Commit-ID: abfafa54db9aba404e8e6763503f04d35bd07138 Gitweb: http://git.kernel.org/tip/abfafa54db9aba404e8e6763503f04d35bd07138 Author: Jason Low <jason.low2@xxxxxx> AuthorDate: Fri, 13 Sep 2013 11:26:51 -0700 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Fri, 20 Sep 2013 12:03:41 +0200 sched: Reduce overestimating rq->avg_idle When updating avg_idle, if the delta exceeds some max value, then avg_idle gets set to the max, regardless of what the previous avg was. This can cause avg_idle to often be overestimated. This patch modifies the way we update avg_idle by always updating it with the function call to update_avg() first. Then, if avg_idle exceeds the max, we set it to the max. Signed-off-by: Jason Low <jason.low2@xxxxxx> Reviewed-by: Rik van Riel <riel@xxxxxxxxxx> Reviewed-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1379096813-3032-2-git-send-email-jason.low2@xxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- kernel/sched/core.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5ac63c9..048f39e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1332,10 +1332,11 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) u64 delta = rq_clock(rq) - rq->idle_stamp; u64 max = 2*sysctl_sched_migration_cost; - if (delta > max) + update_avg(&rq->avg_idle, delta); + + if (rq->avg_idle > max) rq->avg_idle = max; - else - update_avg(&rq->avg_idle, delta); + rq->idle_stamp = 0; } #endif -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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