On Wed, 2013-01-30 at 16:50 +0400, Kirill Tkhai wrote: > There are several places of consecutive calls of dequeue_task_rt() > and put_prev_task_rt() in the scheduler. For example, function > rt_mutex_setprio() does it. > > The both calls lead to update_curr_rt(), the second of it receives > zeroed delta_exec. The only effective action in this case is call of > sched_rt_avg_update(), which can change rq->age_stamp and rq->rt_avg. > But it is possible in case of ""floating"" rq->clock. This fact is > not reasonable to be accounted. Another actions do nothing. > > Signed-off-by: Kirill V Tkhai <tkhai@xxxxxxxxx> Acked-by: Steven Rostedt <rostedt@xxxxxxxxxxx> -- Steve > CC: Ingo Molnar <mingo@xxxxxxxxxx> > CC: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > CC: linux-rt-users <linux-rt-users@xxxxxxxxxxxxxxx> > --- > kernel/sched/rt.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c > index 4e8f0f4..c6d7993 100644 > --- a/kernel/sched/rt.c > +++ b/kernel/sched/rt.c > @@ -925,8 +925,8 @@ static void update_curr_rt(struct rq *rq) > return; > > delta_exec = rq->clock_task - curr->se.exec_start; > - if (unlikely((s64)delta_exec < 0)) > - delta_exec = 0; > + if (unlikely((s64)delta_exec <= 0)) > + return; > > schedstat_set(curr->se.statistics.exec_max, > max(curr->se.statistics.exec_max, delta_exec)); -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
