From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752094AbcAEJRa (ORCPT ); Tue, 5 Jan 2016 04:17:30 -0500 Received: from LGEAMRELO12.lge.com ([156.147.23.52]:48436 "EHLO lgeamrelo12.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751857AbcAEJQo (ORCPT ); Tue, 5 Jan 2016 04:16:44 -0500 X-Original-SENDERIP: 156.147.1.151 X-Original-MAILFROM: byungchul.park@lge.com X-Original-SENDERIP: 10.177.222.33 X-Original-MAILFROM: byungchul.park@lge.com From: Byungchul Park To: stable@vger.kernel.org Cc: peterz@infradead.org, linux-kernel@vger.kernel.org, ktkhai@parallels.com, rostedt@goodmis.org, juri.lelli@gmail.com, pang.xunlei@linaro.org, oleg@redhat.com, wanpeng.li@linux.intel.com, umgwanakikbuti@gmail.com, Thomas Gleixner Subject: [PATCH for v3.14.58 7/7] sched, dl: Convert switched_{from, to}_dl() / prio_changed_dl() to balance callbacks Date: Tue, 5 Jan 2016 18:16:28 +0900 Message-Id: <1451985388-19492-7-git-send-email-byungchul.park@lge.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1451985388-19492-1-git-send-email-byungchul.park@lge.com> References: <20160105085211.GB3621@X58A-UD3R> <1451985388-19492-1-git-send-email-byungchul.park@lge.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra Remove the direct {push,pull} balancing operations from switched_{from,to}_dl() / prio_changed_dl() and use the balance callback queue. Again, err on the side of too many reschedules; since too few is a hard bug while too many is just annoying. Signed-off-by: Peter Zijlstra (Intel) Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.968262663@infradead.org Signed-off-by: Thomas Gleixner Signed-off-by: Byungchul Park Conflicts: kernel/sched/deadline.c --- kernel/sched/deadline.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index ec1f21d..6ab59bb 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -210,16 +210,23 @@ static inline int has_pushable_dl_tasks(struct rq *rq) static int push_dl_task(struct rq *rq); -static DEFINE_PER_CPU(struct callback_head, dl_balance_head); +static DEFINE_PER_CPU(struct callback_head, dl_push_head); +static DEFINE_PER_CPU(struct callback_head, dl_pull_head); static void push_dl_tasks(struct rq *); +static void pull_dl_task(struct rq *); static inline void queue_push_tasks(struct rq *rq) { if (!has_pushable_dl_tasks(rq)) return; - queue_balance_callback(rq, &per_cpu(dl_balance_head, rq->cpu), push_dl_tasks); + queue_balance_callback(rq, &per_cpu(dl_push_head, rq->cpu), push_dl_tasks); +} + +static inline void queue_pull_task(struct rq *rq) +{ + queue_balance_callback(rq, &per_cpu(dl_pull_head, rq->cpu), pull_dl_task); } #else @@ -247,6 +254,10 @@ void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) static inline void queue_push_tasks(struct rq *rq) { } + +static inline void queue_pull_task(struct rq *rq) +{ +} #endif /* CONFIG_SMP */ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags); @@ -1541,7 +1552,7 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p) * from an overloaded cpu, if any. */ if (!rq->dl.dl_nr_running) - pull_dl_task(rq); + queue_pull_task(rq); #endif } @@ -1551,8 +1562,6 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p) */ static void switched_to_dl(struct rq *rq, struct task_struct *p) { - int check_resched = 1; - /* * If p is throttled, don't consider the possibility * of preempting rq->curr, the check will be done right @@ -1563,12 +1572,12 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) if (p->on_rq || rq->curr != p) { #ifdef CONFIG_SMP - if (rq->dl.overloaded && push_dl_task(rq) && rq != task_rq(p)) - /* Only reschedule if pushing failed */ - check_resched = 0; -#endif /* CONFIG_SMP */ - if (check_resched && task_has_dl_policy(rq->curr)) + if (rq->dl.overloaded) + queue_push_tasks(rq); +#else + if (task_has_dl_policy(rq->curr)) check_preempt_curr_dl(rq, p, 0); +#endif /* CONFIG_SMP */ } } @@ -1588,15 +1597,14 @@ static void prio_changed_dl(struct rq *rq, struct task_struct *p, * or lowering its prio, so... */ if (!rq->dl.overloaded) - pull_dl_task(rq); + queue_pull_task(rq); /* * If we now have a earlier deadline task than p, * then reschedule, provided p is still on this * runqueue. */ - if (dl_time_before(rq->dl.earliest_dl.curr, p->dl.deadline) && - rq->curr == p) + if (dl_time_before(rq->dl.earliest_dl.curr, p->dl.deadline)) resched_task(p); #else /* -- 1.9.1