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Subject[PATCH 3/4] watchdog: remove {get|put}_online_cpus() from watchdog_{park|unpark}_threads()
Date
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>
---
kernel/watchdog.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 13fdda1..84c4744 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();
}

/*
--
1.7.11.7


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