mm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures
If allocation fails after compaction then compaction may be deferred for a
number of allocation attempts. If there are subsequent failures,
compact_defer_shift is increased to defer for longer periods. This patch
uses that information to scale the number of pages reclaimed with
compact_defer_shift until allocations succeed again. The rationale is
that reclaiming the normal number of pages still allowed compaction to
fail and its success depends on the number of pages. If it's failing,
reclaim more pages until it succeeds again.
Note that this is not implying that VM reclaim is not reclaiming enough
pages or that its logic is broken. try_to_free_pages() always asks for
SWAP_CLUSTER_MAX pages to be reclaimed regardless of order and that is
what it does. Direct reclaim stops normally with this check.
if (sc->nr_reclaimed >= sc->nr_to_reclaim)
goto out;
should_continue_reclaim delays when that check is made until a minimum
number of pages for reclaim/compaction are reclaimed. It is possible that
this patch could instead set nr_to_reclaim in try_to_free_pages() and
drive it from there but that's behaves differently and not necessarily for
the better. If driven from do_try_to_free_pages(), it is also possible
that priorities will rise. When they reach DEF_PRIORITY-2, it will also
start stalling and setting pages for immediate reclaim which is more
disruptive than not desirable in this case. That is a more wide-reaching
change that could cause another regression related to THP requests causing
interactive jitter.
Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm: compaction: update comment in try_to_compact_pages
Allocation success rates have been far lower since 3.4 due to commit fe2c2a10 ("vmscan: reclaim at order 0 when compaction is enabled"). This
commit was introduced for good reasons and it was known in advance that
the success rates would suffer but it was justified on the grounds that
the high allocation success rates were achieved by aggressive reclaim.
Success rates are expected to suffer even more in 3.6 due to commit 7db8889a ("mm: have order > 0 compaction start off where it left") which
testing has shown to severely reduce allocation success rates under load -
to 0% in one case.
This series aims to improve the allocation success rates without
regressing the benefits of commit fe2c2a10. The series is based on latest
mmotm and takes into account the __GFP_NO_KSWAPD flag is going away.
Patch 1 updates a stale comment seeing as I was in the general area.
Patch 2 updates reclaim/compaction to reclaim pages scaled on the number
of recent failures.
Patch 3 captures suitable high-order pages freed by compaction to reduce
races with parallel allocation requests.
Patch 4 fixes the upstream commit [7db8889a: mm: have order > 0 compaction
start off where it left] to enable compaction again
Patch 5 identifies when compacion is taking too long due to contention
and aborts.
From
http://www.csn.ul.ie/~mel/postings/mmtests-20120424/global-dhp__stress-highalloc-performance-ext3/hydra/comparison.html
I know that the allocation success rates in 3.3.6 was 78% in comparison to
36% in in the current akpm tree. With the full series applied, the
success rates are up to around 51% with some variability in the results.
This is not as high a success rate but it does not reclaim excessively
which is a key point.
Note that swap in/out rates remain at 0. In 3.3.6 with 78% success rates
there were 71881 pages swapped out.
Direct pages scanned 70942 122976
Kswapd pages scanned 13663001520122
Kswapd pages reclaimed 13662141484629
Direct pages reclaimed 70936 105716
Kswapd efficiency 99% 97%
Kswapd velocity 1072.550 1182.615
Direct efficiency 99% 85%
Direct velocity 55.690 95.672
The kswapd velocity changes very little as expected. kswapd velocity is
around the 1000 pages/sec mark where as in kernel 3.3.6 with the high
allocation success rates it was 8140 pages/second. Direct velocity is
higher as a result of patch 2 of the series but this is expected and is
acceptable. The direct reclaim and kswapd velocities change very little.
If these get accepted for merging then there is a difficulty in how they
should be handled. 7db8889a ("mm: have order > 0 compaction start off
where it left") is broken but it is already in 3.6-rc1 and needs to be
fixed. However, if just patch 4 from this series is applied then Jim
Schutt's workload is known to break again as his workload also requires
patch 5. While it would be preferred to have all these patches in 3.6 to
improve compaction in general, it would at least be acceptable if just
patches 4 and 5 were merged to 3.6 to fix a known problem without breaking
compaction completely. On the face of it, that would force
__GFP_NO_KSWAPD patches to be merged at the same time but I can do a
version of this series with __GFP_NO_KSWAPD change reverted and then
rebase it on top of this series. That might be best overall because I
note that the __GFP_NO_KSWAPD patch should have removed
deferred_compaction from page_alloc.c but it didn't but fixing that causes
collisions with this series.
