From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH 4/6] virtio network driver
Date: Sun, 30 Mar 2008 10:27:07 +0000
Message-ID: <200803301127.08620.paul@codesourcery.com>
References: <1206827760-4566-1-git-send-email-aliguori@us.ibm.com>
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Cc: kvm-devel@lists.sourceforge.net,
	Marcelo Tosatti <marcelo@kvack.org>,
	Aurelien Jarno <aurelien@aurel32.net>
To: qemu-devel@nongnu.org
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On Saturday 29 March 2008, Anthony Liguori wrote:
> + =A0 =A0if ((elem =3D virtqueue_pop(n->rx_vq)) =3D=3D NULL) {
> +=A0=A0=A0=A0=A0=A0=A0/* wait until the guest adds some rx bufs */
> +=A0=A0=A0=A0=A0=A0=A0n->can_receive =3D 0;
> +=A0=A0=A0=A0=A0=A0=A0return;
> + =A0 =A0}

Setting can_receive to zero *after* dropping a packet is a bit late.
Not a fatal flaw, but it does make can_receive fairly useless. The whole po=
int =

of can_receive is to workaround lack of proper TCP rate control in the slir=
p =

code.

Paul

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