLOCK(keg);
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
ret = hash_alloc(&newhash);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_LOCK(keg);
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
if (ret) {
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (hash_expand(&keg->uk_hash, &newhash)) {
oldhash = keg->uk_hash;
keg->uk_hash = newhash;
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
} else
oldhash = newhash;
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_UNLOCK(keg);
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
hash_free(&oldhash);
Remove a spurious keg lock acquisition.
2013-06-28 21:13:19 +00:00
return;
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_UNLOCK(keg);
}
static void
zone_timeout(uma_zone_t zone)
{
zone_foreach_keg(zone, &keg_timeout);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
/*
* Allocate and zero fill the next sized hash table from the appropriate
* backing store.
*
* Arguments:
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
* hash A new hash structure with the old hash size in uh_hashsize
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
*
* Returns:
sys/vm: minor spelling fixes in comments. No functional change.
2016-05-02 20:16:29 +00:00
* 1 on success and 0 on failure.
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
*/
Be consistent about "static" functions: if the function is marked static in its prototype, mark it static at the definition too. Inspired by: FlexeLint warning #512
2002-09-28 17:15:38 +00:00
static int
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
hash_alloc(struct uma_hash *hash)
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
{
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
int oldsize;
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
int alloc;
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
oldsize = hash->uh_hashsize;
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
/* We're just going to go to a power of two greater */
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
if (oldsize) {
hash->uh_hashsize = oldsize * 2;
alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
hash->uh_slab_hash = (struct slabhead *)malloc(alloc,
- Don't abuse M_DEVBUF, define a tag for UMA hashes.
2003-09-19 07:23:50 +00:00
M_UMAHASH, M_NOWAIT);
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
} else {
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
Back out M_* changes, per decision of the TRB. Approved by: trb
2003-02-19 05:47:46 +00:00
M_WAITOK);
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
hash->uh_hashsize = UMA_HASH_SIZE_INIT;
}
if (hash->uh_slab_hash) {
bzero(hash->uh_slab_hash, alloc);
hash->uh_hashmask = hash->uh_hashsize - 1;
return (1);
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
}
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
return (0);
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
- There are an endless stream of style(9) errors in this file. Fix a few. Also catch some spelling errors.
2003-09-19 22:31:45 +00:00
* Expands the hash table for HASH zones. This is done from zone_timeout
* to reduce collisions. This must not be done in the regular allocation
* path, otherwise, we can recurse on the vm while allocating pages.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Arguments:
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* oldhash The hash you want to expand
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
* newhash The hash structure for the new table
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Returns:
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* Nothing
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Discussion:
*/
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
static int
hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
uma_slab_t slab;
int hval;
int i;
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
if (!newhash->uh_slab_hash)
return (0);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
if (oldhash->uh_hashsize >= newhash->uh_hashsize)
return (0);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* I need to investigate hash algorithms for resizing without a
* full rehash.
*/
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
for (i = 0; i < oldhash->uh_hashsize; i++)
while (!SLIST_EMPTY(&oldhash->uh_slab_hash[i])) {
slab = SLIST_FIRST(&oldhash->uh_slab_hash[i]);
SLIST_REMOVE_HEAD(&oldhash->uh_slab_hash[i], us_hlink);
hval = UMA_HASH(newhash, slab->us_data);
SLIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
slab, us_hlink);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
return (1);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Fix a witness warning when expanding a hash table. We were allocating the new hash while holding the lock on a zone. Fix this by doing the allocation seperately from the actual hash expansion. The lock is dropped before the allocation and reacquired before the expansion. The expansion code checks to see if we lost the race and frees the new hash if we do. We really never will lose this race because the hash expansion is single threaded via the timeout mechanism.
2002-04-14 13:47:10 +00:00
/*
* Free the hash bucket to the appropriate backing store.
*
* Arguments:
* slab_hash The hash bucket we're freeing
* hashsize The number of entries in that hash bucket
*
* Returns:
* Nothing
*/
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
static void
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
hash_free(struct uma_hash *hash)
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
{
Remove the hash_free() lock order reversal. This could have happened for several reasons before. Fixing it involved restructuring the generic hash code to require calling code to handle locking, unlocking, and freeing hashes on error conditions.
2002-05-13 04:39:28 +00:00
if (hash->uh_slab_hash == NULL)
return;
if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
else
- Don't abuse M_DEVBUF, define a tag for UMA hashes.
2003-09-19 07:23:50 +00:00
free(hash->uh_slab_hash, M_UMAHASH);
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Frees all outstanding items in a bucket
*
* Arguments:
* zone The zone to free to, must be unlocked.
* bucket The free/alloc bucket with items, cpu queue must be locked.
*
* Returns:
* Nothing
*/
static void
bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
{
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
int i;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
if (bucket == NULL)
return;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (zone->uz_fini)
for (i = 0; i < bucket->ub_cnt; i++)
zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
bucket->ub_cnt = 0;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
* Drains the per cpu caches for a zone.
*
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
* NOTE: This may only be called while the zone is being turn down, and not
* during normal operation. This is necessary in order that we do not have
* to migrate CPUs to drain the per-CPU caches.
*
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* Arguments:
Plug a race and a leak in UMA. 1) The race has to do with zone destruction. From the zone destructor we would lock the zone, set the working set size to 0, then unlock the zone, drain it, and then free the structure. Within the window following the working-set-size set to 0 and unlocking of the zone and the point where in zone_drain we re-acquire the zone lock, the uma timer routine could have fired off and changed the working set size to something non-zero, thereby potentially preventing us from completely freeing slabs before destroying the zone (and thus leaking them). 2) The leak has to do with zone destruction as well. When destroying a zone we would take care to free all the buckets cached in the zone, but although we would drain the pcpu cache buckets, we would not free them. This resulted in leaking a couple of bucket structures (512 bytes each) per cpu on SMP during zone destruction. While I'm here, also silence GCC warnings by turning uma_slab_alloc() from inline to real function. It's too big to be an inline. Reviewed by: JeffR
2003-07-30 18:55:15 +00:00
* zone The zone to drain, must be unlocked.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Returns:
* Nothing
*/
static void
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
cache_drain(uma_zone_t zone)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
uma_cache_t cache;
int cpu;
/*
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
* XXX: It is safe to not lock the per-CPU caches, because we're
* tearing down the zone anyway. I.e., there will be no further use
* of the caches at this point.
*
* XXX: It would good to be able to assert that the zone is being
* torn down to prevent improper use of cache_drain().
*
* XXX: We lock the zone before passing into bucket_cache_drain() as
* it is used elsewhere. Should the tear-down path be made special
* there in some form?
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
Update several places that iterate over CPUs to use CPU_FOREACH().
2010-06-11 18:46:34 +00:00
CPU_FOREACH(cpu) {
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
cache = &zone->uz_cpu[cpu];
bucket_drain(zone, cache->uc_allocbucket);
bucket_drain(zone, cache->uc_freebucket);
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
if (cache->uc_allocbucket != NULL)
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_free(zone, cache->uc_allocbucket, NULL);
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
if (cache->uc_freebucket != NULL)
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_free(zone, cache->uc_freebucket, NULL);
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
cache->uc_allocbucket = cache->uc_freebucket = NULL;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Fix a problem where we did not drain the cache of buckets in the zone when uma_reclaim() was called. This was introduced when the zone working-set algorithm was removed in favor of using the per cpu caches as the working set.
2004-02-01 06:15:17 +00:00
ZONE_LOCK(zone);
bucket_cache_drain(zone);
ZONE_UNLOCK(zone);
}
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
static void
cache_shrink(uma_zone_t zone)
{
if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
return;
ZONE_LOCK(zone);
zone->uz_count = (zone->uz_count_min + zone->uz_count) / 2;
ZONE_UNLOCK(zone);
}
static void
cache_drain_safe_cpu(uma_zone_t zone)
{
uma_cache_t cache;
When purging per-CPU UMA caches do not return empty buckets into the global full bucket cache to not trigger assertion if allocation happen before that global cache get purged.
2013-11-23 13:42:56 +00:00
uma_bucket_t b1, b2;
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
return;
When purging per-CPU UMA caches do not return empty buckets into the global full bucket cache to not trigger assertion if allocation happen before that global cache get purged.
2013-11-23 13:42:56 +00:00
b1 = b2 = NULL;
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
ZONE_LOCK(zone);
critical_enter();
cache = &zone->uz_cpu[curcpu];
if (cache->uc_allocbucket) {
When purging per-CPU UMA caches do not return empty buckets into the global full bucket cache to not trigger assertion if allocation happen before that global cache get purged.
2013-11-23 13:42:56 +00:00
if (cache->uc_allocbucket->ub_cnt != 0)
LIST_INSERT_HEAD(&zone->uz_buckets,
cache->uc_allocbucket, ub_link);
else
b1 = cache->uc_allocbucket;
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
cache->uc_allocbucket = NULL;
}
if (cache->uc_freebucket) {
When purging per-CPU UMA caches do not return empty buckets into the global full bucket cache to not trigger assertion if allocation happen before that global cache get purged.
2013-11-23 13:42:56 +00:00
if (cache->uc_freebucket->ub_cnt != 0)
LIST_INSERT_HEAD(&zone->uz_buckets,
cache->uc_freebucket, ub_link);
else
b2 = cache->uc_freebucket;
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
cache->uc_freebucket = NULL;
}
critical_exit();
ZONE_UNLOCK(zone);
When purging per-CPU UMA caches do not return empty buckets into the global full bucket cache to not trigger assertion if allocation happen before that global cache get purged.
2013-11-23 13:42:56 +00:00
if (b1)
bucket_free(zone, b1, NULL);
if (b2)
bucket_free(zone, b2, NULL);
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
}
/*
* Safely drain per-CPU caches of a zone(s) to alloc bucket.
* This is an expensive call because it needs to bind to all CPUs
* one by one and enter a critical section on each of them in order
* to safely access their cache buckets.
* Zone lock must not be held on call this function.
*/
static void
cache_drain_safe(uma_zone_t zone)
{
int cpu;
/*
* Polite bucket sizes shrinking was not enouth, shrink aggressively.
*/
if (zone)
cache_shrink(zone);
else
zone_foreach(cache_shrink);
CPU_FOREACH(cpu) {
thread_lock(curthread);
sched_bind(curthread, cpu);
thread_unlock(curthread);
if (zone)
cache_drain_safe_cpu(zone);
else
zone_foreach(cache_drain_safe_cpu);
}
thread_lock(curthread);
sched_unbind(curthread);
thread_unlock(curthread);
}
- Fix a problem where we did not drain the cache of buckets in the zone when uma_reclaim() was called. This was introduced when the zone working-set algorithm was removed in favor of using the per cpu caches as the working set.
2004-02-01 06:15:17 +00:00
/*
* Drain the cached buckets from a zone. Expects a locked zone on entry.
*/
static void
bucket_cache_drain(uma_zone_t zone)
{
uma_bucket_t bucket;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Drain the bucket queues and free the buckets, we just keep two per
* cpu (alloc/free).
*/
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
while ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
LIST_REMOVE(bucket, ub_link);
ZONE_UNLOCK(zone);
bucket_drain(zone, bucket);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_free(zone, bucket, NULL);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
ZONE_LOCK(zone);
}
Implement soft pressure on UMA cache bucket sizes. Every time system detects low memory condition decrease bucket sizes for each zone by one item. As result, higher memory pressure will push to smaller bucket sizes and so smaller per-CPU caches and so more efficient memory use. Before this change there was no force to oppose buckets growth as result of practically inevitable zone lock conflicts, and after some run time per-CPU caches could consume enough RAM to kill the system.
2013-11-19 10:05:53 +00:00
/*
* Shrink further bucket sizes. Price of single zone lock collision
* is probably lower then price of global cache drain.
*/
if (zone->uz_count > zone->uz_count_min)
zone->uz_count--;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
static void
keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
{
uint8_t *mem;
int i;
uint8_t flags;
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
mem = slab->us_data;
flags = slab->us_flags;
i = start;
if (keg->uk_fini != NULL) {
for (i--; i > -1; i--)
keg->uk_fini(slab->us_data + (keg->uk_rsize * i),
keg->uk_size);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (keg->uk_flags & UMA_ZONE_OFFPAGE)
zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
keg->uk_freef(mem, PAGE_SIZE * keg->uk_ppera, flags);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Frees pages from a keg back to the system. This is done on demand from
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* the pageout daemon.
*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Returns nothing.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void
keg_drain(uma_keg_t keg)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
ISO C requires at least one element in an initialiser list.
2005-01-10 20:30:04 +00:00
struct slabhead freeslabs = { 0 };
Simplify keg_drain() a bit by using LIST_FOREACH_SAFE. MFC after: 1 week
2016-10-20 23:10:27 +00:00
uma_slab_t slab, tmp;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* We don't want to take pages from statically allocated kegs at this
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* time
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_flags & UMA_ZONE_NOFREE || keg->uk_freef == NULL)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
return;
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR3(KTR_UMA, "keg_drain %s(%p) free items: %u",
keg->uk_name, keg, keg->uk_free);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_LOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_free == 0)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
goto finished;
Simplify keg_drain() a bit by using LIST_FOREACH_SAFE. MFC after: 1 week
2016-10-20 23:10:27 +00:00
LIST_FOREACH_SAFE(slab, &keg->uk_free_slab, us_link, tmp) {
/* We have nowhere to free these to. */
if (slab->us_flags & UMA_SLAB_BOOT)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
continue;
LIST_REMOVE(slab, us_link);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_pages -= keg->uk_ppera;
keg->uk_free -= keg->uk_ipers;
Don't call the uz free function while the zone lock is held. This can lead to lock order reversals. uma_reclaim now builds a list of freeable slabs and then unlocks the zones to do all of the frees.
2002-05-13 05:08:18 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_flags & UMA_ZONE_HASH)
UMA_HASH_REMOVE(&keg->uk_hash, slab, slab->us_data);
Don't call the uz free function while the zone lock is held. This can lead to lock order reversals. uma_reclaim now builds a list of freeable slabs and then unlocks the zones to do all of the frees.
2002-05-13 05:08:18 +00:00
SLIST_INSERT_HEAD(&freeslabs, slab, us_hlink);
}
finished:
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_UNLOCK(keg);
Don't call the uz free function while the zone lock is held. This can lead to lock order reversals. uma_reclaim now builds a list of freeable slabs and then unlocks the zones to do all of the frees.
2002-05-13 05:08:18 +00:00
while ((slab = SLIST_FIRST(&freeslabs)) != NULL) {
SLIST_REMOVE(&freeslabs, slab, uma_slab, us_hlink);
Fix bug introduced in rewrite of keg_free_slab in -r251894. The consequence of the bug is that fini calls are not done when a slab is freed by a call-back from the page daemon. It went unnoticed for two months because fini is little used. I spotted the bug while reading the code to learn how it works so I could write it up for the next edition of the Design and Implementation of FreeBSD book. No MFC needed as this code exists only in HEAD. Reviewed by: kib, jeff Tested by: pho
2013-08-31 15:40:15 +00:00
keg_free_slab(keg, slab, keg->uk_ipers);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void
zone_drain_wait(uma_zone_t zone, int waitok)
{
/*
* Set draining to interlock with zone_dtor() so we can release our
* locks as we go. Only dtor() should do a WAITOK call since it
* is the only call that knows the structure will still be available
* when it wakes up.
*/
ZONE_LOCK(zone);
while (zone->uz_flags & UMA_ZFLAG_DRAINING) {
if (waitok == M_NOWAIT)
goto out;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
msleep(zone, zone->uz_lockptr, PVM, "zonedrain", 1);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
zone->uz_flags |= UMA_ZFLAG_DRAINING;
bucket_cache_drain(zone);
ZONE_UNLOCK(zone);
/*
* The DRAINING flag protects us from being freed while
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
* we're running. Normally the uma_rwlock would protect us but we
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* must be able to release and acquire the right lock for each keg.
*/
zone_foreach_keg(zone, &keg_drain);
ZONE_LOCK(zone);
zone->uz_flags &= ~UMA_ZFLAG_DRAINING;
wakeup(zone);
out:
ZONE_UNLOCK(zone);
}
void
zone_drain(uma_zone_t zone)
{
zone_drain_wait(zone, M_NOWAIT);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Allocate a new slab for a keg. This does not insert the slab onto a list.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Arguments:
* wait Shall we wait?
*
* Returns:
* The slab that was allocated or NULL if there is no memory and the
* caller specified M_NOWAIT.
*/
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
static uma_slab_t
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int wait)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_alloc allocf;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_slab_t slab;
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint8_t *mem;
uint8_t flags;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
int i;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
mtx_assert(&keg->uk_lock, MA_OWNED);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
slab = NULL;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
mem = NULL;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
allocf = keg->uk_allocf;
KEG_UNLOCK(keg);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_flags & UMA_ZONE_OFFPAGE) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
slab = zone_alloc_item(keg->uk_slabzone, NULL, wait);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (slab == NULL)
goto out;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
}
- Remove bogus use of kmem_alloc that was inherited from the old zone allocator. - Properly set M_ZERO when talking to the back end page allocators for non malloc zones. This forces us to zero fill pages when they are first brought into a cache. - Properly handle M_ZERO in uma_zalloc_internal. This fixes a problem where per cpu buckets weren't always getting zeroed.
2002-06-19 20:49:44 +00:00
/*
* This reproduces the old vm_zone behavior of zero filling pages the
* first time they are added to a zone.
*
* Malloced items are zeroed in uma_zalloc.
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
- Remove bogus use of kmem_alloc that was inherited from the old zone allocator. - Properly set M_ZERO when talking to the back end page allocators for non malloc zones. This forces us to zero fill pages when they are first brought into a cache. - Properly handle M_ZERO in uma_zalloc_internal. This fixes a problem where per cpu buckets weren't always getting zeroed.
2002-06-19 20:49:44 +00:00
wait |= M_ZERO;
else
wait &= ~M_ZERO;
exclude kmem_alloc'ed ARC data buffers from kernel minidumps on amd64 excluding other allocations including UMA now entails the addition of a single flag to kmem_alloc or uma zone create Reviewed by: alc, avg MFC after: 2 weeks
2012-01-27 20:18:31 +00:00
if (keg->uk_flags & UMA_ZONE_NODUMP)
wait |= M_NODUMP;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
/* zone is passed for legacy reasons. */
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
mem = allocf(zone, keg->uk_ppera * PAGE_SIZE, &flags, wait);
- Move the logic for dealing with the uma_boot_pages cache into the page_alloc() function from the slab_zalloc() function. This allows us to unconditionally call uz_allocf(). - In page_alloc() cleanup the boot_pages logic some. Previously memory from this cache that was not used by the time the system started was left in the cache and never used. Typically this wasn't more than a few pages, but now we will use this cache so long as memory is available.
2003-09-19 08:53:33 +00:00
if (mem == NULL) {
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
if (keg->uk_flags & UMA_ZONE_OFFPAGE)
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(keg->uk_slabzone, slab, NULL, SKIP_NONE);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
slab = NULL;
goto out;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Reduce the amount of code that runs with the zone lock held in slab_zalloc(). This allows us to run the zone initialization functions without any locks held.
2002-06-25 21:04:50 +00:00
/* Point the slab into the allocated memory */
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (!(keg->uk_flags & UMA_ZONE_OFFPAGE))
slab = (uma_slab_t )(mem + keg->uk_pgoff);
Reduce the amount of code that runs with the zone lock held in slab_zalloc(). This allows us to run the zone initialization functions without any locks held.
2002-06-25 21:04:50 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (keg->uk_flags & UMA_ZONE_VTOSLAB)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
for (i = 0; i < keg->uk_ppera; i++)
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
vsetslab((vm_offset_t)mem + (i * PAGE_SIZE), slab);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
slab->us_keg = keg;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
slab->us_data = mem;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
slab->us_freecount = keg->uk_ipers;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
slab->us_flags = flags;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
BIT_FILL(SLAB_SETSIZE, &slab->us_free);
#ifdef INVARIANTS
BIT_ZERO(SLAB_SETSIZE, &slab->us_debugfree);
#endif
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
if (keg->uk_init != NULL) {
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
for (i = 0; i < keg->uk_ipers; i++)
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
if (keg->uk_init(slab->us_data + (keg->uk_rsize * i),
keg->uk_size, wait) != 0)
break;
if (i != keg->uk_ipers) {
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
keg_free_slab(keg, slab, i);
slab = NULL;
goto out;
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
}
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
out:
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_LOCK(keg);
Reduce the amount of code that runs with the zone lock held in slab_zalloc(). This allows us to run the zone initialization functions without any locks held.
2002-06-25 21:04:50 +00:00
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
slab, keg->uk_name, keg);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (slab != NULL) {
if (keg->uk_flags & UMA_ZONE_HASH)
UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
keg->uk_pages += keg->uk_ppera;
keg->uk_free += keg->uk_ipers;
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
return (slab);
}
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
/*
* This function is intended to be used early on in place of page_alloc() so
* that we may use the boot time page cache to satisfy allocations before
* the VM is ready.
*/
static void *
Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM. Note to self: When this is MFCed, sparc64 needs the same fix. Differential revision: https://reviews.freebsd.org/D2106 Reviewed by: kib Reported by: Michael Fuckner <michael@fuckner.net> Tested by: Michael Fuckner <michael@fuckner.net> MFC after: 2 weeks
2015-04-01 12:42:26 +00:00
startup_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
{
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
Simplify boot pages management in UMA. It is simply a contigous virtual memory pointer and number of pages. There is no need to build a linked list here. Just increment pointer and decrement counter. The only functional difference to old allocator is that before we gave pages from topmost and down to lowest, and now we give them in normal ascending order. While here remove padalign from a mutex that is unused at runtime. Reviewed by: alc
2017-06-01 18:26:57 +00:00
void *mem;
int pages;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
Update startup_alloc() to support multi-page allocations and allow internal zones whose objects are larger than a page to use startup_alloc(). This allows allocation of zone objects during early boot on machines with a large number of CPUs since the resulting zone objects are larger than a page. Submitted by: trema Reviewed by: attilio MFC after: 1 week
2010-11-04 15:33:50 +00:00
pages = howmany(bytes, PAGE_SIZE);
KASSERT(pages > 0, ("startup_alloc can't reserve 0 pages\n"));
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
/*
* Check our small startup cache to see if it has pages remaining.
