expression howmany(BBSIZE, PAGE_SIZE), where BBSIZE is the size of the
boot block area. That can be less than 2 if PAGE_SIZE is big.
swapon(8) has an option to trim (delete) all the blocks of a device at
startup. However, if the first of those blocks is a bsd label, then
trimming those blocks is destructive. Change swapon to leave the
first BBSIZE bytes untrimmed.
Update manual pages to reflect changes in how swapon and how it may be
used, espeically in association with savecore.
Reviewed by: alc
Approved by: markj (mentor)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D21191
counter, and the final freeing of freed swap blocks, outside the
region where an object lock is held. Correct some style(9) and
spelling errors. Change a panic() to a KASSERT(). Change a boolean_t
to a bool.
Suggested by: alc
Reviewed by: alc
Approved by: kib, markj (mentors)
Differential Revision: https://reviews.freebsd.org/D21093
comment. Rewrite that comment to improve its clarity.
Reported by: cem
Reviewed by: alc, cem
Approved by: kib, markj (mentors, implicit)
Differential Revision: https://reviews.freebsd.org/D20871
after the one where the possible block allocation begins, and allocate
a larger number of blocks than the current limit. This does not affect
the limit on minimum allocation size, which still cannot exceed
BLIST_MAX_ALLOC.
Use this change to modify swp_pager_getswapspace and its callers, so
that they can allocate more than BLIST_MAX_ALLOC blocks if they are
available.
Tested by: pho
Approved by: markj (mentor)
Differential Revision: https://reviews.freebsd.org/D20579
swap_pager_swapoff_object and swp_pager_force_pagein so that they can
page in multiple pages at a time to a swap device, rather than doing
one I/O operation for each page.
Tested by: pho
Submitted by: ota_j.email.ne.jp (Yoshihiro Ota)
Reviewed by: alc, markj, kib
Approved by: kib, markj (mentors)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20635
sw_flags is set to the function argument several lines later.
Reported by: danfe using PVS-studio
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Use it instead of accessing the wire_count field directly. No
functional change intended.
Reviewed by: alc, kib
MFC after: 1 week
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20485
This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.
EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).
As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.
LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).
No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.
the allocation request, so that the blocks allocated are from the next
set of free blocks big enough to satisfy the minimum requirements of
the request, and the number of blocks allocated are as many as
possible, up to the specified maximum. The implementation of
swp_pager_getswapspace uses this parameter to ask for a number of
blocks between the new halved request size and the previous failed
request size. Thus a request for 32 blocks may fail, but instead of
getting only 16 blocks instead, the caller asks for 16 to 31 next, and
might get 19 or 27, which is closer to what they originally wanted.
I expect this to lead to bigger block allocations and less block
fragmentation, at least in some cases.
Approved by: kib (mentor)
Differential Revision: https://reviews.freebsd.org/D20001
requested, or none, and in the latter case it is up to them to pick a
smaller request to make - which they always do by halving the failed
request. This change to swp_pager_getswapspace leaves the task of
downsizing the request to the function and not its caller. It still
does so by halving the original request.
Approved by: kib (mentor)
Differential Revision: https://reviews.freebsd.org/D20228
i386 is the only architecture where uint64_t does not specify 8-bytes
alignment, which makes struct xswdev layout not compatible between
64bit and i386.
Reported and tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
o In vm_pager_bufferinit() create pbuf_zone and start accounting on how many
pbufs are we going to have set.
In various subsystems that are going to utilize pbufs create private zones
via call to pbuf_zsecond_create(). The latter calls uma_zsecond_create(),
and sets a limit on created zone. After startup preallocate pbufs according
to requirements of all pbuf zones.
Subsystems that used to have a private limit with old allocator now have
private pbuf zones: md(4), fusefs, NFS client, smbfs, VFS cluster, FFS,
swap, vnode pager.
The following subsystems use shared pbuf zone: cam(4), nvme(4), physio(9),
aio(4). They should have their private limits, but changing that is out of
scope of this commit.
o Fetch tunable value of kern.nswbuf from init_param2() and while here move
NSWBUF_MIN to opt_param.h and eliminate opt_swap.h, that was holding only
this option.
Default values aren't touched by this commit, but they probably should be
reviewed wrt to modern hardware.
This change removes a tight bottleneck from sendfile(2) operation, that
uses pbufs in vnode pager. Other pagers also would benefit from faster
allocation.
Together with: gallatin
Tested by: pho
If user configured the maxswapzone tunable, just take the literal
value for the initial zone sizing attempt. Before, it was only
possible to reduce the zone by the tunable.
