lkml.org 
[lkml]   [2010]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRE: [PATCH v15 00/17] Provide a zero-copy method on KVM virtio-net.
>-----Original Message-----
>From: David Miller [mailto:davem@davemloft.net]
>Sent: Thursday, November 11, 2010 1:47 AM
>To: Xin, Xiaohui
>Cc: netdev@vger.kernel.org; kvm@vger.kernel.org; linux-kernel@vger.kernel.org;
>mst@redhat.com; mingo@elte.hu; herbert@gondor.apana.org.au; jdike@linux.intel.com
>Subject: Re: [PATCH v15 00/17] Provide a zero-copy method on KVM virtio-net.
>
>From: xiaohui.xin@intel.com
>Date: Wed, 10 Nov 2010 17:23:28 +0800
>
>> From: Xin Xiaohui <xiaohui.xin@intel.com>
>>
>>>2) The idea to key off of skb->dev in skb_release_data() is
>>> fundamentally flawed since many actions can change skb->dev on you,
>>> which will end up causing a leak of your external data areas.
>>
>> How about this one? If the destructor_arg is not a good candidate,
>> then I have to add an apparent field in shinfo.
>
>If destructor_arg is actually a net_device pointer or similar,
>you will need to take a reference count on it or similar.
>
Do you mean destructor_arg will be consumed by other user?
If that case, may I add a new structure member in shinfo?
Thus only zero-copy will use it, and no need for the reference count.

>Which means --> good bye performance especially on SMP.
>
>You're going to be adding new serialization points and at
>least two new atomics per packet.


\
 
 \ /
  Last update: 2010-11-11 09:31    [W:0.088 / U:4.436 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site