1. 23 12月, 2006 2 次提交
  2. 21 12月, 2006 1 次提交
    • P
      [PATCH] sched: improve efficiency of sched_fork() · bc947631
      Peter Williams 提交于
      Problem:
        sched_fork() has always called scheduler_tick() in some (unlikely)
        circumstances in order to update the current task in light of those
        circumstances.  It has always been the case that the work done by
        scheduler_tick() was more than was required to handle the problem in
        hand but no harm was done except for the waste of a few CPU cycles.
      
        However, the splitting of scheduler_tick() into two procedures in
        2.6.20-rc1 enables the wasted cycles to be saved as the new procedure
        task_running_tick() does all the work that is required to rectify the
        problem being handled.
      
      Solution:
        Replace the call to scheduler_tick() in sched_fork() with a call to
        task_running_tick().
      Signed-off-by: NPeter Williams <pwil3058@bigpond.com.au>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      bc947631
  3. 14 12月, 2006 1 次提交
  4. 11 12月, 2006 16 次提交
  5. 08 12月, 2006 7 次提交
  6. 21 10月, 2006 1 次提交
  7. 12 10月, 2006 1 次提交
    • N
      [PATCH] sched: likely profiling · beed33a8
      Nick Piggin 提交于
      This likely profiling is pretty fun. I found a few possible problems
      in sched.c.
      
      This patch may be not measurable, but when I did measure long ago,
      nooping (un)likely cost a couple of % on scheduler heavy benchmarks, so
      it all adds up.
      
      Tweak some branch hints:
      
      - the 2nd 64 bits in the bitmask is likely to be populated, because it
        contains the first 28 bits (nearly 3/4) of the normal priorities.
        (ratio of 669669:691 ~= 1000:1).
      
      - it isn't unlikely that context switching switches to another process. it
        might be very rapidly switching to and from the idle process (ratio of
        475815:419004 and 471330:423544). Let the branch predictor decide.
      
      - preempt_enable seems to be very often called in a nested preempt_disable
        or with interrupts disabled (ratio of 3567760:87965 ~= 40:1)
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: Daniel Walker <dwalker@mvista.com>
      Cc: Hua Zhong <hzhong@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      beed33a8
  8. 03 10月, 2006 7 次提交
  9. 02 10月, 2006 1 次提交
  10. 01 10月, 2006 1 次提交
    • J
      [PATCH] csa: convert CONFIG tag for extended accounting routines · 8f0ab514
      Jay Lan 提交于
      There were a few accounting data/macros that are used in CSA but are #ifdef'ed
      inside CONFIG_BSD_PROCESS_ACCT.  This patch is to change those ifdef's from
      CONFIG_BSD_PROCESS_ACCT to CONFIG_TASK_XACCT.  A few defines are moved from
      kernel/acct.c and include/linux/acct.h to kernel/tsacct.c and
      include/linux/tsacct_kern.h.
      Signed-off-by: NJay Lan <jlan@sgi.com>
      Cc: Shailabh Nagar <nagar@watson.ibm.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Cc: Jes Sorensen <jes@sgi.com>
      Cc: Chris Sturtivant <csturtiv@sgi.com>
      Cc: Tony Ernst <tee@sgi.com>
      Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      8f0ab514
  11. 30 9月, 2006 2 次提交