From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH v5 1/3] vhost: Add callback and private data for vhost PMD Date: Wed, 23 Dec 2015 23:00:15 +0100 Message-ID: <1689693.Nk6ErSWZrF@xps13> References: <1448355603-21275-2-git-send-email-mukawa@igel.co.jp> <20151223024453.GW18863@yliu-dev.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, ann.zhuangyanying@huawei.com To: Yuanhan Liu Return-path: Received: from mail-wm0-f49.google.com (mail-wm0-f49.google.com [74.125.82.49]) by dpdk.org (Postfix) with ESMTP id 845865A87 for ; Wed, 23 Dec 2015 23:01:49 +0100 (CET) Received: by mail-wm0-f49.google.com with SMTP id p187so163994270wmp.0 for ; Wed, 23 Dec 2015 14:01:49 -0800 (PST) In-Reply-To: <20151223024453.GW18863@yliu-dev.sh.intel.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 2015-12-23 10:44, Yuanhan Liu: > On Tue, Dec 22, 2015 at 01:38:29AM -0800, Rich Lane wrote: > > On Mon, Dec 21, 2015 at 9:47 PM, Yuanhan Liu > > wrote: > > > > On Mon, Dec 21, 2015 at 08:47:28PM -0800, Rich Lane wrote: > > > 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? > > > > > > It would be sufficient. It is not a great API though, because it requires the > > application to do the conversion from struct virtio_net to a DPDK port number, > > and from a virtqueue index to a DPDK queue id and direction. Also, the current > > implementation often makes this callback when the vring state has not actually > > changed (enabled -> enabled and disabled -> disabled). > > > > If you're asking about using vring_state_changed() _instead_ of the link status > > event and rte_eth_dev_socket_id(), > > No, I like the idea of link status event and rte_eth_dev_socket_id(); > I was just wondering why a new API is needed. Both Tetsuya and I > were thinking to leverage the link status event to represent the > queue stats change (triggered by vring_state_changed()) as well, > so that we don't need to introduce another eth event. However, I'd > agree that it's better if we could have a new dedicate event. > > Thomas, here is some background for you. For vhost pmd and linux > virtio-net combo, the queue can be dynamically changed by ethtool, > therefore, the application wishes to have another eth event, say > RTE_ETH_EVENT_QUEUE_STATE_CHANGE, so that the application can > add/remove corresponding queue to the datapath when that happens. > What do you think of that? Yes it is an event. So I don't understand the question. What may be better than a specific rte_eth_event_type?