[PATCH] lockdep: annotate waitqueues
Create one lock class for all waitqueue locks in the kernel. Has no effect on
non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/wait.h b/include/linux/wait.h
index bc4f389..794be7a 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -77,9 +77,15 @@
#define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
{ .flags = word, .bit_nr = bit, }
+/*
+ * lockdep: we want one lock-class for all waitqueue locks.
+ */
+extern struct lock_class_key waitqueue_lock_key;
+
static inline void init_waitqueue_head(wait_queue_head_t *q)
{
spin_lock_init(&q->lock);
+ lockdep_set_class(&q->lock, &waitqueue_lock_key);
INIT_LIST_HEAD(&q->task_list);
}
diff --git a/kernel/wait.c b/kernel/wait.c
index 5985d86..a1d57ae 100644
--- a/kernel/wait.c
+++ b/kernel/wait.c
@@ -10,6 +10,10 @@
#include <linux/wait.h>
#include <linux/hash.h>
+struct lock_class_key waitqueue_lock_key;
+
+EXPORT_SYMBOL(waitqueue_lock_key);
+
void fastcall add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait)
{
unsigned long flags;