This patch:
The comment about order applied when the check was order >
PAGE_ALLOC_COSTLY_ORDER which has not been the case since c5a73c3d ("thp:
use compaction for all allocation orders"). Fixing the comment while I'm
in the general area.
Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Strangely, I can no longer get an uninitialized variable warning out of
copy_vma(), with or without the BUG() there; but David Rientjes gets it
when he builds with CONFIG_BUG off, which is understandable.
uninitialized_var() can be a useful tool, but I do prefer to avoid it:
partly because it might hide future errors, partly because I misspell it,
but mainly because the need for it comes and goes so mysteriously.
Given David's preference for no warning, mine for no uninitialized_var,
and Linus's for renaming BUG() to I_AM_A_MORON() to discourage its use in
the first place: copy_vma() seems a prime candidate for returning failure
to mremap instead of crashing the system.
Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: Hillf Danton <dhillf@gmail.com> Tested-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm/mmap.c: replace find_vma_prepare() with clearer find_vma_links()
People get confused by find_vma_prepare(), because it doesn't care about
what it returns in its output args, when its callers won't be interested.
Clarify by passing in end-of-range address too, and returning failure if
any existing vma overlaps the new range: instead of returning an ambiguous
vma which most callers then must check. find_vma_links() is a clearer
name.
This does revert 2.6.27's dfe195fb79e88 ("mm: fix uninitialized variables
for find_vma_prepare callers"), but it looks like gcc 4.3.0 was one of
those releases too eager to shout about uninitialized variables: only
copy_vma() warns with 4.5.1 and 4.7.1, which a BUG on error silences.
Robin Dong [Fri, 28 Sep 2012 00:19:07 +0000 (10:19 +1000)]
mm: fix nonuniform page status when writing new file with small buffer
When writing a new file with 2048 bytes buffer, such as write(fd, buffer,
2048), it will call generic_perform_write() twice for every page:
write_begin
mark_page_accessed(page)
write_end
write_begin
mark_page_accessed(page)
write_end
Pages 1-13 will be added to lru-pvecs in write_begin() and will *NOT* be
added to active_list even they have be accessed twice because they are not
PageLRU(page). But when page 14th comes, all pages in lru-pvecs will be
moved to inactive_list (by __lru_cache_add() ) in first write_begin(), now
page 14th *is* PageLRU(page). And after second write_end() only page 14th
will be in active_list.
In Hadoop environment, we do comes to this situation: after writing a
file, we find out that only 14th, 28th, 42th... page are in active_list
and others in inactive_list. Now kswapd works, shrinks the inactive_list,
the file only have 14th, 28th...pages in memory, the readahead request
size will be broken to only 52k (13*4k), system's performance falls
dramatically.
This problem can also replay by below steps (the machine has 8G memory):
1. dd if=/dev/zero of=/test/file.out bs=1024 count=1048576
2. cat another 7.5G file to /dev/null
3. vmtouch -m 1G -v /test/file.out, it will show:
mm: kill vma flag VM_RESERVED and mm->reserved_vm counter
A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA,
currently it lost original meaning but still has some effects:
| effect | alternative flags
-+------------------------+---------------------------------------------
1| account as reserved_vm | VM_IO
2| skip in core dump | VM_IO, VM_DONTDUMP
3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
4| do not mlock | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
This patch removes reserved_vm counter from mm_struct. Seems like nobody
cares about it, it does not exported into userspace directly, it only
reduces total_vm showed in proc.
Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP.
remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP.
remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename VM_NODUMP into VM_DONTDUMP: this name matches other negative flags:
VM_DONTEXPAND, VM_DONTCOPY. Currently this flag used only for
sys_madvise. The next patch will use it for replacing the outdated flag
VM_RESERVED.
