Now, page-stat-per-memcg is recorded into per page_cgroup flag by
duplicating page's status into the flag. The reason is that memcg has a
feature to move a page from a group to another group and we have race
between "move" and "page stat accounting",
Under current logic, assume CPU-A and CPU-B. CPU-A does "move" and CPU-B
does "page stat accounting".
When CPU-A goes 1st,
CPU-A CPU-B
update "struct page" info.
move_lock_mem_cgroup(memcg)
see pc->flags
copy page stat to new group
overwrite pc->mem_cgroup.
move_unlock_mem_cgroup(memcg)
move_lock_mem_cgroup(mem)
set pc->flags
update page stat accounting
move_unlock_mem_cgroup(mem)
stat accounting is guarded by move_lock_mem_cgroup() and "move" logic
(CPU-A) doesn't see changes in "struct page" information.
But it's costly to have the same information both in 'struct page' and
'struct page_cgroup'. And, there is a potential problem.
For example, assume we have PG_dirty accounting in memcg.
PG_..is a flag for struct page.
PCG_ is a flag for struct page_cgroup.
(This is just an example. The same problem can be found in any
kind of page stat accounting.)
CPU-A CPU-B
TestSet PG_dirty
(delay) TestClear PG_dirty
if (TestClear(PCG_dirty))
memcg->nr_dirty--
if (TestSet(PCG_dirty))
memcg->nr_dirty++
Here, memcg->nr_dirty = +1, this is wrong. This race was reported by Greg
Thelen <gthelen@google.com>. Now, only FILE_MAPPED is supported but
fortunately, it's serialized by page table lock and this is not real bug,
_now_,
If this potential problem is caused by having duplicated information in
struct page and struct page_cgroup, we may be able to fix this by using
original 'struct page' information. But we'll have a problem in "move
account"
accounting information may be double-counted. This was original reason to
have PCG_xxx flags but it seems PCG_xxx has another problem.
I think we need a bigger lock as
move_lock_mem_cgroup(page)
TestSetPageDirty(page)
update page stats (without any checks)
move_unlock_mem_cgroup(page)
This fixes both of problems and we don't have to duplicate page flag into
page_cgroup. Please note: move_lock_mem_cgroup() is held only when there
are possibility of "account move" under the system. So, in most path,
status update will go without atomic locks.
This patch introduces mem_cgroup_begin_update_page_stat() and
mem_cgroup_end_update_page_stat() both should be called at modifying
'struct page' information if memcg takes care of it. as
mem_cgroup_begin_update_page_stat()
modify page information
mem_cgroup_update_page_stat()
=> never check any 'struct page' info, just update counters.
mem_cgroup_end_update_page_stat().
This patch is slow because we need to call begin_update_page_stat()/
end_update_page_stat() regardless of accounted will be changed or not. A
following patch adds an easy optimization and reduces the cost.
[akpm@linux-foundation.org: s/lock/locked/]
[hughd@google.com: fix deadlock by avoiding stat lock when anon] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Greg Thelen <gthelen@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Ying Han <yinghan@google.com> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PCG_MOVE_LOCK is used for bit spinlock to avoid race between overwriting
pc->mem_cgroup and page statistics accounting per memcg. This lock helps
to avoid the race but the race is very rare because moving tasks between
cgroup is not a usual job. So, it seems using 1bit per page is too
costly.
This patch changes this lock as per-memcg spinlock and removes
PCG_MOVE_LOCK.
If smaller lock is required, we'll be able to add some hashes but I'd like
to start from this.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Ying Han <yinghan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We record 'the page is cache' with the PCG_CACHE bit in page_cgroup.
Here, "CACHE" means anonymous user pages (and SwapCache). This doesn't
include shmem.
Considering callers, at charge/uncharge, the caller should know what the
page is and we don't need to record it by using one bit per page.
This patch removes PCG_CACHE bit and make callers of
mem_cgroup_charge_statistics() to specify what the page is.
About page migration: Mapping of the used page is not touched during migra
tion (see page_remove_rmap) so we can rely on it and push the correct
charge type down to __mem_cgroup_uncharge_common from end_migration for
unused page. The force flag was misleading was abused for skipping the
needless page_mapped() / PageCgroupMigration() check, as we know the
unused page is no longer mapped and cleared the migration flag just a few
lines up. But doing the checks is no biggie and it's not worth adding
another flag just to skip them.
[akpm@linux-foundation.org: checkpatch fixes]
[hughd@google.com: fix PageAnon uncharging] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Hugh Dickins <hughd@google.com> Cc: Ying Han <yinghan@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 21 Mar 2012 23:34:21 +0000 (16:34 -0700)]
memcg: let css_get_next() rely upon rcu_read_lock()
Remove lock and unlock around css_get_next()'s call to idr_get_next().
memcg iterators (only users of css_get_next) already did rcu_read_lock(),
and its comment demands that; but add a WARN_ON_ONCE to make sure of it.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 21 Mar 2012 23:34:21 +0000 (16:34 -0700)]
cgroup: revert ss_id_lock to spinlock
Commit c1e2ee2dc436 ("memcg: replace ss->id_lock with a rwlock") has now
been seen to cause the unfair behavior we should have expected from
converting a spinlock to an rwlock: softlockup in cgroup_mkdir(), whose
get_new_cssid() is waiting for the wlock, while there are 19 tasks using
the rlock in css_get_next() to get on with their memcg workload (in an
artificial test, admittedly). Yet lib/idr.c was made suitable for RCU
way back: revert that commit, restoring ss->id_lock to a spinlock.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 21 Mar 2012 23:34:20 +0000 (16:34 -0700)]
idr: make idr_get_next() good for rcu_read_lock()
Make one small adjustment to idr_get_next(): take the height from the top
layer (stable under RCU) instead of from the root (unprotected by RCU), as
idr_find() does: so that it can be used with RCU locking. Copied comment
on RCU locking from idr_find().
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: remove unnecessary thp check in page stat accounting
Commit e94c8a9cbce1 ("memcg: make mem_cgroup_split_huge_fixup() more
efficient") removed move_lock_page_cgroup(). So we do not have to check
PageTransHuge in mem_cgroup_update_page_stat() and fallback into the
locked accounting because both move_account() and thp split are done
with compound_lock so they cannot race.
The race between update vs. move is protected by mem_cgroup_stealed.
PageTransHuge pages shouldn't appear in this code path currently because
we are tracking only file pages at the moment but later we are planning
to track also other pages (e.g. mlocked ones).
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Acked-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Acked-by: Ying Han<yinghan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 21 Mar 2012 23:34:19 +0000 (16:34 -0700)]
memcg: lru_size instead of MEM_CGROUP_ZSTAT
I never understood why we need a MEM_CGROUP_ZSTAT(mz, idx) macro to
obscure the LRU counts. For easier searching? So call it lru_size
rather than bare count (lru_length sounds better, but would be wrong,
since each huge page raises lru_size hugely).
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Kirill A. Shutemov <kirill@shutemov.name> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shaohua Li [Wed, 21 Mar 2012 23:34:17 +0000 (16:34 -0700)]
swap: don't do discard if no discard option added
When swapon() was not passed the SWAP_FLAG_DISCARD option, sys_swapon()
will still perform a discard operation. This can cause problems if
discard is slow or buggy.
Reverse the order of the check so that a discard operation is performed
only if the sys_swapon() caller is attempting to enable discard.
Reset the reclaim mode in shrink_active_list() to RECLAIM_MODE_SINGLE |
RECLAIM_MODE_ASYNC. (sync/async sign is used only in shrink_page_list
and does not affect shrink_active_list)
Currenly shrink_active_list() sometimes works in lumpy-reclaim mode, if
RECLAIM_MODE_LUMPYRECLAIM is left over from an earlier
shrink_inactive_list(). Meanwhile, in age_active_anon()
sc->reclaim_mode is totally zero. So the current behavior is too
complex and confusing, and this looks like bug.
In general, shrink_active_list() populates the inactive list for the
next shrink_inactive_list(). Lumpy shring_inactive_list() isolates
pages around the chosen one from both the active and inactive lists.
So, there is no reason for lumpy isolation in shrink_active_list().
