1. 04 Mar, 2011 1 commit
    • Balbir Singh's avatar
      sched: Fix sched rt group scheduling when hierachy is enabled · 0c3b9168
      Balbir Singh authored
      The current sched rt code is broken when it comes to hierarchical
      scheduling, this patch fixes two problems
      
      1. It adds redundant enqueuing (harmless) when it finds a queue
         has tasks enqueued, but it has no run time and it is not
         throttled.
      
      2. The most important change is in sched_rt_rq_enqueue/dequeue.
         The code just picks the rt_rq belonging to the current cpu
         on which the period timer runs, the patch fixes it, so that
         the correct rt_se is enqueued/dequeued.
      
      Tested with a simple hierarchy
      
      /c/d, c and d assigned similar runtimes of 50,000 and a while
      1 loop runs within "d". Both c and d get throttled, without
      the patch, the task just stops running and never runs (depends
      on where the sched_rt b/w timer runs). With the patch, the
      task is throttled and runs as expected.
      
      [ bharata, suggestions on how to pick the rt_se belong to the
        rt_rq and correct cpu ]
      Signed-off-by: default avatarBalbir Singh <balbir@linux.vnet.ibm.com>
      Acked-by: default avatarBharata B Rao <bharata@linux.vnet.ibm.com>
      Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: stable@kernel.org
      LKML-Reference: <20110303113435.GA2868@balbir.in.ibm.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      0c3b9168
  2. 03 Mar, 2011 29 commits
  3. 02 Mar, 2011 10 commits