diff options
| author |   Ulrich Obergfell <uobergfe@redhat.com> | 2015-11-05 18:44:53 -0800 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2015-11-05 19:34:48 -0800 |
| commit | a2a45b85ec45db4b041ea5d93b21033dbc3cc0fc (patch) | |
| tree | dc9ae8545451962f41fd518194b29977080e3842 /kernel/watchdog.c | |
| parent | kernel/watchdog.c: avoid races between /proc handlers and CPU hotplug (diff) | |
| download | linux-dev-a2a45b85ec45db4b041ea5d93b21033dbc3cc0fc.tar.xz linux-dev-a2a45b85ec45db4b041ea5d93b21033dbc3cc0fc.zip | |
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>
Diffstat (limited to 'kernel/watchdog.c')
| -rw-r--r-- | kernel/watchdog.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 13fdda1a4c91..84c4744d1977 100644 --- 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(); } /* |