Commit-ID: a776b968e52895a350d636e6e7fdcb3b10846fa4 Gitweb: http://git.kernel.org/tip/a776b968e52895a350d636e6e7fdcb3b10846fa4 Author: Byungchul Park <[email protected]> AuthorDate: Fri, 12 May 2017 10:05:59 +0900 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 23 May 2017 10:01:33 +0200
sched/deadline: Remove unnecessary condition in push_dl_task() pick_next_pushable_dl_task(rq) has BUG_ON(rq->cpu != task_cpu(task)) when it returns a task other than NULL, which means that task_cpu(task) must be rq->cpu. So if task == next_task, then task_cpu(next_task) must be rq->cpu as well. Remove the redundant condition and make the code simpler. This way one unnecessary branch and two LOAD operations can be avoided. Signed-off-by: Byungchul Park <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Reviewed-by: Steven Rostedt (VMware) <[email protected]> Reviewed-by: Juri Lelli <[email protected]> Reviewed-by: Daniel Bristot de Oliveira <[email protected]> Cc: <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- kernel/sched/deadline.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index a2ce590..df6c291 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1533,7 +1533,7 @@ retry: * then possible that next_task has migrated. */ task = pick_next_pushable_dl_task(rq); - if (task_cpu(next_task) == rq->cpu && task == next_task) { + if (task == next_task) { /* * The task is still there. We don't try * again, some other cpu will pull it when ready.
