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Date: Wed, 5 May 2010 14:09:47 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20100505110947.GA27872@redhat.com>
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Subject: [Qemu-devel] question on virtio
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To: Rusty Russell <rusty@rustcorp.com.au>
Cc: kvm@vger.kernel.org, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org

Hi!
I see this in virtio_ring.c:

        /* Put entry in available array (but don't update avail->idx *
	   until they do sync). */

Why is it done this way?
It seems that updating the index straight away would be simpler, while
this might allow the host to specilatively look up the buffer and handle
it, without waiting for the kick.

-- 
MST