From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tiwei Bie Subject: Re: Re: [PATCH net-next v2 0/5] virtio: support packed ring Date: Thu, 11 Oct 2018 22:34:43 +0800 Message-ID: <20181011143443.GA18183@debian> References: <20180911053726.GA7472@debian> <20180912121457-mutt-send-email-mst@kernel.org> <20180913085919.GA42049@fbsd1.sh.intel.com> <98d6bd4d-45e2-4207-e961-782f649e0139@redhat.com> <20181010103335-mutt-send-email-mst@kernel.org> <20181011121221.GA27106@debian> <20181011094705-mutt-send-email-mst@kernel.org> <20181011141331.GA11650@debian> <20181011101656-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Jason Wang , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, virtio-dev@lists.oasis-open.org, wexu@redhat.com, jfreimann@redhat.com, maxime.coquelin@redhat.com, zhihong.wang@intel.com To: "Michael S. Tsirkin" Return-path: Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Content-Disposition: inline In-Reply-To: <20181011101656-mutt-send-email-mst@kernel.org> List-Id: netdev.vger.kernel.org On Thu, Oct 11, 2018 at 10:17:15AM -0400, Michael S. Tsirkin wrote: > On Thu, Oct 11, 2018 at 10:13:31PM +0800, Tiwei Bie wrote: > > On Thu, Oct 11, 2018 at 09:48:48AM -0400, Michael S. Tsirkin wrote: > > > On Thu, Oct 11, 2018 at 08:12:21PM +0800, Tiwei Bie wrote: > > > > > > But if it's not too late, I second for a OUT_OF_ORDER feature. > > > > > > Starting from in order can have much simpler code in driver. > > > > > > > > > > > > Thanks > > > > > > > > > > It's tricky to change the flag polarity because of compatibility > > > > > with legacy interfaces. Why is this such a big deal? > > > > > > > > > > Let's teach drivers about IN_ORDER, then if devices > > > > > are in order it will get enabled by default. > > > > > > > > Yeah, make sense. > > > > > > > > Besides, I have done some further profiling and debugging > > > > both in kernel driver and DPDK vhost. Previously I was mislead > > > > by a bug in vhost code. I will send a patch to fix that bug. > > > > With that bug fixed, the performance of packed ring in the > > > > test between kernel driver and DPDK vhost is better now. > > > > > > OK, if we get a performance gain on the virtio side, we can finally > > > upstream it. If you see that please re-post ASAP so we can > > > put it in the next kernel release. > > > > Got it, I will re-post ASAP. > > > > Thanks! > > > Pls remember to include data on performance gain in the cover letter. Sure. I'll try to include some performance analyses.