30 May, 2011
1 commit
-
Inspired by an analysis from Hugh on why again all this doesn't explode
in our face.Signed-off-by: Peter Zijlstra
Signed-off-by: Linus Torvalds
29 May, 2011
6 commits
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On one machine I've been getting hangs, a page fault's anon_vma_prepare()
waiting in anon_vma_lock(), other processes waiting for that page's lock.This is a replay of last year's f18194275c39 "mm: fix hang on
anon_vma->root->lock".The new page_lock_anon_vma() places too much faith in its refcount: when
it has acquired the mutex_trylock(), it's possible that a racing task in
anon_vma_alloc() has just reallocated the struct anon_vma, set refcount
to 1, and is about to reset its anon_vma->root.Fix this by saving anon_vma->root, and relying on the usual page_mapped()
check instead of a refcount check: if page is still mapped, the anon_vma
is still ours; if page is not still mapped, we're no longer interested.Signed-off-by: Hugh Dickins
Signed-off-by: Linus Torvalds -
I've hit the "address >= vma->vm_end" check in do_page_add_anon_rmap()
just once. The stack showed khugepaged allocation trying to compact
pages: the call to page_add_anon_rmap() coming from remove_migration_pte().That path holds anon_vma lock, but does not hold mmap_sem: it can
therefore race with a split_vma(), and in commit 5f70b962ccc2 "mmap:
avoid unnecessary anon_vma lock" we just took away the anon_vma lock
protection when adjusting vma->vm_end.I don't think that particular BUG_ON ever caught anything interesting,
so better replace it by a comment, than reinstate the anon_vma locking.Signed-off-by: Hugh Dickins
Signed-off-by: Linus Torvalds -
While running fsx on tmpfs with a memhog then swapoff, swapoff was hanging
(interruptibly), repeatedly failing to locate the owner of a 0xff entry in
the swap_map.Although shmem_writepage() does abandon when it sees incoming page index
is beyond eof, there was still a window in which shmem_truncate_range()
could come in between writepage's dropping lock and updating swap_map,
find the half-completed swap_map entry, and in trying to free it,
leave it in a state that swap_shmem_alloc() could not correct.Arguably a bug in __swap_duplicate()'s and swap_entry_free()'s handling
of the different cases, but easiest to fix by moving swap_shmem_alloc()
under cover of the lock.More interesting than the bug: it's been there since 2.6.33, why could
I not see it with earlier kernels? The mmotm of two weeks ago seems to
have some magic for generating races, this is just one of three I found.With yesterday's git I first saw this in mainline, bisected in search of
that magic, but the easy reproducibility evaporated. Oh well, fix the bug.Signed-off-by: Hugh Dickins
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (36 commits)
Cache xattr security drop check for write v2
fs: block_page_mkwrite should wait for writeback to finish
mm: Wait for writeback when grabbing pages to begin a write
configfs: remove unnecessary dentry_unhash on rmdir, dir rename
fat: remove unnecessary dentry_unhash on rmdir, dir rename
hpfs: remove unnecessary dentry_unhash on rmdir, dir rename
minix: remove unnecessary dentry_unhash on rmdir, dir rename
fuse: remove unnecessary dentry_unhash on rmdir, dir rename
coda: remove unnecessary dentry_unhash on rmdir, dir rename
afs: remove unnecessary dentry_unhash on rmdir, dir rename
affs: remove unnecessary dentry_unhash on rmdir, dir rename
9p: remove unnecessary dentry_unhash on rmdir, dir rename
ncpfs: fix rename over directory with dangling references
ncpfs: document dentry_unhash usage
ecryptfs: remove unnecessary dentry_unhash on rmdir, dir rename
hostfs: remove unnecessary dentry_unhash on rmdir, dir rename
hfsplus: remove unnecessary dentry_unhash on rmdir, dir rename
hfs: remove unnecessary dentry_unhash on rmdir, dir rename
omfs: remove unnecessary dentry_unhash on rmdir, dir rneame
udf: remove unnecessary dentry_unhash from rmdir, dir rename
... -
…l/git/tip/linux-2.6-tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (25 commits)
perf: Fix SIGIO handling
perf top: Don't stop if no kernel symtab is found
perf top: Handle kptr_restrict
perf top: Remove unused macro
perf events: initialize fd array to -1 instead of 0
perf tools: Make sure kptr_restrict warnings fit 80 col terms
perf tools: Fix build on older systems
perf symbols: Handle /proc/sys/kernel/kptr_restrict
perf: Remove duplicate headers
ftrace: Add internal recursive checks
tracing: Update btrfs's tracepoints to use u64 interface
tracing: Add __print_symbolic_u64 to avoid warnings on 32bit machine
ftrace: Set ops->flag to enabled even on static function tracing
tracing: Have event with function tracer check error return
ftrace: Have ftrace_startup() return failure code
jump_label: Check entries limit in __jump_label_update
ftrace/recordmcount: Avoid STT_FUNC symbols as base on ARM
scripts/tags.sh: Add magic for trace-events for etags too
scripts/tags.sh: Fix ctags for DEFINE_EVENT()
x86/ftrace: Fix compiler warning in ftrace.c
... -
Some recent benchmarking on btrfs showed that a major scaling bottleneck
on large systems on btrfs is currently the xattr lookup on every write.Why xattr lookup on every write I hear you ask?
