task_work: minor cleanups

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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Oleg Nesterov 2013-09-11 14:23:30 -07:00 committed by Linus Torvalds
parent 202da40057
commit 205e550a0f
1 changed files with 2 additions and 2 deletions

View File

@ -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)