Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
authorLinus Torvalds <torvalds@linux-foundation.org>
Mon, 10 Oct 2016 17:29:59 +0000 (10:29 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 10 Oct 2016 17:29:59 +0000 (10:29 -0700)
Pull scheduler fix from Thomas Gleixner:
 "A revert of a commit which pointelessly widened a preempt disabled
  section which in turn caused might_sleep() to trigger.

  The patch intended to prevent usage of smp_processor_id() in
  preemptible context, but the usage in that case is fine because the
  thread is pinned on a single cpu and therefore cannot be migrated off"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "sched/core: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn()"

kernel/smpboot.c

index fc0d827..13bc43d 100644 (file)
@@ -122,12 +122,12 @@ static int smpboot_thread_fn(void *data)
 
                if (kthread_should_park()) {
                        __set_current_state(TASK_RUNNING);
+                       preempt_enable();
                        if (ht->park && td->status == HP_THREAD_ACTIVE) {
                                BUG_ON(td->cpu != smp_processor_id());
                                ht->park(td->cpu);
                                td->status = HP_THREAD_PARKED;
                        }
-                       preempt_enable();
                        kthread_parkme();
                        /* We might have been woken for stop */
                        continue;