write wants to drop suid and security related xattrs that could set o
capabilities for executables. To do that it currently looks up
security.capability on EVERY write (even for non executables) to decide
whether to drop it or not.In btrfs this causes an additional tree walk, hitting some per file system
locks and quite bad scalability. In a simple read workload on a 8S
system I saw over 90% CPU time in spinlocks related to that.Chris Mason tells me this is also a problem in ext4, where it hits
the global mbcache lock.This patch adds a simple per inode to avoid this problem. We only
do the lookup once per file and then if there is no xattr cache
the decision. All xattr changes clear the flag.I also used the same flag to avoid the suid check, although
that one is pretty cheap.A file system can also set this flag when it creates the inode,
if it has a cheap way to do so. This is done for some common file systems
in followon patches.With this patch a major part of the lock contention disappears
for btrfs. Some testing on smaller systems didn't show significant
performance changes, but at least it helps the larger systems
and is generally more efficient.v2: Rename is_sgid. add file system helper.
Cc: chris.mason@oracle.com
Cc: josef@redhat.com
Cc: viro@zeniv.linux.org.uk
Cc: agruen@linbit.com
Cc: Serge E. Hallyn
Signed-off-by: Andi Kleen
Signed-off-by: Al Viro
28 May, 2011
1 commit
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When grabbing a page for a buffered IO write, the mm should wait for writeback
on the page to complete so that the page does not become writable during the IO
operation. This change is needed to provide page stability during writes for
all filesystems.Signed-off-by: Darrick J. Wong
Signed-off-by: Al Viro
27 May, 2011
19 commits
-
…rostedt/linux-2.6-trace into perf/urgent
-
…x/kernel/git/jeremy/xen
* 'upstream/tidy-xen-mmu-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: fix compile without CONFIG_XEN_DEBUG_FS
Use arbitrary_virt_to_machine() to deal with ioremapped pud updates.
Use arbitrary_virt_to_machine() to deal with ioremapped pmd updates.
xen/mmu: remove all ad-hoc stats stuff
xen: use normal virt_to_machine for ptes
xen: make a pile of mmu pvop functions static
vmalloc: remove vmalloc_sync_all() from alloc_vm_area()
xen: condense everything onto xen_set_pte
xen: use mmu_update for xen_set_pte_at()
xen: drop all the special iomap pte paths. -
Two new stats in per-memcg memory.stat which tracks the number of page
faults and number of major page faults."pgfault"
"pgmajfault"They are different from "pgpgin"/"pgpgout" stat which count number of
pages charged/discharged to the cgroup and have no meaning of reading/
writing page to disk.It is valuable to track the two stats for both measuring application's
performance as well as the efficiency of the kernel page reclaim path.
Counting pagefaults per process is useful, but we also need the aggregated
value since processes are monitored and controlled in cgroup basis in
memcg.Functional test: check the total number of pgfault/pgmajfault of all
memcgs and compare with global vmstat value:$ cat /proc/vmstat | grep fault
pgfault 1070751
pgmajfault 553$ cat /dev/cgroup/memory.stat | grep fault
pgfault 1071138
pgmajfault 553
total_pgfault 1071142
total_pgmajfault 553$ cat /dev/cgroup/A/memory.stat | grep fault
pgfault 199
pgmajfault 0
total_pgfault 199
total_pgmajfault 0Performance test: run page fault test(pft) wit 16 thread on faulting in
15G anon pages in 16G container. There is no regression noticed on the
"flt/cpu/s"Sample output from pft:
TAG pft:anon-sys-default:
Gb Thr CLine User System Wall flt/cpu/s fault/wsec
15 16 1 0.67s 233.41s 14.76s 16798.546 266356.260+-------------------------------------------------------------------------+
N Min Max Median Avg Stddev
x 10 16682.962 17344.027 16913.524 16928.812 166.5362
+ 10 16695.568 16923.896 16820.604 16824.652 84.816568
No difference proven at 95.0% confidence[akpm@linux-foundation.org: fix build]
[hughd@google.com: shmem fix]
Signed-off-by: Ying Han
Acked-by: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Reviewed-by: Minchan Kim
Cc: Daisuke Nishimura
Acked-by: Balbir Singh
Signed-off-by: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The new API exports numa_maps per-memcg basis. This is a piece of useful
information where it exports per-memcg page distribution across real numa
nodes.One of the usecases is evaluating application performance by combining
this information w/ the cpu allocation to the application.The output of the memory.numastat tries to follow w/ simiar format of
numa_maps like:total= N0= N1= ...
file= N0= N1= ...
anon= N0= N1= ...
unevictable= N0= N1= ...And we have per-node:
total = file + anon + unevictable
$ cat /dev/cgroup/memory/memory.numa_stat
total=250020 N0=87620 N1=52367 N2=45298 N3=64735
file=225232 N0=83402 N1=46160 N2=40522 N3=55148
anon=21053 N0=3424 N1=6207 N2=4776 N3=6646
unevictable=3735 N0=794 N1=0 N2=0 N3=2941Signed-off-by: Ying Han
Cc: Balbir Singh
Cc: Daisuke Nishimura
Acked-by: KAMEZAWA Hiroyuki
Acked-by: Daisuke Nishimura
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The caller of the function has been renamed to zone_nr_lru_pages(), and
this is just fixing up in the memcg code. The current name is easily to
be mis-read as zone's total number of pages.Signed-off-by: Ying Han
Acked-by: Johannes Weiner
Acked-by: KAMEZAWA Hiroyuki
Reviewed-by: Minchan Kim
Cc: Balbir Singh
Cc: Daisuke Nishimura
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If the memcg reclaim code detects the target memcg below its limit it
exits and returns a guaranteed non-zero value so that the charge is
retried.Nowadays, the charge side checks the memcg limit itself and does not rely
on this non-zero return value trick.This patch removes it. The reclaim code will now always return the true
number of pages it reclaimed on its own.Signed-off-by: Johannes Weiner
Acked-by: Rik van Riel
Acked-by: Ying Han
Acked-by: KAMEZAWA Hiroyuki
Reviewed-by: Michal Hocko
Cc: Balbir Singh
Cc: KOSAKI Motohiro
Cc: Mel Gorman
Cc: Daisuke Nishimura
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
During memory reclaim we determine the number of pages to be scanned per
zone as(anon + file) >> priority.
Assume
scan = (anon + file) >> priority.If scan < SWAP_CLUSTER_MAX, the scan will be skipped for this time and
priority gets higher. This has some problems.1. This increases priority as 1 without any scan.
To do scan in this priority, amount of pages should be larger than 512M.
If pages>>priority < SWAP_CLUSTER_MAX, it's recorded and scan will be
batched, later. (But we lose 1 priority.)
If memory size is below 16M, pages >> priority is 0 and no scan in
DEF_PRIORITY forever.2. If zone->all_unreclaimabe==true, it's scanned only when priority==0.
So, x86's ZONE_DMA will never be recoverred until the user of pages
frees memory by itself.3. With memcg, the limit of memory can be small. When using small memcg,
it gets priority < DEF_PRIORITY-2 very easily and need to call
wait_iff_congested().
For doing scan before priorty=9, 64MB of memory should be used.Then, this patch tries to scan SWAP_CLUSTER_MAX of pages in force...when
1. the target is enough small.