*/
Introduce a new lock for the purpose of synchronizing access to the UMA boot pages. Disable recursion on the general UMA lock now that startup_alloc() no longer uses it. Eliminate the variable uma_boot_free. It serves no purpose. Note: This change eliminates a lock-order reversal between a system map mutex and the UMA lock. See http://sources.zabbadoz.net/freebsd/lor.html#109 for details. MFC after: 3 days
2005-09-09 06:03:08 +00:00
mtx_lock(&uma_boot_pages_mtx);
Simplify boot pages management in UMA. It is simply a contigous virtual memory pointer and number of pages. There is no need to build a linked list here. Just increment pointer and decrement counter. The only functional difference to old allocator is that before we gave pages from topmost and down to lowest, and now we give them in normal ascending order. While here remove padalign from a mutex that is unused at runtime. Reviewed by: alc
2017-06-01 18:26:57 +00:00
if (pages <= boot_pages) {
mem = bootmem;
boot_pages -= pages;
bootmem += pages * PAGE_SIZE;
Introduce a new lock for the purpose of synchronizing access to the UMA boot pages. Disable recursion on the general UMA lock now that startup_alloc() no longer uses it. Eliminate the variable uma_boot_free. It serves no purpose. Note: This change eliminates a lock-order reversal between a system map mutex and the UMA lock. See http://sources.zabbadoz.net/freebsd/lor.html#109 for details. MFC after: 3 days
2005-09-09 06:03:08 +00:00
mtx_unlock(&uma_boot_pages_mtx);
Simplify boot pages management in UMA. It is simply a contigous virtual memory pointer and number of pages. There is no need to build a linked list here. Just increment pointer and decrement counter. The only functional difference to old allocator is that before we gave pages from topmost and down to lowest, and now we give them in normal ascending order. While here remove padalign from a mutex that is unused at runtime. Reviewed by: alc
2017-06-01 18:26:57 +00:00
*pflag = UMA_SLAB_BOOT;
return (mem);
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
}
Introduce a new lock for the purpose of synchronizing access to the UMA boot pages. Disable recursion on the general UMA lock now that startup_alloc() no longer uses it. Eliminate the variable uma_boot_free. It serves no purpose. Note: This change eliminates a lock-order reversal between a system map mutex and the UMA lock. See http://sources.zabbadoz.net/freebsd/lor.html#109 for details. MFC after: 3 days
2005-09-09 06:03:08 +00:00
mtx_unlock(&uma_boot_pages_mtx);
1. Prior to r214782, UMA did not support multipage allocations before uma_startup2() was called. Thus, setting the variable "booted" to true in uma_startup() was ok on machines with UMA_MD_SMALL_ALLOC defined, because any allocations made after uma_startup() but before uma_startup2() could be satisfied by uma_small_alloc(). Now, however, some multipage allocations are necessary before uma_startup2() just to allocate zone structures on machines with a large number of processors. Thus, a Boolean can no longer effectively describe the state of the UMA allocator. Instead, make "booted" have three values to describe how far initialization has progressed. This allows multipage allocations to continue using startup_alloc() until uma_startup2(), but single-page allocations may begin using uma_small_alloc() after uma_startup(). 2. With the aforementioned change, only a modest increase in boot pages is necessary to boot UMA on a large number of processors. 3. Retire UMA_MD_SMALL_ALLOC_NEEDS_VM. It has only been used between r182028 and r204128. Reviewed by: attilio [1], nwhitehorn [3] Tested by: sbruno
2011-05-21 17:43:43 +00:00
if (booted < UMA_STARTUP2)
As alc pointed out to me, vm_page.c 1.305 was incomplete: uma_startup() still uses the constant UMA_BOOT_PAGES. Change it to accept boot_pages as an additional argument. MFC after: 2 weeks
2005-10-08 21:03:54 +00:00
panic("UMA: Increase vm.boot_pages");
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
/*
* Now that we've booted reset these users to their real allocator.
*/
#ifdef UMA_MD_SMALL_ALLOC
Update startup_alloc() to support multi-page allocations and allow internal zones whose objects are larger than a page to use startup_alloc(). This allows allocation of zone objects during early boot on machines with a large number of CPUs since the resulting zone objects are larger than a page. Submitted by: trema Reviewed by: attilio MFC after: 1 week
2010-11-04 15:33:50 +00:00
keg->uk_allocf = (keg->uk_ppera > 1) ? page_alloc : uma_small_alloc;
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
#else
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_allocf = page_alloc;
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
#endif
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
return keg->uk_allocf(zone, bytes, pflag, wait);
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Allocates a number of pages from the system
*
* Arguments:
* bytes The number of bytes requested
* wait Shall we wait?
*
* Returns:
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* A pointer to the alloced memory or possibly
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* NULL if M_NOWAIT is set.
*/
static void *
Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM. Note to self: When this is MFCed, sparc64 needs the same fix. Differential revision: https://reviews.freebsd.org/D2106 Reviewed by: kib Reported by: Michael Fuckner <michael@fuckner.net> Tested by: Michael Fuckner <michael@fuckner.net> MFC after: 2 weeks
2015-04-01 12:42:26 +00:00
page_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
void *p; /* Returned page */
- Remove bogus use of kmem_alloc that was inherited from the old zone allocator. - Properly set M_ZERO when talking to the back end page allocators for non malloc zones. This forces us to zero fill pages when they are first brought into a cache. - Properly handle M_ZERO in uma_zalloc_internal. This fixes a problem where per cpu buckets weren't always getting zeroed.
2002-06-19 20:49:44 +00:00
*pflag = UMA_SLAB_KMEM;
Replace kernel virtual address space allocation with vmem. This provides transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
2013-08-07 06:21:20 +00:00
p = (void *) kmem_malloc(kmem_arena, bytes, wait);
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
return (p);
}
/*
* Allocates a number of pages from within an object
*
* Arguments:
* bytes The number of bytes requested
* wait Shall we wait?
*
* Returns:
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* A pointer to the alloced memory or possibly
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* NULL if M_NOWAIT is set.
*/
static void *
Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM. Note to self: When this is MFCed, sparc64 needs the same fix. Differential revision: https://reviews.freebsd.org/D2106 Reviewed by: kib Reported by: Michael Fuckner <michael@fuckner.net> Tested by: Michael Fuckner <michael@fuckner.net> MFC after: 2 weeks
2015-04-01 12:42:26 +00:00
noobj_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *flags, int wait)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
MFC
2013-02-26 23:52:23 +00:00
TAILQ_HEAD(, vm_page) alloctail;
u_long npages;
Revise obj_alloc(). Most notably, use the object's lock to prevent two concurrent invocations from acquiring the same address(es). Also, in case of an incomplete allocation, free any allocated pages. In collaboration with: tegge
2003-08-03 06:08:48 +00:00
vm_offset_t retkva, zkva;
MFC
2013-02-26 23:52:23 +00:00
vm_page_t p, p_next;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t keg;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
MFC
2013-02-26 23:52:23 +00:00
TAILQ_INIT(&alloctail);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
MFC
2013-02-26 23:52:23 +00:00
npages = howmany(bytes, PAGE_SIZE);
while (npages > 0) {
p = vm_page_alloc(NULL, 0, VM_ALLOC_INTERRUPT |
Replace manyinstances of VM_WAIT with blocking page allocation flags similar to the kernel memory allocator. This simplifies NUMA allocation because the domain will be known at wait time and races between failure and sleeping are eliminated. This also reduces boilerplate code and simplifies callers. A wait primitive is supplied for uma zones for similar reasons. This eliminates some non-specific VM_WAIT calls in favor of more explicit sleeps that may be satisfied without new pages. Reviewed by: alc, kib, markj Tested by: pho Sponsored by: Netflix, Dell/EMC Isilon
2017-11-08 02:39:37 +00:00
VM_ALLOC_WIRED | VM_ALLOC_NOOBJ |
Fix operator priority. Sponsored by: The FreeBSD Foundation
2017-11-08 23:25:05 +00:00
((wait & M_WAITOK) != 0 ? VM_ALLOC_WAITOK :
VM_ALLOC_NOWAIT));
MFC
2013-02-26 23:52:23 +00:00
if (p != NULL) {
/*
* Since the page does not belong to an object, its
* listq is unused.
*/
TAILQ_INSERT_TAIL(&alloctail, p, listq);
npages--;
continue;
}
/*
* Page allocation failed, free intermediate pages and
* exit.
*/
TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
Exploit r288122 to address a cosmetic issue. Since the pages allocated by noobj_alloc() don't belong to a vm object, they can't be paged out. Since they can't be paged out, they are never enqueued in a paging queue. Nonetheless, passing PQ_INACTIVE to vm_page_unwire() creates the appearance that these pages are being enqueued in the inactive queue. As of r288122, we can avoid giving this false impression by passing PQ_NONE. Submitted by: kmacy Differential Revision: https://reviews.freebsd.org/D1674
2015-09-26 17:45:10 +00:00
vm_page_unwire(p, PQ_NONE);
MFC
2013-02-26 23:52:23 +00:00
vm_page_free(p);
}
return (NULL);
}
*flags = UMA_SLAB_PRIV;
zkva = keg->uk_kva +
atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
retkva = zkva;
TAILQ_FOREACH(p, &alloctail, listq) {
Revise obj_alloc(). Most notably, use the object's lock to prevent two concurrent invocations from acquiring the same address(es). Also, in case of an incomplete allocation, free any allocated pages. In collaboration with: tegge
2003-08-03 06:08:48 +00:00
pmap_qenter(zkva, &p, 1);
zkva += PAGE_SIZE;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
return ((void *)retkva);
}
/*
* Frees a number of pages to the system
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
*
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* Arguments:
* mem A pointer to the memory to be freed
* size The size of the memory being freed
* flags The original p->us_flags field
*
* Returns:
* Nothing
*/
static void
Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM. Note to self: When this is MFCed, sparc64 needs the same fix. Differential revision: https://reviews.freebsd.org/D2106 Reviewed by: kib Reported by: Michael Fuckner <michael@fuckner.net> Tested by: Michael Fuckner <michael@fuckner.net> MFC after: 2 weeks
2015-04-01 12:42:26 +00:00
page_free(void *mem, vm_size_t size, uint8_t flags)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
Replace kernel virtual address space allocation with vmem. This provides transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
2013-08-07 06:21:20 +00:00
struct vmem *vmem;
- Remove bogus use of kmem_alloc that was inherited from the old zone allocator. - Properly set M_ZERO when talking to the back end page allocators for non malloc zones. This forces us to zero fill pages when they are first brought into a cache. - Properly handle M_ZERO in uma_zalloc_internal. This fixes a problem where per cpu buckets weren't always getting zeroed.
2002-06-19 20:49:44 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
if (flags & UMA_SLAB_KMEM)
Replace kernel virtual address space allocation with vmem. This provides transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
2013-08-07 06:21:20 +00:00
vmem = kmem_arena;
Add support for UMA_SLAB_KERNEL to page_free(). (While I'm here remove an unnecessary newline character from the end of two panic messages.)
2009-06-18 07:27:11 +00:00
else if (flags & UMA_SLAB_KERNEL)
Replace kernel virtual address space allocation with vmem. This provides transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
2013-08-07 06:21:20 +00:00
vmem = kernel_arena;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
else
Print flags in hex instead of decimal. Hex is easier to grok for flags, and consistent with other prints.
2017-01-02 16:50:52 +00:00
panic("UMA: page_free used with invalid flags %x", flags);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Replace kernel virtual address space allocation with vmem. This provides transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
2013-08-07 06:21:20 +00:00
kmem_free(vmem, (vm_offset_t)mem, size);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
* Zero fill initializer
*
* Arguments/Returns follow uma_init specifications
*/
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
static int
zero_init(void *mem, int size, int flags)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
bzero(mem, size);
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
return (0);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Finish creating a small uma keg. This calculates ipers, and the keg size.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Arguments
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* keg The zone we should initialize
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Returns
* Nothing
*/
static void
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_small_init(uma_keg_t keg)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
u_int rsize;
u_int memused;
u_int wastedspace;
u_int shsize;
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
u_int slabsize;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
if (keg->uk_flags & UMA_ZONE_PCPU) {
Replace a number of conflations of mp_ncpus and mp_maxid with either mp_maxid or CPU_FOREACH() as appropriate. This fixes a number of places in the kernel that assumed CPU IDs are dense in [0, mp_ncpus) and would try, for example, to run tasks on CPUs that did not exist or to allocate too few buffers on systems with sparse CPU IDs in which there are holes in the range and mp_maxid > mp_ncpus. Such circumstances generally occur on systems with SMT, but on which SMT is disabled. This patch restores system operation at least on POWER8 systems configured in this way. There are a number of other places in the kernel with potential problems in these situations, but where sparse CPU IDs are not currently known to occur, mostly in the ARM machine-dependent code. These will be fixed in a follow-up commit after the stable/11 branch. PR: kern/210106 Reviewed by: jhb Approved by: re (glebius)
2016-07-06 14:09:49 +00:00
u_int ncpus = (mp_maxid + 1) ? (mp_maxid + 1) : MAXCPU;
Revert r249590 and in case if mp_ncpus isn't initialized use MAXCPU. This allows us to init counter zone at early stage of boot. Reviewed by: kib Tested by: Lytochkin Boris <lytboris gmail.com>
2013-07-23 11:16:40 +00:00
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
slabsize = sizeof(struct pcpu);
Revert r249590 and in case if mp_ncpus isn't initialized use MAXCPU. This allows us to init counter zone at early stage of boot. Reviewed by: kib Tested by: Lytochkin Boris <lytboris gmail.com>
2013-07-23 11:16:40 +00:00
keg->uk_ppera = howmany(ncpus * sizeof(struct pcpu),
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
PAGE_SIZE);
} else {
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
slabsize = UMA_SLAB_SIZE;
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
keg->uk_ppera = 1;
}
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
/*
* Calculate the size of each allocation (rsize) according to
* alignment. If the requested size is smaller than we have
* allocation bits for we round it up.
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
rsize = keg->uk_size;
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
if (rsize < slabsize / SLAB_SETSIZE)
rsize = slabsize / SLAB_SETSIZE;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (rsize & keg->uk_align)
rsize = (rsize & ~keg->uk_align) + (keg->uk_align + 1);
keg->uk_rsize = rsize;
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
keg->uk_rsize < sizeof(struct pcpu),
("%s: size %u too large", __func__, keg->uk_rsize));
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
if (keg->uk_flags & UMA_ZONE_OFFPAGE)
If caller specifies UMA_ZONE_OFFPAGE explicitly, then do not waste memory in an allocation for a slab. Reviewed by: jeff
2012-09-18 20:28:55 +00:00
shsize = 0;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
else
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
shsize = sizeof(struct uma_slab);
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
keg->uk_ipers = (slabsize - shsize) / rsize;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
memused = keg->uk_ipers * rsize + shsize;
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
wastedspace = slabsize - memused;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
/*
* We can't do OFFPAGE if we're internal or if we've been
* asked to not go to the VM for buckets. If we do this we
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
* may end up going to the VM for slabs which we do not
* want to do if we're UMA_ZFLAG_CACHEONLY as a result
* of UMA_ZONE_VM, which clearly forbids it.
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
*/
if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) ||
(keg->uk_flags & UMA_ZFLAG_CACHEONLY))
return;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
/*
* See if using an OFFPAGE slab will limit our waste. Only do
* this if it permits more items per-slab.
*
* XXX We could try growing slabsize to limit max waste as well.
* Historically this was not done because the VM could not
* efficiently handle contiguous allocations.
*/
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
if ((wastedspace >= slabsize / UMA_MAX_WASTE) &&
(keg->uk_ipers < (slabsize / keg->uk_rsize))) {
keg->uk_ipers = slabsize / keg->uk_rsize;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_SETSIZE,
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
("%s: keg->uk_ipers %u", __func__, keg->uk_ipers));
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR6(KTR_UMA, "UMA decided we need offpage slab headers for "
"keg: %s(%p), calculated wastedspace = %d, "
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
"maximum wasted space allowed = %d, "
"calculated ipers = %d, "
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
"new wasted space = %d\n", keg->uk_name, keg, wastedspace,
uma: eliminate uk_slabsize field The field was not used beyond the initial keg setup stage anyway. MFC after: 1 month (if ever)
2017-03-11 16:35:36 +00:00
slabsize / UMA_MAX_WASTE, keg->uk_ipers,
slabsize - keg->uk_ipers * keg->uk_rsize);
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
keg->uk_flags |= UMA_ZONE_OFFPAGE;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
(keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
keg->uk_flags |= UMA_ZONE_HASH;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* Finish creating a large (> UMA_SLAB_SIZE) uma kegs. Just give in and do
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* OFFPAGE for now. When I can allow for more dynamic slab sizes this will be
* more complicated.
*
* Arguments
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
* keg The keg we should initialize
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Returns
* Nothing
*/
static void
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_large_init(uma_keg_t keg)
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
{
Make UMA to not blindly force offpage slab header allocation for large (> PAGE_SIZE) zones. If zone is not multiple to PAGE_SIZE, there may be enough space for the header at the last page, so we may avoid extra header memory allocation and hash table update/lookup. ZFS creates bunch of odd-sized UMA zones (5120, 6144, 7168, 10240, 14336). This change gives good use to at least some of otherwise lost memory there. Reviewed by: avg
2013-11-27 20:56:10 +00:00
u_int shsize;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KASSERT(keg != NULL, ("Keg is null in keg_large_init"));
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
KASSERT((keg->uk_flags & UMA_ZFLAG_CACHEONLY) == 0,
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
("keg_large_init: Cannot large-init a UMA_ZFLAG_CACHEONLY keg"));
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
("%s: Cannot large-init a UMA_ZONE_PCPU keg", __func__));
- When deciding whether to init the zone with small_init or large_init, compare the zone element size (+1 for the byte of linkage) against UMA_SLAB_SIZE - sizeof(struct uma_slab), and not just UMA_SLAB_SIZE. Add a KASSERT in zone_small_init to make sure that the computed ipers (items per slab) for the zone is not zero, despite the addition of the check, just to be sure (this part submitted by: silby) - UMA_ZONE_VM used to imply BUCKETCACHE. Now it implies CACHEONLY instead. CACHEONLY is like BUCKETCACHE in the case of bucket allocations, but in addition to that also ensures that we don't setup the zone with OFFPAGE slab headers allocated from the slabzone. This means that we're not allowed to have a UMA_ZONE_VM zone initialized for large items (zone_large_init) because it would require the slab headers to be allocated from slabzone, and hence kmem_map. Some of the zones init'd with UMA_ZONE_VM are so init'd before kmem_map is suballoc'd from kernel_map, which is why this change is necessary.
2003-08-11 19:39:45 +00:00
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
keg->uk_ppera = howmany(keg->uk_size, PAGE_SIZE);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_ipers = 1;
Update startup_alloc() to support multi-page allocations and allow internal zones whose objects are larger than a page to use startup_alloc(). This allows allocation of zone objects during early boot on machines with a large number of CPUs since the resulting zone objects are larger than a page. Submitted by: trema Reviewed by: attilio MFC after: 1 week
2010-11-04 15:33:50 +00:00
keg->uk_rsize = keg->uk_size;
Make UMA to not blindly force offpage slab header allocation for large (> PAGE_SIZE) zones. If zone is not multiple to PAGE_SIZE, there may be enough space for the header at the last page, so we may avoid extra header memory allocation and hash table update/lookup. ZFS creates bunch of odd-sized UMA zones (5120, 6144, 7168, 10240, 14336). This change gives good use to at least some of otherwise lost memory there. Reviewed by: avg
2013-11-27 20:56:10 +00:00
/* Check whether we have enough space to not do OFFPAGE. */
if ((keg->uk_flags & UMA_ZONE_OFFPAGE) == 0) {
shsize = sizeof(struct uma_slab);
if (shsize & UMA_ALIGN_PTR)
shsize = (shsize & ~UMA_ALIGN_PTR) +
(UMA_ALIGN_PTR + 1);
Fix a logic error in the item size calculation for internal UMA zones. Kegs for internal zones always keep the slab header in the slab itself. Therefore, when determining the allocation size, we need to take the slab header size into account. Reported and tested by: ae, rakuco Reviewed by: avg MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D12342
2017-09-13 15:44:54 +00:00
if (PAGE_SIZE * keg->uk_ppera - keg->uk_rsize < shsize) {
/*
* We can't do OFFPAGE if we're internal, in which case
* we need an extra page per allocation to contain the
* slab header.
*/
if ((keg->uk_flags & UMA_ZFLAG_INTERNAL) == 0)
keg->uk_flags |= UMA_ZONE_OFFPAGE;
else
keg->uk_ppera++;
}
Make UMA to not blindly force offpage slab header allocation for large (> PAGE_SIZE) zones. If zone is not multiple to PAGE_SIZE, there may be enough space for the header at the last page, so we may avoid extra header memory allocation and hash table update/lookup. ZFS creates bunch of odd-sized UMA zones (5120, 6144, 7168, 10240, 14336). This change gives good use to at least some of otherwise lost memory there. Reviewed by: avg
2013-11-27 20:56:10 +00:00
}
if ((keg->uk_flags & UMA_ZONE_OFFPAGE) &&
(keg->uk_flags & UMA_ZONE_VTOSLAB) == 0)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_flags |= UMA_ZONE_HASH;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void
keg_cachespread_init(uma_keg_t keg)
{
int alignsize;
int trailer;
int pages;
int rsize;
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0,
("%s: Cannot cachespread-init a UMA_ZONE_PCPU keg", __func__));
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
alignsize = keg->uk_align + 1;
rsize = keg->uk_size;
/*
* We want one item to start on every align boundary in a page. To
* do this we will span pages. We will also extend the item by the
* size of align if it is an even multiple of align. Otherwise, it
* would fall on the same boundary every time.
*/
if (rsize & keg->uk_align)
rsize = (rsize & ~keg->uk_align) + alignsize;
if ((rsize & alignsize) == 0)
rsize += alignsize;
trailer = rsize - keg->uk_size;
pages = (rsize * (PAGE_SIZE / alignsize)) / PAGE_SIZE;
pages = MIN(pages, (128 * 1024) / PAGE_SIZE);
keg->uk_rsize = rsize;
keg->uk_ppera = pages;
keg->uk_ipers = ((pages * PAGE_SIZE) + trailer) / rsize;
keg->uk_flags |= UMA_ZONE_OFFPAGE | UMA_ZONE_VTOSLAB;
After r251709, avoid a clang 3.4 warning about an unused static const variable (uma_max_ipers), when asserts are disabled. Reviewed by: glebius MFC after: 3 days
2014-02-14 17:47:18 +00:00
KASSERT(keg->uk_ipers <= SLAB_SETSIZE,
Fix function name in keg_cachespread_init() assert.