Also forbid madvise(MADV_DODUMP) for special kernel mappings VM_SPECIAL
(VM_IO | VM_DONTEXPAND | VM_RESERVED | VM_PFNMAP)
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm: kill vma flag VM_EXECUTABLE and mm->num_exe_file_vmas
Currently the kernel sets mm->exe_file during sys_execve() and then tracks
number of vmas with VM_EXECUTABLE flag in mm->num_exe_file_vmas, as soon
as this counter drops to zero kernel resets mm->exe_file to NULL. Plus it
resets mm->exe_file at last mmput() when mm->mm_users drops to zero.
VMA with VM_EXECUTABLE flag appears after mapping file with flag
MAP_EXECUTABLE, such vmas can appears only at sys_execve() or after vma
splitting, because sys_mmap ignores this flag. Usually binfmt module sets
mm->exe_file and mmaps executable vmas with this file, they hold
mm->exe_file while task is running.
comment from v2.6.25-6245-g925d1c4 ("procfs task exe symlink"),
where all this stuff was introduced:
> The kernel implements readlink of /proc/pid/exe by getting the file from
> the first executable VMA. Then the path to the file is reconstructed and
> reported as the result.
>
> Because of the VMA walk the code is slightly different on nommu systems.
> This patch avoids separate /proc/pid/exe code on nommu systems. Instead of
> walking the VMAs to find the first executable file-backed VMA we store a
> reference to the exec'd file in the mm_struct.
>
> That reference would prevent the filesystem holding the executable file
> from being unmounted even after unmapping the VMAs. So we track the number
> of VM_EXECUTABLE VMAs and drop the new reference when the last one is
> unmapped. This avoids pinning the mounted filesystem.
exe_file's vma accounting is hooked into every file mmap/unmmap and vma
split/merge just to fix some hypothetical pinning fs from umounting by mm,
which already unmapped all its executable files, but still alive.
Seems like currently nobody depends on this behaviour. We can try to
remove this logic and keep mm->exe_file until final mmput().
mm->exe_file is still protected with mm->mmap_sem, because we want to
change it via new sys_prctl(PR_SET_MM_EXE_FILE). Also via this syscall
task can change its mm->exe_file and unpin mountpoint explicitly.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file
Some security modules and oprofile still uses VM_EXECUTABLE for retrieving
a task's executable file. After this patch they will use mm->exe_file
directly. mm->exe_file is protected with mm->mmap_sem, so locking stays
the same.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [arch/tile] Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [tomoyo] Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Merge VM_INSERTPAGE into VM_MIXEDMAP. VM_MIXEDMAP VMA can mix pure-pfn
ptes, special ptes and normal ptes.
Now copy_page_range() always copies VM_MIXEDMAP VMA on fork like
VM_PFNMAP. If driver populates whole VMA at mmap() it probably not
expects page-faults.
This patch removes special check from vma_wants_writenotify() which
disables pages write tracking for VMA populated via vm_instert_page().
BDI below mapped file should not use dirty-accounting, moreover
do_wp_page() can handle this.
vm_insert_page() still marks vma after first usage. Usually it is called
from f_op->mmap() handler under mm->mmap_sem write-lock, so it able to
change vma->vm_flags. Caller must set VM_MIXEDMAP at mmap time if it
wants to call this function from other places, for example from page-fault
handler.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Replace the generic vma-flag VM_PFN_AT_MMAP with x86-only VM_PAT.
We can toss mapping address from remap_pfn_range() into
track_pfn_vma_new(), and collect all PAT-related logic together in
arch/x86/.
This patch also restores orignal frustration-free is_cow_mapping() check
in remap_pfn_range(), as it was before commit v2.6.28-rc8-88-g3c8bb73
("x86: PAT: store vm_pgoff for all linear_over_vma_region mappings - v3")
is_linear_pfn_mapping() checks can be removed from mm/huge_memory.c,
because it already handled by VM_PFNMAP in VM_NO_THP bit-mask.
[suresh.b.siddha@intel.com: Reset the VM_PAT flag as part of untrack_pfn_vma()] Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
x86, pat: separate the pfn attribute tracking for remap_pfn_range and vm_insert_pfn
With PAT enabled, vm_insert_pfn() looks up the existing pfn memory
attribute and uses it. Expectation is that the driver reserves the memory
attributes for the pfn before calling vm_insert_pfn().
remap_pfn_range() (when called for the whole vma) will setup a new
attribute (based on the prot argument) for the specified pfn range. This
addresses the legacy usage which typically calls remap_pfn_range() with a
desired memory attribute. For ranges smaller than the vma size (which is
typically not the case), remap_pfn_range() will use the existing memory
attribute for the pfn range.
