1. 20 6月, 2008 1 次提交
  2. 19 6月, 2008 1 次提交
    • L
      x86, bitops: make constant-bit set/clear_bit ops faster · 1a750e0c
      Linus Torvalds 提交于
      On Wed, 18 Jun 2008, Linus Torvalds wrote:
      >
      > And yes, the "lock andl" should be noticeably faster than the xchgl.
      
      I dunno. Here's a untested (!!) patch that turns constant-bit
      set/clear_bit ops into byte mask ops (lock orb/andb).
      
      It's not exactly pretty. The reason for using the byte versions is that a
      locked op is serialized in the memory pipeline anyway, so there are no
      forwarding issues (that could slow down things when we access things with
      different sizes), and the byte ops are a lot smaller than 32-bit and
      particularly 64-bit ops (big constants, and the 64-bit ops need the REX
      prefix byte too).
      
      [ Side note: I wonder if we should turn the "test_bit()" C version into a
        "char *" version too.. It could actually help with alias analysis, since
        char pointers can alias anything. So it might be the RightThing(tm) to
        do for multiple reasons. I dunno. It's a separate issue. ]
      
      It does actually shrink the kernel image a bit (a couple of hundred bytes
      on the text segment for my everything-compiled-in image), and while it's
      totally untested the (admittedly few) code generation points I looked at
      seemed sane. And "lock orb" should be noticeably faster than "lock bts".
      
      If somebody wants to play with it, go wild. I didn't do "change_bit()",
      because nobody sane uses that thing anyway. I guarantee nothing. And if it
      breaks, nobody saw me do anything.  You can't prove this email wasn't sent
      by somebody who is good at forging smtp.
      
      This does require a gcc that is recent enough for "__builtin_constant_p()"
      to work in an inline function, but I suspect our kernel requirements are
      already higher than that. And if you do have an old gcc that is supported,
      the worst that would happen is that the optimization doesn't trigger.
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      1a750e0c
  3. 25 5月, 2008 1 次提交
  4. 22 5月, 2008 34 次提交
  5. 21 5月, 2008 3 次提交
    • D
      sunhv: Fix locking in non-paged I/O case. · 3651751f
      David S. Miller 提交于
      This causes the lock to be taken twice, thus resulting in
      a deadlock.
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3651751f
    • L
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6 · 5cf11daf
      Linus Torvalds 提交于
      * git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (21 commits)
        [CIFS] Remove debug statement
        Fix possible access to undefined memory region.
        [CIFS] Enable DFS support for Windows query path info
        [CIFS] Enable DFS support for Unix query path info
        [CIFS] add missing seq_printf to cifs_show_options for hard mount option
        [CIFS] add more complete mount options to cifs_show_options
        [CIFS] Add missing defines for DFS
        CIFSGetDFSRefer cleanup + dfs_referral_level_3 fixed to conform REFERRAL_V3 the MS-DFSC spec.
        Fixed DFS code to work with new 'build_path_from_dentry', that returns full path if share in the dfs, now.
        [CIFS] enable parsing for transport encryption mount parm
        [CIFS] Finishup DFS code
        [CIFS] BKL-removal: convert CIFS over to unlocked_ioctl
        [CIFS] suppress duplicate warning
        [CIFS] Fix paths when share is in DFS to include proper prefix
        add function to convert access flags to legacy open mode
        clarify return value of cifs_convert_flags()
        [CIFS] don't explicitly do a FindClose on rewind when directory search has ended
        [CIFS] cleanup old checkpatch warnings
        [CIFS] CIFSSMBPosixLock should return -EINVAL on error
        fix memory leak in CIFSFindNext
        ...
      5cf11daf
    • S
      [CIFS] Remove debug statement · 397d71dd
      Steve French 提交于
      Signed-off-by: NSteve French <sfrench@us.ibm.com>
      397d71dd
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