2. it's kswapd or memcg reclaim.Then we can avoid rapid priority drop and may be able to recover
all_unreclaimable in a small zones. And this patch removes nr_saved_scan.
This will allow scanning in this priority even when pages >> priority is
very small.Signed-off-by: KAMEZAWA Hiroyuki
Acked-by: Ying Han
Cc: Balbir Singh
Cc: KOSAKI Motohiro
Cc: Daisuke Nishimura
Cc: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Presently, memory cgroup's direct reclaim frees memory from the current
node. But this has some troubles. Usually when a set of threads works in
a cooperative way, they tend to operate on the same node. So if they hit
limits under memcg they will reclaim memory from themselves, damaging the
active working set.For example, assume 2 node system which has Node 0 and Node 1 and a memcg
which has 1G limit. After some work, file cache remains and the usages
areNode 0: 1M
Node 1: 998M.and run an application on Node 0, it will eat its foot before freeing
unnecessary file caches.This patch adds round-robin for NUMA and adds equal pressure to each node.
When using cpuset's spread memory feature, this will work very well.But yes, a better algorithm is needed.
[akpm@linux-foundation.org: comment editing]
[kamezawa.hiroyu@jp.fujitsu.com: fix time comparisons]
Signed-off-by: Ying Han
Signed-off-by: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Cc: KOSAKI Motohiro
Cc: Daisuke Nishimura
Cc: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Move page-freeing code out of swap_cgroup_mutex in the hope that it could
reduce few of theoretical contentions between swapons and/or swapoffs.This is just a cleanup, no functional changes.
Signed-off-by: Namhyung Kim
Acked-by: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
It allocated one more page than necessary if @max_pages was a multiple of
SC_PER_PAGE.Signed-off-by: Namhyung Kim
Acked-by: KAMEZAWA Hiroyuki
Acked-by: Balbir Singh
Cc: Daisuke Nishimura
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit ca371c0d7e23 ("memcg: fix page_cgroup fatal error in FLATMEM")
removes call to alloc_bootmem() in the function so that it can be marked
as __meminit to reduce memory usage when MEMORY_HOTPLUG=n.Also as the new helper function alloc_page_cgroup() is called only in the
function, it should be marked too.Signed-off-by: Namhyung Kim
Acked-by: KAMEZAWA Hiroyuki
Acked-by: Balbir Singh
Cc: Michal Hocko
Cc: Daisuke Nishimura
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
next_mz is assigned to NULL if __mem_cgroup_largest_soft_limit_node
selects the same mz. This doesn't make much sense as we assign to the
variable right in the next loop.Compiler will probably optimize this out but it is little bit confusing
for the code reading.Signed-off-by: Michal Hocko
Acked-by: Daisuke Nishimura
Cc: Balbir Singh
Cc: KAMEZAWA Hiroyuki
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
We recently added the change in global background reclaim which counts the
return value of soft_limit reclaim. Now this patch adds the similar logic
on global direct reclaim.We should skip scanning global LRU on shrink_zone if soft_limit reclaim
does enough work. This is the first step where we start with counting the
nr_scanned and nr_reclaimed from soft_limit reclaim into global
scan_control.Signed-off-by: Ying Han
Cc: KOSAKI Motohiro
Cc: Minchan Kim
Cc: Daisuke Nishimura
Cc: Balbir Singh
Cc: KAMEZAWA Hiroyuki
Cc: Mel Gorman
Cc: Johannes Weiner
Cc: Rik van Riel
Cc: Hugh Dickins
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The global kswapd scans per-zone LRU and reclaims pages regardless of the
cgroup. It breaks memory isolation since one cgroup can end up reclaiming
pages from another cgroup. Instead we should rely on memcg-aware target
reclaim including per-memcg kswapd and soft_limit hierarchical reclaim under
memory pressure.In the global background reclaim, we do soft reclaim before scanning the
per-zone LRU. However, the return value is ignored. This patch is the first
step to skip shrink_zone() if soft_limit reclaim does enough work.This is part of the effort which tries to reduce reclaiming pages in global
LRU in memcg. The per-memcg background reclaim patchset further enhances the