2012-08-26 09:54:11 +00:00
("%s: keg->uk_ipers too high(%d) increase max_ipers", __func__,
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_ipers));
}
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
/*
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
* Keg header ctor. This initializes all fields, locks, etc. And inserts
* the keg onto the global keg list.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Arguments/Returns follow uma_ctor specifications
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
* udata Actually uma_kctor_args
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
static int
keg_ctor(void *mem, int size, void *udata, int flags)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
struct uma_kctor_args *arg = udata;
uma_keg_t keg = mem;
uma_zone_t zone;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
bzero(keg, size);
keg->uk_size = arg->size;
keg->uk_init = arg->uminit;
keg->uk_fini = arg->fini;
keg->uk_align = arg->align;
keg->uk_free = 0;
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
keg->uk_reserve = 0;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_pages = 0;
keg->uk_flags = arg->flags;
keg->uk_slabzone = NULL;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/*
* The master zone is passed to us at keg-creation time.
*/
zone = arg->zone;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_name = zone->uz_name;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Introduce the new M_NOVM option which tells uma to only check the currently allocated slabs and bucket caches for free items. It will not go ask the vm for pages. This differs from M_NOWAIT in that it not only doesn't block, it doesn't even ask. - Add a new zcreate option ZONE_VM, that sets the BUCKETCACHE zflag. This tells uma that it should only allocate buckets out of the bucket cache, and not from the VM. It does this by using the M_NOVM option to zalloc when getting a new bucket. This is so that the VM doesn't recursively enter itself while trying to allocate buckets for vm_map_entry zones. If there are already allocated buckets when we get here we'll still use them but otherwise we'll skip it. - Use the ZONE_VM flag on vm map entries and pv entries on x86.
2002-06-17 22:02:41 +00:00
if (arg->flags & UMA_ZONE_VM)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_flags |= UMA_ZFLAG_CACHEONLY;
if (arg->flags & UMA_ZONE_ZINIT)
keg->uk_init = zero_init;
- Introduce the new M_NOVM option which tells uma to only check the currently allocated slabs and bucket caches for free items. It will not go ask the vm for pages. This differs from M_NOWAIT in that it not only doesn't block, it doesn't even ask. - Add a new zcreate option ZONE_VM, that sets the BUCKETCACHE zflag. This tells uma that it should only allocate buckets out of the bucket cache, and not from the VM. It does this by using the M_NOVM option to zalloc when getting a new bucket. This is so that the VM doesn't recursively enter itself while trying to allocate buckets for vm_map_entry zones. If there are already allocated buckets when we get here we'll still use them but otherwise we'll skip it. - Use the ZONE_VM flag on vm map entries and pv entries on x86.
2002-06-17 22:02:41 +00:00
Remove UMA_ZONE_REFCNT feature, now unused. Blessed by: jeff
2016-03-01 00:33:32 +00:00
if (arg->flags & UMA_ZONE_MALLOC)
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_flags |= UMA_ZONE_VTOSLAB;
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
if (arg->flags & UMA_ZONE_PCPU)
#ifdef SMP
keg->uk_flags |= UMA_ZONE_OFFPAGE;
#else
keg->uk_flags &= ~UMA_ZONE_PCPU;
#endif
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
if (keg->uk_flags & UMA_ZONE_CACHESPREAD) {
keg_cachespread_init(keg);
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
} else {
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
if (keg->uk_size > (UMA_SLAB_SIZE - sizeof(struct uma_slab)))
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_large_init(keg);
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
else
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_small_init(keg);
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
}
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
Remove UMA_ZONE_REFCNT feature, now unused. Blessed by: jeff
2016-03-01 00:33:32 +00:00
if (keg->uk_flags & UMA_ZONE_OFFPAGE)
keg->uk_slabzone = slabzone;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
/*
* If we haven't booted yet we need allocations to go through the
* startup cache until the vm is ready.
*/
When we are in UMA_STARTUP use startup_alloc() for any zone, not for internal zones only. This allows to create new zones at early stages of boot, without need to mark them as internal to UMA, which isn't always true. Reviewed by: alc
2017-06-08 21:33:19 +00:00
if (booted < UMA_STARTUP2)
keg->uk_allocf = startup_alloc;
- Fix MD_SMALL_ALLOC on architectures that support it. Define a new alloc function, startup_alloc(), that is used for single page allocations prior to the VM starting up. If it is used after the VM startups up, it replaces the zone's allocf pointer with either page_alloc() or uma_small_alloc() where appropriate. Pointy hat to: me Tested by: phk/amd64, me/x86
2003-09-21 07:39:16 +00:00
#ifdef UMA_MD_SMALL_ALLOC
When we are in UMA_STARTUP use startup_alloc() for any zone, not for internal zones only. This allows to create new zones at early stages of boot, without need to mark them as internal to UMA, which isn't always true. Reviewed by: alc
2017-06-08 21:33:19 +00:00
else if (keg->uk_ppera == 1)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_allocf = uma_small_alloc;
When we are in UMA_STARTUP use startup_alloc() for any zone, not for internal zones only. This allows to create new zones at early stages of boot, without need to mark them as internal to UMA, which isn't always true. Reviewed by: alc
2017-06-08 21:33:19 +00:00
#endif
else
keg->uk_allocf = page_alloc;
#ifdef UMA_MD_SMALL_ALLOC
if (keg->uk_ppera == 1)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_freef = uma_small_free;
When we are in UMA_STARTUP use startup_alloc() for any zone, not for internal zones only. This allows to create new zones at early stages of boot, without need to mark them as internal to UMA, which isn't always true. Reviewed by: alc
2017-06-08 21:33:19 +00:00
else
Correct an error in r222163. Unless UMA_MD_SMALL_ALLOC is defined, startup_alloc() must be used until uma_startup2() is called. Reported by: jh
2011-05-22 17:46:16 +00:00
#endif
When we are in UMA_STARTUP use startup_alloc() for any zone, not for internal zones only. This allows to create new zones at early stages of boot, without need to mark them as internal to UMA, which isn't always true. Reviewed by: alc
2017-06-08 21:33:19 +00:00
keg->uk_freef = page_free;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/*
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
* Initialize keg's lock
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
*/
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK_INIT(keg, (arg->flags & UMA_ZONE_MTXCLASS));
Add a new zone flag UMA_ZONE_MTXCLASS. This puts the zone in it's own mutex class. Currently this is only used for kmapentzone because kmapents are are potentially allocated when freeing memory. This is not dangerous though because no other allocations will be done while holding the kmapentzone lock.
2002-04-29 23:45:41 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* If we're putting the slab header in the actual page we need to
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
* figure out where in each page it goes. This calculates a right
Correct typos, mostly s/ a / an / where appropriate. Some whitespace cleanup, especially in troff files.
2003-01-01 18:49:04 +00:00
* justified offset into the memory on an ALIGN_PTR boundary.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (!(keg->uk_flags & UMA_ZONE_OFFPAGE)) {
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
u_int totsize;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* Size of the slab struct and free list */
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
totsize = sizeof(struct uma_slab);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
if (totsize & UMA_ALIGN_PTR)
totsize = (totsize & ~UMA_ALIGN_PTR) +
(UMA_ALIGN_PTR + 1);
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - totsize;
Rework the way slab header storage space is calculated in UMA. - zone_large_init() stays pretty much the same. - zone_small_init() will try to stash the slab header in the slab page being allocated if the amount of calculated wasted space is less than UMA_MAX_WASTE (for both the UMA_ZONE_REFCNT case and regular case). If the amount of wasted space is >= UMA_MAX_WASTE, then UMA_ZONE_OFFPAGE will be set and the slab header will be allocated separately for better use of space. - uma_startup() calculates the maximum ipers required in offpage slabs (so that the offpage slab header zone(s) can be sized accordingly). The algorithm used to calculate this replaces the old calculation (which only happened to work coincidentally). We now iterate over possible object sizes, starting from the smallest one, until we determine that wastedspace calculated in zone_small_init() might end up being greater than UMA_MAX_WASTE, at which point we use the found object size to compute the maximum possible ipers. The reason this works is because: - wastedspace versus objectsize is a see-saw function with local minima all equal to zero and local maxima growing directly proportioned to objectsize. This implies that for objects up to or equal a certain objectsize, the see-saw remains entirely below UMA_MAX_WASTE, so for those objectsizes it is impossible to ever go OFFPAGE for slab headers. - ipers (items-per-slab) versus objectsize is an inversely proportional function which falls off very quickly (very large for small objectsizes). - To determine the maximum ipers we'll ever need from OFFPAGE slab headers we first find the largest objectsize for which we are guaranteed to not go offpage for and use it to compute ipers (as though we were offpage). Since the only objectsizes allowed to go offpage are bigger than the found objectsize, and since ipers vs objectsize is inversely proportional (and monotonically decreasing), then we are guaranteed that the ipers computed is always >= what we will ever need in offpage slab headers. - Define UMA_FRITM_SZ and UMA_FRITMREF_SZ to be the actual (possibly padded) size of each freelist index so that offset calculations are fixed. This might fix weird data corruption problems and certainly allows ARM to now boot to at least single-user (via simulator). Tested on i386 UP by me. Tested on sparc64 SMP by fenner. Tested on ARM simulator to single-user by cognet.
2004-07-29 15:25:40 +00:00
/*
* The only way the following is possible is if with our
* UMA_ALIGN_PTR adjustments we are now bigger than
* UMA_SLAB_SIZE. I haven't checked whether this is
* mathematically possible for all cases, so we make
* sure here anyway.
*/
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
totsize = keg->uk_pgoff + sizeof(struct uma_slab);
Merge from projects/counters: UMA_ZONE_PCPU zones. These zones have slab size == sizeof(struct pcpu), but request from VM enough pages to fit (uk_slabsize * mp_ncpus). An item allocated from such zone would have a separate twin for each CPU in the system, and these twins are at a distance of sizeof(struct pcpu) from each other. This magic value of distance would allow us to make some optimizations later. To address private item from a CPU simple arithmetics should be used: item = (type *)((char *)base + sizeof(struct pcpu) * curcpu) These arithmetics are available as zpcpu_get() macro in pcpu.h. To introduce non-page size slabs a new field had been added to uma_keg uk_slabsize. This shifted some frequently used fields of uma_keg to the fourth cache line on amd64. To mitigate this pessimization, uma_keg fields were a bit rearranged and least frequently used uk_name and uk_link moved down to the fourth cache line. All other fields, that are dereferenced frequently fit into first three cache lines. Sponsored by: Nginx, Inc.
2013-04-08 19:10:45 +00:00
if (totsize > PAGE_SIZE * keg->uk_ppera) {
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
printf("zone %s ipers %d rsize %d size %d\n",
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
zone->uz_name, keg->uk_ipers, keg->uk_rsize,
keg->uk_size);
Add support for UMA_SLAB_KERNEL to page_free(). (While I'm here remove an unnecessary newline character from the end of two panic messages.)
2009-06-18 07:27:11 +00:00
panic("UMA slab won't fit.");
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
}
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_flags & UMA_ZONE_HASH)
hash_alloc(&keg->uk_hash);
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR5(KTR_UMA, "keg_ctor %p zone %s(%p) out %d free %d\n",
keg, zone->uz_name, zone,
uma: fix pages <-> items conversions at several places Those places were not taking into account uk_ppera. At present one allocation is always used by one slab, so uk_ppera must be used to convert between pages and slabs. uk_ipers is used to convert between slabs and items. MFC after: 1 month (if ever)
2017-03-11 16:43:38 +00:00
(keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free,
keg->uk_free);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wlock(&uma_rwlock);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wunlock(&uma_rwlock);
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
return (0);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
/*
* Zone header ctor. This initializes all fields, locks, etc.
*
* Arguments/Returns follow uma_ctor specifications
* udata Actually uma_zctor_args
*/
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
static int
zone_ctor(void *mem, int size, void *udata, int flags)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
{
struct uma_zctor_args *arg = udata;
uma_zone_t zone = mem;
uma_zone_t z;
uma_keg_t keg;
bzero(zone, size);
zone->uz_name = arg->name;
zone->uz_ctor = arg->ctor;
zone->uz_dtor = arg->dtor;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_slab = zone_fetch_slab;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
zone->uz_init = NULL;
zone->uz_fini = NULL;
zone->uz_allocs = 0;
In addition to tracking allocs in the zone, also track frees. Add a zone free counter, as well as a cache free counter. MFC after: 1 week
2005-07-14 16:17:21 +00:00
zone->uz_frees = 0;
Track UMA(9) allocation failures by zone, and export via sysctl. Requested by: victor cruceru <victor dot cruceru at gmail dot com> MFC after: 1 week
2005-07-15 23:34:39 +00:00
zone->uz_fails = 0;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
zone->uz_sleeps = 0;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
zone->uz_count = 0;
Implement soft pressure on UMA cache bucket sizes. Every time system detects low memory condition decrease bucket sizes for each zone by one item. As result, higher memory pressure will push to smaller bucket sizes and so smaller per-CPU caches and so more efficient memory use. Before this change there was no force to oppose buckets growth as result of practically inevitable zone lock conflicts, and after some run time per-CPU caches could consume enough RAM to kill the system.
2013-11-19 10:05:53 +00:00
zone->uz_count_min = 0;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_flags = 0;
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
zone->uz_warning = NULL;
timevalclear(&zone->uz_ratecheck);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = arg->keg;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
ZONE_LOCK_INIT(zone, (arg->flags & UMA_ZONE_MTXCLASS));
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
/*
* This is a pure cache zone, no kegs.
*/
if (arg->import) {
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
if (arg->flags & UMA_ZONE_VM)
arg->flags |= UMA_ZFLAG_CACHEONLY;
zone->uz_flags = arg->flags;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
zone->uz_size = arg->size;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone->uz_import = arg->import;
zone->uz_release = arg->release;
zone->uz_arg = arg->arg;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
zone->uz_lockptr = &zone->uz_lock;
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wlock(&uma_rwlock);
- Add bucket size column to `show uma` DDB command. - Add `show umacache` command to show alike stats for cache-only UMA zones.
2013-11-28 19:20:49 +00:00
LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wunlock(&uma_rwlock);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
goto out;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
}
/*
* Use the regular zone/keg/slab allocator.
*/
zone->uz_import = (uma_import)zone_import;
zone->uz_release = (uma_release)zone_release;
zone->uz_arg = zone;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (arg->flags & UMA_ZONE_SECONDARY) {
KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
zone->uz_init = arg->uminit;
zone->uz_fini = arg->fini;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
zone->uz_lockptr = &keg->uk_lock;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_flags |= UMA_ZONE_SECONDARY;
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wlock(&uma_rwlock);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
ZONE_LOCK(zone);
LIST_FOREACH(z, &keg->uk_zones, uz_link) {
if (LIST_NEXT(z, uz_link) == NULL) {
LIST_INSERT_AFTER(z, zone, uz_link);
break;
}
}
ZONE_UNLOCK(zone);
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wunlock(&uma_rwlock);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
} else if (keg == NULL) {
if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
arg->align, arg->flags)) == NULL)
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
return (ENOMEM);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
} else {
struct uma_kctor_args karg;
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
int error;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/* We should only be here from uma_startup() */
karg.size = arg->size;
karg.uminit = arg->uminit;
karg.fini = arg->fini;
karg.align = arg->align;
karg.flags = arg->flags;
karg.zone = zone;
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
flags);
if (error)
return (error);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
/*
* Link in the first keg.
*/
zone->uz_klink.kl_keg = keg;
LIST_INSERT_HEAD(&zone->uz_kegs, &zone->uz_klink, kl_link);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
zone->uz_lockptr = &keg->uk_lock;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_size = keg->uk_size;
zone->uz_flags |= (keg->uk_flags &
(UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Some internal zones don't have room allocated for the per cpu
* caches. If we're internal, bail out here.
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_flags & UMA_ZFLAG_INTERNAL) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
("Secondary zone requested UMA_ZFLAG_INTERNAL"));
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
return (0);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
out:
if ((arg->flags & UMA_ZONE_MAXBUCKET) == 0)
zone->uz_count = bucket_select(zone->uz_size);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
else
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
zone->uz_count = BUCKET_MAX;
Implement soft pressure on UMA cache bucket sizes. Every time system detects low memory condition decrease bucket sizes for each zone by one item. As result, higher memory pressure will push to smaller bucket sizes and so smaller per-CPU caches and so more efficient memory use. Before this change there was no force to oppose buckets growth as result of practically inevitable zone lock conflicts, and after some run time per-CPU caches could consume enough RAM to kill the system.
2013-11-19 10:05:53 +00:00
zone->uz_count_min = zone->uz_count;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
return (0);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
/*
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
* Keg header dtor. This frees all data, destroys locks, frees the hash
* table and removes the keg from the global list.
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
*
* Arguments/Returns follow uma_dtor specifications
* udata unused
*/
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
static void
keg_dtor(void *arg, int size, void *udata)
{
uma_keg_t keg;
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg = (uma_keg_t)arg;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_LOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_free != 0) {
In keg_dtor(), print out the keg name in the "Freed UMA keg was not empty" message printed to the console. This makes it easier to track down the source of certain memory leaks. Suggested by: adrian
2013-11-29 08:04:45 +00:00
printf("Freed UMA keg (%s) was not empty (%d items). "
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
" Lost %d pages of memory.\n",
In keg_dtor(), print out the keg name in the "Freed UMA keg was not empty" message printed to the console. This makes it easier to track down the source of certain memory leaks. Suggested by: adrian
2013-11-29 08:04:45 +00:00
keg->uk_name ? keg->uk_name : "",
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_free, keg->uk_pages);
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_UNLOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
hash_free(&keg->uk_hash);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KEG_LOCK_FINI(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
/*
* Zone header dtor.
*
* Arguments/Returns follow uma_dtor specifications
* udata unused
*/
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
static void
zone_dtor(void *arg, int size, void *udata)
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_klink_t klink;
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
uma_zone_t zone;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
zone = (uma_zone_t)arg;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
cache_drain(zone);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wlock(&uma_rwlock);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
LIST_REMOVE(zone, uz_link);
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wunlock(&uma_rwlock);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
/*
* XXX there are some races here where
* the zone can be drained but zone lock
* released and then refilled before we
* remove it... we dont care for now
*/
zone_drain_wait(zone, M_WAITOK);
/*
* Unlink all of our kegs.
*/
while ((klink = LIST_FIRST(&zone->uz_kegs)) != NULL) {
klink->kl_keg = NULL;
LIST_REMOVE(klink, kl_link);
if (klink == &zone->uz_klink)
continue;
free(klink, M_TEMP);
}
/*
* We only destroy kegs from non secondary zones.
*/
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (keg != NULL && (zone->uz_flags & UMA_ZONE_SECONDARY) == 0) {
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wlock(&uma_rwlock);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_REMOVE(keg, uk_link);
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_wunlock(&uma_rwlock);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(kegs, keg, NULL, SKIP_NONE);
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
}
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
ZONE_LOCK_FINI(zone);
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
}
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Traverses every zone in the system and calls a callback
*
* Arguments:
* zfunc A pointer to a function which accepts a zone
* as an argument.
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
*
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
* Returns:
* Nothing
*/
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
static void
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
zone_foreach(void (*zfunc)(uma_zone_t))
{
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
uma_zone_t zone;
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_rlock(&uma_rwlock);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_FOREACH(keg, &uma_kegs, uk_link) {
LIST_FOREACH(zone, &keg->uk_zones, uz_link)
zfunc(zone);
}
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_runlock(&uma_rwlock);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/* Public functions */
/* See uma.h */
void
Simplify boot pages management in UMA. It is simply a contigous virtual memory pointer and number of pages. There is no need to build a linked list here. Just increment pointer and decrement counter. The only functional difference to old allocator is that before we gave pages from topmost and down to lowest, and now we give them in normal ascending order. While here remove padalign from a mutex that is unused at runtime. Reviewed by: alc
2017-06-01 18:26:57 +00:00
uma_startup(void *mem, int npages)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
struct uma_zctor_args args;
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_init(&uma_rwlock, "UMA lock");
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/* "manually" create the initial zone */
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
memset(&args, 0, sizeof(args));
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.name = "UMA Kegs";
args.size = sizeof(struct uma_keg);
args.ctor = keg_ctor;
args.dtor = keg_dtor;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
args.uminit = zero_init;
args.fini = NULL;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.keg = &masterkeg;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
args.align = 32 - 1;
- Fix the silly flag situation in UMA. Remove redundant ZFLAG/ZONE flags by accepting the user supplied flags directly. Previously this was not done so that flags for the same field would not be defined in two different files. Add comments in each header instructing future developers on how now to shoot their feet. - Fix a test for !OFFPAGE which should have been a test for HASH. This would have caused a panic if we had ever destructed a malloc zone. This also opens up the possibility that other zones could use the vsetobj() method rather than a hash.
2003-09-19 08:37:44 +00:00
args.flags = UMA_ZFLAG_INTERNAL;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* The initial zone has no Per cpu queues so it's smaller */
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
zone_ctor(kegs, sizeof(struct uma_zone), &args, M_WAITOK);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Introduce a new lock for the purpose of synchronizing access to the UMA boot pages. Disable recursion on the general UMA lock now that startup_alloc() no longer uses it. Eliminate the variable uma_boot_free. It serves no purpose. Note: This change eliminates a lock-order reversal between a system map mutex and the UMA lock. See http://sources.zabbadoz.net/freebsd/lor.html#109 for details. MFC after: 3 days
2005-09-09 06:03:08 +00:00
mtx_init(&uma_boot_pages_mtx, "UMA boot pages", NULL, MTX_DEF);
Simplify boot pages management in UMA. It is simply a contigous virtual memory pointer and number of pages. There is no need to build a linked list here. Just increment pointer and decrement counter. The only functional difference to old allocator is that before we gave pages from topmost and down to lowest, and now we give them in normal ascending order. While here remove padalign from a mutex that is unused at runtime. Reviewed by: alc
2017-06-01 18:26:57 +00:00
bootmem = mem;
boot_pages = npages;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.name = "UMA Zones";
args.size = sizeof(struct uma_zone) +
Rework r281162. Indeed, the flexible array member is preferable here. Suggested by: Justin T. Gibbs MFC after: 3 days
2015-04-12 06:21:58 +00:00
(sizeof(struct uma_cache) * (mp_maxid + 1));
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.ctor = zone_ctor;
args.dtor = zone_dtor;
args.uminit = zero_init;
args.fini = NULL;
args.keg = NULL;
args.align = 32 - 1;
args.flags = UMA_ZFLAG_INTERNAL;
/* The initial zone has no Per cpu queues so it's smaller */
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
zone_ctor(zones, sizeof(struct uma_zone), &args, M_WAITOK);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* Now make a zone for slab headers */
slabzone = uma_zcreate("UMA Slabs",
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
sizeof(struct uma_slab),
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
NULL, NULL, NULL, NULL,
- Fix the silly flag situation in UMA. Remove redundant ZFLAG/ZONE flags by accepting the user supplied flags directly. Previously this was not done so that flags for the same field would not be defined in two different files. Add comments in each header instructing future developers on how now to shoot their feet. - Fix a test for !OFFPAGE which should have been a test for HASH. This would have caused a panic if we had ever destructed a malloc zone. This also opens up the possibility that other zones could use the vsetobj() method rather than a hash.
