[PATCH] use smp_mb/wmb/rmb where possible
Replace a number of memory barriers with smp_ variants. This means we won't
take the unnecessary hit on UP machines.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/lib/rwsem-spinlock.c b/lib/rwsem-spinlock.c
index 21f0db2..40ffde9 100644
--- a/lib/rwsem-spinlock.c
+++ b/lib/rwsem-spinlock.c
@@ -76,7 +76,7 @@
list_del(&waiter->list);
tsk = waiter->task;
/* Don't touch waiter after ->task has been NULLed */
- mb();
+ smp_mb();
waiter->task = NULL;
wake_up_process(tsk);
put_task_struct(tsk);
@@ -91,7 +91,7 @@
list_del(&waiter->list);
tsk = waiter->task;
- mb();
+ smp_mb();
waiter->task = NULL;
wake_up_process(tsk);
put_task_struct(tsk);
@@ -123,7 +123,7 @@
list_del(&waiter->list);
tsk = waiter->task;
- mb();
+ smp_mb();
waiter->task = NULL;
wake_up_process(tsk);
put_task_struct(tsk);
diff --git a/lib/rwsem.c b/lib/rwsem.c
index 7644089..62fa4eb 100644
--- a/lib/rwsem.c
+++ b/lib/rwsem.c
@@ -74,7 +74,7 @@
*/
list_del(&waiter->list);
tsk = waiter->task;
- mb();
+ smp_mb();
waiter->task = NULL;
wake_up_process(tsk);
put_task_struct(tsk);
@@ -117,7 +117,7 @@
waiter = list_entry(next, struct rwsem_waiter, list);
next = waiter->list.next;
tsk = waiter->task;
- mb();
+ smp_mb();
waiter->task = NULL;
wake_up_process(tsk);
put_task_struct(tsk);