per-cgroup targetting reclaim, which I should have V4 posted shortly.Try running multiple memory intensive workloads within seperate memcgs. Watch
the counters of soft_steal in memory.stat.$ cat /dev/cgroup/A/memory.stat | grep 'soft'
soft_steal 240000
soft_scan 240000
total_soft_steal 240000
total_soft_scan 240000This patch:
In the global background reclaim, we do soft reclaim before scanning the
per-zone LRU. However, the return value is ignored.We would like to skip shrink_zone() if soft_limit reclaim does enough
work. Also, we need to make the memory pressure balanced across per-memcg
zones, like the logic vm-core. This patch is the first step where we
start with counting the nr_scanned and nr_reclaimed from soft_limit
reclaim into the global scan_control.Signed-off-by: Ying Han
Cc: KOSAKI Motohiro
Cc: Minchan Kim
Cc: Rik van Riel
Cc: Mel Gorman
Cc: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Acked-by: Daisuke Nishimura
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add cgroup subsystem callbacks for per-thread attachment in atomic contexts
Add can_attach_task(), pre_attach(), and attach_task() as new callbacks
for cgroups's subsystem interface. Unlike can_attach and attach, these
are for per-thread operations, to be called potentially many times when
attaching an entire threadgroup.Also, the old "bool threadgroup" interface is removed, as replaced by
this. All subsystems are modified for the new interface - of note is
cpuset, which requires from/to nodemasks for attach to be globally scoped
(though per-cpuset would work too) to persist from its pre_attach to
attach_task and attach.This is a pre-patch for cgroup-procs-writable.patch.
Signed-off-by: Ben Blum
Cc: "Eric W. Biederman"
Cc: Li Zefan
Cc: Matt Helsley
Reviewed-by: Paul Menage
Cc: Oleg Nesterov
Cc: David Rientjes
Cc: Miao Xie
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem:
xen: cleancache shim to Xen Transcendent Memory
ocfs2: add cleancache support
ext4: add cleancache support
btrfs: add cleancache support
ext3: add cleancache support
mm/fs: add hooks to support cleancache
mm: cleancache core ops functions and config
fs: add field to superblock to support cleancache
mm/fs: cleancache documentationFix up trivial conflict in fs/btrfs/extent_io.c due to includes
-
The type of vma->vm_flags is 'unsigned long'. Neither 'int' nor
'unsigned int'. This patch fixes such misuse.Signed-off-by: KOSAKI Motohiro
[ Changed to use a typedef - we'll extend it to cover more cases
later, since there has been discussion about making it a 64-bit
type.. - Linus ]
Signed-off-by: Linus Torvalds -
This fourth patch of eight in this cleancache series provides the
core hooks in VFS for: initializing cleancache per filesystem;
capturing clean pages reclaimed by page cache; attempting to get
pages from cleancache before filesystem read; and ensuring coherency
between pagecache, disk, and cleancache. Note that the placement
of these hooks was stable from 2.6.18 to 2.6.38; a minor semantic
change was required due to a patchset in 2.6.39.All hooks become no-ops if CONFIG_CLEANCACHE is unset, or become
a check of a boolean global if CONFIG_CLEANCACHE is set but no
cleancache "backend" has claimed cleancache_ops.Details and a FAQ can be found in Documentation/vm/cleancache.txt
[v8: minchan.kim@gmail.com: adapt to new remove_from_page_cache function]
Signed-off-by: Chris Mason
Signed-off-by: Dan Magenheimer
Reviewed-by: Jeremy Fitzhardinge
Reviewed-by: Konrad Rzeszutek Wilk
Cc: Andrew Morton
Cc: Al Viro
Cc: Matthew Wilcox
Cc: Nick Piggin
Cc: Mel Gorman
Cc: Rik Van Riel
Cc: Jan Beulich
Cc: Andreas Dilger
Cc: Ted Ts'o
Cc: Mark Fasheh
Cc: Joel Becker
Cc: Nitin Gupta -
This third patch of eight in this cleancache series provides
the core code for cleancache that interfaces between the hooks in
VFS and individual filesystems and a cleancache backend. It also
includes build and config patches.Two new files are added: mm/cleancache.c and include/linux/cleancache.h.
Note that CONFIG_CLEANCACHE can default to on; in systems that do
not provide a cleancache backend, all hooks devolve to a simple
check of a global enable flag, so performance impact should
be negligible but can be reduced to zero impact if config'ed off.
