1. 19 10月, 2010 10 次提交
    • D
      xfs: don't use vfs writeback for pure metadata modifications · dcd79a14
      Dave Chinner 提交于
      Under heavy multi-way parallel create workloads, the VFS struggles
      to write back all the inodes that have been changed in age order.
      The bdi flusher thread becomes CPU bound, spending 85% of it's time
      in the VFS code, mostly traversing the superblock dirty inode list
      to separate dirty inodes old enough to flush.
      
      We already keep an index of all metadata changes in age order - in
      the AIL - and continued log pressure will do age ordered writeback
      without any extra overhead at all. If there is no pressure on the
      log, the xfssyncd will periodically write back metadata in ascending
      disk address offset order so will be very efficient.
      
      Hence we can stop marking VFS inodes dirty during transaction commit
      or when changing timestamps during transactions. This will keep the
      inodes in the superblock dirty list to those containing data or
      unlogged metadata changes.
      
      However, the timstamp changes are slightly more complex than this -
      there are a couple of places that do unlogged updates of the
      timestamps, and the VFS need to be informed of these. Hence add a
      new function xfs_trans_ichgtime() for transactional changes,
      and leave xfs_ichgtime() for the non-transactional changes.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NAlex Elder <aelder@sgi.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      dcd79a14
    • D
      xfs: lockless per-ag lookups · e176579e
      Dave Chinner 提交于
      When we start taking a reference to the per-ag for every cached
      buffer in the system, kernel lockstat profiling on an 8-way create
      workload shows the mp->m_perag_lock has higher acquisition rates
      than the inode lock and has significantly more contention. That is,
      it becomes the highest contended lock in the system.
      
      The perag lookup is trivial to convert to lock-less RCU lookups
      because perag structures never go away. Hence the only thing we need
      to protect against is tree structure changes during a grow. This can
      be done simply by replacing the locking in xfs_perag_get() with RCU
      read locking. This removes the mp->m_perag_lock completely from this
      path.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Reviewed-by: NAlex Elder <aelder@sgi.com>
      e176579e
    • D
      xfs: remove debug assert for per-ag reference counting · bd32d25a
      Dave Chinner 提交于
      When we start taking references per cached buffer to the the perag
      it is cached on, it will blow the current debug maximum reference
      count assert out of the water. The assert has never caught a bug,
      and we have tracing to track changes if there ever is a problem,
      so just remove it.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Reviewed-by: NAlex Elder <aelder@sgi.com>
      bd32d25a
    • D
      xfs: reduce the number of CIL lock round trips during commit · d1583a38
      Dave Chinner 提交于
      When commiting a transaction, we do a lock CIL state lock round trip
      on every single log vector we insert into the CIL. This is resulting
      in the lock being as hot as the inode and dcache locks on 8-way
      create workloads. Rework the insertion loops to bring the number
      of lock round trips to one per transaction for log vectors, and one
      more do the busy extents.
      
      Also change the allocation of the log vector buffer not to zero it
      as we copy over the entire allocated buffer anyway.
      
      This patch also includes a structural cleanup to the CIL item
      insertion provided by Christoph Hellwig.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Reviewed-by: NAlex Elder <aelder@sgi.com>
      d1583a38
    • P
      xfs: eliminate some newly-reported gcc warnings · 9c169915
      Poyo VL 提交于
      Ionut Gabriel Popescu <poyo_vl@yahoo.com> submitted a simple change
      to eliminate some "may be used uninitialized" warnings when building
      XFS.  The reported condition seems to be something that GCC did not
      used to recognize or report.  The warnings were produced by:
      
          gcc version 4.5.0 20100604
          [gcc-4_5-branch revision 160292] (SUSE Linux)
      Signed-off-by: NIonut Gabriel Popescu <poyo_vl@yahoo.com>
      Signed-off-by: NAlex Elder <aelder@sgi.com>
      9c169915
    • C
      xfs: remove the ->kill_root btree operation · c0e59e1a
      Christoph Hellwig 提交于
      The implementation os ->kill_root only differ by either simply
      zeroing out the now unused buffer in the btree cursor in the inode
      allocation btree or using xfs_btree_setbuf in the allocation btree.
      
      Initially both of them used xfs_btree_setbuf, but the use in the
      ialloc btree was removed early on because it interacted badly with
      xfs_trans_binval.
      
      In addition to zeroing out the buffer in the cursor xfs_btree_setbuf
      updates the bc_ra array in the btree cursor, and calls
      xfs_trans_brelse on the buffer previous occupying the slot.
      
      The bc_ra update should be done for the alloc btree updated too,
      although the lack of it does not cause serious problems.  The
      xfs_trans_brelse call on the other hand is effectively a no-op in
      the end - it keeps decrementing the bli_recur refcount until it hits
      zero, and then just skips out because the buffer will always be
      dirty at this point.  So removing it for the allocation btree is
      just fine.
      
      So unify the code and move it to xfs_btree.c.  While we're at it
      also replace the call to xfs_btree_setbuf with a NULL bp argument in
      xfs_btree_del_cursor with a direct call to xfs_trans_brelse given
      that the cursor is beeing freed just after this and the state
      updates are superflous.  After this xfs_btree_setbuf is only used
      with a non-NULL bp argument and can thus be simplified.
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NAlex Elder <aelder@sgi.com>
      c0e59e1a
    • C
      xfs: stop using xfs_qm_dqtobp in xfs_qm_dqflush · acecf1b5
      Christoph Hellwig 提交于
      In xfs_qm_dqflush we know that q_blkno must be initialized already from a
      previous xfs_qm_dqread.  So instead of calling xfs_qm_dqtobp we can
      simply read the quota buffer directly.  This also saves us from a duplicate
      xfs_qm_dqcheck call check and allows xfs_qm_dqtobp to be simplified now
      that it is always called for a newly initialized inode.  In addition to
      that properly unwind all locks in xfs_qm_dqflush when xfs_qm_dqcheck
      fails.
      
      This mirrors a similar cleanup in the inode lookup done earlier.
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NAlex Elder <aelder@sgi.com>
      acecf1b5
    • C
      xfs: simplify xfs_qm_dqusage_adjust · 52fda114
      Christoph Hellwig 提交于
      There is no need to have the users and group/project quota locked at the
      same time.  Get rid of xfs_qm_dqget_noattach and just do a xfs_qm_dqget
      inside xfs_qm_quotacheck_dqadjust for the quota we are operating on
      right now.  The new version of xfs_qm_quotacheck_dqadjust holds the
      inode lock over it's operations, which is not a problem as it simply
      increments counters and there is no concern about log contention
      during mount time.
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NAlex Elder <aelder@sgi.com>
      52fda114
    • D
      xfs: Introduce XFS_IOC_ZERO_RANGE · 44722352
      Dave Chinner 提交于
      XFS_IOC_ZERO_RANGE is the equivalent of an atomic XFS_IOC_UNRESVSP/
      XFS_IOC_RESVSP call pair. It enabled ranges of written data to be
      turned into zeroes without requiring IO or having to free and
      reallocate the extents in the range given as would occur if we had
      to punch and then preallocate them separately.  This enables
      applications to zero parts of files very quickly without changing
      the layout of the files in any way.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      44722352
    • D
      xfs: use range primitives for xfs page cache operations · 3ae4c9de
      Dave Chinner 提交于
      While XFS passes ranges to operate on from the core code, the
      functions being called ignore the either the entire range or the end
      of the range. This is historical because when the function were
      written linux didn't have the necessary range operations. Update the
      functions to use the correct operations.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      3ae4c9de
  2. 15 10月, 2010 4 次提交
    • L
      Linux 2.6.36-rc8 · cd07202c
      Linus Torvalds 提交于
      cd07202c
    • L
      Un-inline the core-dump helper functions · 3aa0ce82
      Linus Torvalds 提交于
      Tony Luck reports that the addition of the access_ok() check in commit
      0eead9ab ("Don't dump task struct in a.out core-dumps") broke the
      ia64 compile due to missing the necessary header file includes.
      
      Rather than add yet another include (<asm/unistd.h>) to make everything
      happy, just uninline the silly core dump helper functions and move the
      bodies to fs/exec.c where they make a lot more sense.
      
      dump_seek() in particular was too big to be an inline function anyway,
      and none of them are in any way performance-critical.  And we really
      don't need to mess up our include file headers more than they already
      are.
      Reported-and-tested-by: NTony Luck <tony.luck@gmail.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3aa0ce82
    • L
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 · ae42d8d4
      Linus Torvalds 提交于
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
        ehea: Fix a checksum issue on the receive path
        net: allow FEC driver to use fixed PHY support
        tg3: restore rx_dropped accounting
        b44: fix carrier detection on bind
        net: clear heap allocations for privileged ethtool actions
        NET: wimax, fix use after free
        ATM: iphase, remove sleep-inside-atomic
        ATM: mpc, fix use after free
        ATM: solos-pci, remove use after free
        net/fec: carrier off initially to avoid root mount failure
        r8169: use device model DMA API
        r8169: allocate with GFP_KERNEL flag when able to sleep
      ae42d8d4
    • L
      Don't dump task struct in a.out core-dumps · 0eead9ab
      Linus Torvalds 提交于
      akiphie points out that a.out core-dumps have that odd task struct
      dumping that was never used and was never really a good idea (it goes
      back into the mists of history, probably the original core-dumping
      code).  Just remove it.
      
