sched/fair: Fix the wrong throttled clock time for cfs_rq_clock_task()

Two minor fixes for cfs_rq_clock_task():

 1) If cfs_rq is currently being throttled, we need to subtract the cfs
    throttled clock time.

 2) Make "throttled_clock_task_time" update SMP unrelated. Now UP cases
    need it as well.

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1462885398-14724-1-git-send-email-xlpang@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 218f8e83db731e4afe4d4aaf7d7919a588087a12..1e87bb633d430ce02d4d89409555637030bd08ec 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3688,7 +3688,7 @@ static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
 static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq)
 {
        if (unlikely(cfs_rq->throttle_count))
-               return cfs_rq->throttled_clock_task;
+               return cfs_rq->throttled_clock_task - cfs_rq->throttled_clock_task_time;
 
        return rq_clock_task(rq_of(cfs_rq)) - cfs_rq->throttled_clock_task_time;
 }
@@ -3826,13 +3826,11 @@ static int tg_unthrottle_up(struct task_group *tg, void *data)
        struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
 
        cfs_rq->throttle_count--;
-#ifdef CONFIG_SMP
        if (!cfs_rq->throttle_count) {
                /* adjust cfs_rq_clock_task() */
                cfs_rq->throttled_clock_task_time += rq_clock_task(rq) -
                                             cfs_rq->throttled_clock_task;
        }
-#endif
 
        return 0;
 }