However for this first commit, it defaults to off.Details and a FAQ can be found in Documentation/vm/cleancache.txt
Credits: Cleancache_ops design derived from Jeremy Fitzhardinge
design for tmem[v8: dan.magenheimer@oracle.com: fix exportfs call affecting btrfs]
[v8: akpm@linux-foundation.org: use static inline function, not macro]
[v7: dan.magenheimer@oracle.com: cleanup sysfs and remove cleancache prefix]
[v6: JBeulich@novell.com: robustly handle buggy fs encode_fh actor definition]
[v5: jeremy@goop.org: clean up global usage and static var names]
[v5: jeremy@goop.org: simplify init hook and any future fs init changes]
[v5: hch@infradead.org: cleaner non-global interface for ops registration]
[v4: adilger@sun.com: interface must support exportfs FS's]
[v4: hch@infradead.org: interface must support 64-bit FS on 32-bit kernel]
[v3: akpm@linux-foundation.org: use one ops struct to avoid pointer hops]
[v3: akpm@linux-foundation.org: document and ensure PageLocked reqts are met]
[v3: ngupta@vflare.org: fix success/fail codes, change funcs to void]
[v2: viro@ZenIV.linux.org.uk: use sane types]
Signed-off-by: Dan Magenheimer
Reviewed-by: Jeremy Fitzhardinge
Reviewed-by: Konrad Rzeszutek Wilk
Acked-by: Al Viro
Acked-by: Andrew Morton
Acked-by: Nitin Gupta
Acked-by: Minchan Kim
Acked-by: Andreas Dilger
Acked-by: Jan Beulich
Cc: Matthew Wilcox
Cc: Nick Piggin
Cc: Mel Gorman
Cc: Rik Van Riel
Cc: Chris Mason
Cc: Ted Ts'o
Cc: Mark Fasheh
Cc: Joel Becker
26 May, 2011
3 commits
-
Commit a71ae47a2cbf ("slub: Fix double bit unlock in debug mode")
removed the only goto to this label, resulting inmm/slub.c: In function '__slab_alloc':
mm/slub.c:1834: warning: label 'unlock_out' defined but not usedfixed trivially by the removal of the label itself too.
Reported-by: Stephen Rothwell
Cc: Christoph Lameter
Signed-off-by: Linus Torvalds -
The functions probe_kernel_write() and probe_kernel_read() do not modify
the src pointer. Allow const pointers to be passed in without the need
of a typecast.Acked-by: Mike Frysinger
Acked-by: Heiko Carstens
Acked-by: Martin Schwidefsky
Signed-off-by: Steven Rostedt
Link: http://lkml.kernel.org/r/1305824936.1465.4.camel@gandalf.stny.rr.com -
* 'for-2.6.40/core' of git://git.kernel.dk/linux-2.6-block: (40 commits)
cfq-iosched: free cic_index if cfqd allocation fails
cfq-iosched: remove unused 'group_changed' in cfq_service_tree_add()
cfq-iosched: reduce bit operations in cfq_choose_req()
cfq-iosched: algebraic simplification in cfq_prio_to_maxrq()
blk-cgroup: Initialize ioc->cgroup_changed at ioc creation time
block: move bd_set_size() above rescan_partitions() in __blkdev_get()
block: call elv_bio_merged() when merged
cfq-iosched: Make IO merge related stats per cpu
cfq-iosched: Fix a memory leak of per cpu stats for root group
backing-dev: Kill set but not used var in bdi_debug_stats_show()
block: get rid of on-stack plugging debug checks
blk-throttle: Make no throttling rule group processing lockless
blk-cgroup: Make cgroup stat reset path blkg->lock free for dispatch stats
blk-cgroup: Make 64bit per cpu stats safe on 32bit arch
blk-throttle: Make dispatch stats per cpu
blk-throttle: Free up a group only after one rcu grace period
blk-throttle: Use helper function to add root throtl group to lists
blk-throttle: Introduce a helper function to fill in device details
blk-throttle: Dynamically allocate root group
blk-cgroup: Allow sleeping while dynamically allocating a group
...
