slab: shut down cache_reaper when cpu goes down
Shutdown the cache_reaper if the cpu is brought down and set the
cache_reap.func to NULL. Otherwise hotplug shuts down the reaper for good.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slab.c b/mm/slab.c
index cceb347..1a7a10d 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1279,6 +1279,20 @@
start_cpu_timer(cpu);
break;
#ifdef CONFIG_HOTPLUG_CPU
+ case CPU_DOWN_PREPARE:
+ /*
+ * Shutdown cache reaper. Note that the cache_chain_mutex is
+ * held so that if cache_reap() is invoked it cannot do
+ * anything expensive but will only modify reap_work
+ * and reschedule the timer.
+ */
+ cancel_rearming_delayed_work(&per_cpu(reap_work, cpu));
+ /* Now the cache_reaper is guaranteed to be not running. */
+ per_cpu(reap_work, cpu).work.func = NULL;
+ break;
+ case CPU_DOWN_FAILED:
+ start_cpu_timer(cpu);
+ break;
case CPU_DEAD:
/*
* Even if all the cpus of a node are down, we don't free the
