[PATCH] lockdep: annotate waitqueues
Ingo Molnar [Mon, 3 Jul 2006 07:25:07 +0000 (00:25 -0700)]
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>

include/linux/wait.h
kernel/wait.c

index bc4f389..794be7a 100644 (file)
@@ -77,9 +77,15 @@ struct task_struct;
 #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);
 }
 
index 5985d86..a1d57ae 100644 (file)
 #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;