See also: https://lkml.org/lkml/2012/3/15/583
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Proposed-by: Hugh Dickins <hughd@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kautuk Consul [Wed, 21 Mar 2012 23:34:16 +0000 (16:34 -0700)]
mmap.c: fix comment for __insert_vm_struct()
The comment above __insert_vm_struct seems to suggest that this function
is also going to link the VMA with the anon_vma, but this is not true.
This function only links the VMA to the mm->mm_rb tree and the mm->mmap
linked list.
[akpm@linux-foundation.org: improve comment layout and text] Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Steven Truelove [Wed, 21 Mar 2012 23:34:14 +0000 (16:34 -0700)]
hugetlbfs: fix alignment of huge page requests
When calling shmget() with SHM_HUGETLB, shmget aligns the request size to
PAGE_SIZE, but this is not sufficient.
Modify hugetlb_file_setup() to align requests to the huge page size, and
to accept an address argument so that all alignment checks can be
performed in hugetlb_file_setup(), rather than in its callers. Change
newseg() and mmap_pgoff() to match the new prototype and eliminate a now
redundant alignment check.
[akpm@linux-foundation.org: fix build] Signed-off-by: Steven Truelove <steven.truelove@utoronto.ca> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:34:13 +0000 (16:34 -0700)]
mm, hugetlb: add thread name and pid to SHM_HUGETLB mlock rlimit warning
Add the thread name and pid of the application that is allocating shm
segments with MAP_HUGETLB without being a part of
/proc/sys/vm/hugetlb_shm_group or having CAP_IPC_LOCK.
This identifies the application so it may be fixed by avoiding using the
deprecated exception (see Documentation/feature-removal-schedule.txt).
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:34:13 +0000 (16:34 -0700)]
mm, counters: remove task argument to sync_mm_rss() and __sync_task_rss_stat()
sync_mm_rss() can only be used for current to avoid race conditions in
iterating and clearing its per-task counters. Remove the task argument
for it and its helper function, __sync_task_rss_stat(), to avoid thinking
it can be used safely for anything other than current.
Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Gibson [Wed, 21 Mar 2012 23:34:12 +0000 (16:34 -0700)]
hugepages: fix use after free bug in "quota" handling
hugetlbfs_{get,put}_quota() are badly named. They don't interact with the
general quota handling code, and they don't much resemble its behaviour.
Rather than being about maintaining limits on on-disk block usage by
particular users, they are instead about maintaining limits on in-memory
page usage (including anonymous MAP_PRIVATE copied-on-write pages)
associated with a particular hugetlbfs filesystem instance.
Worse, they work by having callbacks to the hugetlbfs filesystem code from
the low-level page handling code, in particular from free_huge_page().
This is a layering violation of itself, but more importantly, if the
kernel does a get_user_pages() on hugepages (which can happen from KVM
amongst others), then the free_huge_page() can be delayed until after the
associated inode has already been freed. If an unmount occurs at the
wrong time, even the hugetlbfs superblock where the "quota" limits are
stored may have been freed.
Andrew Barry proposed a patch to fix this by having hugepages, instead of
storing a pointer to their address_space and reaching the superblock from
there, had the hugepages store pointers directly to the superblock,
bumping the reference count as appropriate to avoid it being freed.
Andrew Morton rejected that version, however, on the grounds that it made
the existing layering violation worse.
This is a reworked version of Andrew's patch, which removes the extra, and
some of the existing, layering violation. It works by introducing the
concept of a hugepage "subpool" at the lower hugepage mm layer - that is a
finite logical pool of hugepages to allocate from. hugetlbfs now creates
a subpool for each filesystem instance with a page limit set, and a
pointer to the subpool gets added to each allocated hugepage, instead of
the address_space pointer used now. The subpool has its own lifetime and
is only freed once all pages in it _and_ all other references to it (i.e.
superblocks) are gone.
subpools are optional - a NULL subpool pointer is taken by the code to
mean that no subpool limits are in effect.
Previous discussion of this bug found in: "Fix refcounting in hugetlbfs
quota handling.". See: https://lkml.org/lkml/2011/8/11/28 or
http://marc.info/?l=linux-mm&m=126928970510627&w=1
v2: Fixed a bug spotted by Hillf Danton, and removed the extra parameter to
alloc_huge_page() - since it already takes the vma, it is not necessary.
Signed-off-by: Andrew Barry <abarry@cray.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Gibson [Wed, 21 Mar 2012 23:34:12 +0000 (16:34 -0700)]
hugetlb: cleanup hugetlb.h
Make a couple of small cleanups to linux/include/hugetlb.h. The
set_file_hugepages() function, which was not used anywhere is removed,
and the hugetlbfs_config and hugetlbfs_inode_info structures with its
HUGETLBFS_I helper function are moved into inode.c, the only place they
were used.
These structures are really linked to the hugetlbfs filesystem
specifically not to hugepage mm handling in general, so they belong in
the filesystem code not in a generally available header.
It would be nice to move the hugetlbfs_sb_info (superblock) structure in
there as well, but it's currently needed in a number of places via the
hstate_vma() and hstate_inode().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Cc: Hugh Dickins <hughd@google.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Andrew Barry <abarry@cray.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Hillf Danton <dhillf@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Liu [Wed, 21 Mar 2012 23:34:11 +0000 (16:34 -0700)]
ksm: cleanup: introduce find_mergeable_vma()
There are multiple places which perform the same check. Add a new
find_mergeable_vma() to handle this.
Signed-off-by: Bob Liu <lliubbo@gmail.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Wed, 21 Mar 2012 23:34:11 +0000 (16:34 -0700)]
cpuset: mm: reduce large amounts of memory barrier related damage v3
Commit c0ff7453bb5c ("cpuset,mm: fix no node to alloc memory when
changing cpuset's mems") wins a super prize for the largest number of
memory barriers entered into fast paths for one commit.
[get|put]_mems_allowed is incredibly heavy with pairs of full memory
barriers inserted into a number of hot paths. This was detected while
investigating at large page allocator slowdown introduced some time
after 2.6.32. The largest portion of this overhead was shown by
oprofile to be at an mfence introduced by this commit into the page
allocator hot path.
For extra style points, the commit introduced the use of yield() in an
implementation of what looks like a spinning mutex.
This patch replaces the full memory barriers on both read and write
sides with a sequence counter with just read barriers on the fast path
side. This is much cheaper on some architectures, including x86. The
main bulk of the patch is the retry logic if the nodemask changes in a
manner that can cause a false failure.
While updating the nodemask, a check is made to see if a false failure
is a risk. If it is, the sequence number gets bumped and parallel
allocators will briefly stall while the nodemask update takes place.
In a page fault test microbenchmark, oprofile samples from
__alloc_pages_nodemask went from 4.53% of all samples to 1.15%. The
actual results were
The overall improvement is small but the System CPU time is much
improved and roughly in correlation to what oprofile reported (these
performance figures are without profiling so skew is expected). The
actual number of page faults is noticeably improved.
For benchmarks like kernel builds, the overall benefit is marginal but
the system CPU time is slightly reduced.
To test the actual bug the commit fixed I opened two terminals. The
first ran within a cpuset and continually ran a small program that
faulted 100M of anonymous data. In a second window, the nodemask of the
cpuset was continually randomised in a loop.
Without the commit, the program would fail every so often (usually
within 10 seconds) and obviously with the commit everything worked fine.
With this patch applied, it also worked fine so the fix should be
functionally equivalent.
Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Miao Xie <miaox@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:34:10 +0000 (16:34 -0700)]
mm, memcg: pass charge order to oom killer
The oom killer typically displays the allocation order at the time of oom
as a part of its diangostic messages (for global, cpuset, and mempolicy
ooms).
The memory controller may also pass the charge order to the oom killer so
it can emit the same information. This is useful in determining how large
the memory allocation is that triggered the oom killer.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Balbir Singh <bsingharora@gmail.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andi Kleen [Wed, 21 Mar 2012 23:34:09 +0000 (16:34 -0700)]
mm: update stale lock ordering comment for memory-failure.c
When i_mmap_lock changed to a mutex the locking order in memory failure
was changed to take the sleeping lock first. But the big fat mm lock
ordering comment (BFMLO) wasn't updated. Do this here.
