diff mbox

macvtap: use set_curren_state to ensure mb

Message ID CAA7+ByUH8LsSrbetHngEZmaHkvK5aUO5v7-F=+wbveo6q68f-g@mail.gmail.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Hong zhi guo June 5, 2012, 12:05 p.m. UTC 
On Tue, Jun 5, 2012 at 7:05 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Why not using the more standard :
>
> prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
>
> and
>
> finish_wait(sk_sleep(sk), &wait);
>

Thanks for your comments.  The difference is that prepare_to_wait
inside loop introduces extra "list_empty" judgement than original
patch. But personally I prefer the newer version too:

Signed-off-by: Hong Zhiguo <honkiko@gmail.com>
---
 drivers/net/macvtap.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

 		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;
 }

Comments

David Miller June 6, 2012, 5:48 p.m. UTC | #1 
From: Hong zhi guo <honkiko@gmail.com>
Date: Tue, 5 Jun 2012 20:05:34 +0800

> On Tue, Jun 5, 2012 at 7:05 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>> Why not using the more standard :
>>
>> prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
>>
>> and
>>
>> finish_wait(sk_sleep(sk), &wait);
>>
> 
> Thanks for your comments.  The difference is that prepare_to_wait
> inside loop introduces extra "list_empty" judgement than original
> patch. But personally I prefer the newer version too:
> 
> Signed-off-by: Hong Zhiguo <honkiko@gmail.com>

Please don't submit patches like this:

1) When submitting new versions of a patch, make a fresh
   new mailing list posting with just the patch and it's
   commit message.

   Do not post new versions by replying to other conversations.

2) Your email client has severely corrupted the patch, breaking
   up long lines etc.  Please read Documentation/email-clients.txt
   to learn how to fix this.
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diff mbox

Patch

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 2ee56de..0737bd4 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -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 */