From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: [RFC PATCH net-next v6 4/4] netvsc: refactor notifier/event handling code to use the bypass framework Date: Wed, 11 Apr 2018 09:50:20 +0200 Message-ID: <20180411075020.GJ2028@nanopsycho> References: <1523386790-12396-1-git-send-email-sridhar.samudrala@intel.com> <1523386790-12396-5-git-send-email-sridhar.samudrala@intel.com> <20180410142608.50f15b45@xeon-e3> <20180411022807-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Stephen Hemminger , Sridhar Samudrala , davem@davemloft.net, netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org, jesse.brandeburg@intel.com, alexander.h.duyck@intel.com, kubakici@wp.pl, jasowang@redhat.com, loseweigh@gmail.com To: "Michael S. Tsirkin" Return-path: Received: from mail-wm0-f67.google.com ([74.125.82.67]:54187 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730AbeDKHuW (ORCPT ); Wed, 11 Apr 2018 03:50:22 -0400 Received: by mail-wm0-f67.google.com with SMTP id 66so2112515wmd.3 for ; Wed, 11 Apr 2018 00:50:22 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20180411022807-mutt-send-email-mst@kernel.org> Sender: netdev-owner@vger.kernel.org List-ID: Wed, Apr 11, 2018 at 01:28:51AM CEST, mst@redhat.com wrote: >On Tue, Apr 10, 2018 at 02:26:08PM -0700, Stephen Hemminger wrote: >> On Tue, 10 Apr 2018 11:59:50 -0700 >> Sridhar Samudrala wrote: >> >> > Use the registration/notification framework supported by the generic >> > bypass infrastructure. >> > >> > Signed-off-by: Sridhar Samudrala >> > --- >> >> Thanks for doing this. Your current version has couple show stopper >> issues. >> >> First, the slave device is instantly taking over the slave. >> This doesn't allow udev/systemd to do its device rename of the slave >> device. Netvsc uses a delayed work to workaround this. > >Interesting. Does this mean udev must act within a specific time window >then? Yeah. That is scarry. Also, wrong. > >> Secondly, the select queue needs to call queue selection in VF. >> The bonding/teaming logic doesn't work well for UDP flows. >> Commit b3bf5666a510 ("hv_netvsc: defer queue selection to VF") >> fixed this performance problem. >> >> Lastly, more indirection is bad in current climate. >> >> I am not completely adverse to this but it needs to be fast, simple >> and completely transparent.