2003-09-19 08:37:44 +00:00
UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
hashzone = uma_zcreate("UMA Hash",
sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
NULL, NULL, NULL, NULL,
- Fix the silly flag situation in UMA. Remove redundant ZFLAG/ZONE flags by accepting the user supplied flags directly. Previously this was not done so that flags for the same field would not be defined in two different files. Add comments in each header instructing future developers on how now to shoot their feet. - Fix a test for !OFFPAGE which should have been a test for HASH. This would have caused a panic if we had ever destructed a malloc zone. This also opens up the possibility that other zones could use the vsetobj() method rather than a hash.
2003-09-19 08:37:44 +00:00
UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
bucket_init();
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
1. Prior to r214782, UMA did not support multipage allocations before uma_startup2() was called. Thus, setting the variable "booted" to true in uma_startup() was ok on machines with UMA_MD_SMALL_ALLOC defined, because any allocations made after uma_startup() but before uma_startup2() could be satisfied by uma_small_alloc(). Now, however, some multipage allocations are necessary before uma_startup2() just to allocate zone structures on machines with a large number of processors. Thus, a Boolean can no longer effectively describe the state of the UMA allocator. Instead, make "booted" have three values to describe how far initialization has progressed. This allows multipage allocations to continue using startup_alloc() until uma_startup2(), but single-page allocations may begin using uma_small_alloc() after uma_startup(). 2. With the aforementioned change, only a modest increase in boot pages is necessary to boot UMA on a large number of processors. 3. Retire UMA_MD_SMALL_ALLOC_NEEDS_VM. It has only been used between r182028 and r204128. Reviewed by: attilio [1], nwhitehorn [3] Tested by: sbruno
2011-05-21 17:43:43 +00:00
booted = UMA_STARTUP;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/* see uma.h */
void
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
uma_startup2(void)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
1. Prior to r214782, UMA did not support multipage allocations before uma_startup2() was called. Thus, setting the variable "booted" to true in uma_startup() was ok on machines with UMA_MD_SMALL_ALLOC defined, because any allocations made after uma_startup() but before uma_startup2() could be satisfied by uma_small_alloc(). Now, however, some multipage allocations are necessary before uma_startup2() just to allocate zone structures on machines with a large number of processors. Thus, a Boolean can no longer effectively describe the state of the UMA allocator. Instead, make "booted" have three values to describe how far initialization has progressed. This allows multipage allocations to continue using startup_alloc() until uma_startup2(), but single-page allocations may begin using uma_small_alloc() after uma_startup(). 2. With the aforementioned change, only a modest increase in boot pages is necessary to boot UMA on a large number of processors. 3. Retire UMA_MD_SMALL_ALLOC_NEEDS_VM. It has only been used between r182028 and r204128. Reviewed by: attilio [1], nwhitehorn [3] Tested by: sbruno
2011-05-21 17:43:43 +00:00
booted = UMA_STARTUP2;
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
bucket_enable();
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
sx_init(&uma_drain_lock, "umadrain");
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/*
* Initialize our callout handle
*
*/
static void
uma_startup3(void)
{
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CALLOUT_MPSAFE has lost its meaning since r141428, i.e., for more than ten years for head. However, it is continuously misused as the mpsafe argument for callout_init(9). Deprecate the flag and clean up callout_init() calls to make them more consistent. Differential Revision: https://reviews.freebsd.org/D2613 Reviewed by: jhb MFC after: 2 weeks
2015-05-22 17:05:21 +00:00
callout_init(&uma_callout, 1);
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
callout_reset(&uma_callout, UMA_TIMEOUT * hz, uma_timeout, NULL);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static uma_keg_t
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
int align, uint32_t flags)
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
{
struct uma_kctor_args args;
args.size = size;
args.uminit = uminit;
args.fini = fini;
Add uma_set_align() interface, which will be called at most once during boot by MD code to indicated detected alignment preference. Rather than cache alignment being encoded in UMA consumers by defining a global alignment value of (16 - 1) in UMA_ALIGN_CACHE, UMA_ALIGN_CACHE is now a special value (-1) that causes UMA to look at registered alignment. If no preferred alignment has been selected by MD code, a default alignment of (16 - 1) will be used. Currently, no hardware platforms specify alignment; architecture maintainers will need to modify MD startup code to specify an alignment if desired. This must occur before initialization of UMA so that all UMA zones pick up the requested alignment. Reviewed by: jeff, alc Submitted by: attilio
2007-02-11 20:13:52 +00:00
args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.flags = flags;
args.zone = zone;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
return (zone_alloc_item(kegs, &args, M_WAITOK));
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
Add uma_set_align() interface, which will be called at most once during boot by MD code to indicated detected alignment preference. Rather than cache alignment being encoded in UMA consumers by defining a global alignment value of (16 - 1) in UMA_ALIGN_CACHE, UMA_ALIGN_CACHE is now a special value (-1) that causes UMA to look at registered alignment. If no preferred alignment has been selected by MD code, a default alignment of (16 - 1) will be used. Currently, no hardware platforms specify alignment; architecture maintainers will need to modify MD startup code to specify an alignment if desired. This must occur before initialization of UMA so that all UMA zones pick up the requested alignment. Reviewed by: jeff, alc Submitted by: attilio
2007-02-11 20:13:52 +00:00
/* See uma.h */
void
uma_set_align(int align)
{
if (align != UMA_ALIGN_CACHE)
uma_align_cache = align;
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* See uma.h */
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
uma_zone_t
Const-ify the zone name argument to uma_zcreate(9). MFC after: 3 days
2012-10-26 17:51:05 +00:00
uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uma_init uminit, uma_fini fini, int align, uint32_t flags)
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
struct uma_zctor_args args;
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
uma_zone_t res;
bool locked;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Assert that the align parameter to uma_zcreate() is valid. Reviewed by: kib MFC after: 1 week Sponsored by: DARPA / AFRL Differential Revision: https://reviews.freebsd.org/D10100
2017-04-04 16:26:46 +00:00
KASSERT(powerof2(align + 1), ("invalid zone alignment %d for \"%s\"",
align, name));
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* This stuff is essential for the zone ctor */
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
memset(&args, 0, sizeof(args));
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
args.name = name;
args.size = size;
args.ctor = ctor;
args.dtor = dtor;
args.uminit = uminit;
args.fini = fini;
If INVARIANTS is specified, add ctor/dtor to junk memory if they are unspecified... Submitted by: Suresh Gumpula at Netapp Differential Revision: https://reviews.freebsd.org/D2725
2015-06-25 20:44:46 +00:00
#ifdef INVARIANTS
/*
* If a zone is being created with an empty constructor and
* destructor, pass UMA constructor/destructor which checks for
* memory use after free.
*/
Don't trash memory from UMA_ZONE_NOFREE zones. Objects obtained from such zones are supposed to retain type stability, which was violated by aforementioned trashing. This is a follow-up to r284861. Discussed with: kib
2015-09-02 23:09:01 +00:00
if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOFREE))) &&
ctor == NULL && dtor == NULL && uminit == NULL && fini == NULL) {
If INVARIANTS is specified, add ctor/dtor to junk memory if they are unspecified... Submitted by: Suresh Gumpula at Netapp Differential Revision: https://reviews.freebsd.org/D2725
2015-06-25 20:44:46 +00:00
args.ctor = trash_ctor;
args.dtor = trash_dtor;
args.uminit = trash_init;
args.fini = trash_fini;
}
#endif
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
args.align = align;
args.flags = flags;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.keg = NULL;
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
if (booted < UMA_STARTUP2) {
locked = false;
} else {
sx_slock(&uma_drain_lock);
locked = true;
}
res = zone_alloc_item(zones, &args, M_WAITOK);
if (locked)
sx_sunlock(&uma_drain_lock);
return (res);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
/* See uma.h */
uma_zone_t
uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
uma_init zinit, uma_fini zfini, uma_zone_t master)
{
struct uma_zctor_args args;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t keg;
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
uma_zone_t res;
bool locked;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(master);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
memset(&args, 0, sizeof(args));
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.name = name;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
args.size = keg->uk_size;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
args.ctor = ctor;
args.dtor = dtor;
args.uminit = zinit;
args.fini = zfini;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
args.align = keg->uk_align;
args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
args.keg = keg;
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
if (booted < UMA_STARTUP2) {
locked = false;
} else {
sx_slock(&uma_drain_lock);
locked = true;
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
/* XXX Attaches only one keg of potentially many. */
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
res = zone_alloc_item(zones, &args, M_WAITOK);
if (locked)
sx_sunlock(&uma_drain_lock);
return (res);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
/* See uma.h */
uma_zone_t
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
uma_zcache_create(char *name, int size, uma_ctor ctor, uma_dtor dtor,
uma_init zinit, uma_fini zfini, uma_import zimport,
uma_release zrelease, void *arg, int flags)
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
{
struct uma_zctor_args args;
memset(&args, 0, sizeof(args));
args.name = name;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
args.size = size;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
args.ctor = ctor;
args.dtor = dtor;
args.uminit = zinit;
args.fini = zfini;
args.import = zimport;
args.release = zrelease;
args.arg = arg;
args.align = 0;
args.flags = flags;
return (zone_alloc_item(zones, &args, M_WAITOK));
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void
zone_lock_pair(uma_zone_t a, uma_zone_t b)
{
if (a < b) {
ZONE_LOCK(a);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
mtx_lock_flags(b->uz_lockptr, MTX_DUPOK);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
} else {
ZONE_LOCK(b);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
mtx_lock_flags(a->uz_lockptr, MTX_DUPOK);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
}
static void
zone_unlock_pair(uma_zone_t a, uma_zone_t b)
{
ZONE_UNLOCK(a);
ZONE_UNLOCK(b);
}
int
uma_zsecond_add(uma_zone_t zone, uma_zone_t master)
{
uma_klink_t klink;
uma_klink_t kl;
int error;
error = 0;
klink = malloc(sizeof(*klink), M_TEMP, M_WAITOK | M_ZERO);
zone_lock_pair(zone, master);
/*
* zone must use vtoslab() to resolve objects and must already be
* a secondary.
*/
if ((zone->uz_flags & (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY))
!= (UMA_ZONE_VTOSLAB | UMA_ZONE_SECONDARY)) {
error = EINVAL;
goto out;
}
/*
* The new master must also use vtoslab().
*/
if ((zone->uz_flags & UMA_ZONE_VTOSLAB) != UMA_ZONE_VTOSLAB) {
error = EINVAL;
goto out;
}
Remove UMA_ZONE_REFCNT feature, now unused. Blessed by: jeff
2016-03-01 00:33:32 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
/*
* The underlying object must be the same size. rsize
* may be different.
*/
if (master->uz_size != zone->uz_size) {
error = E2BIG;
goto out;
}
/*
* Put it at the end of the list.
*/
klink->kl_keg = zone_first_keg(master);
LIST_FOREACH(kl, &zone->uz_kegs, kl_link) {
if (LIST_NEXT(kl, kl_link) == NULL) {
LIST_INSERT_AFTER(kl, klink, kl_link);
break;
}
}
klink = NULL;
zone->uz_flags |= UMA_ZFLAG_MULTI;
zone->uz_slab = zone_fetch_slab_multi;
out:
zone_unlock_pair(zone, master);
if (klink != NULL)
free(klink, M_TEMP);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
return (error);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
/* See uma.h */
void
uma_zdestroy(uma_zone_t zone)
{
Further UMA statistics related changes: - Add a new uma_zfree_internal() flag, ZFREE_STATFREE, which causes it to to update the zone's uz_frees statistic. Previously, the statistic was updated unconditionally. - Use the flag in situations where a "real" free occurs: i.e., one where the caller is freeing an allocated item, to be differentiated from situations where uma_zfree_internal() is used to tear down the item during slab teardown in order to invoke its fini() method. Also use the flag when UMA is freeing its internal objects. - When exchanging a bucket with the zone from the per-CPU cache when freeing an item, flush cache statistics back to the zone (since the zone lock and critical section are both held) to match the allocation case. MFC after: 3 days
2005-07-20 18:47:42 +00:00
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
sx_slock(&uma_drain_lock);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(zones, zone, NULL, SKIP_NONE);
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
sx_sunlock(&uma_drain_lock);
Implement uma_zdestroy(). It's prototype changed slightly. I decided that I didn't like the wait argument and that if you were removing a zone it had better be empty. Also, I broke out part of hash_expand and made a seperate hash_free() for use in uma_zdestroy.
2002-04-08 04:48:58 +00:00
}
Replace manyinstances of VM_WAIT with blocking page allocation flags similar to the kernel memory allocator. This simplifies NUMA allocation because the domain will be known at wait time and races between failure and sleeping are eliminated. This also reduces boilerplate code and simplifies callers. A wait primitive is supplied for uma zones for similar reasons. This eliminates some non-specific VM_WAIT calls in favor of more explicit sleeps that may be satisfied without new pages. Reviewed by: alc, kib, markj Tested by: pho Sponsored by: Netflix, Dell/EMC Isilon
2017-11-08 02:39:37 +00:00
void
uma_zwait(uma_zone_t zone)
{
void *item;
item = uma_zalloc_arg(zone, NULL, M_WAITOK);
uma_zfree(zone, item);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* See uma.h */
void *
Move the implementation of M_ZERO into UMA so that it can be passed to uma_zalloc and friends. Remove this functionality from the malloc wrapper. Document this change in uma.h and adjust variable names in uma_core.
2002-04-30 04:26:34 +00:00
uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
void *item;
uma_cache_t cache;
uma_bucket_t bucket;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
int lockfail;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
int cpu;
Make the UMA harvesting go away completely if not wanted. Default to "not wanted". Provide and document the RANDOM_ENABLE_UMA option. Change RANDOM_FAST to RANDOM_UMA to clarify the harvesting. Remove RANDOM_DEBUG option, replace with SDT probes. These will be of use to folks measuring the harvesting effect when deciding whether to use RANDOM_ENABLE_UMA. Requested by: scottl and others. Approved by: so (/dev/random blanket) Differential Revision: https://reviews.freebsd.org/D3197
2015-08-22 12:59:05 +00:00
/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
This is the much-discussed major upgrade to the random(4) device, known to you all as /dev/random. This code has had an extensive rewrite and a good series of reviews, both by the author and other parties. This means a lot of code has been simplified. Pluggable structures for high-rate entropy generators are available, and it is most definitely not the case that /dev/random can be driven by only a hardware souce any more. This has been designed out of the device. Hardware sources are stirred into the CSPRNG (Yarrow, Fortuna) like any other entropy source. Pluggable modules may be written by third parties for additional sources. The harvesting structures and consequently the locking have been simplified. Entropy harvesting is done in a more general way (the documentation for this will follow). There is some GREAT entropy to be had in the UMA allocator, but it is disabled for now as messing with that is likely to annoy many people. The venerable (but effective) Yarrow algorithm, which is no longer supported by its authors now has an alternative, Fortuna. For now, Yarrow is retained as the default algorithm, but this may be changed using a kernel option. It is intended to make Fortuna the default algorithm for 11.0. Interested parties are encouraged to read ISBN 978-0-470-47424-2 "Cryptography Engineering" By Ferguson, Schneier and Kohno for Fortuna's gory details. Heck, read it anyway. Many thanks to Arthur Mesh who did early grunt work, and who got caught in the crossfire rather more than he deserved to. My thanks also to folks who helped me thresh this out on whiteboards and in the odd "Hallway track", or otherwise. My Nomex pants are on. Let the feedback commence! Reviewed by: trasz,des(partial),imp(partial?),rwatson(partial?) Approved by: so(des)
2014-10-30 21:21:53 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* This is the fast path allocation */
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR4(KTR_UMA, "uma_zalloc_arg thread %x zone %s(%p) flags %d",
curthread, zone->uz_name, zone, flags);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
Remove uma_zalloc_arg() hack, which coerced M_WAITOK to M_NOWAIT when allocations were made using improper flags in interrupt context. Replace with a simple WITNESS warning call. This restores the invariant that M_WAITOK allocations will always succeed or die horribly trying, which is relied on by many UMA consumers. MFC after: 3 weeks Discussed with: jhb
2007-01-10 21:04:43 +00:00
if (flags & M_WAITOK) {
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
"uma_zalloc_arg: zone \"%s\"", zone->uz_name);
In uma_zalloc_arg(), if we are performing a M_WAITOK allocation, ensure that td_intr_nesting_level is 0 (like malloc() does). Since malloc() calls uma we can probably remove the check in malloc() for this now. Also, perform an extra witness check in that case to make sure we don't hold any locks when performing a M_WAITOK allocation.
2002-05-20 17:54:48 +00:00
}
Don't make assertions about td_critnest when the scheduler is stopped. A panicking thread always executes with a critical section held, so any attempt to allocate or free memory while dumping will otherwise cause a second panic. This can occur, for example, if xpt_polled_action() completes non-dump I/O that was pending at the time of the panic. The fact that this can occur is itself a bug, but asserting in this case does little but reduce the reliability of kernel dumps. Suggested by: kib Reported by: pho
2015-12-11 20:05:07 +00:00
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
Consistently enforce the restriction against calling malloc/free when in a critical section. uma_zalloc_arg()/uma_zalloc_free() may acquire a sleepable lock on the zone. The malloc() family of functions may call uma_zalloc_arg() or uma_zalloc_free(). The malloc(9) man page currently claims that free() will never sleep. It also implies that the malloc() family of functions will not sleep when called with M_NOWAIT. However, it is more correct to say that these functions will not sleep indefinitely. Indeed, they may acquire a sleepable lock. However, a developer may overlook this restriction because the WITNESS check that catches attempts to call the malloc() family of functions within a critical section is inconsistenly applied. This change clarifies the language of the malloc(9) man page to clarify the restriction against calling the malloc() family of functions while in a critical section or holding a spin lock. It also adds KASSERTs at appropriate points to make the enforcement of this restriction more consistent. PR: 204633 Differential Revision: https://reviews.freebsd.org/D4197 Reviewed by: markj Approved by: gnn (mentor) Sponsored by: Juniper Networks
2015-11-19 14:04:53 +00:00
("uma_zalloc_arg: called with spinlock or critical section held"));
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
#ifdef DEBUG_MEMGUARD
if (memguard_cmp_zone(zone)) {
item = memguard_alloc(zone->uz_size, flags);
if (item != NULL) {
if (zone->uz_init != NULL &&
zone->uz_init(item, zone->uz_size, flags) != 0)
return (NULL);
if (zone->uz_ctor != NULL &&
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
zone->uz_ctor(item, zone->uz_size, udata,
flags) != 0) {
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
zone->uz_fini(item, zone->uz_size);
return (NULL);
}
return (item);
}
/* This is unfortunate but should not be fatal. */
}
#endif
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
/*
* If possible, allocate from the per-CPU cache. There are two
* requirements for safe access to the per-CPU cache: (1) the thread
* accessing the cache must not be preempted or yield during access,
* and (2) the thread must not migrate CPUs without switching which
* cache it accesses. We rely on a critical section to prevent
* preemption and migration. We release the critical section in
* order to acquire the zone mutex if we are unable to allocate from
* the current cache; when we re-acquire the critical section, we
* must detect and handle migration if it has occurred.
*/
critical_enter();
cpu = curcpu;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
cache = &zone->uz_cpu[cpu];
zalloc_start:
bucket = cache->uc_allocbucket;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (bucket != NULL && bucket->ub_cnt > 0) {
bucket->ub_cnt--;
item = bucket->ub_bucket[bucket->ub_cnt];
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#ifdef INVARIANTS
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
bucket->ub_bucket[bucket->ub_cnt] = NULL;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
#endif
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
cache->uc_allocs++;
critical_exit();
if (zone->uz_ctor != NULL &&
zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
atomic_add_long(&zone->uz_fails, 1);
zone_free_item(zone, item, udata, SKIP_DTOR);
return (NULL);
}
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
#ifdef INVARIANTS
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
uma_dbg_alloc(zone, NULL, item);
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
#endif
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (flags & M_ZERO)
Make M_ZERO flag work correctly on UMA_ZONE_PCPU zones. Sponsored by: Nginx, Inc.
2014-02-10 19:48:26 +00:00
uma_zero_item(item, zone);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
return (item);
}
/*
* We have run out of items in our alloc bucket.
* See if we can switch with our free bucket.
*/
bucket = cache->uc_freebucket;
if (bucket != NULL && bucket->ub_cnt > 0) {
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR2(KTR_UMA,
"uma_zalloc: zone %s(%p) swapping empty with alloc",
zone->uz_name, zone);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
cache->uc_freebucket = cache->uc_allocbucket;
cache->uc_allocbucket = bucket;
goto zalloc_start;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* Discard any empty allocation bucket while we hold no locks.
*/
bucket = cache->uc_allocbucket;
cache->uc_allocbucket = NULL;
critical_exit();
if (bucket != NULL)
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_free(zone, bucket, udata);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/* Short-circuit for zones without buckets and low memory. */
if (zone->uz_count == 0 || bucketdisable)
goto zalloc_item;
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
/*
* Attempt to retrieve the item from the per-CPU cache has failed, so
* we must go back to the zone. This requires the zone lock, so we
* must drop the critical section, then re-acquire it when we go back
* to the cache. Since the critical section is released, we may be
* preempted or migrate. As such, make sure not to maintain any
* thread-local state specific to the cache from prior to releasing
* the critical section.
*/
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
lockfail = 0;
if (ZONE_TRYLOCK(zone) == 0) {
/* Record contention to size the buckets. */
ZONE_LOCK(zone);
lockfail = 1;
}
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
critical_enter();
cpu = curcpu;
cache = &zone->uz_cpu[cpu];
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* Since we have locked the zone we may as well send back our stats.
*/
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
atomic_add_long(&zone->uz_frees, cache->uc_frees);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
cache->uc_allocs = 0;
In addition to tracking allocs in the zone, also track frees. Add a zone free counter, as well as a cache free counter. MFC after: 1 week
2005-07-14 16:17:21 +00:00
cache->uc_frees = 0;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/* See if we lost the race to fill the cache. */
if (cache->uc_allocbucket != NULL) {
ZONE_UNLOCK(zone);
goto zalloc_start;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* Check the zone's cache of buckets.
