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  1. 03 12月, 2010 14 次提交
  3. 02 12月, 2010 13 次提交
  5. 01 12月, 2010 13 次提交
    • D
      xfs: only run xfs_error_test if error injection is active · c76febef
      由 Dave Chinner 提交于 
      Recent tests writing lots of small files showed the flusher thread
being CPU bound and taking a long time to do allocations on a debug
kernel. perf showed this as the prime reason:

             samples  pcnt function                    DSO
             _______ _____ ___________________________ _________________

           224648.00 36.8% xfs_error_test              [kernel.kallsyms]
            86045.00 14.1% xfs_btree_check_sblock      [kernel.kallsyms]
            39778.00  6.5% prandom32                   [kernel.kallsyms]
            37436.00  6.1% xfs_btree_increment         [kernel.kallsyms]
            29278.00  4.8% xfs_btree_get_rec           [kernel.kallsyms]
            27717.00  4.5% random32                    [kernel.kallsyms]

Walking btree blocks during allocation checking them requires each
block (a cache hit, so no I/O) call xfs_error_test(), which then
does a random32() call as the first operation.  IOWs, ~50% of the
CPU is being consumed just testing whether we need to inject an
error, even though error injection is not active.

Kill this overhead when error injection is not active by adding a
global counter of active error traps and only calling into
xfs_error_test when fault injection is active.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      c76febef
    • D
      xfs: avoid moving stale inodes in the AIL · de25c181
      由 Dave Chinner 提交于 
      When an inode has been marked stale because the cluster is being
freed, we don't want to (re-)insert this inode into the AIL. There
is a race condition where the cluster buffer may be unpinned before
the inode is inserted into the AIL during transaction committed
processing. If the buffer is unpinned before the inode item has been
committed and inserted, then it is possible for the buffer to be
released and hence processthe stale inode callbacks before the inode
is inserted into the AIL.

In this case, we then insert a clean, stale inode into the AIL which
will never get removed by an IO completion. It will, however, get
reclaimed and that triggers an assert in xfs_inode_free()
complaining about freeing an inode still in the AIL.

This race can be avoided by not moving stale inodes forward in the AIL
during transaction commit completion processing. This closes the
race condition by ensuring we never insert clean stale inodes into
the AIL. It is safe to do this because a dirty stale inode, by
definition, must already be in the AIL.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      de25c181
    • D
      xfs: delayed alloc blocks beyond EOF are valid after writeback · 309c8480
      由 Dave Chinner 提交于 
      There is an assumption in the parts of XFS that flushing a dirty
file will make all the delayed allocation blocks disappear from an
inode. That is, that after calling xfs_flush_pages() then
ip->i_delayed_blks will be zero.

This is an invalid assumption as we may have specualtive
preallocation beyond EOF and they are recorded in
ip->i_delayed_blks. A flush of the dirty pages of an inode will not
change the state of these blocks beyond EOF, so a non-zero
deeelalloc block count after a flush is valid.

The bmap code has an invalid ASSERT() that needs to be removed, and
the swapext code has a bug in that while it swaps the data forks
around, it fails to swap the i_delayed_blks counter associated with
the fork and hence can get the block accounting wrong.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      309c8480
    • D
      xfs: push stale, pinned buffers on trylock failures · 90810b9e
      由 Dave Chinner 提交于 
      As reported by Nick Piggin, XFS is suffering from long pauses under
highly concurrent workloads when hosted on ramdisks. The problem is
that an inode buffer is stuck in the pinned state in memory and as a
result either the inode buffer or one of the inodes within the
buffer is stopping the tail of the log from being moved forward.

The system remains in this state until a periodic log force issued
by xfssyncd causes the buffer to be unpinned. The main problem is
that these are stale buffers, and are hence held locked until the
transaction/checkpoint that marked them state has been committed to
disk. When the filesystem gets into this state, only the xfssyncd
can cause the async transactions to be committed to disk and hence
unpin the inode buffer.

This problem was encountered when scaling the busy extent list, but
only the blocking lock interface was fixed to solve the problem.
Extend the same fix to the buffer trylock operations - if we fail to
lock a pinned, stale buffer, then force the log immediately so that
when the next attempt to lock it comes around, it will have been
unpinned.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      90810b9e
    • D
      xfs: fix failed write truncation handling. · c726de44
      由 Dave Chinner 提交于 
      Since the move to the new truncate sequence we call xfs_setattr to
truncate down excessively instanciated blocks.  As shown by the testcase
in kernel.org BZ #22452 that doesn't work too well.  Due to the confusion
of the internal inode size, and the VFS inode i_size it zeroes data that
it shouldn't.

But full blown truncate seems like overkill here.  We only instanciate
delayed allocations in the write path, and given that we never released
the iolock we can't have converted them to real allocations yet either.

The only nasty case is pre-existing preallocation which we need to skip.
We already do this for page discard during writeback, so make the delayed
allocation block punching a generic function and call it from the failed
write path as well as xfs_aops_discard_page. The callers are
responsible for ensuring that partial blocks are not truncated away,
and that they hold the ilock.

