1. 05 2月, 2009 2 次提交
    • P
      timers: split process wide cpu clocks/timers · 4cd4c1b4
      Peter Zijlstra 提交于
      Change the process wide cpu timers/clocks so that we:
      
       1) don't mess up the kernel with too many threads,
       2) don't have a per-cpu allocation for each process,
       3) have no impact when not used.
      
      In order to accomplish this we're going to split it into two parts:
      
       - clocks; which can take all the time they want since they run
                 from user context -- ie. sys_clock_gettime(CLOCK_PROCESS_CPUTIME_ID)
      
       - timers; which need constant time sampling but since they're
                 explicity used, the user can pay the overhead.
      
      The clock readout will go back to a full sum of the thread group, while the
      timers will run of a global 'clock' that only runs when needed, so only
      programs that make use of the facility pay the price.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Reviewed-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      4cd4c1b4
    • P
      signal: re-add dead task accumulation stats. · 32bd671d
      Peter Zijlstra 提交于
      We're going to split the process wide cpu accounting into two parts:
      
       - clocks; which can take all the time they want since they run
                 from user context.
      
       - timers; which need constant time tracing but can affort the overhead
                 because they're default off -- and rare.
      
      The clock readout will go back to a full sum of the thread group, for this
      we need to re-add the exit stats that were removed in the initial itimer
      rework (f06febc9: timers: fix itimer/many thread hang).
      
      Furthermore, since that full sum can be rather slow for large thread groups
      and we have the complete dead task stats, revert the do_notify_parent time
      computation.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Reviewed-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      32bd671d
  2. 03 2月, 2009 2 次提交
  3. 02 2月, 2009 3 次提交
  4. 31 1月, 2009 33 次提交