25 May, 2011
10 commits
-
Currently on nommu arch mmap(),mremap() and munmap() doesn't do
page_align() which isn't consist with mmu arch and cause some issues.First, some drivers' mmap() function depends on vma->vm_end - vma->start
is page aligned which is true on mmu arch but not on nommu. eg: uvc
camera driver.Second munmap() may return -EINVAL[split file] error in cases when end is
not page aligned(passed into from userspace) but vma->vm_end is aligned
dure to split or driver's mmap() ops.Add page alignment to fix those issues.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Bob Liu
Cc: David Howells
Cc: Paul Mundt
Cc: Greg Ungerer
Cc: Geert Uytterhoeven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The zone->lru_lock is heavily contented in workload where activate_page()
is frequently used. We could do batch activate_page() to reduce the lock
contention. The batched pages will be added into zone list when the pool
is full or page reclaim is trying to drain them.For example, in a 4 socket 64 CPU system, create a sparse file and 64
processes, processes shared map to the file. Each process read access the
whole file and then exit. The process exit will do unmap_vmas() and cause
a lot of activate_page() call. In such workload, we saw about 58% total
time reduction with below patch. Other workloads with a lot of
activate_page also benefits a lot too.Andrew Morton suggested activate_page() and putback_lru_pages() should
follow the same path to active pages, but this is hard to implement (see
commit 7a608572a282a ("Revert "mm: batch activate_page() to reduce lock
contention")). On the other hand, do we really need putback_lru_pages()
to follow the same path? I tested several FIO/FFSB benchmark (about 20
scripts for each benchmark) in 3 machines here from 2 sockets to 4
sockets. My test doesn't show anything significant with/without below
patch (there is slight difference but mostly some noise which we found
even without below patch before). Below patch basically returns to the
same as my first post.I tested some microbenchmarks:
case-anon-cow-rand-mt 0.58%
case-anon-cow-rand -3.30%
case-anon-cow-seq-mt -0.51%
case-anon-cow-seq -5.68%
case-anon-r-rand-mt 0.23%
case-anon-r-rand 0.81%
case-anon-r-seq-mt -0.71%
case-anon-r-seq -1.99%
case-anon-rx-rand-mt 2.11%
case-anon-rx-seq-mt 3.46%
case-anon-w-rand-mt -0.03%
case-anon-w-rand -0.50%
case-anon-w-seq-mt -1.08%
case-anon-w-seq -0.12%
case-anon-wx-rand-mt -5.02%
case-anon-wx-seq-mt -1.43%
case-fork 1.65%
case-fork-sleep -0.07%
case-fork-withmem 1.39%
case-hugetlb -0.59%
case-lru-file-mmap-read-mt -0.54%
case-lru-file-mmap-read 0.61%
case-lru-file-mmap-read-rand -2.24%
case-lru-file-readonce -0.64%
case-lru-file-readtwice -11.69%
case-lru-memcg -1.35%
case-mmap-pread-rand-mt 1.88%
case-mmap-pread-rand -15.26%
case-mmap-pread-seq-mt 0.89%
case-mmap-pread-seq -69.72%
case-mmap-xread-rand-mt 0.71%
case-mmap-xread-seq-mt 0.38%The most significent are:
case-lru-file-readtwice -11.69%
case-mmap-pread-rand -15.26%
case-mmap-pread-seq -69.72%which use activate_page a lot. others are basically variations because
each run has slightly difference.In UP case, 'size mm/swap.o'
before the two patches:
text data bss dec hex filename
6466 896 4 7366 1cc6 mm/swap.o
after the two patches:
text data bss dec hex filename
6343 896 4 7243 1c4b mm/swap.oSigned-off-by: Shaohua Li
Cc: KOSAKI Motohiro
Cc: Hiroyuki Kamezawa
Cc: Andi Kleen
Cc: Minchan Kim
Cc: Rik van Riel
Cc: Mel Gorman
Cc: Johannes Weiner
Cc: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
I believe I found a problem in __alloc_pages_slowpath, which allows a
process to get stuck endlessly looping, even when lots of memory is
available.Running an I/O and memory intensive stress-test I see a 0-order page
allocation with __GFP_IO and __GFP_WAIT, running on a system with very
little free memory. Right about the same time that the stress-test gets
killed by the OOM-killer, the utility trying to allocate memory gets stuck
in __alloc_pages_slowpath even though most of the systems memory was freed
by the oom-kill of the stress-test.The utility ends up looping from the rebalance label down through the