*/
if ((bucket = LIST_FIRST(&zone->uz_buckets)) != NULL) {
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
KASSERT(bucket->ub_cnt != 0,
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
("uma_zalloc_arg: Returning an empty bucket."));
LIST_REMOVE(bucket, ub_link);
cache->uc_allocbucket = bucket;
ZONE_UNLOCK(zone);
goto zalloc_start;
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
}
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
/* We are no longer associated with this CPU. */
critical_exit();
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* We bump the uz count when the cache size is insufficient to
* handle the working set.
*/
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
if (lockfail && zone->uz_count < BUCKET_MAX)
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
zone->uz_count++;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
ZONE_UNLOCK(zone);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
* Now lets just fill a bucket and put it on the free list. If that
sys/vm: minor spelling fixes in comments. No functional change.
2016-05-02 20:16:29 +00:00
* works we'll restart the allocation from the beginning and it
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
* will use the just filled bucket.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket = zone_alloc_bucket(zone, udata, flags);
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
zone->uz_name, zone, bucket);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (bucket != NULL) {
ZONE_LOCK(zone);
critical_enter();
cpu = curcpu;
cache = &zone->uz_cpu[cpu];
/*
* See if we lost the race or were migrated. Cache the
* initialized bucket to make this less likely or claim
* the memory directly.
*/
if (cache->uc_allocbucket == NULL)
cache->uc_allocbucket = bucket;
else
LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
ZONE_UNLOCK(zone);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
goto zalloc_start;
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
/*
* We may not be able to get a bucket so return an actual item.
*/
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
zalloc_item:
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
item = zone_alloc_item(zone, udata, flags);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
return (item);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
static uma_slab_t
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int flags)
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
{
uma_slab_t slab;
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
int reserve;
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
mtx_assert(&keg->uk_lock, MA_OWNED);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
slab = NULL;
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
reserve = 0;
if ((flags & M_USE_RESERVE) == 0)
reserve = keg->uk_reserve;
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
for (;;) {
/*
* Find a slab with some space. Prefer slabs that are partially
* used over those that are totally full. This helps to reduce
* fragmentation.
*/
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
if (keg->uk_free > reserve) {
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (!LIST_EMPTY(&keg->uk_part_slab)) {
slab = LIST_FIRST(&keg->uk_part_slab);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
} else {
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
slab = LIST_FIRST(&keg->uk_free_slab);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
LIST_REMOVE(slab, us_link);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_part_slab, slab,
us_link);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
MPASS(slab->us_keg == keg);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
return (slab);
}
/*
* M_NOVM means don't ask at all!
*/
if (flags & M_NOVM)
break;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (keg->uk_maxpages && keg->uk_pages >= keg->uk_maxpages) {
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_flags |= UMA_ZFLAG_FULL;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
/*
* If this is not a multi-zone, set the FULL bit.
* Otherwise slab_multi() takes care of it.
*/
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
if ((zone->uz_flags & UMA_ZFLAG_MULTI) == 0) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_flags |= UMA_ZFLAG_FULL;
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
zone_log_warning(zone);
Add a safety net to reclaim mbufs when one of the mbuf zones become exhausted. It is possible for a bug in the code (or, theoretically, even unusual network conditions) to exhaust all possible mbufs or mbuf clusters. When this occurs, things can grind to a halt fairly quickly. However, we currently do not call mb_reclaim() unless the entire system is experiencing a low-memory condition. While it is best to try to prevent exhaustion of one of the mbuf zones, it would also be useful to have a mechanism to attempt to recover from these situations by freeing "expendable" mbufs. This patch makes two changes: a) The patch adds a generic API to the UMA zone allocator to set a function that should be called when an allocation fails because the zone limit has been reached. Because of the way this function can be called, it really should do minimal work. b) The patch uses this API to try to free mbufs when an allocation fails from one of the mbuf zones because the zone limit has been reached. The function schedules a callout to run mb_reclaim(). Differential Revision: https://reviews.freebsd.org/D3864 Reviewed by: gnn Comments by: rrs, glebius MFC after: 2 weeks Sponsored by: Juniper Networks
2015-12-20 02:05:33 +00:00
zone_maxaction(zone);
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
}
- M_WAITOK is 0 and not a real flag. Test for this properly. Submitted by: tmm Pointy hat to: jeff
2003-01-20 01:32:56 +00:00
if (flags & M_NOWAIT)
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
break;
Add missing sleep stat increase PR: kern/168211 Submitted by: linimon Reviewed by: alc Approved by: cperciva MFC after: 3 days
2012-07-07 17:46:11 +00:00
zone->uz_sleeps++;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
msleep(keg, &keg->uk_lock, PVM, "keglimit", 0);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
continue;
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
slab = keg_alloc_slab(keg, zone, flags);
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
/*
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
* If we got a slab here it's safe to mark it partially used
* and return. We assume that the caller is going to remove
* at least one item.
*/
if (slab) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
MPASS(slab->us_keg == keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
return (slab);
}
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
/*
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
* We might not have been able to get a slab but another cpu
* could have while we were unlocked. Check again before we
* fail.
*/
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
flags |= M_NOVM;
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
return (slab);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static uma_slab_t
zone_fetch_slab(uma_zone_t zone, uma_keg_t keg, int flags)
{
uma_slab_t slab;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
if (keg == NULL) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
for (;;) {
slab = keg_fetch_slab(keg, zone, flags);
if (slab)
return (slab);
if (flags & (M_NOWAIT | M_NOVM))
break;
}
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
return (NULL);
}
/*
* uma_zone_fetch_slab_multi: Fetches a slab from one available keg. Returns
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
* with the keg locked. On NULL no lock is held.
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
*
* The last pointer is used to seed the search. It is not required.
*/
static uma_slab_t
zone_fetch_slab_multi(uma_zone_t zone, uma_keg_t last, int rflags)
{
uma_klink_t klink;
uma_slab_t slab;
uma_keg_t keg;
int flags;
int empty;
int full;
/*
* Don't wait on the first pass. This will skip limit tests
* as well. We don't want to block if we can find a provider
* without blocking.
*/
flags = (rflags & ~M_WAITOK) | M_NOWAIT;
/*
* Use the last slab allocated as a hint for where to start
* the search.
*/
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
if (last != NULL) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
slab = keg_fetch_slab(last, zone, flags);
if (slab)
return (slab);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(last);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
/*
* Loop until we have a slab incase of transient failures
* while M_WAITOK is specified. I'm not sure this is 100%
* required but we've done it for so long now.
*/
for (;;) {
empty = 0;
full = 0;
/*
* Search the available kegs for slabs. Be careful to hold the
* correct lock while calling into the keg layer.
*/
LIST_FOREACH(klink, &zone->uz_kegs, kl_link) {
keg = klink->kl_keg;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if ((keg->uk_flags & UMA_ZFLAG_FULL) == 0) {
slab = keg_fetch_slab(keg, zone, flags);
if (slab)
return (slab);
}
if (keg->uk_flags & UMA_ZFLAG_FULL)
full++;
else
empty++;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
if (rflags & (M_NOWAIT | M_NOVM))
break;
flags = rflags;
/*
* All kegs are full. XXX We can't atomically check all kegs
* and sleep so just sleep for a short period and retry.
*/
if (full && !empty) {
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
ZONE_LOCK(zone);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_flags |= UMA_ZFLAG_FULL;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
zone->uz_sleeps++;
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
zone_log_warning(zone);
Add a safety net to reclaim mbufs when one of the mbuf zones become exhausted. It is possible for a bug in the code (or, theoretically, even unusual network conditions) to exhaust all possible mbufs or mbuf clusters. When this occurs, things can grind to a halt fairly quickly. However, we currently do not call mb_reclaim() unless the entire system is experiencing a low-memory condition. While it is best to try to prevent exhaustion of one of the mbuf zones, it would also be useful to have a mechanism to attempt to recover from these situations by freeing "expendable" mbufs. This patch makes two changes: a) The patch adds a generic API to the UMA zone allocator to set a function that should be called when an allocation fails because the zone limit has been reached. Because of the way this function can be called, it really should do minimal work. b) The patch uses this API to try to free mbufs when an allocation fails from one of the mbuf zones because the zone limit has been reached. The function schedules a callout to run mb_reclaim(). Differential Revision: https://reviews.freebsd.org/D3864 Reviewed by: gnn Comments by: rrs, glebius MFC after: 2 weeks Sponsored by: Juniper Networks
2015-12-20 02:05:33 +00:00
zone_maxaction(zone);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
msleep(zone, zone->uz_lockptr, PVM,
"zonelimit", hz/100);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_flags &= ~UMA_ZFLAG_FULL;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
ZONE_UNLOCK(zone);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
continue;
}
}
return (NULL);
}
Plug a race and a leak in UMA. 1) The race has to do with zone destruction. From the zone destructor we would lock the zone, set the working set size to 0, then unlock the zone, drain it, and then free the structure. Within the window following the working-set-size set to 0 and unlocking of the zone and the point where in zone_drain we re-acquire the zone lock, the uma timer routine could have fired off and changed the working set size to something non-zero, thereby potentially preventing us from completely freeing slabs before destroying the zone (and thus leaking them). 2) The leak has to do with zone destruction as well. When destroying a zone we would take care to free all the buckets cached in the zone, but although we would drain the pcpu cache buckets, we would not free them. This resulted in leaking a couple of bucket structures (512 bytes each) per cpu on SMP during zone destruction. While I'm here, also silence GCC warnings by turning uma_slab_alloc() from inline to real function. It's too big to be an inline. Reviewed by: JeffR
2003-07-30 18:55:15 +00:00
static void *
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
{
void *item;
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint8_t freei;
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
MPASS(keg == slab->us_keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
mtx_assert(&keg->uk_lock, MA_OWNED);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
freei = BIT_FFS(SLAB_SETSIZE, &slab->us_free) - 1;
BIT_CLR(SLAB_SETSIZE, freei, &slab->us_free);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
item = slab->us_data + (keg->uk_rsize * freei);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
slab->us_freecount--;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_free--;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
/* Move this slab to the full list */
if (slab->us_freecount == 0) {
LIST_REMOVE(slab, us_link);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_full_slab, slab, us_link);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
return (item);
}
static int
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_import(uma_zone_t zone, void **bucket, int max, int flags)
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
{
uma_slab_t slab;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t keg;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
int i;
- Introduce the new M_NOVM option which tells uma to only check the currently allocated slabs and bucket caches for free items. It will not go ask the vm for pages. This differs from M_NOWAIT in that it not only doesn't block, it doesn't even ask. - Add a new zcreate option ZONE_VM, that sets the BUCKETCACHE zflag. This tells uma that it should only allocate buckets out of the bucket cache, and not from the VM. It does this by using the M_NOVM option to zalloc when getting a new bucket. This is so that the VM doesn't recursively enter itself while trying to allocate buckets for vm_map_entry zones. If there are already allocated buckets when we get here we'll still use them but otherwise we'll skip it. - Use the ZONE_VM flag on vm map entries and pv entries on x86.
2002-06-17 22:02:41 +00:00
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
slab = NULL;
keg = NULL;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
/* Try to keep the buckets totally full */
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
for (i = 0; i < max; ) {
if ((slab = zone->uz_slab(zone, keg, flags)) == NULL)
break;
keg = slab->us_keg;
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
while (slab->us_freecount && i < max) {
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
bucket[i++] = slab_alloc_item(keg, slab);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
if (keg->uk_free <= keg->uk_reserve)
break;
}
/* Don't grab more than one slab at a time. */
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
flags &= ~M_WAITOK;
flags |= M_NOWAIT;
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (slab != NULL)
KEG_UNLOCK(keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
return i;
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
static uma_bucket_t
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
zone_alloc_bucket(uma_zone_t zone, void *udata, int flags)
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
{
uma_bucket_t bucket;
int max;
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
/* Don't wait for buckets, preserve caller's NOVM setting. */
bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (bucket == NULL)
Don't count bucket allocation failures for UMA zones as their own failures. There are good reasons for this to happen, such as recursion prevention, etc. and they are not fatal since buckets are just an optimization mechanism. Real bucket allocation failures are any way counted by the bucket zones themselves, and we don't need double accounting there.
2013-11-27 20:16:18 +00:00
return (NULL);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
max = MIN(bucket->ub_entries, zone->uz_count);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
max, flags);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/*
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
* Initialize the memory if necessary.
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
*/
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
int i;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
for (i = 0; i < bucket->ub_cnt; i++)
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (zone->uz_init(bucket->ub_bucket[i], zone->uz_size,
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
flags) != 0)
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
break;
/*
* If we couldn't initialize the whole bucket, put the
* rest back onto the freelist.
*/
if (i != bucket->ub_cnt) {
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
bucket->ub_cnt - i);
Fix a INVARIANTS-only bug introduced in Revision 1.104: IF INVARIANTS is defined, and in the rare case that we have allocated some objects from the slab and at least one initializer on at least one of those objects failed, and we need to fail the allocation and push the uninitialized items back into the slab caches -- in that scenario, we would fail to [re]set the bucket cache's ub_bucket item references to NULL, which would eventually trigger a KASSERT.
2004-10-27 21:19:35 +00:00
#ifdef INVARIANTS
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
bzero(&bucket->ub_bucket[i],
sizeof(void *) * (bucket->ub_cnt - i));
Fix a INVARIANTS-only bug introduced in Revision 1.104: IF INVARIANTS is defined, and in the rare case that we have allocated some objects from the slab and at least one initializer on at least one of those objects failed, and we need to fail the allocation and push the uninitialized items back into the slab caches -- in that scenario, we would fail to [re]set the bucket cache's ub_bucket item references to NULL, which would eventually trigger a KASSERT.
2004-10-27 21:19:35 +00:00
#endif
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
bucket->ub_cnt = i;
}
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Don't count bucket allocation failures for UMA zones as their own failures. There are good reasons for this to happen, such as recursion prevention, etc. and they are not fatal since buckets are just an optimization mechanism. Real bucket allocation failures are any way counted by the bucket zones themselves, and we don't need double accounting there.
2013-11-27 20:16:18 +00:00
if (bucket->ub_cnt == 0) {
bucket_free(zone, bucket, udata);
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
atomic_add_long(&zone->uz_fails, 1);
return (NULL);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
return (bucket);
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
* Allocates a single item from a zone.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Arguments
* zone The zone to alloc for.
* udata The data to be passed to the constructor.
Back out M_* changes, per decision of the TRB. Approved by: trb
2003-02-19 05:47:46 +00:00
* flags M_WAITOK, M_NOWAIT, M_ZERO.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*
* Returns
* NULL if there is no memory and M_NOWAIT is set
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
* An item if successful
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
static void *
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone_alloc_item(uma_zone_t zone, void *udata, int flags)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
void *item;
item = NULL;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (zone->uz_import(zone->uz_arg, &item, 1, flags) != 1)
goto fail;
atomic_add_long(&zone->uz_allocs, 1);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/*
* We have to call both the zone's init (not the keg's init)
* and the zone's ctor. This is because the item is going from
* a keg slab directly to the user, and the user is expecting it
* to be both zone-init'd as well as zone-ctor'd.
*/
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
if (zone->uz_init != NULL) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (zone->uz_init(item, zone->uz_size, flags) != 0) {
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(zone, item, udata, SKIP_FINI);
goto fail;
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
}
}
if (zone->uz_ctor != NULL) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (zone->uz_ctor(item, zone->uz_size, udata, flags) != 0) {
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(zone, item, udata, SKIP_DTOR);
goto fail;
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
}
}
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
#ifdef INVARIANTS
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
uma_dbg_alloc(zone, NULL, item);
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
#endif
- Now that uma_zalloc_internal is not the fast path don't be so fussy about extra function calls. Refactor uma_zalloc_internal into seperate functions for finding the most appropriate slab, filling buckets, allocating single items, and pulling items off of slabs. This makes the code significantly cleaner. - This also fixes the "Returning an empty bucket." panic that a few people have seen. Tested On: alpha, x86
2002-10-24 07:59:03 +00:00
if (flags & M_ZERO)
Make M_ZERO flag work correctly on UMA_ZONE_PCPU zones. Sponsored by: Nginx, Inc.
2014-02-10 19:48:26 +00:00
uma_zero_item(item, zone);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
zone->uz_name, zone);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
return (item);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
fail:
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
zone->uz_name, zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
atomic_add_long(&zone->uz_fails, 1);
return (NULL);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/* See uma.h */
void
uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
{
uma_cache_t cache;
uma_bucket_t bucket;
Grow UMA zone bucket size also on lock congestion during item free. Lock congestion is the same, whether it happens on alloc or free, so handle it equally. Now that we have back pressure, there is no problem to grow buckets a bit faster. Any way growth is much slower then in 9.x.
2013-11-19 10:17:10 +00:00
int lockfail;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
int cpu;
Make the UMA harvesting go away completely if not wanted. Default to "not wanted". Provide and document the RANDOM_ENABLE_UMA option. Change RANDOM_FAST to RANDOM_UMA to clarify the harvesting. Remove RANDOM_DEBUG option, replace with SDT probes. These will be of use to folks measuring the harvesting effect when deciding whether to use RANDOM_ENABLE_UMA. Requested by: scottl and others. Approved by: so (/dev/random blanket) Differential Revision: https://reviews.freebsd.org/D3197
2015-08-22 12:59:05 +00:00
/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
random_harvest_fast_uma(&zone, sizeof(zone), 1, RANDOM_UMA);
This is the much-discussed major upgrade to the random(4) device, known to you all as /dev/random. This code has had an extensive rewrite and a good series of reviews, both by the author and other parties. This means a lot of code has been simplified. Pluggable structures for high-rate entropy generators are available, and it is most definitely not the case that /dev/random can be driven by only a hardware souce any more. This has been designed out of the device. Hardware sources are stirred into the CSPRNG (Yarrow, Fortuna) like any other entropy source. Pluggable modules may be written by third parties for additional sources. The harvesting structures and consequently the locking have been simplified. Entropy harvesting is done in a more general way (the documentation for this will follow). There is some GREAT entropy to be had in the UMA allocator, but it is disabled for now as messing with that is likely to annoy many people. The venerable (but effective) Yarrow algorithm, which is no longer supported by its authors now has an alternative, Fortuna. For now, Yarrow is retained as the default algorithm, but this may be changed using a kernel option. It is intended to make Fortuna the default algorithm for 11.0. Interested parties are encouraged to read ISBN 978-0-470-47424-2 "Cryptography Engineering" By Ferguson, Schneier and Kohno for Fortuna's gory details. Heck, read it anyway. Many thanks to Arthur Mesh who did early grunt work, and who got caught in the crossfire rather more than he deserved to. My thanks also to folks who helped me thresh this out on whiteboards and in the odd "Hallway track", or otherwise. My Nomex pants are on. Let the feedback commence! Reviewed by: trasz,des(partial),imp(partial?),rwatson(partial?) Approved by: so(des)
2014-10-30 21:21:53 +00:00
Generate KTR trace records for uma_zalloc_arg() and uma_zfree_arg(). This doesn't trace every event of interest in UMA, but provides enough basic information to explain lock traces and sleep patterns.
2004-08-06 21:52:38 +00:00
CTR2(KTR_UMA, "uma_zfree_arg thread %x zone %s", curthread,
zone->uz_name);
Don't make assertions about td_critnest when the scheduler is stopped. A panicking thread always executes with a critical section held, so any attempt to allocate or free memory while dumping will otherwise cause a second panic. This can occur, for example, if xpt_polled_action() completes non-dump I/O that was pending at the time of the panic. The fact that this can occur is itself a bug, but asserting in this case does little but reduce the reliability of kernel dumps. Suggested by: kib Reported by: pho
2015-12-11 20:05:07 +00:00
KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
Consistently enforce the restriction against calling malloc/free when in a critical section. uma_zalloc_arg()/uma_zalloc_free() may acquire a sleepable lock on the zone. The malloc() family of functions may call uma_zalloc_arg() or uma_zalloc_free(). The malloc(9) man page currently claims that free() will never sleep. It also implies that the malloc() family of functions will not sleep when called with M_NOWAIT. However, it is more correct to say that these functions will not sleep indefinitely. Indeed, they may acquire a sleepable lock. However, a developer may overlook this restriction because the WITNESS check that catches attempts to call the malloc() family of functions within a critical section is inconsistenly applied. This change clarifies the language of the malloc(9) man page to clarify the restriction against calling the malloc() family of functions while in a critical section or holding a spin lock. It also adds KASSERTs at appropriate points to make the enforcement of this restriction more consistent. PR: 204633 Differential Revision: https://reviews.freebsd.org/D4197 Reviewed by: markj Approved by: gnn (mentor) Sponsored by: Juniper Networks
2015-11-19 14:04:53 +00:00
("uma_zfree_arg: called with spinlock or critical section held"));
uma_zfree(zone, NULL) should do nothing, to match free(9). Noticed by: Ron Steinke <rsteinke at isilon dot com> MFC after: 3 days
2010-10-19 16:06:00 +00:00
/* uma_zfree(..., NULL) does nothing, to match free(9). */
if (item == NULL)
return;
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
#ifdef DEBUG_MEMGUARD
if (is_memguard_addr(item)) {
Fix memguard(9) in kernels with INVARIANTS enabled. With r284861, UMA zones use the trash ctor and dtor by default. This is incompatible with memguard, which frees the backing page when the item is freed. Modify the UMA debug functions to be no-ops if the item was allocated from memguard. This also fixes constructors such as mb_ctor_pack(), which invokes the trash ctor in addition to performing some initialization. Reviewed by: glebius MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D6562
2016-06-01 22:31:35 +00:00
if (zone->uz_dtor != NULL)
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
zone->uz_dtor(item, zone->uz_size, udata);
Fix memguard(9) in kernels with INVARIANTS enabled. With r284861, UMA zones use the trash ctor and dtor by default. This is incompatible with memguard, which frees the backing page when the item is freed. Modify the UMA debug functions to be no-ops if the item was allocated from memguard. This also fixes constructors such as mb_ctor_pack(), which invokes the trash ctor in addition to performing some initialization. Reviewed by: glebius MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D6562
2016-06-01 22:31:35 +00:00
if (zone->uz_fini != NULL)
Make memguard(9) capable to guard uma(9) allocations.
2011-10-12 18:08:28 +00:00
zone->uz_fini(item, zone->uz_size);
memguard_free(item);
return;
}
#endif
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
#ifdef INVARIANTS
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (zone->uz_flags & UMA_ZONE_MALLOC)
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
uma_dbg_free(zone, udata, item);
else
uma_dbg_free(zone, NULL, item);
#endif
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (zone->uz_dtor != NULL)
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
zone->uz_dtor(item, zone->uz_size, udata);
Fix the calculation that determines uz_maxpages. It was off for large zones. Fortunately we have no large zones with maximums specified yet, so it wasn't breaking anything. Implement blocking when a zone exceeds the maximum and M_WAITOK is specified. Previously this just failed like the old zone allocator did. The old zone allocator didn't support WAITOK/NOWAIT though so we should do what we advertise. While I was in there I cleaned up some more zalloc logic to further simplify that code path and reduce redundant code. This was needed to make the blocking work properly anyway.
