Date: Thu, 2 Apr 2009 17:16:39 +0800
From: Herbert Xu <herbert@gondor.apana.org.au>
To: Avi Kivity <avi@redhat.com>
Cc: ghaskins@novell.com, anthony@codemonkey.ws, andi@firstfloor.org,
       linux-kernel@vger.kernel.org, agraf@suse.de, pmullaney@novell.com,
       pmorreale@novell.com, rusty@rustcorp.com.au, netdev@vger.kernel.org,
       kvm@vger.kernel.org
Subject: Re: [RFC PATCH 00/17] virtual-bus
Message-ID: <20090402091639.GA30126@gondor.apana.org.au>
References: <20090402085253.GA29932@gondor.apana.org.au> <49D47F11.6070400@redhat.com>
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On Thu, Apr 02, 2009 at 12:02:09PM +0300, Avi Kivity wrote:
>
> There is no choice.  Exiting from the guest to the kernel to userspace  
> is prohibitively expensive, you can't do that on every packet.

I was referring to the bit between the kernel and userspace.

In any case, I just looked at the virtio mitigation code again
and I am completely baffled at why we need it.  Look at Greg's
code or the netback/netfront notification, why do we need this
completely artificial mitigation when the ring itself provides
a natural way of stemming the flow?

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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