From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] hv_netvsc: remove ndo_poll_controller Date: Tue, 02 Oct 2018 22:57:59 -0700 (PDT) Message-ID: <20181002.225759.1657914781928636887.davem@davemloft.net> References: <20180929125256.25994-1-sthemmin@microsoft.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, sthemmin@microsoft.com, haiyangz@microsoft.com, edumazet@google.com To: stephen@networkplumber.org Return-path: Received: from shards.monkeyblade.net ([23.128.96.9]:55010 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726432AbeJCMow (ORCPT ); Wed, 3 Oct 2018 08:44:52 -0400 In-Reply-To: <20180929125256.25994-1-sthemmin@microsoft.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Stephen Hemminger Date: Sat, 29 Sep 2018 14:52:56 +0200 > Similar to other patches from ERic. > > As diagnosed by Song Liu, ndo_poll_controller() can > be very dangerous on loaded hosts, since the cpu > calling ndo_poll_controller() might steal all NAPI > contexts (for all RX/TX queues of the NIC). This capture > can last for unlimited amount of time, since one > cpu is generally not able to drain all the queues under load. > > In netvsc driver it uses NAPI for TX completions. The default > poll_napi will do this for us now and avoid the capture. > > Signed-off-by: Stephen Hemminger Applied to net-next.