From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751861AbdHQDhr (ORCPT ); Wed, 16 Aug 2017 23:37:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52936 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751552AbdHQDhq (ORCPT ); Wed, 16 Aug 2017 23:37:46 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 11CBBC00BB28 Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=jasowang@redhat.com Subject: Re: [PATCH] tun: make tun_build_skb() thread safe To: "Michael S. Tsirkin" Cc: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Dumazet References: <1502892873-10770-1-git-send-email-jasowang@redhat.com> <20170816195342-mutt-send-email-mst@kernel.org> From: Jason Wang Message-ID: <13d6f0f3-62e1-d760-7504-341d420fa593@redhat.com> Date: Thu, 17 Aug 2017 11:37:35 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20170816195342-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Thu, 17 Aug 2017 03:37:46 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017年08月17日 00:55, Michael S. Tsirkin wrote: > On Wed, Aug 16, 2017 at 10:14:33PM +0800, Jason Wang wrote: >> From: Eric Dumazet >> >> tun_build_skb() is not thread safe since it uses per queue page frag, >> this will break things when multiple threads are sending through same >> queue. Switch to use per-thread generator (no lock involved). >> >> Fixes: 66ccbc9c87c2 ("tap: use build_skb() for small packet") >> Tested-by: Jason Wang >> Signed-off-by: Eric Dumazet >> Signed-off-by: Jason Wang > Acked-by: Michael S. Tsirkin > > Jason, given the switch to task_frag, would it be worth it to look at > using higher order allocs along the lines of > 5640f7685831e088fe6c2e1f863a6805962f8e81 as well? > I think we've already used high order, don't we? Thanks