Commit Graph

22 Commits

Author SHA1 Message Date
Jeff Roberson
e20a199fd5 - 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
Robert Watson
08ecce74bc 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
Mike Silbersack
cb6e5c1aba Change the panic in trash_ctor into just a printf for now. Once the reports
of panics in trash_ctor relating to mbufs have been examined and a fix
found, this will be turned back into a panic.

Approved by: re (rwatson)
2005-06-26 23:44:07 +00:00
Bosko Milekic
8076cb5289 Well, it seems that I pre-maturely removed the "All rights reserved"
statement from some files, so re-add it for the moment, until the
related legalese is sorted out.  This change affects:

sys/kern/kern_mbuf.c
sys/vm/memguard.c
sys/vm/memguard.h
sys/vm/uma.h
sys/vm/uma_core.c
sys/vm/uma_dbg.c
sys/vm/uma_dbg.h
sys/vm/uma_int.h
2005-02-16 21:45:59 +00:00
Warner Losh
60727d8b86 /* -> /*- for license, minor formatting changes 2005-01-07 02:29:27 +00:00
Bosko Milekic
7b8712053c Add my copyright and update Jeff's copyright on UMA source files,
as per his request.

Discussed with: Jeffrey Roberson
2004-12-26 00:35:12 +00:00
Brian Feldman
ab14a3f7aa Fix critical stability problems that can cause UMA mbuf cluster
state management corruption, mbuf leaks, general mbuf corruption,
and at least on i386 a first level splash damage radius that
encompasses up to about half a megabyte of the memory after
an mbuf cluster's allocation slab.  In short, this has caused
instability nightmares anywhere the right kind of network traffic
is present.

When the polymorphic refcount slabs were added to UMA, the new types
were not used pervasively.  In particular, the slab management
structure was turned into one for refcounts, and one for non-refcounts
(supposed to be mostly like the old slab management structure),
but the latter was almost always used through out.  In general, every
access to zones with UMA_ZONE_REFCNT turned on corrupted the
"next free" slab offset offset and the refcount with each other and
with other allocations (on i386, 2 mbuf clusters per 4096 byte slab).

Fix things so that the right type is used to access refcounted zones
where it was not before.  There are additional errors in gross
overestimation of padding, it seems, that would cause a large kegs
(nee zones) to be allocated when small ones would do.  Unless I have
analyzed this incorrectly, it is not directly harmful.
2004-10-08 20:19:29 +00:00
Brian Feldman
b23f72e98a * 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
Bosko Milekic
099a0e588c 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
Poul-Henning Kamp
e0f86251a7 Provide a bit more help with "memory overwritten after free" style bugs. 2003-09-27 21:33:13 +00:00
Jeff Roberson
b60f5b794e - 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
David E. O'Brien
874651b13c Use __FBSDID(). 2003-06-11 23:50:51 +00:00
Matt Jacob
81f71edaec atomic_set_8 isn't MI. Instead, follow Jake's suggestions about
ZONE_LOCK.
2002-11-11 11:50:03 +00:00
Matt Jacob
7ca05a39c7 Use atomic_set_8 on the us_freelist maps as they are not otherwise
protected. Furthermore, in some RISC architectures with no normal
byte operations, the surrounding 3 bytes are also affected by the
read-modify-write that has to occur.
2002-11-10 16:16:44 +00:00
Jeff Roberson
f461cf2297 - Use my freebsd email alias in the copyright.
- Remove redundant instances of my email alias in the file summary.
2002-09-19 06:05:32 +00:00
Jeff Roberson
99571dc345 - 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
Jeff Roberson
f5118d6aaf Remove unnecessary includes. 2002-07-05 05:16:19 +00:00
Peter Wemm
7550be9c57 The kernel printf does not have %i 2002-05-29 08:25:13 +00:00
Jeff Roberson
8f70816cf2 Hide a pointer to the malloc_type bucket at the end of the freed memory. If
this memory is modified after it has been freed we can now report it's
previous owner.
2002-05-02 09:07:04 +00:00
Jeff Roberson
5a34a9f089 malloc/free(9) no longer require Giant. Use the malloc_mtx to protect the
mallochash.  Mallochash is going to go away as soon as I introduce the
kfree/kmalloc api and partially overhaul the malloc wrapper.  This can't happen
until all users of the malloc api that expect memory to be aligned on the size
of the allocation are fixed.
2002-05-02 07:22:19 +00:00
Jeff Roberson
639c9550fb 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
Jeff Roberson
8efc4eff00 Add a new UMA debugging facility. This will overwrite freed memory with
0xdeadc0de and then check for it just before memory is handed off as part
of a new request.  This will catch any post free/pre alloc modification of
memory, as well as introduce errors for anything that tries to dereference
it as a pointer.

This code takes the form of special init, fini, ctor and dtor routines that
are specificly used by malloc.  It is in a seperate file because additional
debugging aids will want to live here as well.
2002-04-30 07:54:25 +00:00