From a1d9a3231eac4117cadaf4b6bba5b2902c15a33e Mon Sep 17 00:00:00 2001 From: Kirill Tkhai Date: Thu, 10 Apr 2014 17:38:36 +0400 Subject: sched: Check for stop task appearance when balancing happens We need to do it like we do for the other higher priority classes.. Signed-off-by: Kirill Tkhai Cc: Michael wang Cc: Sasha Levin Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/336561397137116@web27h.yandex.ru Signed-off-by: Ingo Molnar --- kernel/sched/deadline.c | 11 ++++++++++- kernel/sched/fair.c | 3 ++- kernel/sched/rt.c | 7 ++++--- 3 files changed, 16 insertions(+), 5 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 27ef40925525..b08095786cb8 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1021,8 +1021,17 @@ struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev) dl_rq = &rq->dl; - if (need_pull_dl_task(rq, prev)) + if (need_pull_dl_task(rq, prev)) { pull_dl_task(rq); + /* + * pull_rt_task() can drop (and re-acquire) rq->lock; this + * means a stop task can slip in, in which case we need to + * re-start task selection. + */ + if (rq->stop && rq->stop->on_rq) + return RETRY_TASK; + } + /* * When prev is DL, we may throttle it in put_prev_task(). * So, we update time before we check for dl_nr_running. diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 4f14a656a720..7570dd969c28 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6728,7 +6728,8 @@ static int idle_balance(struct rq *this_rq) out: /* Is there a task of a high priority class? */ if (this_rq->nr_running != this_rq->cfs.h_nr_running && - (this_rq->dl.dl_nr_running || + ((this_rq->stop && this_rq->stop->on_rq) || + this_rq->dl.dl_nr_running || (this_rq->rt.rt_nr_running && !rt_rq_throttled(&this_rq->rt)))) pulled_task = -1; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index d8cdf1618551..bd2267ad404f 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1362,10 +1362,11 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev) pull_rt_task(rq); /* * pull_rt_task() can drop (and re-acquire) rq->lock; this - * means a dl task can slip in, in which case we need to - * re-start task selection. + * means a dl or stop task can slip in, in which case we need + * to re-start task selection. */ - if (unlikely(rq->dl.dl_nr_running)) + if (unlikely((rq->stop && rq->stop->on_rq) || + rq->dl.dl_nr_running)) return RETRY_TASK; } -- cgit v1.2.3