SLUB: fix locking for hotplug callbacks

Hotplug callbacks are performed with interrupts enabled. Slub requires interrupts to be disabled for flushing caches. Signed-off-by: Christoph Lameter <[email protected]> Cc: Michal Piotrowski <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
mna · Jun 1, 2007 · 27390bc · 27390bc
1 parent ac140a8
commit 27390bc
Showing 1 changed file with 14 additions and 1 deletion.
diff --git a/mm/slub.c b/mm/slub.c
@@ -2607,6 +2607,19 @@ static void for_all_slabs(void (*func)(struct kmem_cache *, int), int cpu)
 	up_read(&slub_lock);
 }
 
+/*
+ * Version of __flush_cpu_slab for the case that interrupts
+ * are enabled.
+ */
+static void cpu_slab_flush(struct kmem_cache *s, int cpu)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	__flush_cpu_slab(s, cpu);
+	local_irq_restore(flags);
+}
+
 /*
  * Use the cpu notifier to insure that the cpu slabs are flushed when
  * necessary.
@@ -2621,7 +2634,7 @@ static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
 	case CPU_UP_CANCELED_FROZEN:
 	case CPU_DEAD:
 	case CPU_DEAD_FROZEN:
-		for_all_slabs(__flush_cpu_slab, cpu);
+		for_all_slabs(cpu_slab_flush, cpu);
 		break;
 	default:
 		break;