2002-04-14 01:56:25 +00:00
/*
* The race here is acceptable. If we miss it we'll just have to wait
* a little longer for the limits to be reset.
*/
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (zone->uz_flags & UMA_ZFLAG_FULL)
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
goto zfree_item;
Fix the calculation that determines uz_maxpages. It was off for large zones. Fortunately we have no large zones with maximums specified yet, so it wasn't breaking anything. Implement blocking when a zone exceeds the maximum and M_WAITOK is specified. Previously this just failed like the old zone allocator did. The old zone allocator didn't support WAITOK/NOWAIT though so we should do what we advertise. While I was in there I cleaned up some more zalloc logic to further simplify that code path and reduce redundant code. This was needed to make the blocking work properly anyway.
2002-04-14 01:56:25 +00:00
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
/*
* If possible, free to the per-CPU cache. There are two
* requirements for safe access to the per-CPU cache: (1) the thread
* accessing the cache must not be preempted or yield during access,
* and (2) the thread must not migrate CPUs without switching which
* cache it accesses. We rely on a critical section to prevent
* preemption and migration. We release the critical section in
* order to acquire the zone mutex if we are unable to free to the
* current cache; when we re-acquire the critical section, we must
* detect and handle migration if it has occurred.
*/
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
zfree_restart:
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
critical_enter();
cpu = curcpu;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
cache = &zone->uz_cpu[cpu];
zfree_start:
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* Try to free into the allocbucket first to give LIFO ordering
* for cache-hot datastructures. Spill over into the freebucket
* if necessary. Alloc will swap them if one runs dry.
*/
bucket = cache->uc_allocbucket;
if (bucket == NULL || bucket->ub_cnt >= bucket->ub_entries)
bucket = cache->uc_freebucket;
if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
KASSERT(bucket->ub_bucket[bucket->ub_cnt] == NULL,
("uma_zfree: Freeing to non free bucket index."));
bucket->ub_bucket[bucket->ub_cnt] = item;
bucket->ub_cnt++;
cache->uc_frees++;
critical_exit();
return;
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
* We must go back the zone, which requires acquiring the zone lock,
* which in turn means we must release and re-acquire the critical
* section. Since the critical section is released, we may be
* preempted or migrate. As such, make sure not to maintain any
* thread-local state specific to the cache from prior to releasing
* the critical section.
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
*/
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
critical_exit();
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (zone->uz_count == 0 || bucketdisable)
goto zfree_item;
Grow UMA zone bucket size also on lock congestion during item free. Lock congestion is the same, whether it happens on alloc or free, so handle it equally. Now that we have back pressure, there is no problem to grow buckets a bit faster. Any way growth is much slower then in 9.x.
2013-11-19 10:17:10 +00:00
lockfail = 0;
if (ZONE_TRYLOCK(zone) == 0) {
/* Record contention to size the buckets. */
ZONE_LOCK(zone);
lockfail = 1;
}
Modify UMA to use critical sections to protect per-CPU caches, rather than mutexes, which offers lower overhead on both UP and SMP. When allocating from or freeing to the per-cpu cache, without INVARIANTS enabled, we now no longer perform any mutex operations, which offers a 1%-3% performance improvement in a variety of micro-benchmarks. We rely on critical sections to prevent (a) preemption resulting in reentrant access to UMA on a single CPU, and (b) migration of the thread during access. In the event we need to go back to the zone for a new bucket, we release the critical section to acquire the global zone mutex, and must re-acquire the critical section and re-evaluate which cache we are accessing in case migration has occured, or circumstances have changed in the current cache. Per-CPU cache statistics are now gathered lock-free by the sysctl, which can result in small races in statistics reporting for caches. Reviewed by: bmilekic, jeff (somewhat) Tested by: rwatson, kris, gnn, scottl, mike at sentex dot net, others
2005-04-29 18:56:36 +00:00
critical_enter();
cpu = curcpu;
cache = &zone->uz_cpu[cpu];
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
/*
* Since we have locked the zone we may as well send back our stats.
*/
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
atomic_add_long(&zone->uz_frees, cache->uc_frees);
Further UMA statistics related changes: - Add a new uma_zfree_internal() flag, ZFREE_STATFREE, which causes it to to update the zone's uz_frees statistic. Previously, the statistic was updated unconditionally. - Use the flag in situations where a "real" free occurs: i.e., one where the caller is freeing an allocated item, to be differentiated from situations where uma_zfree_internal() is used to tear down the item during slab teardown in order to invoke its fini() method. Also use the flag when UMA is freeing its internal objects. - When exchanging a bucket with the zone from the per-CPU cache when freeing an item, flush cache statistics back to the zone (since the zone lock and critical section are both held) to match the allocation case. MFC after: 3 days
2005-07-20 18:47:42 +00:00
cache->uc_allocs = 0;
cache->uc_frees = 0;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
bucket = cache->uc_freebucket;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
if (bucket != NULL && bucket->ub_cnt < bucket->ub_entries) {
ZONE_UNLOCK(zone);
goto zfree_start;
}
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
cache->uc_freebucket = NULL;
Release the second critical section in uma_zfree_arg() slightly earlier. It is only needed when removing a full bucket from the per-CPU cache. The bucket cache (uz_buckets) is protected by the zone mutex and thus the critical section can be released before inserting into that list. MFC after: 1 week
2016-07-20 01:01:50 +00:00
/* We are no longer associated with this CPU. */
critical_exit();
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
/* Can we throw this on the zone full list? */
if (bucket != NULL) {
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR3(KTR_UMA,
"uma_zfree: zone %s(%p) putting bucket %p on free list",
zone->uz_name, zone, bucket);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
/* ub_cnt is pointing to the last free item */
KASSERT(bucket->ub_cnt != 0,
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
("uma_zfree: Attempting to insert an empty bucket onto the full list.\n"));
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
LIST_INSERT_HEAD(&zone->uz_buckets, bucket, ub_link);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
}
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
Grow UMA zone bucket size also on lock congestion during item free. Lock congestion is the same, whether it happens on alloc or free, so handle it equally. Now that we have back pressure, there is no problem to grow buckets a bit faster. Any way growth is much slower then in 9.x.
2013-11-19 10:17:10 +00:00
/*
* We bump the uz count when the cache size is insufficient to
* handle the working set.
*/
if (lockfail && zone->uz_count < BUCKET_MAX)
zone->uz_count++;
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
ZONE_UNLOCK(zone);
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket = bucket_alloc(zone, udata, M_NOWAIT);
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR3(KTR_UMA, "uma_zfree: zone %s(%p) allocated bucket %p",
zone->uz_name, zone, bucket);
Honor the BUCKETCACHE flag on free as well.
2002-06-17 23:53:58 +00:00
if (bucket) {
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
critical_enter();
cpu = curcpu;
cache = &zone->uz_cpu[cpu];
if (cache->uc_freebucket == NULL) {
cache->uc_freebucket = bucket;
goto zfree_start;
}
/*
* We lost the race, start over. We have to drop our
* critical section to free the bucket.
*/
critical_exit();
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
bucket_free(zone, bucket, udata);
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
goto zfree_restart;
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Rework most of the bucket allocation and free code so that per cpu locks are never held across blocking operations. Also, fix two other lock order reversals that were exposed by jhb's witness change. The free path previously had a bug that would cause it to skip the free bucket list in some cases and go straight to allocating a new bucket. This has been fixed as well. These changes made the bucket handling code much cleaner and removed quite a few lock operations. This should be marginally faster now. It is now possible to call malloc w/o Giant and avoid any witness warnings. This still isn't entirely safe though because malloc_type statistics are not protected by any lock.
2002-04-08 02:42:55 +00:00
/*
* If nothing else caught this, we'll just do an internal free.
*/
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
zfree_item:
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(zone, item, udata, SKIP_DTOR);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
return;
}
static void
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
slab_free_item(uma_keg_t keg, uma_slab_t slab, void *item)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint8_t freei;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
mtx_assert(&keg->uk_lock, MA_OWNED);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
MPASS(keg == slab->us_keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* Do we need to remove from any lists? */
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (slab->us_freecount+1 == keg->uk_ipers) {
Revert last commit, I have no idea what happened.
2003-06-09 22:51:36 +00:00
LIST_REMOVE(slab, us_link);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
} else if (slab->us_freecount == 0) {
LIST_REMOVE(slab, us_link);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_part_slab, slab, us_link);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
/* Slab management. */
freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
BIT_SET(SLAB_SETSIZE, freei, &slab->us_free);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
slab->us_freecount++;
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
/* Keg statistics. */
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_free++;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
}
static void
zone_release(uma_zone_t zone, void **bucket, int cnt)
{
void *item;
uma_slab_t slab;
uma_keg_t keg;
uint8_t *mem;
int clearfull;
int i;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
clearfull = 0;
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
keg = zone_first_keg(zone);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
for (i = 0; i < cnt; i++) {
item = bucket[i];
if (!(zone->uz_flags & UMA_ZONE_VTOSLAB)) {
mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
if (zone->uz_flags & UMA_ZONE_HASH) {
slab = hash_sfind(&keg->uk_hash, mem);
} else {
mem += keg->uk_pgoff;
slab = (uma_slab_t)mem;
}
} else {
slab = vtoslab((vm_offset_t)item);
if (slab->us_keg != keg) {
KEG_UNLOCK(keg);
keg = slab->us_keg;
KEG_LOCK(keg);
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
slab_free_item(keg, slab, item);
if (keg->uk_flags & UMA_ZFLAG_FULL) {
if (keg->uk_pages < keg->uk_maxpages) {
keg->uk_flags &= ~UMA_ZFLAG_FULL;
clearfull = 1;
}
Fix the calculation that determines uz_maxpages. It was off for large zones. Fortunately we have no large zones with maximums specified yet, so it wasn't breaking anything. Implement blocking when a zone exceeds the maximum and M_WAITOK is specified. Previously this just failed like the old zone allocator did. The old zone allocator didn't support WAITOK/NOWAIT though so we should do what we advertise. While I was in there I cleaned up some more zalloc logic to further simplify that code path and reduce redundant code. This was needed to make the blocking work properly anyway.
2002-04-14 01:56:25 +00:00
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
/*
* We can handle one more allocation. Since we're
* clearing ZFLAG_FULL, wake up all procs blocked
* on pages. This should be uncommon, so keeping this
* simple for now (rather than adding count of blocked
* threads etc).
*/
wakeup(keg);
}
Fix the calculation that determines uz_maxpages. It was off for large zones. Fortunately we have no large zones with maximums specified yet, so it wasn't breaking anything. Implement blocking when a zone exceeds the maximum and M_WAITOK is specified. Previously this just failed like the old zone allocator did. The old zone allocator didn't support WAITOK/NOWAIT though so we should do what we advertise. While I was in there I cleaned up some more zalloc logic to further simplify that code path and reduce redundant code. This was needed to make the blocking work properly anyway.
2002-04-14 01:56:25 +00:00
}
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (clearfull) {
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
ZONE_LOCK(zone);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_flags &= ~UMA_ZFLAG_FULL;
wakeup(zone);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
ZONE_UNLOCK(zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
}
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
/*
* Frees a single item to any zone.
*
* Arguments:
* zone The zone to free to
* item The item we're freeing
* udata User supplied data for the dtor
* skip Skip dtors and finis
*/
static void
zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
{
#ifdef INVARIANTS
if (skip == SKIP_NONE) {
if (zone->uz_flags & UMA_ZONE_MALLOC)
uma_dbg_free(zone, udata, item);
else
uma_dbg_free(zone, NULL, item);
}
#endif
if (skip < SKIP_DTOR && zone->uz_dtor)
zone->uz_dtor(item, zone->uz_size, udata);
if (skip < SKIP_FINI && zone->uz_fini)
zone->uz_fini(item, zone->uz_size);
atomic_add_long(&zone->uz_frees, 1);
zone->uz_release(zone->uz_arg, &item, 1);
}
Add uma_zone_set_max() to add enforced limits to non vm obj backed zones.
2002-03-20 05:28:34 +00:00
/* See uma.h */
Change uma_zone_set_max to return the effective value of "nitems" after rounding. The same value can also be obtained with uma_zone_get_max, but this change avoids a caller having to make two back-to-back calls. Sponsored by: FreeBSD Foundation Reviewed by: gnn, jhb
2010-10-16 04:41:45 +00:00
int
Add uma_zone_set_max() to add enforced limits to non vm obj backed zones.
2002-03-20 05:28:34 +00:00
uma_zone_set_max(uma_zone_t zone, int nitems)
{
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (keg == NULL)
return (0);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_maxpages = (nitems / keg->uk_ipers) * keg->uk_ppera;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (keg->uk_maxpages * keg->uk_ipers < nitems)
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_maxpages += keg->uk_ppera;
uma: fix pages <-> items conversions at several places Those places were not taking into account uk_ppera. At present one allocation is always used by one slab, so uk_ppera must be used to convert between pages and slabs. uk_ipers is used to convert between slabs and items. MFC after: 1 month (if ever)
2017-03-11 16:43:38 +00:00
nitems = (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
Change uma_zone_set_max to return the effective value of "nitems" after rounding. The same value can also be obtained with uma_zone_get_max, but this change avoids a caller having to make two back-to-back calls. Sponsored by: FreeBSD Foundation Reviewed by: gnn, jhb
2010-10-16 04:41:45 +00:00
return (nitems);
Add uma_zone_set_max() to add enforced limits to non vm obj backed zones.
2002-03-20 05:28:34 +00:00
}
Add uma_zone_get_max() to obtain the effective limit after a call to uma_zone_set_max(). The UMA zone limit is not exactly set to the value supplied but rounded up to completely fill the backing store increment (a page normally). This can lead to surprising situations where the number of elements allocated from UMA is higher than the supplied limit value. The new get function reads back the effective value so that the supplied limit value can be adjusted to the real limit. Reviewed by: jeffr MFC after: 1 week
2010-08-16 14:24:00 +00:00
/* See uma.h */
int
uma_zone_get_max(uma_zone_t zone)
{
int nitems;
uma_keg_t keg;
keg = zone_first_keg(zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (keg == NULL)
return (0);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
uma: fix pages <-> items conversions at several places Those places were not taking into account uk_ppera. At present one allocation is always used by one slab, so uk_ppera must be used to convert between pages and slabs. uk_ipers is used to convert between slabs and items. MFC after: 1 month (if ever)
2017-03-11 16:43:38 +00:00
nitems = (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
Add uma_zone_get_max() to obtain the effective limit after a call to uma_zone_set_max(). The UMA zone limit is not exactly set to the value supplied but rounded up to completely fill the backing store increment (a page normally). This can lead to surprising situations where the number of elements allocated from UMA is higher than the supplied limit value. The new get function reads back the effective value so that the supplied limit value can be adjusted to the real limit. Reviewed by: jeffr MFC after: 1 week
2010-08-16 14:24:00 +00:00
return (nitems);
}
Implemented uma_zone_set_warning(9) function that sets a warning, which will be printed once the given zone becomes full and cannot allocate an item. The warning will not be printed more often than every five minutes. All UMA warnings can be globally turned off by setting sysctl/tunable vm.zone_warnings to 0. Discussed on: arch Obtained from: WHEEL Systems MFC after: 2 weeks
2012-12-07 22:27:13 +00:00
/* See uma.h */
void
uma_zone_set_warning(uma_zone_t zone, const char *warning)
{
ZONE_LOCK(zone);
zone->uz_warning = warning;
ZONE_UNLOCK(zone);
}
Add a safety net to reclaim mbufs when one of the mbuf zones become exhausted. It is possible for a bug in the code (or, theoretically, even unusual network conditions) to exhaust all possible mbufs or mbuf clusters. When this occurs, things can grind to a halt fairly quickly. However, we currently do not call mb_reclaim() unless the entire system is experiencing a low-memory condition. While it is best to try to prevent exhaustion of one of the mbuf zones, it would also be useful to have a mechanism to attempt to recover from these situations by freeing "expendable" mbufs. This patch makes two changes: a) The patch adds a generic API to the UMA zone allocator to set a function that should be called when an allocation fails because the zone limit has been reached. Because of the way this function can be called, it really should do minimal work. b) The patch uses this API to try to free mbufs when an allocation fails from one of the mbuf zones because the zone limit has been reached. The function schedules a callout to run mb_reclaim(). Differential Revision: https://reviews.freebsd.org/D3864 Reviewed by: gnn Comments by: rrs, glebius MFC after: 2 weeks Sponsored by: Juniper Networks
2015-12-20 02:05:33 +00:00
/* See uma.h */
void
uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
{
ZONE_LOCK(zone);
Redo r292484. Embed task(9) into zone, so that uz_maxaction is called in a context that can sleep, allowing consumers of the KPI to run their drain routines without any extra measures. Discussed with: jtl
2016-02-03 23:30:17 +00:00
TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
Add a safety net to reclaim mbufs when one of the mbuf zones become exhausted. It is possible for a bug in the code (or, theoretically, even unusual network conditions) to exhaust all possible mbufs or mbuf clusters. When this occurs, things can grind to a halt fairly quickly. However, we currently do not call mb_reclaim() unless the entire system is experiencing a low-memory condition. While it is best to try to prevent exhaustion of one of the mbuf zones, it would also be useful to have a mechanism to attempt to recover from these situations by freeing "expendable" mbufs. This patch makes two changes: a) The patch adds a generic API to the UMA zone allocator to set a function that should be called when an allocation fails because the zone limit has been reached. Because of the way this function can be called, it really should do minimal work. b) The patch uses this API to try to free mbufs when an allocation fails from one of the mbuf zones because the zone limit has been reached. The function schedules a callout to run mb_reclaim(). Differential Revision: https://reviews.freebsd.org/D3864 Reviewed by: gnn Comments by: rrs, glebius MFC after: 2 weeks Sponsored by: Juniper Networks
2015-12-20 02:05:33 +00:00
ZONE_UNLOCK(zone);
}
- Simplify implementation of uma_zone_get_max. - Add uma_zone_get_cur which returns the current approximate occupancy of a zone. This is useful for providing stats via sysctl amongst other things. Sponsored by: FreeBSD Foundation Reviewed by: gnn, jhb MFC after: 2 weeks
2010-10-16 04:14:45 +00:00
/* See uma.h */
int
uma_zone_get_cur(uma_zone_t zone)
{
int64_t nitems;
u_int i;
ZONE_LOCK(zone);
nitems = zone->uz_allocs - zone->uz_frees;
CPU_FOREACH(i) {
/*
* See the comment in sysctl_vm_zone_stats() regarding the
* safety of accessing the per-cpu caches. With the zone lock
* held, it is safe, but can potentially result in stale data.
*/
nitems += zone->uz_cpu[i].uc_allocs -
zone->uz_cpu[i].uc_frees;
}
ZONE_UNLOCK(zone);
return (nitems < 0 ? 0 : nitems);
}
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
/* See uma.h */
void
uma_zone_set_init(uma_zone_t zone, uma_init uminit)
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t keg;
keg = zone_first_keg(zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
KASSERT(keg != NULL, ("uma_zone_set_init: Invalid zone type"));
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KASSERT(keg->uk_pages == 0,
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
("uma_zone_set_init on non-empty keg"));
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_init = uminit;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
/* See uma.h */
void
uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t keg;
keg = zone_first_keg(zone);
Fix wrong kassert msg in uma. PR: 199172 Submitted by: luke.tw gmail com MFC after: 1 week
2015-04-05 18:25:23 +00:00
KASSERT(keg != NULL, ("uma_zone_set_fini: Invalid zone type"));
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KASSERT(keg->uk_pages == 0,
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
("uma_zone_set_fini on non-empty keg"));
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_fini = fini;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
}
/* See uma.h */
void
uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
{
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
ZONE_LOCK(zone);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KASSERT(zone_first_keg(zone)->uk_pages == 0,
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
("uma_zone_set_zinit on non-empty keg"));
zone->uz_init = zinit;
ZONE_UNLOCK(zone);
}
/* See uma.h */
void
uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
{
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
ZONE_LOCK(zone);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
KASSERT(zone_first_keg(zone)->uk_pages == 0,
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
("uma_zone_set_zfini on non-empty keg"));
zone->uz_fini = zfini;
ZONE_UNLOCK(zone);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* See uma.h */
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
/* XXX uk_freef is not actually used with the zone locked */
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
void
uma_zone_set_freef(uma_zone_t zone, uma_free freef)
{
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
uma_keg_t keg;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
keg = zone_first_keg(zone);
Fix wrong kassert msg in uma. PR: 199172 Submitted by: luke.tw gmail com MFC after: 1 week
2015-04-05 18:25:23 +00:00
KASSERT(keg != NULL, ("uma_zone_set_freef: Invalid zone type"));
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
keg->uk_freef = freef;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/* See uma.h */
* Add a "how" argument to uma_zone constructors and initialization functions so that they know whether the allocation is supposed to be able to sleep or not. * Allow uma_zone constructors and initialation functions to return either success or error. Almost all of the ones in the tree currently return success unconditionally, but mbuf is a notable exception: the packet zone constructor wants to be able to fail if it cannot suballocate an mbuf cluster, and the mbuf allocators want to be able to fail in general in a MAC kernel if the MAC mbuf initializer fails. This fixes the panics people are seeing when they run out of memory for mbuf clusters. * Allow debug.nosleepwithlocks on WITNESS to be disabled, without changing the default. Both bmilekic and jeff have reviewed the changes made to make failable zone allocations work.