Pointed out by Andrew.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fengguang Wu [Wed, 21 Mar 2012 23:34:09 +0000 (16:34 -0700)]
mm: use global_dirty_limit in throttle_vm_writeout()
When starting a memory hog task, a desktop box w/o swap is found to go
unresponsive for a long time. It's solely caused by lots of congestion
waits in throttle_vm_writeout():
The root cause is, the dirty threshold is knocked down a lot by the memory
hog task. Fixed by using global_dirty_limit which decreases gradually on
such events and can guarantee we stay above (the also decreasing) nr_dirty
in the progress of following down to the new dirty threshold.
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jan Kara <jack@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Ying Han <yinghan@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fengguang Wu [Wed, 21 Mar 2012 23:34:08 +0000 (16:34 -0700)]
mm: don't set __GFP_WRITE on ramfs/sysfs writes
There is not much point in skipping zones during allocation based on the
dirty usage which they'll never contribute to. And we'd like to avoid
page reclaim waits when writing to ramfs/sysfs etc.
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jan Kara <jack@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Ying Han <yinghan@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Minchan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlbfs: avoid taking i_mutex from hugetlbfs_read()
Taking i_mutex in hugetlbfs_read() can result in deadlock with mmap as
explained below
Thread A:
read() on hugetlbfs
hugetlbfs_read() called
i_mutex grabbed
hugetlbfs_read_actor() called
__copy_to_user() called
page fault is triggered
Thread B, sharing address space with A:
mmap() the same file
->mmap_sem is grabbed on task_B->mm->mmap_sem
hugetlbfs_file_mmap() is called
attempt to grab ->i_mutex and block waiting for A to give it up
Thread A:
pagefault handled blocked on attempt to grab task_A->mm->mmap_sem,
which happens to be the same thing as task_B->mm->mmap_sem. Block waiting
for B to give it up.
AFAIU the i_mutex locking was added to hugetlbfs_read() as per
http://lkml.indiana.edu/hypermail/linux/kernel/0707.2/3066.html to take
care of the race between truncate and read. This patch fixes this by
looking at page->mapping under lock_page() (find_lock_page()) to ensure
that the inode didn't get truncated in the range during a parallel read.
Ideally we can extend the patch to make sure we don't increase i_size in
mmap. But that will break userspace, because applications will now have
to use truncate(2) to increase i_size in hugetlbfs.
This is on a system with 8TB available via the AMS pool, and as a quirk
of AMS in firmware, all of that memory shows up in node 0. So, we end
up with an allocation that will fail the goal/limit constraints.
In theory, we could "fall-back" to alloc_bootmem_node() in
sparse_early_usemaps_alloc_node(), but since we actually have HOTREMOVE
defined, we'll BUG_ON() instead. A simple solution appears to be to
unconditionally remove the limit condition in alloc_bootmem_section,
meaning allocations are allowed to cross section boundaries (necessary
for systems of this size).
Johannes Weiner pointed out that if alloc_bootmem_section() no longer
guarantees section-locality, we need check_usemap_section_nr() to print
possible cross-dependencies between node descriptors and the usemaps
allocated through it. That makes the two loops in
sparse_early_usemaps_alloc_node() identical, so re-factor the code a
bit.
[akpm@linux-foundation.org: code simplification] Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Anton Blanchard <anton@au1.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: <stable@vger.kernel.org> [3.3.1] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: drain percpu lru add/rotate page-vectors on cpu hot-unplug
This cpu hotplug hook was accidentally removed in commit 00a62ce91e55
("mm: fix Committed_AS underflow on large NR_CPUS environment")
The visible effect of this accident: some pages are borrowed in per-cpu
page-vectors. Truncate can deal with it, but these pages cannot be
reused while this cpu is offline. So this is like a temporary memory
leak.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Eric B Munson <ebmunson@us.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Migration functions perform the rcu_read_unlock too early. As a result
the task pointed to may change from under us. This can result in an oops,
as reported by Dave Hansen in https://lkml.org/lkml/2012/2/23/302.
The following patch extend the period of the rcu_read_lock until after the
permissions checks are done. We also take a refcount so that the task
reference is stable when calling security check functions and performing
cpuset node validation (which takes a mutex).
The refcount is dropped before actual page migration occurs so there is no
change to the refcounts held during page migration.
Also move the determination of the mm of the task struct to immediately
before the do_migrate*() calls so that it is clear that we switch from
handling the task during permission checks to the mm for the actual
migration. Since the determination is only done once and we then no
longer use the task_struct we can be sure that we operate on a specific
address space that will not change from under us.
[akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Christoph Lameter <cl@linux.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Reported-by: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dean Nelson [Wed, 21 Mar 2012 23:34:05 +0000 (16:34 -0700)]
thp: allow a hwpoisoned head page to be put back to LRU
Andrea Arcangeli pointed out to me that a check in __memory_failure()
which was intended to prevent THP tail pages from being checked for the
absence of the PG_lru flag (something that is always the case), was also
preventing THP head pages from being checked.
A THP head page could actually benefit from the call to shake_page() by
ending up being put back to a LRU, provided it had been waiting in a
pagevec array.
Andrea suggested that the "!PageTransCompound(p)" in the if-statement
should be replaced by a "!PageTransTail(p)", thus allowing THP head pages
to be checked and possibly shaken.
Signed-off-by: Dean Nelson <dnelson@redhat.com> Cc: Jin Dongming <jin.dongming@np.css.fujitsu.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jarkko Sakkinen [Wed, 21 Mar 2012 23:34:05 +0000 (16:34 -0700)]
tmpfs: security xattr setting on inode creation
Adds to generic xattr support introduced in Linux 3.0 by implementing
initxattrs callback. This enables consulting of security attributes from
LSM and EVM when inode is created.
[hughd@google.com: moved under CONFIG_TMPFS_XATTR, with memcpy in shmem_xattr_alloc] Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:34:04 +0000 (16:34 -0700)]
mm, oom: force oom kill on sysrq+f
The oom killer chooses not to kill a thread if:
- an eligible thread has already been oom killed and has yet to exit,
and
- an eligible thread is exiting but has yet to free all its memory and
is not the thread attempting to currently allocate memory.
SysRq+F manually invokes the global oom killer to kill a memory-hogging
task. This is normally done as a last resort to free memory when no
progress is being made or to test the oom killer itself.
For both uses, we always want to kill a thread and never defer. This
patch causes SysRq+F to always kill an eligible thread and can be used to
force a kill even if another oom killed thread has failed to exit.
Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Pekka Enberg <penberg@kernel.org> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
procfs: mark thread stack correctly in proc/<pid>/maps
Stack for a new thread is mapped by userspace code and passed via
sys_clone. This memory is currently seen as anonymous in
/proc/<pid>/maps, which makes it difficult to ascertain which mappings
are being used for thread stacks. This patch uses the individual task
stack pointers to determine which vmas are actually thread stacks.
Here, one could guess that 7f8a44492000-7f8a44c92000 is a stack since
the earlier vma that has no permissions (7f8a44e3d000-7f8a4503d000) but
that is not always a reliable way to find out which vma is a thread
stack. Also, /proc/PID/maps and /proc/PID/task/TID/maps has the same
content.
With this patch in place, /proc/PID/task/TID/maps are treated as 'maps
as the task would see it' and hence, only the vma that that task uses as
stack is marked as [stack]. All other 'stack' vmas are marked as
anonymous memory. /proc/PID/maps acts as a thread group level view,
where all thread stack vmas are marked as [stack:TID] where TID is the
process ID of the task that uses that vma as stack, while the process
stack is marked as [stack].
Thus marking all vmas that are used as stacks by the threads in the
thread group along with the process stack. The task level maps will
however like this:
where only the vma that is being used as a stack by *that* task is
marked as [stack].
Analogous changes have been made to /proc/PID/smaps,
/proc/PID/numa_maps, /proc/PID/task/TID/smaps and
/proc/PID/task/TID/numa_maps. Relevant snippets from smaps and
numa_maps:
Jiri Kosina [Wed, 21 Mar 2012 23:34:02 +0000 (16:34 -0700)]
thp: documentation: 'transparent_hugepage=' can also be specified on cmdline
The behavior of THP can either be toggled through sysfs in runtime or
using a kernel cmdline parameter 'transparent_hugepage='. Document the
latter in kernel-parameters.txt
Signed-off-by: Jiri Kosina <jkosina@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hillf Danton [Wed, 21 Mar 2012 23:34:02 +0000 (16:34 -0700)]
vmscan: handle isolated pages with lru lock released
When shrinking inactive lru list, isolated pages are queued on locally
private list, so the lock-hold time could be reduced if pages are counted
without lock protection.
To achieve that, firstly updating reclaim stat is delayed until the
putback stage, after reacquiring the lru lock.
Secondly, operations related to vm and zone stats are now proteced with
preemption disabled as they are per-cpu operations.
Hillf Danton [Wed, 21 Mar 2012 23:34:00 +0000 (16:34 -0700)]
mm: hugetlb: defer freeing pages when gathering surplus pages
When gathering surplus pages, the number of needed pages is recomputed
after reacquiring hugetlb lock to catch changes in resv_huge_pages and
free_huge_pages. Plus it is recomputed with the number of newly allocated
pages involved.
Thus freeing pages can be deferred a bit to see if the final page request
is satisfied, though pages could be allocated less than needed.
Mel Gorman [Wed, 21 Mar 2012 23:34:00 +0000 (16:34 -0700)]
mm: vmscan: forcibly scan highmem if there are too many buffer_heads pinning highmem
Stuart Foster reported on bugzilla that copying large amounts of data
from NTFS caused an OOM kill on 32-bit X86 with 16G of memory. Andrew
Morton correctly identified that the problem was NTFS was using 512
blocks meaning each page had 8 buffer_heads in low memory pinning it.
In the past, direct reclaim used to scan highmem even if the allocating
process did not specify __GFP_HIGHMEM but not any more. kswapd no longer
will reclaim from zones that are above the high watermark. The intention
in both cases was to minimise unnecessary reclaim. The downside is on
machines with large amounts of highmem that lowmem can be fully consumed
by buffer_heads with nothing trying to free them.
The following patch is based on a suggestion by Andrew Morton to extend
the buffer_heads_over_limit case to force kswapd and direct reclaim to
scan the highmem zone regardless of the allocation request or watermarks.
mm: replace PAGE_MIGRATION with IS_ENABLED(CONFIG_MIGRATION)
Since commit 2a11c8ea20bf ("kconfig: Introduce IS_ENABLED(),
IS_BUILTIN() and IS_MODULE()") there is a generic grep-friendly method
for checking config options in C expressions.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Naoya Horiguchi [Wed, 21 Mar 2012 23:33:59 +0000 (16:33 -0700)]
pagemap: introduce data structure for pagemap entry
Currently a local variable of pagemap entry in pagemap_pte_range() is
named pfn and typed with u64, but it's not correct (pfn should be unsigned
long.)
This patch introduces special type for pagemap entries and replaces code
with it.
Naoya Horiguchi [Wed, 21 Mar 2012 23:33:58 +0000 (16:33 -0700)]
pagemap: document KPF_THP and make page-types aware of it
page-types, which is a common user of pagemap, gets aware of thp with this
patch. This helps system admins and kernel hackers know about how thp
works. Here is a sample output of page-types over a thp:
Naoya Horiguchi [Wed, 21 Mar 2012 23:33:57 +0000 (16:33 -0700)]
thp: optimize away unnecessary page table locking
Currently when we check if we can handle thp as it is or we need to split
it into regular sized pages, we hold page table lock prior to check
whether a given pmd is mapping thp or not. Because of this, when it's not
"huge pmd" we suffer from unnecessary lock/unlock overhead. To remove it,
this patch introduces a optimized check function and replace several
similar logics with it.
Naoya Horiguchi [Wed, 21 Mar 2012 23:33:57 +0000 (16:33 -0700)]
pagemap: avoid splitting thp when reading /proc/pid/pagemap
Thp split is not necessary if we explicitly check whether pmds are mapping
thps or not. This patch introduces this check and adds code to generate
pagemap entries for pmds mapping thps, which results in less performance
impact of pagemap on thp.
Xiao Guangrong [Wed, 21 Mar 2012 23:33:56 +0000 (16:33 -0700)]
mm: search from free_area_cache for the bigger size
If the required size is bigger than cached_hole_size it is better to
search from free_area_cache - it is easier to get a free region,
specifically for the 64 bit process whose address space is large enough
Do it just as hugetlb_get_unmapped_area_topdown() in arch/x86/mm/hugetlbpage.c
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Hillf Danton <dhillf@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xiao Guangrong [Wed, 21 Mar 2012 23:33:56 +0000 (16:33 -0700)]
mm: do not reset cached_hole_size when vma is unmapped
In the current code, cached_hole_size is set to the maximum value if the
unmapped vma is less that free_area_cache so the next search will search
from the base address.
Actually, we can keep cached_hole_size so that if the next required size
is more than cached_hole_size, it can search from free_area_cache.
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Hillf Danton <dhillf@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Carpenter [Wed, 21 Mar 2012 23:33:54 +0000 (16:33 -0700)]
mm: compaction: make compact_control order signed
"order" is -1 when compacting via /proc/sys/vm/compact_memory. Making
it unsigned causes a bug in __compact_pgdat() when we test:
if (cc->order < 0 || !compaction_deferred(zone, cc->order))
compact_zone(zone, cc);
[akpm@linux-foundation.org: make __compact_pgdat()'s comparison match other code sites] Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The RECLAIM_FS notations indicate that it's doing the GFP_FS checking that
Nick hacked into lockdep a while back: I think we're intended to read that
"<Interrupt>" in the DEADLOCK scenario as "<Direct reclaim>".
I'm hazy, I have not reached any conclusion as to whether it's right to
complain or not; but I believe it's uneasy about kswapd now doing the
mutex_lock(&pcpu_alloc_mutex) which lru_add_drain_all() entails. Nor have
I reached any conclusion as to whether it's important for kswapd to do
that draining or not.
But so as not to get blocked on this, with lockdep disabled from giving
further reports, here's a patch which removes the lru_add_drain_all() from
kswapd's callpath (and calls it only once from compact_nodes(), instead of
once per node).
Rik van Riel [Wed, 21 Mar 2012 23:33:52 +0000 (16:33 -0700)]
vmscan: only defer compaction for failed order and higher
Currently a failed order-9 (transparent hugepage) compaction can lead to
memory compaction being temporarily disabled for a memory zone. Even if
we only need compaction for an order 2 allocation, eg. for jumbo frames
networking.
The fix is relatively straightforward: keep track of the highest order at
which compaction is succeeding, and only defer compaction for orders at
which compaction is failing.
Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hillf Danton <dhillf@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Wed, 21 Mar 2012 23:33:52 +0000 (16:33 -0700)]
vmscan: kswapd carefully call compaction
With CONFIG_COMPACTION enabled, kswapd does not try to free contiguous
free pages, even when it is woken for a higher order request.
This could be bad for eg. jumbo frame network allocations, which are done
from interrupt context and cannot compact memory themselves. Higher than
before allocation failure rates in the network receive path have been
observed in kernels with compaction enabled.
Teach kswapd to defragment the memory zones in a node, but only if
required and compaction is not deferred in a zone.
[akpm@linux-foundation.org: reduce scope of zones_need_compaction] Signed-off-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hillf Danton <dhillf@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Wed, 21 Mar 2012 23:33:51 +0000 (16:33 -0700)]
vmscan: reclaim at order 0 when compaction is enabled
When built with CONFIG_COMPACTION, kswapd should not try to free
contiguous pages, because it is not trying hard enough to have a real
chance at being successful, but still disrupts the LRU enough to break
other things.
Do not do higher order page isolation unless we really are in lumpy
reclaim mode.
Stop reclaiming pages once we have enough free pages that compaction can
deal with things, and we hit the normal order 0 watermarks used by kswapd.
Also remove a line of code that increments balanced right before exiting
the function.
Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hillf Danton <dhillf@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Wed, 21 Mar 2012 23:33:50 +0000 (16:33 -0700)]
mm: make swapin readahead skip over holes
Ever since abandoning the virtual scan of processes, for scalability
reasons, swap space has been a little more fragmented than before. This
can lead to the situation where a large memory user is killed, swap space
ends up full of "holes" and swapin readahead is totally ineffective.