Expose two different API's for these different behaviors.
track_pfn_insert() for tracking the pfn attribute set by vm_insert_pfn()
and track_pfn_remap() for the remap_pfn_range().
This cleanup also prepares the ground for the track/untrack pfn vma routines
to take over the ownership of setting PAT specific vm_flag in the 'vma'.
[khlebnikov@openvz.org: Clear checks in track_pfn_remap()] Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Venkatesh Pallipadi <venki@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When transparent huge pages were introduced, memory compaction and swap
storms were an issue, and the kernel had to be careful to not make THP
allocations cause pageout or compaction.
Now that we have working compaction deferral, kswapd is smart enough to
invoke compaction and the quadratic behaviour around isolate_free_pages
has been fixed, it should be safe to remove __GFP_NO_KSWAPD.
[minchan@kernel.org: Comment fix]
[mgorman@suse.de: Avoid direct reclaim for deferred compaction] Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
While allocating pages using buddy allocator, the compound page is
probably split up to free pages. Under these circumstances, the compound
page should be destroyed by destroy_compound_page(). However, there is a
duplicate check to judge if the page is compound.
Remove the duplicate check since the compound_order() returns 0 when the
page doesn't have PG_head set in destroy_compound_page(). That is to say,
destroy_compound_page() needn't check PageHead().
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[EACCES] Permission denied. An attempt was made to access a file in a way
forbidden by its file access permissions.
[EPERM] Operation not permitted. An attempt was made to perform an operation
limited to processes with appropriate privileges or to the owner of a file
or other resource.
So -EPERM should be returned if capability checks fails.
Strictly speaking this is an API change since the error code user sees is
Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Ian Kent <raven@themaw.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When a file is truncated with truncate()/ftruncate() and then closed,
iversion is not updated. This patch uses ATTR_SIZE flag as an indication
to increment iversion.
Mimi said:
On fput(), i_version is used to detect and flag files that have changed
and need to be re-measured in the IMA measurement policy. When a file
is truncated with truncate()/ftruncate() and then closed, i_version is
not updated. As a result, although the file has changed, it will not be
re-measured and added to the IMA measurement list on subsequent access.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Akinobu Mita [Fri, 28 Sep 2012 00:19:00 +0000 (10:19 +1000)]
drbd: use copy_highpage
Use copy_highpage() to copy from one page to another.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stephen Warren [Fri, 28 Sep 2012 00:19:00 +0000 (10:19 +1000)]
block: partition: msdos: provide UUIDs for partitions
The MSDOS/MBR partition table includes a 32-bit unique ID, often referred
to as the NT disk signature. When combined with a partition number within
the table, this can form a unique ID similar in concept to EFI/GPT's
partition UUID. Constructing and recording this value in struct
partition_meta_info allows MSDOS partitions to be referred to on the
kernel command-line using the following syntax:
Stephen Warren [Fri, 28 Sep 2012 00:19:00 +0000 (10:19 +1000)]
init: reduce PARTUUID min length to 1 from 36
Reduce the minimum length for a root=PARTUUID= parameter to be considered
valid from 36 to 1. EFI/GPT partition UUIDs are always exactly 36
characters long, hence the previous limit. However, the next patch will
support DOS/MBR UUIDs too, which have a different, shorter, format.
Instead of validating any particular length, just ensure that at least
some non-empty value was given by the user.
Also, consider a missing UUID value to be a parsing error, in the same
vein as if /PARTNROFF exists and can't be parsed. As such, make both
error cases print a message and disable rootwait. Convert to pr_err while
we're at it.
Signed-off-by: Stephen Warren <swarren@nvidia.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Will Drewry <wad@chromium.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stephen Warren [Fri, 28 Sep 2012 00:18:59 +0000 (10:18 +1000)]
block: store partition_meta_info.uuid as a string
This will allow other types of UUID to be stored here, aside from true
UUIDs. This also simplifies code that uses this field, since it's usually
constructed from a, used as a, or compared to other, strings.
Note: A simplistic approach here would be to set uuid_str[36]=0 whenever a
/PARTNROFF option was found to be present. However, this modifies the
input string, and causes subsequent calls to devt_from_partuuid() not to
see the /PARTNROFF option, which causes different results. In order to
avoid misleading future maintainers, this parameter is marked const.