While there, correct the message which was not correct when zone
creation rounded the size up.
Reported by: jmg
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D18381
This was introduced in r326329 and explains the crashes mentioned in
the commit log message for r339934. In particular, on INVARIANTS
kernels, UMA trashing causes the loop to exit early, leaving swap
blocks behind when they should have been freed. After r336984 this
became more problematic since new anonymous mappings were more
likely to reuse swapped-out subranges of existing VM objects, so faults
would trigger pageins of freed memory rather than returning zeroed
pages.
Reviewed by: kib
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17897
Change swap_reserve and swap_total to be in units of pages so that
swap reservations can be done using only atomics instead of using a single
global mutex for swap_reserve and a single mutex for all processes running
under the same uid for uid accounting.
Results in mmap speed up and a 70% increase in brk calls / second.
Reviewed by: alc@, markj@, kib@
Approved by: re (delphij@)
Differential Revision: https://reviews.freebsd.org/D16273
redundant, because uma_zone_reserve_kva() is performed on both zones and it
sets this same flag on the zone. (Moreover, the implementation of the swap
pager does not itself require these zones to be UMA_ZONE_NOFREE.)
Reviewed by: kib, markj
Approved by: re (gjb)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D17296
Before swp_pager_meta_build replaces an old swapblk with an new one,
it frees the old one. To allow such freeing of blocks to be
aggregated, have swp_pager_meta_build return the old swap block, and
make the caller responsible for freeing it.
Define a pair of short static functions, swp_pager_init_freerange and
swp_pager_update_freerange, to do the initialization and updating of
blk addresses and counters used in aggregating blocks to be freed.
Submitted by: Doug Moore <dougm@rice.edu>
Reviewed by: kib, markj (an earlier version)
Tested by: pho
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D13707
If fault started before vmspace_fork() locked the map, and then during
fork, vm_map_copy_entry()->vm_object_split() is executed, it is
possible that the fault instantiate the page into the original object
when the page was already copied into the new object (see
vm_map_split() for the orig/new objects terminology). This can happen
if split found a busy page (e.g. from the fault) and slept dropping
the objects lock, which allows the swap pager to instantiate
read-behind pages for the fault. Then the restart of the scan can see
a page in the scanned range, where it was already copied to the upper
object.
Fix it by instantiating the read-ahead pages before
swap_pager_getpages() method drops the lock to allocate pbuf. The
object scan would see the whole range prefilled with the busy pages
and not proceed the range.
Note that vm_fault rechecks the map generation count after the object
unlock, so that it restarts the handling if raced with split, and
re-lookups the right page from the upper object.
In collaboration with: alc
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.
Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c. A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.
Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.
Reviewed by: kib, cem, jhb, jtl
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14941
significant source of cache line contention from vm_page_alloc(). Use
accessors and vm_page_unwire_noq() so that the mechanism can be easily
changed in the future.
Reviewed by: markj
Discussed with: kib, glebius
Tested by: pho (earlier version)
Sponsored by: Netflix, Dell/EMC Isilon
Differential Revision: https://reviews.freebsd.org/D14273
global to per-domain state. Protect reservations with the free lock
from the domain that they belong to. Refactor to make vm domains more
of a first class object.
Reviewed by: markj, kib, gallatin
Tested by: pho
Sponsored by: Netflix, Dell/EMC Isilon
Differential Revision: https://reviews.freebsd.org/D14000
swp_pager_meta_ctl(), with no opportunity to recognize freeing of
consecutive blocks and free fewer block ranges. To open that opportunity,
this change removes the SWM_FREE option from swp_pager_meta_ctl(), and
compels the caller to do the freeing when a valid block address is returned.
In swap_pager_copy(), these frees are aggregated, so that a sequence of them
can be done at one time.
The only other caller to swp_pager_meta_ctl() that passed SWM_FREE,
swp_pager_unswapped(), is also modified to handle its single free
explicitly.
Submitted by: Doug Moore <dougm@rice.edu>
Reviewed by: kib (an earlier version)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D13290
blocks in a single call to blist_alloc(). However, when it frees
that space, it previously called blist_free() on each block, one at a
time. With this change, the swap pager identifies ranges of
contiguous blocks to be freed, and calls blist_free() once per
range. In one extreme case, that is described in the review, the time
to perform an munmap(2) was reduced by 55%.
Submitted by: Doug Moore <dougm@rice.edu>
Reviewed by: kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D12397
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.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
Initially, only tag files that use BSD 4-Clause "Original" license.
