sched/core: Add missing update_rq_clock() in post_init_entity_util_avg()

Address this rq-clock update bug:

  WARNING: CPU: 0 PID: 0 at ../kernel/sched/sched.h:797 post_init_entity_util_avg()
  rq->clock_update_flags < RQCF_ACT_SKIP

  Call Trace:
    __warn()
    post_init_entity_util_avg()
    wake_up_new_task()
    _do_fork()
    kernel_thread()
    rest_init()
    start_kernel()

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 311460b46d688e1f9f53a3439aa81704c19c84b0..9217c3221b0d4cea7686091022285d8f14b9df33 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2578,6 +2578,7 @@ void wake_up_new_task(struct task_struct *p)
        __set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0));
 #endif
        rq = __task_rq_lock(p, &rf);
+       update_rq_clock(rq);
        post_init_entity_util_avg(&p->se);
 
        activate_task(rq, p, 0);

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index faf80e10d6625ac2d0e0a47171f69fcee5e5d8ff..972b676229220119fb2ebcdf0a2503919da4ce84 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9267,6 +9267,7 @@ void online_fair_sched_group(struct task_group *tg)
                se = tg->se[i];
 
                raw_spin_lock_irq(&rq->lock);
+               update_rq_clock(rq);
                attach_entity_cfs_rq(se);
                sync_throttle(tg, i);
                raw_spin_unlock_irq(&rq->lock);