diff options
| author |   Vincent Guittot <vincent.guittot@linaro.org> | 2018-04-26 12:19:32 +0200 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2018-05-03 07:38:03 +0200 |
| commit | 457be908c83637ee10bda085a23dc05afa3b14a0 (patch) | |
| tree | e578083954eca7d085ad6428ca5ddc140657c40a /kernel | |
| parent | stop_machine, sched: Fix migrate_swap() vs. active_balance() deadlock (diff) | |
| download | linux-dev-457be908c83637ee10bda085a23dc05afa3b14a0.tar.xz linux-dev-457be908c83637ee10bda085a23dc05afa3b14a0.zip | |
sched/fair: Fix the update of blocked load when newly idle
With commit:
31e77c93e432 ("sched/fair: Update blocked load when newly idle")
... we release the rq->lock when updating blocked load of idle CPUs.
This opens a time window during which another CPU can add a task to this
CPU's cfs_rq.
The check for newly added task of idle_balance() is not in the common path.
Move the out label to include this check.
Reported-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 31e77c93e432 ("sched/fair: Update blocked load when newly idle")
Link: http://lkml.kernel.org/r/20180426103133.GA6953@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/fair.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 54dc31e7ab9b..e3002e5ada31 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -9847,6 +9847,7 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf) if (curr_cost > this_rq->max_idle_balance_cost) this_rq->max_idle_balance_cost = curr_cost; +out: /* * While browsing the domains, we released the rq lock, a task could * have been enqueued in the meantime. Since we're not going idle, @@ -9855,7 +9856,6 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf) if (this_rq->cfs.h_nr_running && !pulled_task) pulled_task = 1; -out: /* Move the next balance forward */ if (time_after(this_rq->next_balance, next_balance)) this_rq->next_balance = next_balance; |