Signed-off-by: Stephen Warren <swarren@nvidia.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Will Drewry <wad@chromium.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Akinobu Mita [Fri, 28 Sep 2012 00:18:59 +0000 (10:18 +1000)]
cciss: use check_signature()
Use check_signature() to find a signature in the mmio address.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Mike Miller <mike.miller@hp.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Akinobu Mita [Fri, 28 Sep 2012 00:18:59 +0000 (10:18 +1000)]
cciss: cleanup bitops usage
- Remove unnecessary correction of bit and address
- Use BITS_TO_LONGS macro to calculate bitmap size
- Use bitmap_zero()
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Mike Miller <mike.miller@hp.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Martin Michlmayr [Fri, 28 Sep 2012 00:18:58 +0000 (10:18 +1000)]
drivers/scsi/atp870u.c: fix bad use of udelay
The ACARD driver calls udelay() with a value > 2000, which leads to
to the following compilation error on ARM:
ERROR: "__bad_udelay" [drivers/scsi/atp870u.ko] undefined!
make[1]: *** [__modpost] Error 1
This is because udelay is defined on ARM, roughly speaking, as
The argument to __const_udelay is the number of jiffies to wait divided by
4, but this does not work unless the multiplication does not overflow, and
that is what the build error is designed to prevent. The intended
behavior can be achieved by using mdelay to call udelay multiple times in
a loop.
[jn: adding context] Signed-off-by: Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Shaohua Li [Fri, 28 Sep 2012 00:18:58 +0000 (10:18 +1000)]
readahead: fault retry breaks mmap file read random detection
.fault now can retry. The retry can break state machine of .fault. In
filemap_fault, if page is miss, ra->mmap_miss is increased. In the second
try, since the page is in page cache now, ra->mmap_miss is decreased. And
these are done in one fault, so we can't detect random mmap file access.
Add a new flag to indicate .fault is tried once. In the second try, skip
ra->mmap_miss decreasing. The filemap_fault state machine is ok with it.
I only tested x86, didn't test other archs, but looks the change for other
archs is obvious, but who knows :)
Signed-off-by: Shaohua Li <shaohua.li@fusionio.com> Cc: Rik van Riel <riel@redhat.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix multicast packet transmit logic to account for repetitive transmission
of single skb:
- correct check for available buffers (this bug may produce NULL pointer
crash dump in case of heavy traffic);
- update skb user count (incorrect user counter causes a warning dump from
net_tx_action routine during multicast transfers in systems with three or
more rionet participants).
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: David S. Miller <davem@davemloft.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The block control group, infiniband, xfs, crypto, 802.11, netfilter.
Nothing quite so fundamental as fs/namespace.c but definitely in
multiplatform-code that should work, and is already broken on those
architecutres.
Looking at the implementation of atomic64_add_return in lib/atomic64.c the
code looks as efficient as these kinds of things get.
Which leads me to the conclusion that we need atomic64 support on all
architectures.
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Daniel Santos [Fri, 28 Sep 2012 00:18:55 +0000 (10:18 +1000)]
compiler-gcc4.h: correct verion check for __compiletime_error
__attribute__((error(msg))) was introduced in gcc 4.3 (not 4.4) and as I
was unable to find any gcc bugs pertaining to it, I'm presuming that it
has functioned as advertised since 4.3.0.
Signed-off-by: Daniel Santos <daniel.santos@pobox.com> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
kbuild: make: fix if_changed when command contains backslashes
The call if_changed mechanism does not work when the command
contains backslashes. This basically is an issue with lzo
and bzip2 compressed kernels. The compressed binaries do not
contain the uncompressed image size, so these use size_append
to append the size. This results in backslashes in the executed
command. With this if_changed always detects a change in the
command and rebuilds the compressed image even if nothing
has changed.
Fix this by escaping backslashes in make-cmd
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Jan Luebbe <jlu@pengutronix.de> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Bernhard Walle <bernhard@bwalle.de> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
How is the compiler even handling exported functions that are marked
inline? Anyway, these shouldn't be inline because of that, so remove that
marking.
Based on a larger patch by Mark Charlebois to get LLVM to build the
kernel.
Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Charlebois <mcharleb@qualcomm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: hank <pyu@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The use of defined() on arrays and hashes has been deprecated since perl
5.6, but until 5.17.6 it only warned on lexicals, not package globals.
Signed-off-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jean Delvare [Fri, 28 Sep 2012 00:18:54 +0000 (10:18 +1000)]
drm/i915: optimize DIV_ROUND_CLOSEST() call
DIV_ROUND_CLOSEST is faster if the compiler knows it will only be dealing
with unsigned dividends.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pcmcia: move unbind/rebind into dev_pm_ops.complete
Move the device rebind procedures for cardbus devices from the pm.resume
into the pm.complete callback.
The reason for moving the code is: "[...] The PM code needs to send
suspend and resume messages to every device in the right order, and it
can't do that if new devices are being added at the same time. [...]"
However the situation really isn't quite that rigid. In particular,
adding new children during a resume callback shouldn't cause much of
problem because the children don't need to be resumed anyway (since they
were never suspended). On the other hand, if you do it you will get a
dev_warn() from the PM core, something like 'parent should not be
sleeping'.
Still, it is considered bad form and should be avoided if possible."
(Alan Stern's full comment about the topic can
be found here: <https://lkml.org/lkml/2012/7/10/254>)
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Greg KH <greg@kroah.com> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
drivers/dma/dmaengine.c: lower the priority of 'failed to get' dma channel message
Do the same as commit a03a202e9 ("dmaengine: failure to get a specific DMA
channel is not critical") to get rid of the following messages during
kernel boot:
dmaengine_get: failed to get dma1chan0: (-22)
dmaengine_get: failed to get dma1chan1: (-22)
dmaengine_get: failed to get dma1chan2: (-22)
dmaengine_get: failed to get dma1chan3: (-22)
dmaengine_get: failed to get dma1chan4: (-22)
dmaengine_get: failed to get dma1chan5: (-22)
dmaengine_get: failed to get dma1chan6: (-22)
dmaengine_get: failed to get dma1chan7: (-22)
dmaengine_get: failed to get dma1chan8: (-22)
dmaengine_get: failed to get dma1chan9: (-22)
dmaengine_get: failed to get dma1chan10: (-22)
dmaengine_get: failed to get dma1chan11: (-22)
dmaengine_get: failed to get dma1chan12: (-22)
dmaengine_get: failed to get dma1chan13: (-22)
dmaengine_get: failed to get dma1chan14: (-22)
dmaengine_get: failed to get dma1chan15: (-22)
dmaengine_get: failed to get dma1chan16: (-22)
dmaengine_get: failed to get dma1chan17: (-22)
dmaengine_get: failed to get dma1chan18: (-22)
dmaengine_get: failed to get dma1chan19: (-22)
dmaengine_get: failed to get dma1chan20: (-22)
dmaengine_get: failed to get dma1chan21: (-22)
dmaengine_get: failed to get dma1chan22: (-22)
dmaengine_get: failed to get dma1chan23: (-22)
dmaengine_get: failed to get dma1chan24: (-22)
dmaengine_get: failed to get dma1chan25: (-22)
dmaengine_get: failed to get dma1chan26: (-22)
dmaengine_get: failed to get dma1chan27: (-22)
dmaengine_get: failed to get dma1chan28: (-22)
dmaengine_get: failed to get dma1chan29: (-22)
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Alex Shi [Fri, 28 Sep 2012 00:18:51 +0000 (10:18 +1000)]
arch/x86/platform/uv: fix incorrect tlb flush all issue
The flush tlb optimization code has logical issue on UV platform. It
doesn't flush the full range at all, since it simply ignores its 'end'
parameter (and hence also the "all" indicator) in uv_flush_tlb_others()
function.
Cliff's notes:
: I tested the patch on a UV. It has the effect of either clearing 1 or all
: TLBs in a cpu. I added some debugging to test for the cases when clearing
: all TLBs is overkill, and in practice it happens very seldom.
Reported-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Cliff Wickman <cpw@sgi.com> Tested-by: Cliff Wickman <cpw@sgi.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andrew Morton [Fri, 28 Sep 2012 00:18:51 +0000 (10:18 +1000)]
arch/x86/tools/insn_sanity.c: identify source of messages
The kernel build prints:
Building modules, stage 2.
TEST posttest
MODPOST 3821 modules
TEST posttest
Success: decoded and checked 1000000 random instructions with 0 errors (seed:0xaac4bc47)
CC arch/x86/boot/a20.o
CC arch/x86/boot/cmdline.o
AS arch/x86/boot/copy.o
HOSTCC arch/x86/boot/mkcpustr
CC arch/x86/boot/cpucheck.o
CC arch/x86/boot/early_serial_console.o
which is irritating because you don't know what program is proudly
pronouncing its success.
So, as described in "console mode programming user interface guidelines
version 101" which doesn't exist, change this program to identify the
source of its messages.
Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If we aren't debugging per_cpu maps, the cpu's node is stored in per_cpu
variable numa_node. If `node' is NUMA_NO_NODE, it means the caller wants
to clear the cpu's node. So we should also call set_cpu_numa_node() in
this case.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
acpi_memhotplug.c: auto bind the memory device which is hotplugged before the driver is loaded
If the memory device is hotplugged before the driver is loaded, the user
cannot see this device under the directory /sys/bus/acpi/devices/, and the
user cannot bind it by hand after the driver is loaded. This patch
introduces a new feature to bind such device when the driver is being
loaded.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Len Brown <lenb@kernel.org> Cc: "Brown, Len" <len.brown@intel.com> Cc: Yasuaki ISIMATU <isimatu.yasuaki@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
acpi_memhotplug.c: bind the memory device when the driver is being loaded
We had introduced acpi_hotmem_initialized to avoid strange add_memory fail
message. But the memory device may not be used by the kernel, and the
device should be bound when the driver is being loaded. Remove
acpi_hotmem_initialized to allow that the device can be bound when the
driver is being loaded.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Len Brown <lenb@kernel.org> Cc: "Brown, Len" <len.brown@intel.com> Cc: Yasuaki ISIMATU <isimatu.yasuaki@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
acpi_memhotplug.c: free memory device if acpi_memory_enable_device() failed
If acpi_memory_enable_device() fails, acpi_memory_enable_device() will
return a non-zero value, which means we fail to bind the memory device to
this driver. So we should free memory device before
acpi_memory_device_add() returns.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Len Brown <lenb@kernel.org> Cc: "Brown, Len" <len.brown@intel.com> Cc: Yasuaki ISIMATU <isimatu.yasuaki@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
x86 cpu_hotplug: unmap cpu2node when the cpu is hotremoved
When a cpu is hotplugged, we call acpi_map_cpu2node() in
_acpi_map_lsapic() to store the cpu's node. But we don't clear the cpu's
node in acpi_unmap_lsapic() when this cpu is hotremoved. If the node is
also hotremoved, We will get the following messages:
The reason is that: the cpu's node is not NUMA_NO_NODE, we will call
alloc_pages_exact_node() to alloc memory on the node, but the node is
offlined.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
vfs: d_obtain_alias() needs to use "/" as default name.
NFS appears to use d_obtain_alias() to create the root dentry rather than
d_make_root. This can cause 'prepend_path()' to complain that the root
has a weird name if an NFS filesystem is lazily unmounted. e.g. if
"/mnt" is an NFS mount then
{ cd /mnt; umount -l /mnt ; ls -l /proc/self/cwd; }
will cause a WARN message like
WARNING: at /home/git/linux/fs/dcache.c:2624 prepend_path+0x1d7/0x1e0()
...
Root dentry has weird name <>
to appear in kernel logs.
So change d_obtain_alias() to use "/" rather than "" as the anonymous
name.
Signed-off-by: NeilBrown <neilb@suse.de> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This patch below does what Paul McKenney suggested in the previous thread.
Signed-off-by: Dave Jones <davej@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Paul Moore <paul@paul-moore.com> Cc: Eric Paris <eparis@parisplace.org> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The inb/outb macros for CRIS are broken from a number of points of view,
missing () around parameters and they have an unprotected if statement in
them. This was breaking the compile of IPMI on CRIS and thus I was being
annoyed by build regressions, so I fixed them.
Plus I don't think they would have worked at all, since the data values
were missing "&" and the outsl had a "3" instead of a "4" for the size.
From what I can tell, this stuff is not used at all, so this can't be any
more broken than it was before, anyway.
Signed-off-by: Corey Minyard <cminyard@mvista.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Mikael Starvik <starvik@axis.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log