kernel/watchdog.c: remove {get|put}_online_cpus() from watchdog_{park|unpark}_threads()

watchdog_{park|unpark}_threads() are now called in code paths that protect
themselves against CPU hotplug, so {get|put}_online_cpus() calls are
redundant and can be removed.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 13fdda1a4c91b52e14076026304b4188b49a4ad7..84c4744d19775c476addcfb87b9ee50b34f08951 100644 (file)
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -683,33 +683,35 @@ static struct smp_hotplug_thread watchdog_threads = {
  * be parked and the watchdog threads of other CPUs can still be runnable.
  * Callers are expected to handle this special condition as appropriate in
  * their context.
+ *
+ * This function may only be called in a context that is protected against
+ * races with CPU hotplug - for example, via get_online_cpus().
  */
 static int watchdog_park_threads(void)
 {
        int cpu, ret = 0;
 
-       get_online_cpus();
        for_each_watchdog_cpu(cpu) {
                ret = kthread_park(per_cpu(softlockup_watchdog, cpu));
                if (ret)
                        break;
        }
-       put_online_cpus();
 
        return ret;
 }
 
 /*
  * unpark all watchdog threads that are specified in 'watchdog_cpumask'
+ *
+ * This function may only be called in a context that is protected against
+ * races with CPU hotplug - for example, via get_online_cpus().
  */
 static void watchdog_unpark_threads(void)
 {
        int cpu;
 
-       get_online_cpus();
        for_each_watchdog_cpu(cpu)
                kthread_unpark(per_cpu(softlockup_watchdog, cpu));
-       put_online_cpus();
 }
 
 /*