[PATCH 1/2] task_work: minor cleanups

[Oleg Nesterov <oleg@redhat.com>]

Trivial. Remove the unnecessary "work = NULL" initialization
and turn read_barrier_depends() into smp_read_barrier_depends()
in task_work_cancel().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
 kernel/task_work.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/task_work.c b/kernel/task_work.c
index 65bd3c9..6ee0985 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -25,7 +25,7 @@ struct callback_head *
 task_work_cancel(struct task_struct *task, task_work_func_t func)
 {
 	struct callback_head **pprev = &task->task_works;
-	struct callback_head *work = NULL;
+	struct callback_head *work;
 	unsigned long flags;
 	/*
 	 * If cmpxchg() fails we continue without updating pprev.
@@ -35,7 +35,7 @@ task_work_cancel(struct task_struct *task, task_work_func_t func)
 	 */
 	raw_spin_lock_irqsave(&task->pi_lock, flags);
 	while ((work = ACCESS_ONCE(*pprev))) {
-		read_barrier_depends();
+		smp_read_barrier_depends();
 		if (work->func != func)
 			pprev = &work->next;
 		else if (cmpxchg(pprev, work, work->next) == work)
-- 
1.5.5.1