1. 11 May, 2008 3 commits
    • Linus Torvalds's avatar
      Revert "semaphore: fix" · 00b41ec2
      Linus Torvalds authored
      This reverts commit bf726eab, as it has
      been reported to cause a regression with processes stuck in __down(),
      apparently because some missing wakeup.
      
      Quoth Sven Wegener:
       "I'm currently investigating a regression that has showed up with my
        last git pull yesterday.  Bisecting the commits showed bf726e
        "semaphore: fix" to be the culprit, reverting it fixed the issue.
      
        Symptoms: During heavy filesystem usage (e.g.  a kernel compile) I get
        several compiler processes in uninterruptible sleep, blocking all i/o
        on the filesystem.  System is an Intel Core 2 Quad running a 64bit
        kernel and userspace.  Filesystem is xfs on top of lvm.  See below for
        the output of sysrq-w."
      
      See
      
      	http://lkml.org/lkml/2008/5/10/45
      
      for full report.
      
      In the meantime, we can just fix the BKL performance regression by
      reverting back to the good old BKL spinlock implementation instead,
      since any sleeping lock will generally perform badly, especially if it
      tries to be fair.
      Reported-by: default avatarSven Wegener <sven.wegener@stealer.net>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      00b41ec2
    • Linus Torvalds's avatar
      Make <asm-x86/spinlock.h> use ACCESS_ONCE() · 39f004ba
      Linus Torvalds authored
      ..instead of cooking up its own uglier local version of it.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      39f004ba
    • Linus Torvalds's avatar
      Move ACCESS_ONCE() to <linux/compiler.h> · 9c3cdc1f
      Linus Torvalds authored
      It actually makes much more sense there, and we do tend to need it for
      non-RCU usage too.  Moving it to <linux/compiler.h> will allow some
      other cases that have open-coded the same logic to use the same helper
      function that RCU has used.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9c3cdc1f
  2. 09 May, 2008 28 commits
  3. 08 May, 2008 9 commits