From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [RFC PATCH] Regression in linux 2.6.32 virtio_net seen with
	vhost-net
Date: Wed, 16 Dec 2009 15:38:07 +0200
Message-ID: <20091216133806.GB29522@redhat.com>
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Cc: Rusty Russell <rusty@rustcorp.com.au>,
	Sridhar Samudrala <sri@us.ibm.com>, netdev@vger.kernel.org
To: Herbert Xu <herbert@gondor.apana.org.au>
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On Wed, Dec 16, 2009 at 09:35:12PM +0800, Herbert Xu wrote:
> On Wed, Dec 16, 2009 at 03:22:18PM +0200, Michael S. Tsirkin wrote:
> >
> > Doesn't netif_stop_queue include an atomic op?
> > If yes, does not atomic imply wmb already?
> 
> Unfortunately it doesn't.

So do we need an rmb after testing it as well?
Lock would be simpler :)

> Cheers,
> -- 
> Visit Openswan at http://www.openswan.org/
> Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
> Home Page: http://gondor.apana.org.au/~herbert/
> PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt