sched: Update rq clock before setting fair group shares

Because we may update the execution time in

    sched_group_set_shares()->update_cfs_shares()->reweight_entity()->update_curr()

before reweighting the entity while setting the group shares and this requires
an uptodate version of the runqueue clock.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365724262-20142-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index f62b16dfba636825b60f6ef1b0991da3141b4d4b..f76ca21711bb7740a0667016fd3ba1a49c286a58 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6107,6 +6107,9 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
                se = tg->se[i];
                /* Propagate contribution to hierarchy */
                raw_spin_lock_irqsave(&rq->lock, flags);
+
+               /* Possible calls to update_curr() need rq clock */
+               update_rq_clock(rq);
                for_each_sched_entity(se)
                        update_cfs_shares(group_cfs_rq(se));
                raw_spin_unlock_irqrestore(&rq->lock, flags);