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Message-ID: <47EFA81D.90802@us.ibm.com>
Date: Sun, 30 Mar 2008 09:47:57 -0500
From: Anthony Liguori <aliguori@us.ibm.com>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] [PATCH 4/6] virtio network driver
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	<1206827760-4566-4-git-send-email-aliguori@us.ibm.com>
	<200803301127.08620.paul@codesourcery.com>
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To: Paul Brook <paul@codesourcery.com>
Cc: kvm-devel@lists.sourceforge.net, Marcelo Tosatti <marcelo@kvack.org>, qemu-devel@nongnu.org, Aurelien Jarno <aurelien@aurel32.net>

Paul Brook wrote:
> On Saturday 29 March 2008, Anthony Liguori wrote:
>   
>> +    if ((elem = virtqueue_pop(n->rx_vq)) == NULL) {
>> +       /* wait until the guest adds some rx bufs */
>> +       n->can_receive = 0;
>> +       return;
>> +    }
>>     
>
> 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 point 
> of can_receive is to workaround lack of proper TCP rate control in the slirp 
> code.
>   

Yeah, I should just drop the can_receive handler.  I assumed when I 
wrote the driver originally that can_receive queued packets.  Since we 
have to drop packets anyway in the code now, there's no point in having 
a can_receive handler.

Regards,

Anthony Liguori

> Paul
>