macvtap: use prepare_to_wait/finish_wait to ensure mb

instead of raw assignment to current->state

Signed-off-by: Hong Zhiguo <honkiko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Hong zhi guo 2012-06-06 22:36:27 +00:00 committed by David S. Miller
parent e9939c80e9
commit ccf7e72b54

View File

@ -847,13 +847,12 @@ static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb,
const struct iovec *iv, unsigned long len,
int noblock)
{
DECLARE_WAITQUEUE(wait, current);
DEFINE_WAIT(wait);
struct sk_buff *skb;
ssize_t ret = 0;
add_wait_queue(sk_sleep(&q->sk), &wait);
while (len) {
current->state = TASK_INTERRUPTIBLE;
prepare_to_wait(sk_sleep(&q->sk), &wait, TASK_INTERRUPTIBLE);
/* Read frames from the queue */
skb = skb_dequeue(&q->sk.sk_receive_queue);
@ -875,8 +874,7 @@ static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb,
break;
}
current->state = TASK_RUNNING;
remove_wait_queue(sk_sleep(&q->sk), &wait);
finish_wait(sk_sleep(&q->sk), &wait);
return ret;
}