From: Dietmar Eggemann dietmar.eggemann@arm.com
[ Upstream commit f4904815f97a934258445a8f763f6b6c48f007e7 ]
{push,pull}_dl_task() always calls {de,}activate_task() with .flags=0 which sets p->on_rq=TASK_ON_RQ_MIGRATING.
{push,pull}_dl_task()->{de,}activate_task()->{de,en}queue_task()-> {de,en}queue_task_dl() calls {sub,add}_{running,rq}_bw() since p->on_rq==TASK_ON_RQ_MIGRATING. So {sub,add}_{running,rq}_bw() in {push,pull}_dl_task() is double-accounting for that task.
Fix it by removing rq/running bw accounting in [push/pull]_dl_task().
Fixes: 7dd778841164 ("sched/core: Unify p->on_rq updates") Signed-off-by: Dietmar Eggemann dietmar.eggemann@arm.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Cc: Valentin Schneider valentin.schneider@arm.com Cc: Ingo Molnar mingo@kernel.org Cc: Luca Abeni luca.abeni@santannapisa.it Cc: Daniel Bristot de Oliveira bristot@redhat.com Cc: Juri Lelli juri.lelli@redhat.com Cc: Qais Yousef qais.yousef@arm.com Link: https://lkml.kernel.org/r/20190802145945.18702-2-dietmar.eggemann@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/sched/deadline.c | 8 -------- 1 file changed, 8 deletions(-)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 43901fa3f2693..1c66480afda81 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -2088,17 +2088,13 @@ static int push_dl_task(struct rq *rq) }
deactivate_task(rq, next_task, 0); - sub_running_bw(&next_task->dl, &rq->dl); - sub_rq_bw(&next_task->dl, &rq->dl); set_task_cpu(next_task, later_rq->cpu); - add_rq_bw(&next_task->dl, &later_rq->dl);
/* * Update the later_rq clock here, because the clock is used * by the cpufreq_update_util() inside __add_running_bw(). */ update_rq_clock(later_rq); - add_running_bw(&next_task->dl, &later_rq->dl); activate_task(later_rq, next_task, ENQUEUE_NOCLOCK); ret = 1;
@@ -2186,11 +2182,7 @@ static void pull_dl_task(struct rq *this_rq) resched = true;
deactivate_task(src_rq, p, 0); - sub_running_bw(&p->dl, &src_rq->dl); - sub_rq_bw(&p->dl, &src_rq->dl); set_task_cpu(p, this_cpu); - add_rq_bw(&p->dl, &this_rq->dl); - add_running_bw(&p->dl, &this_rq->dl); activate_task(this_rq, p, 0); dmin = p->dl.deadline;