Based on a fix originally from Christoph Hellwig. This version used
filesystem blocks as the range unit.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      c726de44
    • L
      Merge branch 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 · fb82155d
      由 Linus Torvalds 提交于 
      * 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms: add workaround for dce3 ddc line vbios bug
  drm/radeon/kms: fix interlaced and doublescan handling
  drm/radeon/kms: fix typos in disabled vbios code
  Revert "drm/i915/dp: use VBT provided eDP params if available"
  drm/i915: Clear pfit registers when not used by any outputs
  drm: record monitor status in output_poll_execute
  drm: Set connector DPMS status to ON in drm_crtc_helper_set_config
  drm/i915: fix regression due to ba3d8d74
  Revert "drm/radeon/kms: fix typo in r600 cs checker"
  drm/i915/sdvo: Always add a 30ms delay to make SDVO TV detection reliable
  MAINTAINERS: INTEL DRM DRIVERS list (intel-gfx) is subscribers-only
  drm/i915/sdvo: Always fallback to querying the shared DDC line
  drm/i915: Handle pagefaults in execbuffer user relocations
  drm/i915/sdvo: Only enable HDMI encodings only if the commandset is supported
  drm/radeon/kms: fix resume regression for some r5xx laptops
  drm/radeon/kms: fix regression in rs4xx i2c setup
  drm/i915: Only save/restore cursor regs if !KMS
  drm/i915: Prevent integer overflow when validating the execbuffer
      fb82155d
    • A
      drm/radeon/kms: add workaround for dce3 ddc line vbios bug · 3074adc8
      由 Alex Deucher 提交于 
      fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=23752Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc:stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>
      3074adc8
    • A
      drm/radeon/kms: fix interlaced and doublescan handling · c49948f4
      由 Alex Deucher 提交于 
      Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>
      c49948f4
    • A
      drm/radeon/kms: fix typos in disabled vbios code · 0ec80d64
      由 Alex Deucher 提交于 
      6xx/7xx was hitting the wrong BUS_CNTL reg and bits.
Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>
      0ec80d64
    • D
      Merge remote branch 'intel/drm-intel-fixes' of /ssd/git/drm-next into drm-fixes · 150f8815
      由 Dave Airlie 提交于 
      * 'intel/drm-intel-fixes' of /ssd/git/drm-next:
  Revert "drm/i915/dp: use VBT provided eDP params if available"
  drm/i915: Clear pfit registers when not used by any outputs
  drm/i915: fix regression due to ba3d8d74
      150f8815
    • L
      Merge branch 'for_linus' of git://github.com/at91linux/linux-2.6-at91 · 22a5b566
      由 Linus Torvalds 提交于 
      * 'for_linus' of git://github.com/at91linux/linux-2.6-at91:
  at91/board-yl-9200: fix typo in video support
  atmel_spi: fix warning In function 'atmel_spi_dma_map_xfer'
  at91/picotux200: remove commenting usb device and dataflash support
  at91: rename rm9200ek and rm9200dk board file name
  at91rm9200ek: fix warning: 'ek_mmc_data' defined but not used
  at91rm9200dk: fix warning: 'dk_mmc_data' defined but not used
  at91: Convert remaining boards to new-style UART initialization
  at91: merge all at91rm9200 defconfig in one single file
      22a5b566
    • O
      exec: copy-and-paste the fixes into compat_do_execve() paths · 114279be
      由 Oleg Nesterov 提交于 
      Note: this patch targets 2.6.37 and tries to be as simple as possible.
That is why it adds more copy-and-paste horror into fs/compat.c and
uglifies fs/exec.c, this will be cleanuped later.

compat_copy_strings() plays with bprm->vma/mm directly and thus has
two problems: it lacks the RLIMIT_STACK check and argv/envp memory
is not visible to oom killer.

Export acct_arg_size() and get_arg_page(), change compat_copy_strings()
to use get_arg_page(), change compat_do_execve() to do acct_arg_size(0)
as do_execve() does.

Add the fatal_signal_pending/cond_resched checks into compat_count() and
compat_copy_strings(), this matches the code in fs/exec.c and certainly
makes sense.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      114279be
    • O
      exec: make argv/envp memory visible to oom-killer · 3c77f845
      由 Oleg Nesterov 提交于 
      Brad Spengler published a local memory-allocation DoS that
evades the OOM-killer (though not the virtual memory RLIMIT):
http://www.grsecurity.net/~spender/64bit_dos.c

execve()->copy_strings() can allocate a lot of memory, but
this is not visible to oom-killer, nobody can see the nascent
bprm->mm and take it into account.

With this patch get_arg_page() increments current's MM_ANONPAGES
counter every time we allocate the new page for argv/envp. When
do_execve() succeds or fails, we change this counter back.

Technically this is not 100% correct, we can't know if the new
page is swapped out and turn MM_ANONPAGES into MM_SWAPENTS, but
I don't think this really matters and everything becomes correct
once exec changes ->mm or fails.
Reported-by: NBrad Spengler <spender@grsecurity.net>
Reviewed-and-discussed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3c77f845