From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751440AbaDSKz6 (ORCPT ); Sat, 19 Apr 2014 06:55:58 -0400 Received: from mail-ee0-f52.google.com ([74.125.83.52]:62697 "EHLO mail-ee0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751043AbaDSKz4 (ORCPT ); Sat, 19 Apr 2014 06:55:56 -0400 Date: Sat, 19 Apr 2014 12:55:49 +0200 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Mike Galbraith , Thomas Gleixner , Andrew Morton Subject: [GIT PULL] scheduler fixes Message-ID: <20140419105549.GA4492@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the latest sched-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-urgent-for-linus # HEAD: a1d9a3231eac4117cadaf4b6bba5b2902c15a33e sched: Check for stop task appearance when balancing happens Two fixes: - a SCHED_DEADLINE task selection fix - a sched/numa related lockdep splat fix Thanks, Ingo ------------------> Kirill Tkhai (1): sched: Check for stop task appearance when balancing happens Mike Galbraith (1): sched/numa: Fix task_numa_free() lockdep splat kernel/sched/deadline.c | 11 ++++++++++- kernel/sched/fair.c | 16 +++++++++------- kernel/sched/rt.c | 7 ++++--- kernel/sched/sched.h | 9 +++++++++ 4 files changed, 32 insertions(+), 11 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 27ef409..b080957 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 7e9bd0b..7570dd9 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1497,7 +1497,7 @@ static void task_numa_placement(struct task_struct *p) /* If the task is part of a group prevent parallel updates to group stats */ if (p->numa_group) { group_lock = &p->numa_group->lock; - spin_lock(group_lock); + spin_lock_irq(group_lock); } /* Find the node with the highest number of faults */ @@ -1572,7 +1572,7 @@ static void task_numa_placement(struct task_struct *p) } } - spin_unlock(group_lock); + spin_unlock_irq(group_lock); } /* Preferred node as the node with the most faults */ @@ -1677,7 +1677,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags, if (!join) return; - double_lock(&my_grp->lock, &grp->lock); + BUG_ON(irqs_disabled()); + double_lock_irq(&my_grp->lock, &grp->lock); for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++) { my_grp->faults[i] -= p->numa_faults_memory[i]; @@ -1691,7 +1692,7 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags, grp->nr_tasks++; spin_unlock(&my_grp->lock); - spin_unlock(&grp->lock); + spin_unlock_irq(&grp->lock); rcu_assign_pointer(p->numa_group, grp); @@ -1710,14 +1711,14 @@ void task_numa_free(struct task_struct *p) void *numa_faults = p->numa_faults_memory; if (grp) { - spin_lock(&grp->lock); + spin_lock_irq(&grp->lock); for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++) grp->faults[i] -= p->numa_faults_memory[i]; grp->total_faults -= p->total_numa_faults; list_del(&p->numa_entry); grp->nr_tasks--; - spin_unlock(&grp->lock); + spin_unlock_irq(&grp->lock); rcu_assign_pointer(p->numa_group, NULL); put_numa_group(grp); } @@ -6727,7 +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 d8cdf16..bd2267a 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; } diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index c9007f2..456e492 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1385,6 +1385,15 @@ static inline void double_lock(spinlock_t *l1, spinlock_t *l2) spin_lock_nested(l2, SINGLE_DEPTH_NESTING); } +static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) +{ + if (l1 > l2) + swap(l1, l2); + + spin_lock_irq(l1); + spin_lock_nested(l2, SINGLE_DEPTH_NESTING); +} + static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) { if (l1 > l2)