From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 6B4AB5A24 for ; Tue, 22 Dec 2015 06:45:59 +0100 (CET) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP; 21 Dec 2015 21:45:58 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,463,1444719600"; d="scan'208";a="867003303" Received: from yliu-dev.sh.intel.com (HELO yliu-dev) ([10.239.66.49]) by fmsmga001.fm.intel.com with ESMTP; 21 Dec 2015 21:45:57 -0800 Date: Tue, 22 Dec 2015 13:47:10 +0800 From: Yuanhan Liu To: Rich Lane Message-ID: <20151222054710.GK18863@yliu-dev.sh.intel.com> References: <1447392031-24970-3-git-send-email-mukawa@igel.co.jp> <1448355603-21275-1-git-send-email-mukawa@igel.co.jp> <1448355603-21275-2-git-send-email-mukawa@igel.co.jp> <20151217114223.GC29571@yliu-dev.sh.intel.com> <56737A5E.1030803@igel.co.jp> <20151218041536.GI29571@yliu-dev.sh.intel.com> <56738B5C.1030206@igel.co.jp> <20151222034158.GH18863@yliu-dev.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Cc: dev@dpdk.org, ann.zhuangyanying@huawei.com Subject: Re: [dpdk-dev] [PATCH v5 1/3] vhost: Add callback and private data for vhost PMD X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Dec 2015 05:46:00 -0000 On Mon, Dec 21, 2015 at 08:47:28PM -0800, Rich Lane wrote: > On Mon, Dec 21, 2015 at 7:41 PM, Yuanhan Liu > wrote: > > On Fri, Dec 18, 2015 at 10:01:25AM -0800, Rich Lane wrote: > > I'm using the vhost callbacks and struct virtio_net with the vhost PMD in > a few > > ways: > > Rich, thanks for the info! > > > > > 1. new_device/destroy_device: Link state change (will be covered by the > link > > status interrupt). > > 2. new_device: Add first queue to datapath. > > I'm wondering why vring_state_changed() is not used, as it will also be > triggered at the beginning, when the default queue (the first queue) is > enabled. > > > Turns out I'd misread the code and it's already using the vring_state_changed > callback for the > first queue. Not sure if this is intentional but vring_state_changed is called > for the first queue > before new_device. Yeah, you were right, we can't count on this vring_state_changed(), for it's sent earlier than vring has been initialized on vhost side. Maybe we should invoke vring_state_changed() callback at new_device() as well. >   > > > 3. vring_state_changed: Add/remove queue to datapath. > > 4. destroy_device: Remove all queues (vring_state_changed is not called > when > > qemu is killed). > > I had a plan to invoke vring_state_changed() to disable all vrings > when destroy_device() is called. > > > That would be good. >   > > > 5. new_device and struct virtio_net: Determine NUMA node of the VM. > > You can get the 'struct virtio_net' dev from all above callbacks. > >   > > > 1. Link status interrupt. > > To vhost pmd, new_device()/destroy_device() equals to the link status > interrupt, where new_device() is a link up, and destroy_device() is link > down(). > > > > 2. New queue_state_changed callback. Unlike vring_state_changed this > should > > cover the first queue at new_device and removal of all queues at > > destroy_device. > > As stated above, vring_state_changed() should be able to do that, except > the one on destroy_device(), which is not done yet. > > > 3. Per-queue or per-device NUMA node info. > > You can query the NUMA node info implicitly by get_mempolicy(); check > numa_realloc() at lib/librte_vhost/virtio-net.c for reference. > > > Your suggestions are exactly how my application is already working. I was > commenting on the > proposed changes to the vhost PMD API. I would prefer to > use RTE_ETH_EVENT_INTR_LSC > and rte_eth_dev_socket_id for consistency with other NIC drivers, instead of > these vhost-specific > hacks. That's a good suggestion. > The queue state change callback is the one new API that needs to be > added because > normal NICs don't have this behavior. Again I'd ask, will vring_state_changed() be enough, when above issues are resolved: vring_state_changed() will be invoked at new_device()/ destroy_device(), and of course, ethtool change? --yliu > > You could add another rte_eth_event_type for the queue state change callback, > and pass the > queue ID, RX/TX direction, and enable bit through cb_arg. The application would > never need > to touch struct virtio_net.