RelNotes: yes
Differential Revision: https://reviews.freebsd.org/D13133
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
one call to sysctl(2) from jemalloc startup code. (That also requires
changes to jemalloc, but I plan to push those to upstream first.)
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D12745
the page is already wired or queued. Prior to the elimination of PG_CACHED
pages, vm_page_grab() might have returned a valid, previously PG_CACHED
page, in which case enqueueing the page was necessary. Now, that can't
happen. Moreover, activating the page is a dubious choice, since the page
is not being accessed.
Reviewed by: kib
MFC after: 1 week
for analyzing the radix tree structures and reporting on the number, and
sizes, of maximal intervals of free blocks. The report includes the number
of maximal intervals, and also the number of them in each of several size
ranges, from small (size 1, or 3 to 4) to large (28657 to 46367) with size
boundaries defined by Fibonacci numbers. The report is written in the test
tool with the 's' command, or in a running kernel by sysctl.
The analysis of the radix tree frequently computes the position of the lone
bit set in a u_daddr_t, a computation that also appears in leaf allocation.
That computation has been moved into a function of its own, and optimized
for cases where an inlined machine instruction can replace the usual binary
search.
Submitted by: Doug Moore <dougm@rice.edu>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11906
In swp_pager_meta_build(), if the requested operation results in
freeing the last swap pointer in the swblk, free the trie node. Other
swap pager code does not expect to find completely empty swblk.
Reviewed by: alc, markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
swapblk for our index while we dropped the object lock.
Noted by: jeff
Reviewed by: alc, markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
The function return value is not used. Its argument is always
swap_total/PAGE_SIZE, so make it not take any arguments.
Submitted by: ota@j.email.ne.jp
PR: 221356
MFC after: 1 week
new use of the vm_object's lock to synchronize updates to a radix trie
mapping per-vm object page indices to on-disk swap blocks.
Fix a typo in a nearby comment.
Reviewed by: kib, markj
X-MFC with: r322913
Differential Revision: https://reviews.freebsd.org/D12134
blocks assigned to the object pages.
- The global swhash_mtx is removed, trie is synchronized by the
corresponding object lock.
- The swp_pager_meta_free_all() function used during object
termination is optimized by only looking at the trie instead of
having to search whole hash for the swap blocks owned by the object.
- On swap_pager_swapoff(), instead of iterating over the swhash,
global object list have to be inspected. There, we have to ensure
that we do see valid trie content if we see that the object type is
swap.
Sizing of the swblk zone is same as for swblock zone, each swblk maps
SWAP_META_PAGES pages.
Proposed by: alc
Reviewed by: alc, markj (previous version)
Tested by: alc, pho (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 month
Differential revision: https://reviews.freebsd.org/D11435
Decouple the pageout cluster size from the size of the hash table entry
used by the swap pager for mapping (object, pindex) to a block on the
swap device(s), and keep the size of a hash table entry at its current
size.
Eliminate a pointless macro.
Reviewed by: kib, markj (an earlier version)
MFC after: 4 weeks
Differential Revision: https://reviews.freebsd.org/D11305
dirty. Assert that they are fully dirty rather than redundantly calling
vm_page_dirty() on them.
Reviewed by: kib, markj
MFC after: 1 week
X-MFC after: r319932
beginning of a swap area for a disk label. However, neither r118390 nor
r118544, which increased the reservation from one to two blocks, correctly
accounted for these blocks when updating the variable "swap_pager_avail".
This change corrects that error.
Reviewed by: kib
MFC after: 5 days
pager used a different scheme for striping the allocation of swap space
across multiple devices. And, although blist_fill() was intended to support
fill operations with large counts, the old striping scheme never performed a
fill larger than the stripe size. Consequently, the misplacement of a
sanity check in blst_meta_fill() went undetected. Now, moving forward in
time to r118390, a new scheme for striping was introduced that maintained a
blist allocator per device, but as noted in r318995, swapoff_one() was not
fully and correctly converted to the new scheme. This change completes what
was started in r318995 by fixing the underlying bug in blst_meta_fill() that
stops swapoff_one() from simply performing a single blist_fill() operation.
Reviewed by: kib
MFC after: 5 days
Differential Revision: https://reviews.freebsd.org/D11043
short, half of the memory that is allocated to implement the radix tree is
wasted because we did not change "u_daddr_t" to be a 64-bit unsigned int
when we changed "daddr_t" to be a 64-bit (signed) int. (See r96849 and
r96851.)
Reviewed by: kib, markj
Tested by: pho
MFC after: 5 days
Differential Revision: https://reviews.freebsd.org/D11028
