From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shirley Ma <mashirle@us.ibm.com>
Subject: Re: [PATCH V7 4/4 net-next] vhost: vhost TX zero-copy support
Date: Thu, 30 Jun 2011 09:05:22 -0700
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Cc: David Miller <davem@davemloft.net>,
	Eric Dumazet <eric.dumazet@gmail.com>,
	Avi Kivity <avi@redhat.com>, Arnd Bergmann <arnd@arndb.de>,
	netdev@vger.kernel.org, kvm@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Wed, 2011-06-29 at 12:13 +0300, Michael S. Tsirkin wrote:
> Assuming you mean vhost_zerocopy_signal_used, here's how I would do
> it:
> add a kref and a completion, signal completion in kref_put
> callback, when backend is set - kref_get, on cleanup,
> kref_put and then wait_for_completion_interruptible.
> Where's the need for another thread coming from?
> 
> If you like, post a patch with busywait + a FIXME comment,
> and I can write up a patch on top.
> 
> (BTW, ideally the function that does the signalling should be
> in core networking bits so that it's still around
> even if the vhost module gets removed). 

OK, I will modify the patch.

Thanks
Shirley