2004-08-02 00:18:36 +00:00
/* XXX uk_allocf is not actually used with the zone locked */
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
void
uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t keg;
keg = zone_first_keg(zone);
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg->uk_allocf = allocf;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
/* See uma.h */
void
uma_zone_reserve(uma_zone_t zone, int items)
{
uma_keg_t keg;
keg = zone_first_keg(zone);
if (keg == NULL)
return;
KEG_LOCK(keg);
keg->uk_reserve = items;
KEG_UNLOCK(keg);
return;
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/* See uma.h */
int
MFC
2013-02-26 23:52:23 +00:00
uma_zone_reserve_kva(uma_zone_t zone, int count)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
vm_offset_t kva;
Avoid sign extension of value passed to kva_alloc from uma_zone_reserve_kva Fixes "panic: vm_radix_reserve_kva: unable to reserve KVA" caused by sign extention of "pages * UMA_SLAB_SIZE" value passed to kva_alloc() which takes unsigned long argument. In the erroneus case that triggered this bug, the number of pages to allocate in uma_zone_reserve_kva() was 0x8ebe6, that gave the total number of bytes to allocate equal to 0x8ebe6000 (int). This was then sign extended in kva_alloc() to 0xffffffff8ebe6000 (unsigned long). Reviewed by: alc, kib Submitted by: Zbigniew Bodek <zbb@semihalf.com> Obtained from: Semihalf Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D3346
2015-08-10 17:16:49 +00:00
u_int pages;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (keg == NULL)
return (0);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
pages = count / keg->uk_ipers;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
if (pages * keg->uk_ipers < count)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
pages++;
uma: fix pages <-> items conversions at several places Those places were not taking into account uk_ppera. At present one allocation is always used by one slab, so uk_ppera must be used to convert between pages and slabs. uk_ipers is used to convert between slabs and items. MFC after: 1 month (if ever)
2017-03-11 16:43:38 +00:00
pages *= keg->uk_ppera;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
MFC
2013-02-26 23:52:23 +00:00
#ifdef UMA_MD_SMALL_ALLOC
if (keg->uk_ppera > 1) {
#else
if (1) {
#endif
uma: fix pages <-> items conversions at several places Those places were not taking into account uk_ppera. At present one allocation is always used by one slab, so uk_ppera must be used to convert between pages and slabs. uk_ipers is used to convert between slabs and items. MFC after: 1 month (if ever)
2017-03-11 16:43:38 +00:00
kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
MFC
2013-02-26 23:52:23 +00:00
if (kva == 0)
return (0);
} else
kva = 0;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_kva = kva;
MFC
2013-02-26 23:52:23 +00:00
keg->uk_offset = 0;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_maxpages = pages;
MFC
2013-02-26 23:52:23 +00:00
#ifdef UMA_MD_SMALL_ALLOC
keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
#else
keg->uk_allocf = noobj_alloc;
#endif
- Resolve bucket recursion issues by passing a cookie with zone flags through bucket_alloc() to uma_zalloc_arg() and uma_zfree_arg(). - Make some smaller buckets for large zones to further reduce memory waste. - Implement uma_zone_reserve(). This holds aside a number of items only for callers who specify M_USE_RESERVE. buckets will never be filled from reserve allocations. Sponsored by: EMC / Isilon Storage Division
2013-06-26 00:57:38 +00:00
keg->uk_flags |= UMA_ZONE_NOFREE;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
return (1);
}
/* See uma.h */
void
uma_prealloc(uma_zone_t zone, int items)
{
int slabs;
uma_slab_t slab;
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
uma_keg_t keg;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
keg = zone_first_keg(zone);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
if (keg == NULL)
return;
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_LOCK(keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
slabs = items / keg->uk_ipers;
if (slabs * keg->uk_ipers < items)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
slabs++;
while (slabs > 0) {
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
slab = keg_alloc_slab(keg, zone, M_WAITOK);
if (slab == NULL)
break;
MPASS(slab->us_keg == keg);
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_INSERT_HEAD(&keg->uk_free_slab, slab, us_link);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
slabs--;
}
- Add a per-zone lock for zones without kegs. - Be more explicit about zone vs keg locking. This functionally changes almost nothing. - Add a size parameter to uma_zcache_create() so we can size the buckets. - Pass the zone to bucket_alloc() so it can modify allocation flags as appropriate. - Fix a bug in zone_alloc_bucket() where I missed an address of operator in a failure case. (Found by pho) Sponsored by: EMC / Isilon Storage Division
2013-06-20 19:08:12 +00:00
KEG_UNLOCK(keg);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
/* See uma.h */
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
static void
uma_reclaim_locked(bool kmem_danger)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
As old prophecy says, some day UMA_DEBUG printfs shall be made CTRs.
2017-06-01 18:36:52 +00:00
CTR0(KTR_UMA, "UMA: vm asked us to release pages!");
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
sx_assert(&uma_drain_lock, SA_XLOCKED);
Add a mechanism to disable buckets when the v_free_count drops below v_free_min. This should help performance in memory starved situations.
2002-04-08 06:20:34 +00:00
bucket_enable();
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
zone_foreach(zone_drain);
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
if (vm_page_count_min() || kmem_danger) {
Implement mechanism to safely but slowly purge UMA per-CPU caches. This is a last resort for very low memory condition in case other measures to free memory were ineffective. Sequentially cycle through all CPUs and extract per-CPU cache buckets into zone cache from where they can be freed.
2013-11-19 10:51:46 +00:00
cache_drain_safe(NULL);
zone_foreach(zone_drain);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
/*
* Some slabs may have been freed but this zone will be visited early
* we visit again so that we can free pages that are empty once other
* zones are drained. We have to do the same for buckets.
*/
- Remove the working-set algorithm. Instead, use the per cpu buckets as the working set cache. This has several advantages. Firstly, we never touch the per cpu queues now in the timeout handler. This removes one more reason for having per cpu locks. Secondly, it reduces the size of the zone by 8 bytes, bringing it under 200 bytes for a single proc x86 box. This tidies up other logic as well. - The 'destroy' flag no longer needs to be passed to zone_drain() since it always frees everything in the zone's slabs. - cache_drain() is now only called from zone_dtor() and so it destroys by default. It also does not need the destroy parameter now.
2003-09-19 23:27:46 +00:00
zone_drain(slabzone);
- Initialize a pool of bucket zones so that we waste less space on zones that don't cache as many items. - Introduce the bucket_alloc(), bucket_free() functions to wrap bucket allocation. These functions select the appropriate bucket zone to allocate from or free to. - Rename ub_ptr to ub_cnt to reflect a change in its use. ub_cnt now reflects the count of free items in the bucket. This gets rid of many unnatural subtractions by 1 throughout the code. - Add ub_entries which reflects the number of entries possibly held in a bucket.
2003-09-19 06:26:45 +00:00
bucket_zone_drain();
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
}
void
uma_reclaim(void)
{
sx_xlock(&uma_drain_lock);
uma_reclaim_locked(false);
Provide mutual exclusion between zone allocation/destruction and uma_reclaim(). Reclamation code must not see half-constructed or destructed zones. Do this by bracing uma_zcreate() and uma_zdestroy() into a shared-locked sx, and take the sx exclusively in uma_reclaim(). Usually zones are not created/destroyed during the system operation, but tmpfs mounts do cause zone operations and exposed the bug. Another solution could be to only expose a new keg on uma_kegs list after the corresponding zone is fully constructed, and similar treatment for the destruction. But it probably requires more risky code rearrangement as well. Reported and tested by: pho Discussed with: avg Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2014-11-30 20:20:55 +00:00
sx_xunlock(&uma_drain_lock);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
static int uma_reclaim_needed;
void
uma_reclaim_wakeup(void)
{
uma_reclaim_needed = 1;
wakeup(&uma_reclaim_needed);
}
void
uma_reclaim_worker(void *arg __unused)
{
sx_xlock(&uma_drain_lock);
for (;;) {
sx_sleep(&uma_reclaim_needed, &uma_drain_lock, PVM,
"umarcl", 0);
if (uma_reclaim_needed) {
uma_reclaim_needed = 0;
call vm_lowmem hook in uma_reclaim_worker A comment near kmem_reclaim() implies that we already did that. Calling the hook is useful, because some handlers, e.g. ARC, might be able to release significant amounts of KVA. Now that we have more than one place where vm_lowmem hook is called, use this change as an opportunity to introduce flags that describe a reason for calling the hook. No handler makes use of the flags yet. Reviewed by: markj, kib MFC after: 1 week Sponsored by: Panzura Differential Revision: https://reviews.freebsd.org/D9764
2017-02-25 16:39:21 +00:00
sx_xunlock(&uma_drain_lock);
EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
sx_xlock(&uma_drain_lock);
The vmem callback to reclaim kmem arena address space on low or fragmented conditions currently just wakes up the pagedaemon. The kmem arena is significantly smaller then the total available physical memory, which means that there are loads where kmem arena space could be exhausted, while there is a lot of pages available still. The woken up pagedaemon sees vm_pages_needed != 0, verifies the condition vm_paging_needed() which is false, clears the pass and returns back to sleep, not calling neither uma_reclaim() nor lowmem handler. To handle low kmem arena conditions, create additional pagedaemon thread which calls uma_reclaim() directly. The thread sleeps on the dedicated channel and kmem_reclaim() wakes the thread in addition to the pagedaemon. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
2015-05-09 20:08:36 +00:00
uma_reclaim_locked(true);
}
}
}
- Add a new function uma_zone_exhausted() to see if a zone is full. - Add a printf in swp_pager_meta_build() to warn if the swapzone becomes exhausted so that there's at least a warning before a box that runs out of swapzone space before running out of swap space deadlocks. MFC after: 1 week Reviwed by: alc
2007-01-05 19:09:01 +00:00
/* See uma.h */
int
uma_zone_exhausted(uma_zone_t zone)
{
int full;
ZONE_LOCK(zone);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
full = (zone->uz_flags & UMA_ZFLAG_FULL);
- Add a new function uma_zone_exhausted() to see if a zone is full. - Add a printf in swp_pager_meta_build() to warn if the swapzone becomes exhausted so that there's at least a warning before a box that runs out of swapzone space before running out of swap space deadlocks. MFC after: 1 week Reviwed by: alc
2007-01-05 19:09:01 +00:00
ZONE_UNLOCK(zone);
return (full);
}
Fix for problems that occur when all mbuf clusters migrate to the mbuf packet zone. Cluster allocations fail when this happens. Also processes that may have blocked on cluster allocations will never be woken up. Thanks to rwatson for an overview of the issue and pointers to the mbuma paper and his tool to dump out UMA zones. Reviewed by: andre@
2007-01-25 01:05:23 +00:00
int
uma_zone_exhausted_nolock(uma_zone_t zone)
{
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
return (zone->uz_flags & UMA_ZFLAG_FULL);
Fix for problems that occur when all mbuf clusters migrate to the mbuf packet zone. Cluster allocations fail when this happens. Also processes that may have blocked on cluster allocations will never be woken up. Thanks to rwatson for an overview of the issue and pointers to the mbuma paper and his tool to dump out UMA zones. Reviewed by: andre@
2007-01-25 01:05:23 +00:00
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
void *
Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM. Note to self: When this is MFCed, sparc64 needs the same fix. Differential revision: https://reviews.freebsd.org/D2106 Reviewed by: kib Reported by: Michael Fuckner <michael@fuckner.net> Tested by: Michael Fuckner <michael@fuckner.net> MFC after: 2 weeks
2015-04-01 12:42:26 +00:00
uma_large_malloc(vm_size_t size, int wait)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
void *mem;
uma_slab_t slab;
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint8_t flags;
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
slab = zone_alloc_item(slabzone, NULL, wait);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
if (slab == NULL)
return (NULL);
Gulp ... call kmem_malloc() without Giant.
2003-07-26 03:55:32 +00:00
mem = page_alloc(NULL, size, &flags, wait);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
if (mem) {
- Split UMA_ZFLAG_OFFPAGE into UMA_ZFLAG_OFFPAGE and UMA_ZFLAG_HASH. - Remove all instances of the mallochash. - Stash the slab pointer in the vm page's object pointer when allocating from the kmem_obj. - Use the overloaded object pointer to find slabs for malloced memory.
2002-09-18 08:26:30 +00:00
vsetslab((vm_offset_t)mem, slab);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
slab->us_data = mem;
slab->us_flags = flags | UMA_SLAB_MALLOC;
slab->us_size = size;
} else {
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(slabzone, slab, NULL, SKIP_NONE);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
return (mem);
}
void
uma_large_free(uma_slab_t slab)
{
Different consumers of the struct vm_page abuse pageq member to keep additional information, when the page is guaranteed to not belong to a paging queue. Usually, this results in a lot of type casts which make reasoning about the code correctness harder. Sometimes m->object is used instead of pageq, which could cause real and confusing bugs if non-NULL m->object is leaked. See r141955 and r253140 for examples. Change the pageq member into a union containing explicitly-typed members. Use them instead of type-punning or abusing m->object in x86 pmaps, uma and vm_page_alloc_contig(). Requested and reviewed by: alc Sponsored by: The FreeBSD Foundation
2013-08-10 17:36:42 +00:00
- Make the acquisition of Giant in vm_fault_unwire() conditional on the pmap. For the kernel pmap, Giant is not required. In general, for other pmaps, Giant is required by i386's pmap_pte() implementation. Specifically, the use of PMAP2/PADDR2 is synchronized by Giant. Note: In principle, updates to the kernel pmap's wired count could be lost without Giant. However, in practice, we never use the kernel pmap's wired count. This will be resolved when pmap locking appears. - With the above change, cpu_thread_clean() and uma_large_free() need not acquire Giant. (The first case is simply the revival of i386/i386/vm_machdep.c's revision 1.226 by peter.)
2004-03-10 04:44:43 +00:00
page_free(slab->us_data, slab->us_size, slab->us_flags);
- Add a new UMA API: uma_zcache_create(). This makes a zone without any backing memory that is only a container for per-cpu caches of arbitrary pointer items. These zones have no kegs. - Convert the regular keg based allocator to use the new import/release functions. - Move some stats to be atomics since they would require excessive zone locking/unlocking with the new import/release paradigm. Make zone_free_item simpler now that callers can manage more stats. - Check for these cache-only zones in the public APIs and debugging code by checking zone_first_keg() against NULL. Sponsored by: EMC / Isilong Storage Division
2013-06-17 03:43:47 +00:00
zone_free_item(slabzone, slab, NULL, SKIP_NONE);
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Make M_ZERO flag work correctly on UMA_ZONE_PCPU zones. Sponsored by: Nginx, Inc.
2014-02-10 19:48:26 +00:00
static void
uma_zero_item(void *item, uma_zone_t zone)
{
Replace a number of conflations of mp_ncpus and mp_maxid with either mp_maxid or CPU_FOREACH() as appropriate. This fixes a number of places in the kernel that assumed CPU IDs are dense in [0, mp_ncpus) and would try, for example, to run tasks on CPUs that did not exist or to allocate too few buffers on systems with sparse CPU IDs in which there are holes in the range and mp_maxid > mp_ncpus. Such circumstances generally occur on systems with SMT, but on which SMT is disabled. This patch restores system operation at least on POWER8 systems configured in this way. There are a number of other places in the kernel with potential problems in these situations, but where sparse CPU IDs are not currently known to occur, mostly in the ARM machine-dependent code. These will be fixed in a follow-up commit after the stable/11 branch. PR: kern/210106 Reviewed by: jhb Approved by: re (glebius)
2016-07-06 14:09:49 +00:00
int i;
Make M_ZERO flag work correctly on UMA_ZONE_PCPU zones. Sponsored by: Nginx, Inc.
2014-02-10 19:48:26 +00:00
if (zone->uz_flags & UMA_ZONE_PCPU) {
Replace a number of conflations of mp_ncpus and mp_maxid with either mp_maxid or CPU_FOREACH() as appropriate. This fixes a number of places in the kernel that assumed CPU IDs are dense in [0, mp_ncpus) and would try, for example, to run tasks on CPUs that did not exist or to allocate too few buffers on systems with sparse CPU IDs in which there are holes in the range and mp_maxid > mp_ncpus. Such circumstances generally occur on systems with SMT, but on which SMT is disabled. This patch restores system operation at least on POWER8 systems configured in this way. There are a number of other places in the kernel with potential problems in these situations, but where sparse CPU IDs are not currently known to occur, mostly in the ARM machine-dependent code. These will be fixed in a follow-up commit after the stable/11 branch. PR: kern/210106 Reviewed by: jhb Approved by: re (glebius)
2016-07-06 14:09:49 +00:00
CPU_FOREACH(i)
Make M_ZERO flag work correctly on UMA_ZONE_PCPU zones. Sponsored by: Nginx, Inc.
2014-02-10 19:48:26 +00:00
bzero(zpcpu_get_cpu(item, i), zone->uz_size);
} else
bzero(item, zone->uz_size);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
void
uma_print_stats(void)
{
zone_foreach(uma_print_zone);
}
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
static void
slab_print(uma_slab_t slab)
{
- Convert the slab free item list from a linked array of indices to a bitmap using sys/bitset. This is much simpler, has lower space overhead and is cheaper in most cases. - Use a second bitmap for invariants asserts and improve the quality of the asserts as well as the number of erroneous conditions that we will catch. - Drastically simplify sizing code. Special case refcnt zones since they will be going away. - Update stale comments. Sponsored by: EMC / Isilon Storage Division
2013-06-13 21:05:38 +00:00
printf("slab: keg %p, data %p, freecount %d\n",
slab->us_keg, slab->us_data, slab->us_freecount);
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
}
static void
cache_print(uma_cache_t cache)
{
Mechanical whitespace cleanup.
2004-01-30 16:26:29 +00:00
printf("alloc: %p(%d), free: %p(%d)\n",
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
cache->uc_allocbucket,
cache->uc_allocbucket?cache->uc_allocbucket->ub_cnt:0,
cache->uc_freebucket,
cache->uc_freebucket?cache->uc_freebucket->ub_cnt:0);
}
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
static void
uma_print_keg(uma_keg_t keg)
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
{
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
uma_slab_t slab;
Print flags as hex instead of an integer. PR: kern/168210 Submitted by: linimon Reviewed by: alc Approved by: cperciva MFC after: 3 days
2012-10-22 02:11:57 +00:00
printf("keg: %s(%p) size %d(%d) flags %#x ipers %d ppera %d "
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
"out %d free %d limit %d\n",
keg->uk_name, keg, keg->uk_size, keg->uk_rsize, keg->uk_flags,
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
keg->uk_ipers, keg->uk_ppera,
uma: fix pages <-> items conversions at several places Those places were not taking into account uk_ppera. At present one allocation is always used by one slab, so uk_ppera must be used to convert between pages and slabs. uk_ipers is used to convert between slabs and items. MFC after: 1 month (if ever)
2017-03-11 16:43:38 +00:00
(keg->uk_pages / keg->uk_ppera) * keg->uk_ipers - keg->uk_free,
keg->uk_free, (keg->uk_maxpages / keg->uk_ppera) * keg->uk_ipers);
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
printf("Part slabs:\n");
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_FOREACH(slab, &keg->uk_part_slab, us_link)
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
slab_print(slab);
printf("Free slabs:\n");
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_FOREACH(slab, &keg->uk_free_slab, us_link)
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
slab_print(slab);
printf("Full slabs:\n");
Bring in mbuma to replace mballoc. mbuma is an Mbuf & Cluster allocator built on top of a number of extensions to the UMA framework, all included herein. Extensions to UMA worth noting: - Better layering between slab <-> zone caches; introduce Keg structure which splits off slab cache away from the zone structure and allows multiple zones to be stacked on top of a single Keg (single type of slab cache); perhaps we should look into defining a subset API on top of the Keg for special use by malloc(9), for example. - UMA_ZONE_REFCNT zones can now be added, and reference counters automagically allocated for them within the end of the associated slab structures. uma_find_refcnt() does a kextract to fetch the slab struct reference from the underlying page, and lookup the corresponding refcnt. mbuma things worth noting: - integrates mbuf & cluster allocations with extended UMA and provides caches for commonly-allocated items; defines several zones (two primary, one secondary) and two kegs. - change up certain code paths that always used to do: m_get() + m_clget() to instead just use m_getcl() and try to take advantage of the newly defined secondary Packet zone. - netstat(1) and systat(1) quickly hacked up to do basic stat reporting but additional stats work needs to be done once some other details within UMA have been taken care of and it becomes clearer to how stats will work within the modified framework. From the user perspective, one implication is that the NMBCLUSTERS compile-time option is no longer used. The maximum number of clusters is still capped off according to maxusers, but it can be made unlimited by setting the kern.ipc.nmbclusters boot-time tunable to zero. Work should be done to write an appropriate sysctl handler allowing dynamic tuning of kern.ipc.nmbclusters at runtime. Additional things worth noting/known issues (READ): - One report of 'ips' (ServeRAID) driver acting really slow in conjunction with mbuma. Need more data. Latest report is that ips is equally sucking with and without mbuma. - Giant leak in NFS code sometimes occurs, can't reproduce but currently analyzing; brueffer is able to reproduce but THIS IS NOT an mbuma-specific problem and currently occurs even WITHOUT mbuma. - Issues in network locking: there is at least one code path in the rip code where one or more locks are acquired and we end up in m_prepend() with M_WAITOK, which causes WITNESS to whine from within UMA. Current temporary solution: force all UMA allocations to be M_NOWAIT from within UMA for now to avoid deadlocks unless WITNESS is defined and we can determine with certainty that we're not holding any locks when we're M_WAITOK. - I've seen at least one weird socketbuffer empty-but- mbuf-still-attached panic. I don't believe this to be related to mbuma but please keep your eyes open, turn on debugging, and capture crash dumps. This change removes more code than it adds. A paper is available detailing the change and considering various performance issues, it was presented at BSDCan2004: http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf Please read the paper for Future Work and implementation details, as well as credits. Testing and Debugging: rwatson, brueffer, Ketrien I. Saihr-Kesenchedra, ... Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00
LIST_FOREACH(slab, &keg->uk_full_slab, us_link)
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
slab_print(slab);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
}
void
uma_print_zone(uma_zone_t zone)
{
uma_cache_t cache;
uma_klink_t kl;
int i;
Print flags as hex instead of an integer. PR: kern/168210 Submitted by: linimon Reviewed by: alc Approved by: cperciva MFC after: 3 days
2012-10-22 02:11:57 +00:00
printf("zone: %s(%p) size %d flags %#x\n",
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
zone->uz_name, zone, zone->uz_size, zone->uz_flags);
LIST_FOREACH(kl, &zone->uz_kegs, kl_link)
uma_print_keg(kl->kl_keg);
Update several places that iterate over CPUs to use CPU_FOREACH().
2010-06-11 18:46:34 +00:00
CPU_FOREACH(i) {
- Replace the local maxcpu with mp_maxid. Previously, if mp_maxid was equal to MAXCPU, we would overrun the pcpu_mtx array because maxcpu was calculated incorrectly. - Add some more debugging code so that memory leaks at the time of uma_zdestroy() are more easily diagnosed. Approved by: re (rwatson)
2003-11-30 08:04:01 +00:00
cache = &zone->uz_cpu[i];
printf("CPU %d Cache:\n", i);
cache_print(cache);
}
This is the first part of the new kernel memory allocator. This replaces malloc(9) and vm_zone with a slab like allocator. Reviewed by: arch@
2002-03-19 09:11:49 +00:00
}
Fix build of uma_core.c when DDB is not compiled into the kernel by making uma_zone_sumstat() ifdef DDB, as it's only used with DDB now. Submitted by: Wolfram Fenske <Wolfram.Fenske at Student.Uni-Magdeburg.DE>
2006-07-18 01:13:18 +00:00
#ifdef DDB
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
/*
* Generate statistics across both the zone and its per-cpu cache's. Return
* desired statistics if the pointer is non-NULL for that statistic.
