[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <49D4BD50.4070402@redhat.com>
Date: Thu, 02 Apr 2009 16:27:44 +0300
From: Avi Kivity <avi@...hat.com>
To: Gregory Haskins <ghaskins@...ell.com>
CC: Rusty Russell <rusty@...tcorp.com.au>,
Herbert Xu <herbert@...dor.apana.org.au>,
anthony@...emonkey.ws, andi@...stfloor.org,
linux-kernel@...r.kernel.org, agraf@...e.de, pmullaney@...ell.com,
pmorreale@...ell.com, netdev@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [RFC PATCH 00/17] virtual-bus
Gregory Haskins wrote:
> Avi Kivity wrote:
>
>> Gregory Haskins wrote:
>>
>>> Rusty Russell wrote:
>>>
>>>
>>>> On Thursday 02 April 2009 21:36:07 Gregory Haskins wrote:
>>>>
>>>>
>>>>> You do not need to know when the packet is copied (which I currently
>>>>> do). You only need it for zero-copy (of which I would like to
>>>>> support,
>>>>> but as I understand it there are problems with the reliability of
>>>>> proper
>>>>> callback (i.e. skb->destructor).
>>>>>
>>>>>
>>>> But if you have a UP guest,
>>>>
>>>>
>>> I assume you mean UP host ;)
>>>
>>>
>>>
>> I think Rusty did mean a UP guest, and without schedule-and-forget.
>>
> That doesnt make sense to me, tho. All the testing I did was a UP
> guest, actually. Why would I be constrained to run without the
> scheduling unless the host was also UP?
>
You aren't constrained. And your numbers show it works.
>>
>> The problem is that we already have virtio guest drivers going several
>> kernel versions back, as well as Windows drivers. We can't keep
>> changing the infrastructure under people's feet.
>>
>
> Well, IIUC the virtio code itself declares the ABI as unstable, so there
> technically *is* an out if we really wanted one. But I certainly
> understand the desire to not change this ABI if at all possible, and
> thus the resistance here.
>
virtio is a stable ABI.
> However, theres still the possibility we can make this work in an ABI
> friendly way with cap-bits, or other such features. For instance, the
> virtio-net driver could register both with pci and vbus-proxy and
> instantiate a device with a slightly different ops structure for each or
> something. Alternatively we could write a host-side shim to expose vbus
> devices as pci devices or something like that.
>
Sounds complicated...
--
error compiling committee.c: too many arguments to function
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists