Date: Wed, 6 Jun 2012 23:16:20 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>,
        Jason Wang <jasowang@redhat.com>, netdev@vger.kernel.org,
        rusty@rustcorp.com.au, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org
Subject: Re: [PATCH] virtio-net: fix a race on 32bit arches
Message-ID: <20120606201620.GA23358@redhat.com>
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On Wed, Jun 06, 2012 at 10:08:09PM +0200, Eric Dumazet wrote:
> On Wed, 2012-06-06 at 22:58 +0300, Michael S. Tsirkin wrote:
> 
> > Absolutely, I am talking about virtio here.  I'm not kicking
> > u64_stats_sync idea I am just saying that simple locking
> > would work for virtio and might be better as it
> > gives us a way to get counters atomically.
> 
> Which lock do you own in the RX path ?

We can just disable napi, everything is updated from napi callback.

> You'll have to add a lock in fast path. This sounds really a bad choice
> to me.

.ndo_get_stats64 is not data path though, is it?

-- 
MST
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