On my home system, after killing a leaky firefox it took over an hour to
page just under 2GB of memory back in, slowing the virtual machines down
to a crawl.
This patch makes swapin readahead simply skip over holes, instead of
stopping at them. This allows the system to swap things back in at rates
of several MB/second, instead of a few hundred kB/second.
The checks done in valid_swaphandles are already done in
read_swap_cache_async as well, allowing us to remove a fair amount of
code.
[akpm@linux-foundation.org: fix it for page_cluster >= 32] Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Adrian Drzewiecki <z@drze.net> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hillf Danton [Wed, 21 Mar 2012 23:33:50 +0000 (16:33 -0700)]
mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()
The value of nr_reclaimed is the number of pages reclaimed in the current
round of the loop, whereas nr_to_reclaim should be compared with the
number of pages reclaimed in all rounds.
In each round of the loop, reclaimed pages are cut off from the reclaim
goal, and the loop stops once the goal achieved.
Hillf Danton [Wed, 21 Mar 2012 23:33:48 +0000 (16:33 -0700)]
mm/vmscan.c: cleanup with s/reclaim_mode/isolate_mode/
With tons of reclaim_mode (defined as one field of struct scan_control)
already in the file, it is clearer to rename the local reclaim_mode when
setting up the isolation mode.
Signed-off-by: Hillf Danton <dhillf@gmail.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This check will prevent reoccurences of bugs such as that fixed in "mm:
fix rss count leakage during migration".
I didn't hide this check under CONFIG_VM_DEBUG because it rather small and
rss counters cover whole page-table management, so this is a good
invariant.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Hugh Dickins <hughd@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:33:47 +0000 (16:33 -0700)]
mm, oom: introduce independent oom killer ratelimit state
printk_ratelimit() uses the global ratelimit state for all printks. The
oom killer should not be subjected to this state just because another
subsystem or driver may be flooding the kernel log.
This patch introduces printk ratelimiting specifically for the oom killer.
Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:33:47 +0000 (16:33 -0700)]
mm, oom: do not emit oom killer warning if chosen thread is already exiting
If a thread is chosen for oom kill and is already PF_EXITING, then the oom
killer simply sets TIF_MEMDIE and returns. This allows the thread to have
access to memory reserves so that it may quickly exit. This logic is
preceeded with a comment saying there's no need to alarm the sysadmin.
This patch adds truth to that statement.
There's no need to emit any warning about the oom condition if the thread
is already exiting since it will not be killed. In this condition, just
silently return the oom killer since its only giving access to memory
reserves and is otherwise a no-op.
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 21 Mar 2012 23:33:46 +0000 (16:33 -0700)]
mm, oom: avoid looping when chosen thread detaches its mm
oom_kill_task() returns non-zero iff the chosen process does not have any
threads with an attached ->mm.
In such a case, it's better to just return to the page allocator and retry
the allocation because memory could have been freed in the interim and the
oom condition may no longer exist. It's unnecessary to loop in the oom
killer and find another thread to kill.
This allows both oom_kill_task() and oom_kill_process() to be converted to
void functions. If the oom condition persists, the oom killer will be
recalled.
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matt Fleming [Wed, 21 Mar 2012 23:33:46 +0000 (16:33 -0700)]
sparc: use block_sigmask()
Use the new helper function introduced in commit 5e6292c0f28f ("signal:
add block_sigmask() for adding sigmask to current->blocked") which
centralises the code for updating current->blocked after successfully
delivering a signal and reduces the amount of duplicate code across
architectures. In the past some architectures got this code wrong, so
using this helper function should stop that from happening again.
Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: "David S. Miller" <davem@davemloft.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matt Fleming [Wed, 21 Mar 2012 23:33:45 +0000 (16:33 -0700)]
xtensa: use set_current_blocked() and block_sigmask()
As described in commit e6fa16ab9c1e ("signal: sigprocmask() should do
retarget_shared_pending()") the modification of current->blocked is
incorrect as we need to check whether the signal we're about to block is
pending in the shared queue.
Also, use the new helper function introduced in commit 5e6292c0f28f
("signal: add block_sigmask() for adding sigmask to current->blocked")
which centralises the code for updating current->blocked after
successfully delivering a signal and reduces the amount of duplicate code
across architectures. In the past some architectures got this code wrong,
so using this helper function should stop that from happening again.
Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matt Fleming [Wed, 21 Mar 2012 23:33:45 +0000 (16:33 -0700)]
xtensa: don't mask signals if we fail to setup signal stack
setup_frame() needs to return an indication of whether it succeeded or
failed in setting up the signal stack frame. If setup_frame() fails then
we must not modify current->blocked.
Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matt Fleming [Wed, 21 Mar 2012 23:33:44 +0000 (16:33 -0700)]
xtensa: no need to reset handler if SA_ONESHOT
get_signal_to_deliver() already resets the signal handler if SA_ONESHOT
is set in ka->sa.sa_flags, there's no need to do it again in
handle_signal().
Furthermore, because we were modifying ka->sa.sa_handler (which is a
copy of sighand->action[]) instead of sighand->action[] the original
code actually had no effect on signal delivery.
Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matt Fleming [Wed, 21 Mar 2012 23:33:44 +0000 (16:33 -0700)]
xtensa: don't reimplement force_sigsegv()
Instead of open coding the sequence from force_sigsegv() just call it.
This also fixes a bug because we were modifying ka->sa.sa_handler (which
is a copy of sighand->action[]), whereas the intention of the code was to
modify sighand->action[] directly.
As the original code was working with a copy it had no effect on signal
delivery.
Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Earl Chew [Wed, 21 Mar 2012 23:33:43 +0000 (16:33 -0700)]
seq_file: fix mishandling of consecutive pread() invocations.
The following program illustrates the problem:
char buf[8192];
int fd = open("/proc/self/maps", O_RDONLY);
n = pread(fd, buf, sizeof(buf), 0);
printf("%d\n", n);
/* lseek(fd, 0, SEEK_CUR); */ /* Uncomment to work around */
n = pread(fd, buf, sizeof(buf), 0);
printf("%d\n", n);
The second printf() prints zero, but uncommenting the lseek() corrects its
behaviour.
To fix, make seq_read() mirror seq_lseek() when processing changes in
*ppos. Restore m->version first, then if required traverse and update
read_pos on success.
Fix a code indentation in the function intel_idle_cpu_init that looks
confusing.o
Suggested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Marcos Paulo de Souza <marcos.mage@gmail.com> Cc: "Brown, Len" <len.brown@intel.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Wed, 21 Mar 2012 23:33:42 +0000 (16:33 -0700)]
fs/namei.c: fix warnings on 32-bit
i386 allnoconfig:
fs/namei.c: In function 'has_zero':
fs/namei.c:1617: warning: integer constant is too large for 'unsigned long' type
fs/namei.c:1617: warning: integer constant is too large for 'unsigned long' type
fs/namei.c: In function 'hash_name':
fs/namei.c:1635: warning: integer constant is too large for 'unsigned long' type
There must be a tidier way of doing this.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In some cases it may happen that pmd_none_or_clear_bad() is called with
the mmap_sem hold in read mode. In those cases the huge page faults can
allocate hugepmds under pmd_none_or_clear_bad() and that can trigger a
false positive from pmd_bad() that will not like to see a pmd
materializing as trans huge.
It's not khugepaged causing the problem, khugepaged holds the mmap_sem
in write mode (and all those sites must hold the mmap_sem in read mode
to prevent pagetables to go away from under them, during code review it
seems vm86 mode on 32bit kernels requires that too unless it's
restricted to 1 thread per process or UP builds). The race is only with
the huge pagefaults that can convert a pmd_none() into a
pmd_trans_huge().
Effectively all these pmd_none_or_clear_bad() sites running with
mmap_sem in read mode are somewhat speculative with the page faults, and
the result is always undefined when they run simultaneously. This is
probably why it wasn't common to run into this. For example if the
madvise(MADV_DONTNEED) runs zap_page_range() shortly before the page
fault, the hugepage will not be zapped, if the page fault runs first it
will be zapped.
Altering pmd_bad() not to error out if it finds hugepmds won't be enough
to fix this, because zap_pmd_range would then proceed to call
zap_pte_range (which would be incorrect if the pmd become a
pmd_trans_huge()).
The simplest way to fix this is to read the pmd in the local stack
(regardless of what we read, no need of actual CPU barriers, only
compiler barrier needed), and be sure it is not changing under the code
that computes its value. Even if the real pmd is changing under the
value we hold on the stack, we don't care. If we actually end up in
zap_pte_range it means the pmd was not none already and it was not huge,
and it can't become huge from under us (khugepaged locking explained
above).
All we need is to enforce that there is no way anymore that in a code
path like below, pmd_trans_huge can be false, but pmd_none_or_clear_bad
can run into a hugepmd. The overhead of a barrier() is just a compiler
tweak and should not be measurable (I only added it for THP builds). I
don't exclude different compiler versions may have prevented the race
too by caching the value of *pmd on the stack (that hasn't been
verified, but it wouldn't be impossible considering
pmd_none_or_clear_bad, pmd_bad, pmd_trans_huge, pmd_none are all inlines
and there's no external function called in between pmd_trans_huge and
pmd_none_or_clear_bad).
if (pmd_trans_huge(*pmd)) {
if (next-addr != HPAGE_PMD_SIZE) {
VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem));
split_huge_page_pmd(vma->vm_mm, pmd);
} else if (zap_huge_pmd(tlb, vma, pmd, addr))
continue;
/* fall through */
}
if (pmd_none_or_clear_bad(pmd))
Because this race condition could be exercised without special
privileges this was reported in CVE-2012-1179.
The race was identified and fully explained by Ulrich who debugged it.
I'm quoting his accurate explanation below, for reference.
After the PMD table entry has been cleared, there is an inconsistency
between the actual number of PMD table entries that are mapping the page
and the page's map count (_mapcount field in struct page). When the page
is subsequently reclaimed, __split_huge_page() detects this inconsistency.
The root cause of the problem is a race of two threads in a multithreaded
process. Thread B incurs a page fault on a virtual address that has never
been accessed (PMD entry is zero) while Thread A is executing an madvise()
system call on a virtual address within the same 2 MB (huge page) range.
- Thread A is executing an madvise(..., MADV_DONTNEED) system call
on the virtual address range "A(range)" shown in the picture.
sys_madvise
// Acquire the semaphore in shared mode.
down_read(¤t->mm->mmap_sem)
...
madvise_vma
switch (behavior)
case MADV_DONTNEED:
madvise_dontneed
zap_page_range
unmap_vmas
unmap_page_range
zap_pud_range
zap_pmd_range
//
// Assume that this huge page has never been accessed.
// I.e. content of the PMD entry is zero (not mapped).
//
if (pmd_trans_huge(*pmd)) {
// We don't get here due to the above assumption.
}
//
// Assume that Thread B incurred a page fault and
.---------> // sneaks in here as shown below.
| //
| if (pmd_none_or_clear_bad(pmd))
| {
| if (unlikely(pmd_bad(*pmd)))
| pmd_clear_bad
| {
| pmd_ERROR
| // Log "bad pmd ..." message here.
| pmd_clear
| // Clear the page's PMD entry.
| // Thread B incremented the map count
| // in page_add_new_anon_rmap(), but
| // now the page is no longer mapped
| // by a PMD entry (-> inconsistency).
| }
| }
|
v
- Thread B is handling a page fault on virtual address "B(fault)" shown
in the picture.
...
do_page_fault
__do_page_fault
// Acquire the semaphore in shared mode.
down_read_trylock(&mm->mmap_sem)
...
handle_mm_fault
if (pmd_none(*pmd) && transparent_hugepage_enabled(vma))
// We get here due to the above assumption (PMD entry is zero).
do_huge_pmd_anonymous_page
alloc_hugepage_vma
// Allocate a new transparent huge page here.
...
__do_huge_pmd_anonymous_page
...
spin_lock(&mm->page_table_lock)
...
page_add_new_anon_rmap
// Here we increment the page's map count (starts at -1).
atomic_set(&page->_mapcount, 0)
set_pmd_at
// Here we set the page's PMD entry which will be cleared
// when Thread A calls pmd_clear_bad().
...
spin_unlock(&mm->page_table_lock)
The mmap_sem does not prevent the race because both threads are acquiring
it in shared mode (down_read). Thread B holds the page_table_lock while
the page's map count and PMD table entry are updated. However, Thread A
does not synchronize on that lock.
====== end quote =======
[akpm@linux-foundation.org: checkpatch fixes] Reported-by: Ulrich Obergfell <uobergfe@redhat.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Jones <davej@redhat.com> Acked-by: Larry Woodman <lwoodman@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: <stable@vger.kernel.org> [2.6.38+] Cc: Mark Salter <msalter@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Wed, 21 Mar 2012 17:37:25 +0000 (10:37 -0700)]
Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon changes for v3.4 from Guenter Roeck:
"Mostly cleanup. No new drivers this time around, but support for
several chips added to existing drivers: TPS40400, TPS40422, MTD040,
MAX34446, ZL9101M, ZL9117M, and LM96080. Also, added watchdog support
for SCH56xx, and additional attributes for a couple of drivers."
* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (137 commits)
hwmon: (sch56xx) Add support for the integrated watchdog (v2)
hwmon: (w83627ehf) Add support for temperature offset registers
hwmon: (jc42) Remove unnecessary device IDs
hwmon: (zl6100) Add support for ZL9101M and ZL9117M
hwmon: (adm1275) Add support for ADM1075
hwmon: (max34440) Add support for MAX34446
hwmon: (pmbus) Add more virtual registers
hwmon: (pmbus) Add support for Lineage Power MDT040
hwmon: (pmbus) Add support for TI TPS40400 and TPS40422
hwmon: (max34440) Add support for 'lowest' output voltage attribute
hwmon: (jc42) Convert to use devm_kzalloc
hwmon: (max16065) Convert to use devm_kzalloc
hwmon: (smm665) Convert to use devm_kzalloc
hwmon: (ltc4261) Convert to use devm_kzalloc
hwmon: (pmbus) Simplify remove functions
hwmon: (pmbus) Convert pmbus drivers to use devm_kzalloc
hwmon: (lineage-pem) Convert to use devm_kzalloc
hwmon: (hwmon-vid) Fix checkpatch issues
hwmon: (hwmon-vid) Add new entries to VRM model table
hwmon: (lm80) Add detection of NatSemi/TI LM96080
...
Linus Torvalds [Wed, 21 Mar 2012 17:34:56 +0000 (10:34 -0700)]
Merge tag 'regulator-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator updates for 3.4 from Mark Brown:
"This has been a fairly quiet release from a regulator point of view,
the only real framework features added were devm support and a
convenience helper for setting up fixed voltage regulators.
We also added a couple of drivers (but will drop the BQ240022 driver
via the arm-soc tree as it's been replaced by the more generic
gpio-regulator driver) and Axel Lin continued his relentless and
generally awesome stream of fixes and cleanups."
* tag 'regulator-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (93 commits)
regulator: Fix up a confusing dev_warn when DT lookup fails
regulator: Convert tps6507x to set_voltage_sel
regulator: Refactor tps6507x to use one tps6507x_pmic_ops for all LDOs and DCDCs
regulator: Make s5m8767_get_voltage_register always return correct register
regulator: s5m8767: Check pdata->buck[2|3|4]_gpiodvs earlier
regulator: tps65910: Provide settling time for DCDC voltage change
regulator: Add Anatop regulator driver
regulator: Simplify implementation of tps65912_get_voltage_dcdc
regulator: Use tps65912_set_voltage_sel for both DCDCx and LDOx
regulator: tps65910: Provide settling time for enabling rails
regulator: max8925: Use DIV_ROUND_UP macro
regulator: tps65912: Use simple equations to get register address
regulator: Fix the logic of tps65910_get_mode
regulator: Merge tps65217_pmic_ldo234_ops and tps65217_pmic_dcdc_ops to tps65217_pmic_ops
regulator: Use DIV_ROUND_CLOSEST in wm8350_isink_get_current
regulator: Use array to store dcdc_range settings for tps65912
regulator: Rename s5m8767_convert_voltage to s5m8767_convert_voltage_to_sel
regulator: tps6524x: Remove unneeded comment for N_REGULATORS
regulator: Rename set_voltage_sel callback function name to *_sel
regulator: Fix s5m8767_set_voltage_time_sel calculation value
...
Linus Torvalds [Wed, 21 Mar 2012 17:33:42 +0000 (10:33 -0700)]
Merge tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
Pull InfiniBand/RDMA changes for the 3.4 merge window from Roland Dreier:
"Nothing big really stands out; by patch count lots of fixes to the
mlx4 driver plus some cleanups and fixes to the core and other
drivers."
* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (28 commits)
mlx4_core: Scale size of MTT table with system RAM
mlx4_core: Allow dynamic MTU configuration for IB ports
IB/mlx4: Fix info returned when querying IBoE ports
IB/mlx4: Fix possible missed completion event
mlx4_core: Report thermal error events
mlx4_core: Fix one more static exported function
IB: Change CQE "csum_ok" field to a bit flag
RDMA/iwcm: Reject connect requests if cmid is not in LISTEN state
RDMA/cxgb3: Don't pass irq flags to flush_qp()
mlx4_core: Get rid of redundant ext_port_cap flags
RDMA/ucma: Fix AB-BA deadlock
IB/ehca: Fix ilog2() compile failure
IB: Use central enum for speed instead of hard-coded values
IB/iser: Post initial receive buffers before sending the final login request
IB/iser: Free IB connection resources in the proper place
IB/srp: Consolidate repetitive sysfs code
IB/srp: Use pr_fmt() and pr_err()/pr_warn()
IB/core: Fix SDR rates in sysfs
mlx4: Enforce device max FMR maps in FMR alloc
IB/mlx4: Set bad_wr for invalid send opcode
...
Linus Torvalds [Wed, 21 Mar 2012 17:32:00 +0000 (10:32 -0700)]
Merge tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6
Pull SPI changes for v3.4 from Grant Likely:
"Mostly a bunch of new drivers and driver bug fixes; but this also
includes a few patches that create a core message queue infrastructure
for the spi subsystem instead of making each driver open code it."
* tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6: (34 commits)
spi/fsl-espi: Make sure pm is within 2..32
spi/fsl-espi: make the clock computation easier to read
spi: sh-hspi: modify write/read method
spi: sh-hspi: control spi clock more correctly
spi: sh-hspi: convert to using core message queue
spi: s3c64xx: Fix build
spi: s3c64xx: remove unnecessary callback msg->complete
spi: remove redundant variable assignment
spi: release lock on error path in spi_pump_messages()
spi: Compatibility with direction which is used in samsung DMA operation
spi-topcliff-pch: add recovery processing in case wait-event timeout
spi-topcliff-pch: supports a spi mode setup and bit order setup by IO control
spi-topcliff-pch: Fix issue for transmitting over 4KByte
spi-topcliff-pch: Modify pci-bus number dynamically to get DMA device info
spi/imx: simplify error handling to free gpios
spi: Convert to DEFINE_PCI_DEVICE_TABLE
spi: add Broadcom BCM63xx SPI controller driver
SPI: add CSR SiRFprimaII SPI controller driver
spi-topcliff-pch: fix -Wuninitialized warning
spi: Mark spi_register_board_info() __devinit
...
Linus Torvalds [Wed, 21 Mar 2012 17:30:03 +0000 (10:30 -0700)]
Merge tag 'dt-for-linus' of git://git.secretlab.ca/git/linux-2.6
Pull core device tree changes for Linux v3.4 from Grant Likely:
"This branch contains a minor documentation addition, a utility
function for parsing string properties needed by some of the new ARM
platforms, disables dynamic DT code that isn't used anywhere but on a
few PPC machines, and exports DT node compatible data to userspace via
UEVENT properties. Nothing earth shattering here."
* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux-2.6:
of: Only compile OF_DYNAMIC on PowerPC pseries and iseries
arm/dts: OMAP3: Add omap3evm and am335xevm support
drivercore: Output common devicetree information in uevent
of: Add of_property_match_string() to find index into a string list
Linus Torvalds [Wed, 21 Mar 2012 17:27:19 +0000 (10:27 -0700)]
Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6
Pull irq_domain support for all architectures from Grant Likely:
"Generialize powerpc's irq_host as irq_domain
This branch takes the PowerPC irq_host infrastructure (reverse mapping
from Linux IRQ numbers to hardware irq numbering), generalizes it,
renames it to irq_domain, and makes it available to all architectures.
Originally the plan has been to create an all-new irq_domain
implementation which addresses some of the powerpc shortcomings such
as not handling 1:1 mappings well, but doing that proved to be far
more difficult and invasive than generalizing the working code and
refactoring it in-place. So, this branch rips out the 'new'
irq_domain and replaces it with the modified powerpc version (in a
fully bisectable way of course). It converts all users over to the
new API and makes irq_domain selectable on any architecture.
No architecture is forced to enable irq_domain, but the infrastructure
is required for doing OpenFirmware style irq translations. It will
even work on SPARC even though SPARC has it's own mechanism for
translating irqs at boot time. MIPS, microblaze, embedded x86 and c6x
are converted too.
The resulting irq_domain code is probably still too verbose and can be
optimized more, but that can be done incrementally and is a task for
follow-on patches."
* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: (31 commits)
dt: fix twl4030 for non-dt compile on x86
mfd: twl-core: Add IRQ_DOMAIN dependency
devicetree: Add empty of_platform_populate() for !CONFIG_OF_ADDRESS (sparc)
irq_domain: Centralize definition of irq_dispose_mapping()
irq_domain/mips: Allow irq_domain on MIPS
irq_domain/x86: Convert x86 (embedded) to use common irq_domain
ppc-6xx: fix build failure in flipper-pic.c and hlwd-pic.c
irq_domain/microblaze: Convert microblaze to use irq_domains
irq_domain/powerpc: Replace custom xlate functions with library functions
irq_domain/powerpc: constify irq_domain_ops
irq_domain/c6x: Use library of xlate functions
irq_domain/c6x: constify irq_domain structures
irq_domain/c6x: Convert c6x to use generic irq_domain support.
irq_domain: constify irq_domain_ops
irq_domain: Create common xlate functions that device drivers can use
irq_domain: Remove irq_domain_add_simple()
irq_domain: Remove 'new' irq_domain in favour of the ppc one
mfd: twl-core.c: Fix the number of interrupts managed by twl4030
of/address: add empty static inlines for !CONFIG_OF
irq_domain: Add support for base irq and hwirq in legacy mappings
...
Linus Torvalds [Wed, 21 Mar 2012 17:15:51 +0000 (10:15 -0700)]
Merge tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates for 3.4 from Rafael Wysocki:
"Assorted extensions and fixes including:
* Introduction of early/late suspend/hibernation device callbacks.
* Generic PM domains extensions and fixes.
* devfreq updates from Axel Lin and MyungJoo Ham.
* Device PM QoS updates.
* Fixes of concurrency problems with wakeup sources.
* System suspend and hibernation fixes."
* tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (43 commits)
PM / Domains: Check domain status during hibernation restore of devices
PM / devfreq: add relation of recommended frequency.
PM / shmobile: Make MTU2 driver use pm_genpd_dev_always_on()
PM / shmobile: Make CMT driver use pm_genpd_dev_always_on()
PM / shmobile: Make TMU driver use pm_genpd_dev_always_on()
PM / Domains: Introduce "always on" device flag
PM / Domains: Fix hibernation restore of devices, v2
PM / Domains: Fix handling of wakeup devices during system resume
sh_mmcif / PM: Use PM QoS latency constraint
tmio_mmc / PM: Use PM QoS latency constraint
PM / QoS: Make it possible to expose PM QoS latency constraints
PM / Sleep: JBD and JBD2 missing set_freezable()
PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case
PM / Freezer: Remove references to TIF_FREEZE in comments
PM / Sleep: Add more wakeup source initialization routines
PM / Hibernate: Enable usermodehelpers in hibernate() error path
PM / Sleep: Make __pm_stay_awake() delete wakeup source timers
PM / Sleep: Fix race conditions related to wakeup source timer function
PM / Sleep: Fix possible infinite loop during wakeup source destruction
PM / Hibernate: print physical addresses consistently with other parts of kernel
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Linus Torvalds [Wed, 21 Mar 2012 16:40:26 +0000 (09:40 -0700)]
Merge branch 'kmap_atomic' of git://github.com/congwang/linux
Pull kmap_atomic cleanup from Cong Wang.
It's been in -next for a long time, and it gets rid of the (no longer
used) second argument to k[un]map_atomic().
Fix up a few trivial conflicts in various drivers, and do an "evil
merge" to catch some new uses that have come in since Cong's tree.
* 'kmap_atomic' of git://github.com/congwang/linux: (59 commits)
feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal
highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
drbd: remove the second argument of k[un]map_atomic()
zcache: remove the second argument of k[un]map_atomic()
gma500: remove the second argument of k[un]map_atomic()
dm: remove the second argument of k[un]map_atomic()
tomoyo: remove the second argument of k[un]map_atomic()
sunrpc: remove the second argument of k[un]map_atomic()
rds: remove the second argument of k[un]map_atomic()
net: remove the second argument of k[un]map_atomic()
mm: remove the second argument of k[un]map_atomic()
lib: remove the second argument of k[un]map_atomic()
power: remove the second argument of k[un]map_atomic()
kdb: remove the second argument of k[un]map_atomic()
udf: remove the second argument of k[un]map_atomic()
ubifs: remove the second argument of k[un]map_atomic()
squashfs: remove the second argument of k[un]map_atomic()
reiserfs: remove the second argument of k[un]map_atomic()
ocfs2: remove the second argument of k[un]map_atomic()
ntfs: remove the second argument of k[un]map_atomic()
...
Linus Torvalds [Wed, 21 Mar 2012 04:11:42 +0000 (21:11 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
Pull HID updates from Jiri Kosina:
"It contains HID driver updates all over the place -- a lot of new
hardware support especially in the multitouch area, including generic
handling of all multitouch devices by the hid-multitiouch driver
automatically."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (42 commits)
HID: multitouch: add PID for Fructel product
HID: wacom: Add reporting of wheel for Intuos4 WL
HID: wacom: Replace __set_bit with input_set_capability
HID: tivo: add support for BT-version (0x1200)
HID: wacom: Reset stylus buttons - Intuos4 WL
HID: multitouch: detect serial protocol
HID: handle all multitouch devices through hid-multitouch
HID: multitouch: fix handling of buggy reports descriptors for Dell ST2220T
HID: make it possible to force hid-core claim the device
HID: multitouch: add support for eGalax 0x722a
HID: usbhid: add quirk no_get for quanta 3008 devices
HID: multitouch: add more eGalax devices
HID: multitouch: add new PID from Ideacom
HID: multitouch: add support for Atmel maXTouch 03eb:2118
HID: waltop: Add support for tablet with PID 0038
HID: waltop: Replace original rdescs with links
HID: uclogic: Replace original rdescs with links
HID: wacom: Add pad buttons reporting on Intuos4 WL
HID: wacom: report distance for Intuos4 WL
HID: kye: Add support for 3 tablets
...
Pull networking merge from David Miller:
"1) Move ixgbe driver over to purely page based buffering on receive.
From Alexander Duyck.
2) Add receive packet steering support to e1000e, from Bruce Allan.
3) Convert TCP MD5 support over to RCU, from Eric Dumazet.
4) Reduce cpu usage in handling out-of-order TCP packets on modern
systems, also from Eric Dumazet.
5) Support the IP{,V6}_UNICAST_IF socket options, making the wine
folks happy, from Erich Hoover.
6) Support VLAN trunking from guests in hyperv driver, from Haiyang
Zhang.
7) Support byte-queue-limtis in r8169, from Igor Maravic.
8) Outline code intended for IP_RECVTOS in IP_PKTOPTIONS existed but
was never properly implemented, Jiri Benc fixed that.
9) 64-bit statistics support in r8169 and 8139too, from Junchang Wang.
10) Support kernel side dump filtering by ctmark in netfilter
ctnetlink, from Pablo Neira Ayuso.
11) Support byte-queue-limits in gianfar driver, from Paul Gortmaker.
12) Add new peek socket options to assist with socket migration, from
Pavel Emelyanov.
13) Add sch_plug packet scheduler whose queue is controlled by
userland daemons using explicit freeze and release commands. From
Shriram Rajagopalan.
14) Fix FCOE checksum offload handling on transmit, from Yi Zou."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1846 commits)
Fix pppol2tp getsockname()
Remove printk from rds_sendmsg
ipv6: fix incorrent ipv6 ipsec packet fragment
cpsw: Hook up default ndo_change_mtu.
net: qmi_wwan: fix build error due to cdc-wdm dependecy
netdev: driver: ethernet: Add TI CPSW driver
netdev: driver: ethernet: add cpsw address lookup engine support
phy: add am79c874 PHY support
mlx4_core: fix race on comm channel
bonding: send igmp report for its master
fs_enet: Add MPC5125 FEC support and PHY interface selection
net: bpf_jit: fix BPF_S_LDX_B_MSH compilation
net: update the usage of CHECKSUM_UNNECESSARY
fcoe: use CHECKSUM_UNNECESSARY instead of CHECKSUM_PARTIAL on tx
net: do not do gso for CHECKSUM_UNNECESSARY in netif_needs_gso
ixgbe: Fix issues with SR-IOV loopback when flow control is disabled
net/hyperv: Fix the code handling tx busy
ixgbe: fix namespace issues when FCoE/DCB is not enabled
rtlwifi: Remove unused ETH_ADDR_LEN defines
igbvf: Use ETH_ALEN
...
Fix up fairly trivial conflicts in drivers/isdn/gigaset/interface.c and
drivers/net/usb/{Kconfig,qmi_wwan.c} as per David.
Linus Torvalds [Wed, 21 Mar 2012 01:11:21 +0000 (18:11 -0700)]
Merge branch 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup changes from Tejun Heo:
"Out of the 8 commits, one fixes a long-standing locking issue around
tasklist walking and others are cleanups."
* 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: Walk task list under tasklist_lock in cgroup_enable_task_cg_list
cgroup: Remove wrong comment on cgroup_enable_task_cg_list()
cgroup: remove cgroup_subsys argument from callbacks
cgroup: remove extra calls to find_existing_css_set
cgroup: replace tasklist_lock with rcu_read_lock
cgroup: simplify double-check locking in cgroup_attach_proc
cgroup: move struct cgroup_pidlist out from the header file
cgroup: remove cgroup_attach_task_current_cg()
Oleg Nesterov [Mon, 19 Mar 2012 16:03:41 +0000 (17:03 +0100)]
exit_signal: fix the "parent has changed security domain" logic
exit_notify() changes ->exit_signal if the parent already did exec.
This doesn't really work, we are not going to send the signal now
if there is another live thread or the exiting task is traced. The
parent can exec before the last dies or the tracer detaches.
Move this check into do_notify_parent() which actually sends the
signal.
The user-visible change is that we do not change ->exit_signal,
and thus the exiting task is still "clone children" for
do_wait()->eligible_child(__WCLONE). Hopefully this is fine, the
current logic is racy anyway.
Oleg Nesterov [Mon, 19 Mar 2012 16:03:22 +0000 (17:03 +0100)]
exit_signal: simplify the "we have changed execution domain" logic
exit_notify() checks "tsk->self_exec_id != tsk->parent_exec_id"
to handle the "we have changed execution domain" case.
We can change do_thread() to always set ->exit_signal = SIGCHLD
and remove this check to simplify the code.
We could change setup_new_exec() instead, this looks more logical
because it increments ->self_exec_id. But note that de_thread()
already resets ->exit_signal if it changes the leader, let's keep
both changes close to each other.
Note that we change ->exit_signal lockless, this changes the rules.
Thereafter ->exit_signal is not stable under tasklist but this is
fine, the only possible change is OLDSIG -> SIGCHLD. This can race
with eligible_child() but the race is harmless. We can race with
reparent_leader() which changes our ->exit_signal in parallel, but
it does the same change to SIGCHLD.
The noticeable user-visible change is that the execing task is not
"visible" to do_wait()->eligible_child(__WCLONE) right after exec.
To me this looks more logical, and this is consistent with mt case.
projects / linux-beck.git / log