      Also do the access_ok() check on dump_write().  It probably doesn't
      matter (since normal filesystems all seem to do it anyway), but he
      points out that it's normally done by the VFS layer, so ...
      
      [ I suspect that we should possibly do "vfs_write()" instead of
        calling ->write directly.  That also does the whole fsnotify and write
        statistics thing, which may or may not be a good idea. ]
      
      And just to be anal, do this all for the x86-64 32-bit a.out emulation
      code too, even though it's not enabled (and won't currently even
      compile)
      Reported-by: Nakiphie <akiphie@lavabit.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0eead9ab
  3. 14 10月, 2010 11 次提交
  4. 13 10月, 2010 5 次提交
    • R
      ARM: relax ioremap prohibition (309caa9c) for -final and -stable · 06c10884
      Russell King 提交于
      ... but produce a big warning about the problem as encouragement
      for people to fix their drivers.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      06c10884
    • R
    • M
      ARM: 6440/1: ep93xx: DMA: fix channel_disable · 10d48b39
      Mika Westerberg 提交于
      When channel_disable() is called, it disables per channel interrupts and
      waits until channels state becomes STATE_STALL, and then disables the
      channel. Now, if the DMA transfer is disabled while the channel is in
      STATE_NEXT we will not wait anything and disable the channel immediately.
      This seems to cause weird data corruption for example in audio transfers.
      
      Fix is to wait while we are in STATE_NEXT or STATE_ON and only then
      disable the channel.
      Signed-off-by: NMika Westerberg <mika.westerberg@iki.fi>
      Acked-by: NRyan Mallon <ryan@bluewatersys.com>
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      10d48b39
    • L
      Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm · 0acc1b2a
      Linus Torvalds 提交于
      * 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
        KVM: x86: Move TSC reset out of vmcb_init
        KVM: x86: Fix SVM VMCB reset
      0acc1b2a
    • S
      ring-buffer: Fix typo of time extends per page · d0134324
      Steven Rostedt 提交于
      Time stamps for the ring buffer are created by the difference between
      two events. Each page of the ring buffer holds a full 64 bit timestamp.
      Each event has a 27 bit delta stamp from the last event. The unit of time
      is nanoseconds, so 27 bits can hold ~134 milliseconds. If two events
      happen more than 134 milliseconds apart, a time extend is inserted
      to add more bits for the delta. The time extend has 59 bits, which
      is good for ~18 years.
      
      Currently the time extend is committed separately from the event.
      If an event is discarded before it is committed, due to filtering,
      the time extend still exists. If all events are being filtered, then
      after ~134 milliseconds a new time extend will be added to the buffer.
      
      This can only happen till the end of the page. Since each page holds
      a full timestamp, there is no reason to add a time extend to the
      beginning of a page. Time extends can only fill a page that has actual
      data at the beginning, so there is no fear that time extends will fill
      more than a page without any data.
      
      When reading an event, a loop is made to skip over time extends
      since they are only used to maintain the time stamp and are never
      given to the caller. As a paranoid check to prevent the loop running
      forever, with the knowledge that time extends may only fill a page,
      a check is made that tests the iteration of the loop, and if the
      iteration is more than the number of time extends that can fit in a page
      a warning is printed and the ring buffer is disabled (all of ftrace
      is also disabled with it).
      
      There is another event type that is called a TIMESTAMP which can
      hold 64 bits of data in the theoretical case that two events happen
      18 years apart. This code has not been implemented, but the name
      of this event exists, as well as the structure for it. The
      size of a TIMESTAMP is 16 bytes, where as a time extend is only
      8 bytes. The macro used to calculate how many time extends can fit on
      a page used the TIMESTAMP size instead of the time extend size
      cutting the amount in half.
      
      The following test case can easily trigger the warning since we only
      need to have half the page filled with time extends to trigger the
      warning:
      
       # cd /sys/kernel/debug/tracing/
       # echo function > current_tracer
       # echo 'common_pid < 0' > events/ftrace/function/filter
       # echo > trace
       # echo 1 > trace_marker
       # sleep 120
       # cat trace
      
      Enabling the function tracer and then setting the filter to only trace
      functions where the process id is negative (no events), then clearing
      the trace buffer to ensure that we have nothing in the buffer,
      then write to trace_marker to add an event to the beginning of a page,
      sleep for 2 minutes (only 35 seconds is probably needed, but this
      guarantees the bug), and then finally reading the trace which will
      trigger the bug.
      
      This patch fixes the typo and prevents the false positive of that warning.
      Reported-by: NHans J. Koch <hjk@linutronix.de>
      Tested-by: NHans J. Koch <hjk@linutronix.de>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Stable Kernel <stable@kernel.org>
      Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      d0134324
  5. 12 10月, 2010 10 次提交