*
* Note: does not update the zone statistics, as it can't safely clear the
* per-CPU cache statistic.
*
* XXXRW: Following the uc_allocbucket and uc_freebucket pointers here isn't
* safe from off-CPU; we should modify the caches to track this information
* directly so that we don't have to.
*/
static void
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uma_zone_sumstat(uma_zone_t z, int *cachefreep, uint64_t *allocsp,
uint64_t *freesp, uint64_t *sleepsp)
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
{
uma_cache_t cache;
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint64_t allocs, frees, sleeps;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
int cachefree, cpu;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
allocs = frees = sleeps = 0;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
cachefree = 0;
Update several places that iterate over CPUs to use CPU_FOREACH().
2010-06-11 18:46:34 +00:00
CPU_FOREACH(cpu) {
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
cache = &z->uz_cpu[cpu];
if (cache->uc_allocbucket != NULL)
cachefree += cache->uc_allocbucket->ub_cnt;
if (cache->uc_freebucket != NULL)
cachefree += cache->uc_freebucket->ub_cnt;
allocs += cache->uc_allocs;
frees += cache->uc_frees;
}
allocs += z->uz_allocs;
frees += z->uz_frees;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
sleeps += z->uz_sleeps;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
if (cachefreep != NULL)
*cachefreep = cachefree;
if (allocsp != NULL)
*allocsp = allocs;
if (freesp != NULL)
*freesp = frees;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
if (sleepsp != NULL)
*sleepsp = sleeps;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
}
Fix build of uma_core.c when DDB is not compiled into the kernel by making uma_zone_sumstat() ifdef DDB, as it's only used with DDB now. Submitted by: Wolfram Fenske <Wolfram.Fenske at Student.Uni-Magdeburg.DE>
2006-07-18 01:13:18 +00:00
#endif /* DDB */
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
static int
sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
{
uma_keg_t kz;
uma_zone_t z;
int count;
count = 0;
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_rlock(&uma_rwlock);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
LIST_FOREACH(kz, &uma_kegs, uk_link) {
LIST_FOREACH(z, &kz->uk_zones, uz_link)
count++;
}
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_runlock(&uma_rwlock);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
return (sysctl_handle_int(oidp, &count, 0, req));
}
static int
sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
{
struct uma_stream_header ush;
struct uma_type_header uth;
struct uma_percpu_stat ups;
uma_bucket_t bucket;
struct sbuf sbuf;
uma_cache_t cache;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_klink_t kl;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
uma_keg_t kz;
uma_zone_t z;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
uma_keg_t k;
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
int count, error, i;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
Explicitly wire the user buffer rather than doing it implicitly in sbuf_new_for_sysctl(9). This allows using an sbuf with a SYSCTL_OUT drain for extremely large amounts of data where the caller knows that appropriate references are held, and sleeping is not an issue. Inspired by: rwatson
2011-01-27 00:34:12 +00:00
error = sysctl_wire_old_buffer(req, 0);
if (error != 0)
return (error);
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
Set the SBUF_INCLUDENUL flag in sbuf_new_for_sysctl() so that sysctl strings returned to userland include the nulterm byte. Some uses of sbuf_new_for_sysctl() write binary data rather than strings; clear the SBUF_INCLUDENUL flag after calling sbuf_new_for_sysctl() in those cases. (Note that the sbuf code still automatically adds a nulterm byte in sbuf_finish(), but since it's not included in the length it won't get copied to userland along with the binary data.) Remove explicit adding of a nulterm byte in a couple places now that it gets done automatically by the sbuf drain code. PR: 195668
2015-03-14 17:08:28 +00:00
sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
Revert r212370, as it causes a LOR on powerpc. powerpc does a few unexpected things in copyout(9) and so wiring the user buffer is not sufficient to perform a copyout(9) while holding a random mutex. Requested by: nwhitehorn
2010-09-13 18:48:23 +00:00
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
count = 0;
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_rlock(&uma_rwlock);
Revert r212370, as it causes a LOR on powerpc. powerpc does a few unexpected things in copyout(9) and so wiring the user buffer is not sufficient to perform a copyout(9) while holding a random mutex. Requested by: nwhitehorn
2010-09-13 18:48:23 +00:00
LIST_FOREACH(kz, &uma_kegs, uk_link) {
LIST_FOREACH(z, &kz->uk_zones, uz_link)
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
count++;
Revert r212370, as it causes a LOR on powerpc. powerpc does a few unexpected things in copyout(9) and so wiring the user buffer is not sufficient to perform a copyout(9) while holding a random mutex. Requested by: nwhitehorn
2010-09-13 18:48:23 +00:00
}
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
/*
* Insert stream header.
*/
bzero(&ush, sizeof(ush));
ush.ush_version = UMA_STREAM_VERSION;
Use mp_maxid in preference to MAXCPU when creating exports of UMA per-CPU cache statistics. UMA sizes the cache array based on the number of CPUs at boot (mp_maxid + 1), and iterating based on MAXCPU could read off the end of the array (into the next zone). Reported by: yongari MFC after: 1 week
2005-07-16 11:03:06 +00:00
ush.ush_maxcpus = (mp_maxid + 1);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
ush.ush_count = count;
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
LIST_FOREACH(kz, &uma_kegs, uk_link) {
LIST_FOREACH(z, &kz->uk_zones, uz_link) {
bzero(&uth, sizeof(uth));
ZONE_LOCK(z);
Rename UMA_MAX_NAME to UTH_MAX_NAME, since it's a maximum in the monitoring API, which might or might not be the same as the internal maximum (currently none). Export flag information on UMA zones -- in particular, whether or not this is a secondary zone, and so the keg free count should be considered in that light. MFC after: 1 day
2005-07-25 00:47:32 +00:00
strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
uth.uth_align = kz->uk_align;
uth.uth_size = kz->uk_size;
uth.uth_rsize = kz->uk_rsize;
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
LIST_FOREACH(kl, &z->uz_kegs, kl_link) {
k = kl->kl_keg;
uth.uth_maxpages += k->uk_maxpages;
uth.uth_pages += k->uk_pages;
uth.uth_keg_free += k->uk_free;
uth.uth_limit = (k->uk_maxpages / k->uk_ppera)
* k->uk_ipers;
}
Rename UMA_MAX_NAME to UTH_MAX_NAME, since it's a maximum in the monitoring API, which might or might not be the same as the internal maximum (currently none). Export flag information on UMA zones -- in particular, whether or not this is a secondary zone, and so the keg free count should be considered in that light. MFC after: 1 day
2005-07-25 00:47:32 +00:00
/*
* A zone is secondary is it is not the first entry
* on the keg's zone list.
*/
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
Rename UMA_MAX_NAME to UTH_MAX_NAME, since it's a maximum in the monitoring API, which might or might not be the same as the internal maximum (currently none). Export flag information on UMA zones -- in particular, whether or not this is a secondary zone, and so the keg free count should be considered in that light. MFC after: 1 day
2005-07-25 00:47:32 +00:00
(LIST_FIRST(&kz->uk_zones) != z))
uth.uth_zone_flags = UTH_ZONE_SECONDARY;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
uth.uth_zone_free += bucket->ub_cnt;
uth.uth_allocs = z->uz_allocs;
uth.uth_frees = z->uz_frees;
Track UMA(9) allocation failures by zone, and export via sysctl. Requested by: victor cruceru <victor dot cruceru at gmail dot com> MFC after: 1 week
2005-07-15 23:34:39 +00:00
uth.uth_fails = z->uz_fails;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
uth.uth_sleeps = z->uz_sleeps;
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
/*
Move the unlocking of the zone mutex in sysctl_vm_zone_stats() so that it covers the following of the uc_alloc/freebucket cache pointers. Originally, I felt that the race wasn't helped by holding the mutex, hence a comment in the code and not holding it across the cache access. However, it does improve consistency, as while it doesn't prevent bucket exchange, it does prevent bucket pointer invalidation. So a race in gathering cache free space statistics still can occur, but not one that follows an invalid bucket pointer, if the mutex is held. Submitted by: yongari MFC after: 1 week
2005-07-16 09:40:34 +00:00
* While it is not normally safe to access the cache
* bucket pointers while not on the CPU that owns the
* cache, we only allow the pointers to be exchanged
* without the zone lock held, not invalidated, so
* accept the possible race associated with bucket
* exchange during monitoring.
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
*/
Use mp_maxid in preference to MAXCPU when creating exports of UMA per-CPU cache statistics. UMA sizes the cache array based on the number of CPUs at boot (mp_maxid + 1), and iterating based on MAXCPU could read off the end of the array (into the next zone). Reported by: yongari MFC after: 1 week
2005-07-16 11:03:06 +00:00
for (i = 0; i < (mp_maxid + 1); i++) {
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
bzero(&ups, sizeof(ups));
if (kz->uk_flags & UMA_ZFLAG_INTERNAL)
goto skip;
Skip per-cpu caches associated with absent CPUs when generating a memory statistics record stream via sysctl. MFC after: 3 days
2006-02-11 19:20:56 +00:00
if (CPU_ABSENT(i))
goto skip;
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
cache = &z->uz_cpu[i];
if (cache->uc_allocbucket != NULL)
ups.ups_cache_free +=
cache->uc_allocbucket->ub_cnt;
if (cache->uc_freebucket != NULL)
ups.ups_cache_free +=
cache->uc_freebucket->ub_cnt;
ups.ups_allocs = cache->uc_allocs;
ups.ups_frees = cache->uc_frees;
skip:
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
(void)sbuf_bcat(&sbuf, &ups, sizeof(ups));
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
}
Move the unlocking of the zone mutex in sysctl_vm_zone_stats() so that it covers the following of the uc_alloc/freebucket cache pointers. Originally, I felt that the race wasn't helped by holding the mutex, hence a comment in the code and not holding it across the cache access. However, it does improve consistency, as while it doesn't prevent bucket exchange, it does prevent bucket pointer invalidation. So a race in gathering cache free space statistics still can occur, but not one that follows an invalid bucket pointer, if the mutex is held. Submitted by: yongari MFC after: 1 week
2005-07-16 09:40:34 +00:00
ZONE_UNLOCK(z);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
}
}
Change the UMA mutex into a rwlock Acquire the lock in read mode when just needed to ensure the stability of the keg list. The UMA lock may be held for a long time (relatively speaking) in uma_reclaim() on machines with lots of zones/kegs. If the uma_timeout() would fire during that period, subsequent callouts on that CPU may be significantly delayed. Reviewed by: jhb
2014-10-05 21:34:56 +00:00
rw_runlock(&uma_rwlock);
Re-add r212370 now that the LOR in powerpc64 has been resolved: Add a drain function for struct sysctl_req, and use it for a variety of handlers, some of which had to do awkward things to get a large enough SBUF_FIXEDLEN buffer. Note that some sysctl handlers were explicitly outputting a trailing NUL byte. This behaviour was preserved, though it should not be necessary. Reviewed by: phk (original patch)
2010-09-16 16:13:12 +00:00
error = sbuf_finish(&sbuf);
sbuf_delete(&sbuf);
Introduce a new sysctl, vm.zone_stats, which exports UMA(9) allocator statistics via a binary structure stream: - Add structure 'uma_stream_header', which defines a stream version, definition of MAXCPUs used in the stream, and the number of zone records in the stream. - Add structure 'uma_type_header', which defines the name, alignment, size, resource allocation limits, current pages allocated, preferred bucket size, and central zone + keg statistics. - Add structure 'uma_percpu_stat', which, for each per-CPU cache, includes the number of allocations and frees, as well as the number of free items in the cache. - When the sysctl is queried, return a stream header, followed by a series of type descriptions, each consisting of a type header followed by a series of MAXCPUs uma_percpu_stat structures holding per-CPU allocation information. Typical values of MAXCPU will be 1 (UP compiled kernel) and 16 (SMP compiled kernel). This query mechanism allows user space monitoring tools to extract memory allocation statistics in a machine-readable form, and to do so at a per-CPU granularity, allowing monitoring of allocation patterns across CPUs in order to better understand the distribution of work and memory flow over multiple CPUs. While here, also export the number of UMA zones as a sysctl vm.uma_count, in order to assist in sizing user swpace buffers to receive the stream. A follow-up commit of libmemstat(3), a library to monitor kernel memory allocation, will occur in the next few days. This change directly supports converting netstat(1)'s "-mb" mode to using UMA-sourced stats rather than separately maintained mbuf allocator statistics. MFC after: 1 week
2005-07-14 16:35:13 +00:00
return (error);
}
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
Provide macros that allow easily export uma(9) zone limits and current usage via sysctl(9): SYSCTL_UMA_MAX() SYSCTL_ADD_UMA_MAX() SYSCTL_UMA_CUR() SYSCTL_ADD_UMA_CUR() Sponsored by: Nginx, Inc.
2014-02-07 14:29:03 +00:00
int
sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
{
uma_zone_t zone = *(uma_zone_t *)arg1;
UMA zone limit can be lowered, so remove protection against from the sysctl_handle_uma_zone_max(). Sponsored by: Nginx, Inc.
2015-04-10 06:56:49 +00:00
int error, max;
Provide macros that allow easily export uma(9) zone limits and current usage via sysctl(9): SYSCTL_UMA_MAX() SYSCTL_ADD_UMA_MAX() SYSCTL_UMA_CUR() SYSCTL_ADD_UMA_CUR() Sponsored by: Nginx, Inc.
2014-02-07 14:29:03 +00:00
UMA zone limit can be lowered, so remove protection against from the sysctl_handle_uma_zone_max(). Sponsored by: Nginx, Inc.
2015-04-10 06:56:49 +00:00
max = uma_zone_get_max(zone);
Provide macros that allow easily export uma(9) zone limits and current usage via sysctl(9): SYSCTL_UMA_MAX() SYSCTL_ADD_UMA_MAX() SYSCTL_UMA_CUR() SYSCTL_ADD_UMA_CUR() Sponsored by: Nginx, Inc.
2014-02-07 14:29:03 +00:00
error = sysctl_handle_int(oidp, &max, 0, req);
if (error || !req->newptr)
return (error);
uma_zone_set_max(zone, max);
return (0);
}
int
sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
{
uma_zone_t zone = *(uma_zone_t *)arg1;
int cur;
cur = uma_zone_get_cur(zone);
return (sysctl_handle_int(oidp, &cur, 0, req));
}
Move uma_dbg_alloc() and uma_dbg_free() into uma_core.c, which allows to make uma_dbg.h not depend on uma_int.h, which allows to uninclude uma_int.h from the mbuf(9) allocator.
2016-02-03 22:02:36 +00:00
#ifdef INVARIANTS
static uma_slab_t
uma_dbg_getslab(uma_zone_t zone, void *item)
{
uma_slab_t slab;
uma_keg_t keg;
uint8_t *mem;
mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
if (zone->uz_flags & UMA_ZONE_VTOSLAB) {
slab = vtoslab((vm_offset_t)mem);
} else {
/*
* It is safe to return the slab here even though the
* zone is unlocked because the item's allocation state
* essentially holds a reference.
*/
ZONE_LOCK(zone);
keg = LIST_FIRST(&zone->uz_kegs)->kl_keg;
if (keg->uk_flags & UMA_ZONE_HASH)
slab = hash_sfind(&keg->uk_hash, mem);
else
slab = (uma_slab_t)(mem + keg->uk_pgoff);
ZONE_UNLOCK(zone);
}
return (slab);
}
/*
* Set up the slab's freei data such that uma_dbg_free can function.
*
*/
static void
uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
{
uma_keg_t keg;
int freei;
if (zone_first_keg(zone) == NULL)
return;
if (slab == NULL) {
slab = uma_dbg_getslab(zone, item);
if (slab == NULL)
panic("uma: item %p did not belong to zone %s\n",
item, zone->uz_name);
}
keg = slab->us_keg;
freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
if (BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)\n",
item, zone, zone->uz_name, slab, freei);
BIT_SET_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
return;
}
/*
* Verifies freed addresses. Checks for alignment, valid slab membership
* and duplicate frees.
*
*/
static void
uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
{
uma_keg_t keg;
int freei;
if (zone_first_keg(zone) == NULL)
return;
if (slab == NULL) {
slab = uma_dbg_getslab(zone, item);
if (slab == NULL)
panic("uma: Freed item %p did not belong to zone %s\n",
item, zone->uz_name);
}
keg = slab->us_keg;
freei = ((uintptr_t)item - (uintptr_t)slab->us_data) / keg->uk_rsize;
if (freei >= keg->uk_ipers)
panic("Invalid free of %p from zone %p(%s) slab %p(%d)\n",
item, zone, zone->uz_name, slab, freei);
if (((freei * keg->uk_rsize) + slab->us_data) != item)
panic("Unaligned free of %p from zone %p(%s) slab %p(%d)\n",
item, zone, zone->uz_name, slab, freei);
if (!BIT_ISSET(SLAB_SETSIZE, freei, &slab->us_debugfree))
panic("Duplicate free of %p from zone %p(%s) slab %p(%d)\n",
item, zone, zone->uz_name, slab, freei);
BIT_CLR_ATOMIC(SLAB_SETSIZE, freei, &slab->us_debugfree);
}
#endif /* INVARIANTS */
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
#ifdef DDB
DB_SHOW_COMMAND(uma, db_show_uma)
{
Convert UMA code to C99 uintXX_t types.
2013-04-09 17:43:48 +00:00
uint64_t allocs, frees, sleeps;
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
uma_bucket_t bucket;
uma_keg_t kz;
uma_zone_t z;
int cachefree;
- Add bucket size column to `show uma` DDB command. - Add `show umacache` command to show alike stats for cache-only UMA zones.
2013-11-28 19:20:49 +00:00
db_printf("%18s %8s %8s %8s %12s %8s %8s\n", "Zone", "Size", "Used",
"Free", "Requests", "Sleeps", "Bucket");
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
LIST_FOREACH(kz, &uma_kegs, uk_link) {
LIST_FOREACH(z, &kz->uk_zones, uz_link) {
if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
allocs = z->uz_allocs;
frees = z->uz_frees;
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
sleeps = z->uz_sleeps;
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
cachefree = 0;
} else
uma_zone_sumstat(z, &cachefree, &allocs,
Add a new column to the output of vmstat -z to indicate the number of times the system was forced to sleep when requesting a new allocation. Expand the debugger hook, db_show_uma, to display these results as well. This has proven to be very useful in out of memory situations when it is not known why systems have become sluggish or fail in odd ways. Reviewed by: rwatson alc Approved by: scottl (mentor) peter Obtained from: Yahoo Inc.
2010-06-15 19:28:37 +00:00
&frees, &sleeps);
- Make the keg abstraction more complete. Permit a zone to have multiple backend kegs so it may source compatible memory from multiple backends. This is useful for cases such as NUMA or different layouts for the same memory type. - Provide a new api for adding new backend kegs to secondary zones. - Provide a new flag for adjusting the layout of zones to stagger allocations better across cache lines. Sponsored by: Nokia
2009-01-25 09:11:24 +00:00
if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
(LIST_FIRST(&kz->uk_zones) != z)))
cachefree += kz->uk_free;
Refine UMA bucket allocation to reduce space consumption and improve performance. - Always free to the alloc bucket if there is space. This gives LIFO allocation order to improve hot-cache performance. This also allows for zones with a single bucket per-cpu rather than a pair if the entire working set fits in one bucket. - Enable per-cpu caches of buckets. To prevent recursive bucket allocation one bucket zone still has per-cpu caches disabled. - Pick the initial bucket size based on a table driven maximum size per-bucket rather than the number of items per-page. This gives more sane initial sizes. - Only grow the bucket size when we face contention on the zone lock, this causes bucket sizes to grow more slowly. - Adjust the number of items per-bucket to account for the header space. This packs the buckets more efficiently per-page while making them not quite powers of two. - Eliminate the per-zone free bucket list. Always return buckets back to the bucket zone. This ensures that as zones grow into larger bucket sizes they eventually discard the smaller sizes. It persists fewer buckets in the system. The locking is slightly trickier. - Only switch buckets in zalloc, not zfree, this eliminates pathological cases where we ping-pong between two buckets. - Ensure that the thread that fills a new bucket gets to allocate from it to give a better upper bound on allocation time. Sponsored by: EMC / Isilon Storage Division
2013-06-18 04:50:20 +00:00
LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
cachefree += bucket->ub_cnt;
- Add bucket size column to `show uma` DDB command. - Add `show umacache` command to show alike stats for cache-only UMA zones.
2013-11-28 19:20:49 +00:00
db_printf("%18s %8ju %8jd %8d %12ju %8ju %8u\n",
z->uz_name, (uintmax_t)kz->uk_size,
Better align output of "show uma" by moving from displaying the basic counters of allocs/frees/use for each zone to the same statistics shown by userspace "vmstat -z". MFC after: 3 days
2006-10-26 12:55:32 +00:00
(intmax_t)(allocs - frees), cachefree,
- Add bucket size column to `show uma` DDB command. - Add `show umacache` command to show alike stats for cache-only UMA zones.
2013-11-28 19:20:49 +00:00
(uintmax_t)allocs, sleeps, z->uz_count);
Honor db_pager_quit in 'show uma' and 'show malloc'. MFC after: 1 month
2012-07-02 16:14:52 +00:00
if (db_pager_quit)
return;
Add a "show uma" command to DDB, which prints out the current stats for available UMA zones. Quite useful for post-mortem debugging of memory leaks without a dump device configured on a panicked box. MFC after: 2 weeks
2005-10-20 16:39:33 +00:00
}
}
}
- Add bucket size column to `show uma` DDB command. - Add `show umacache` command to show alike stats for cache-only UMA zones.
2013-11-28 19:20:49 +00:00
DB_SHOW_COMMAND(umacache, db_show_umacache)
{
uint64_t allocs, frees;
uma_bucket_t bucket;
uma_zone_t z;
int cachefree;
db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
"Requests", "Bucket");
LIST_FOREACH(z, &uma_cachezones, uz_link) {
uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL);
LIST_FOREACH(bucket, &z->uz_buckets, ub_link)
cachefree += bucket->ub_cnt;
db_printf("%18s %8ju %8jd %8d %12ju %8u\n",
z->uz_name, (uintmax_t)z->uz_size,
(intmax_t)(allocs - frees), cachefree,
(uintmax_t)allocs, z->uz_count);
if (db_pager_quit)
return;
}
}
Move uma_dbg_alloc() and uma_dbg_free() into uma_core.c, which allows to make uma_dbg.h not depend on uma_int.h, which allows to uninclude uma_int.h from the mbuf(9) allocator.
2016-02-03 22:02:36 +00:00
#endif /* DDB */
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