Commit-ID: a7711602c7b79950ea437178f601b52ab08ef659 Gitweb: https://git.kernel.org/tip/a7711602c7b79950ea437178f601b52ab08ef659 Author: Wen Yang <[email protected]> AuthorDate: Tue, 6 Feb 2018 09:53:28 +0800 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 13 Feb 2018 11:44:41 +0100
sched/rt: Make update_curr_rt() more accurate rq->clock_task may be updated between the two calls of rq_clock_task() in update_curr_rt(). Calling rq_clock_task() only once makes it more accurate and efficient, taking update_curr() as reference. Signed-off-by: Wen Yang <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Reviewed-by: Jiang Biao <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- kernel/sched/rt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 663b235..aad49451 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -950,12 +950,13 @@ static void update_curr_rt(struct rq *rq) { struct task_struct *curr = rq->curr; struct sched_rt_entity *rt_se = &curr->rt; - u64 now = rq_clock_task(rq); u64 delta_exec; + u64 now; if (curr->sched_class != &rt_sched_class) return; + now = rq_clock_task(rq); delta_exec = now - curr->se.exec_start; if (unlikely((s64)delta_exec <= 0)) return;
