Merge tag 'sched_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel...

Pull scheduler fixes from Borislav Petkov:

 - Make sure the idle timer expires in hardirq context, on PREEMPT_RT

 - Make sure the run-queue balance callback is invoked only on the
   outgoing CPU

* tag 'sched_urgent_for_v5.15_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Prevent balance_push() on remote runqueues
  sched/idle: Make the idle timer expire in hard interrupt context

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c4462c4..1bba412 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8836,7 +8836,6 @@ static void balance_push(struct rq *rq)
        struct task_struct *push_task = rq->curr;
 
        lockdep_assert_rq_held(rq);
-       SCHED_WARN_ON(rq->cpu != smp_processor_id());
 
        /*
         * Ensure the thing is persistent until balance_push_set(.on = false);
@@ -8844,9 +8843,10 @@ static void balance_push(struct rq *rq)
        rq->balance_callback = &balance_push_callback;
 
        /*
-        * Only active while going offline.
+        * Only active while going offline and when invoked on the outgoing
+        * CPU.
         */
-       if (!cpu_dying(rq->cpu))
+       if (!cpu_dying(rq->cpu) || rq != this_rq())
                return;
 
        /*

diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 912b47a..d17b0a5 100644 (file)
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -379,10 +379,10 @@ void play_idle_precise(u64 duration_ns, u64 latency_ns)
        cpuidle_use_deepest_state(latency_ns);
 
        it.done = 0;
-       hrtimer_init_on_stack(&it.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       hrtimer_init_on_stack(&it.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
        it.timer.function = idle_inject_timer_fn;
        hrtimer_start(&it.timer, ns_to_ktime(duration_ns),
-                     HRTIMER_MODE_REL_PINNED);
+                     HRTIMER_MODE_REL_PINNED_HARD);
 
        while (!READ_ONCE(it.done))
                do_idle();