Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932864AbaBUNCN (ORCPT ); Fri, 21 Feb 2014 08:02:13 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:47675 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933072AbaBUNCD (ORCPT ); Fri, 21 Feb 2014 08:02:03 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Peter Boonstoppel , Peter Zijlstra , Paul Turner , Ingo Molnar , Li Zefan , Luis Henriques Subject: [PATCH 3.5 17/60] sched: Unthrottle rt runqueues in __disable_runtime() Date: Fri, 21 Feb 2014 13:00:44 +0000 Message-Id: <1392987687-15367-18-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1392987687-15367-1-git-send-email-luis.henriques@canonical.com> References: <1392987687-15367-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.31 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Boonstoppel commit a4c96ae319b8047f62dedbe1eac79e321c185749 upstream. migrate_tasks() uses _pick_next_task_rt() to get tasks from the real-time runqueues to be migrated. When rt_rq is throttled _pick_next_task_rt() won't return anything, in which case migrate_tasks() can't move all threads over and gets stuck in an infinite loop. Instead unthrottle rt runqueues before migrating tasks. Additionally: move unthrottle_offline_cfs_rqs() to rq_offline_fair() Signed-off-by: Peter Boonstoppel Signed-off-by: Peter Zijlstra Cc: Paul Turner Link: http://lkml.kernel.org/r/5FBF8E85CA34454794F0F7ECBA79798F379D3648B7@HQMAIL04.nvidia.com Signed-off-by: Ingo Molnar Cc: Li Zefan Signed-off-by: Luis Henriques --- kernel/sched/core.c | 3 --- kernel/sched/fair.c | 7 +++++-- kernel/sched/rt.c | 1 + kernel/sched/sched.h | 1 - 4 files changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 281f186..57d8625 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5357,9 +5357,6 @@ static void migrate_tasks(unsigned int dead_cpu) */ rq->stop = NULL; - /* Ensure any throttled groups are reachable by pick_next_task */ - unthrottle_offline_cfs_rqs(rq); - for ( ; ; ) { /* * There's this thread running, bail when that's the only diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9e2fe1b..7963693 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2071,7 +2071,7 @@ static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) hrtimer_cancel(&cfs_b->slack_timer); } -void unthrottle_offline_cfs_rqs(struct rq *rq) +static void unthrottle_offline_cfs_rqs(struct rq *rq) { struct cfs_rq *cfs_rq; @@ -2125,7 +2125,7 @@ static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) return NULL; } static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {} -void unthrottle_offline_cfs_rqs(struct rq *rq) {} +static inline void unthrottle_offline_cfs_rqs(struct rq *rq) {} #endif /* CONFIG_CFS_BANDWIDTH */ @@ -4910,6 +4910,9 @@ static void rq_online_fair(struct rq *rq) static void rq_offline_fair(struct rq *rq) { update_sysctl(); + + /* Ensure any throttled groups are reachable by pick_next_task */ + unthrottle_offline_cfs_rqs(rq); } #endif /* CONFIG_SMP */ diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 06c3c6f..ad4787b 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -691,6 +691,7 @@ balanced: * runtime - in which case borrowing doesn't make sense. */ rt_rq->rt_runtime = RUNTIME_INF; + rt_rq->rt_throttled = 0; raw_spin_unlock(&rt_rq->rt_runtime_lock); raw_spin_unlock(&rt_b->rt_runtime_lock); } diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 65bd8a8..400391f 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1140,7 +1140,6 @@ extern void print_rt_stats(struct seq_file *m, int cpu); extern void init_cfs_rq(struct cfs_rq *cfs_rq); extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq); -extern void unthrottle_offline_cfs_rqs(struct rq *rq); extern void cfs_bandwidth_usage_inc(void); extern void cfs_bandwidth_usage_dec(void); -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/