wait_iff_congested continiously. Because order=0,
__alloc_pages_direct_compact skips the call to get_page_from_freelist.
Because all of the reclaimable memory on the system has already been
reclaimed, __alloc_pages_direct_reclaim skips the call to
get_page_from_freelist. Since there is no __GFP_FS flag, the block with
__alloc_pages_may_oom is skipped. The loop hits the wait_iff_congested,
then jumps back to rebalance without ever trying to
get_page_from_freelist. This loop repeats infinitely.The test case is pretty pathological. Running a mix of I/O stress-tests
that do a lot of fork() and consume all of the system memory, I can pretty
reliably hit this on 600 nodes, in about 12 hours. 32GB/node.Signed-off-by: Andrew Barry
Signed-off-by: Minchan Kim
Reviewed-by: Rik van Riel
Acked-by: Mel Gorman
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The noswapaccount parameter has been deprecated since 2.6.38 without any
complaints from users so we can remove it. swapaccount=0|1 can be used
instead.As we are removing the parameter we can also clean up swapaccount because
it doesn't have to accept an empty string anymore (to match noswapaccount)
and so we can push = into __setup macro rather than checking "=1" resp.
"=0" stringsSigned-off-by: Michal Hocko
Cc: Hiroyuki Kamezawa
Cc: Daisuke Nishimura
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Moving show_numa_map() from mempolicy.c to task_mmu.c solves several
issues.- Having the show() operation "miles away" from the corresponding
seq_file iteration operations is a maintenance burden.- The need to export ad hoc info like struct proc_maps_private is
eliminated.- The implementation of show_numa_map() can be improved in a simple
manner by cooperating with the other seq_file operations (start,
stop, etc) -- something that would be messy to do without this
change.Signed-off-by: Stephen Wilson
Reviewed-by: KOSAKI Motohiro
Cc: Hugh Dickins
Cc: David Rientjes
Cc: Lee Schermerhorn
Cc: Alexey Dobriyan
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This function has been superseded by gather_hugetbl_stats() and is no
longer needed.Signed-off-by: Stephen Wilson
Reviewed-by: KOSAKI Motohiro
Cc: Hugh Dickins
Cc: David Rientjes
Cc: Lee Schermerhorn
Cc: Alexey Dobriyan
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Improve the prototype of gather_stats() to take a struct numa_maps as
argument instead of a generic void *. Update all callers to make the
required type explicit.Since gather_stats() is not needed before its definition and is scheduled
to be moved out of mempolicy.c the declaration is removed as well.Signed-off-by: Stephen Wilson
Reviewed-by: KOSAKI Motohiro
Cc: Hugh Dickins
Cc: David Rientjes
Cc: Lee Schermerhorn
Cc: Alexey Dobriyan
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Mapping statistics in a NUMA environment is now computed using the generic
walk_page_range() logic. Remove the old/equivalent functionality.Signed-off-by: Stephen Wilson
Reviewed-by: KOSAKI Motohiro
Cc: Hugh Dickins
Cc: David Rientjes
Cc: Lee Schermerhorn
Cc: Alexey Dobriyan
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Converting show_numa_map() to use the generic routine decouples the
function from mempolicy.c, allowing it to be moved out of the mm subsystem
and into fs/proc.Also, include KSM pages in /proc/pid/numa_maps statistics. The pagewalk
logic implemented by check_pte_range() failed to account for such pages as
they were not applicable to the page migration case.Signed-off-by: Stephen Wilson
Reviewed-by: KOSAKI Motohiro
Cc: Hugh Dickins
Cc: David Rientjes
Cc: Lee Schermerhorn
Cc: Alexey Dobriyan
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In commit 48fce3429d ("mempolicies: unexport get_vma_policy()")
get_vma_policy() was marked static as all clients were local to
mempolicy.c.However, the decision to generate /proc/pid/numa_maps in the numa memory
policy code and outside the procfs subsystem introduces an artificial
interdependency between the two systems. Exporting get_vma_policy() once
again is the first step to clean up this interdependency.Signed-off-by: Stephen Wilson
Reviewed-by: KOSAKI Motohiro
Cc: Hugh Dickins
Cc: David Rientjes
Cc: Lee Schermerhorn
Cc: Alexey Dobriyan
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
