From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 95F9CC43215 for ; Tue, 26 Nov 2019 23:57:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70E692064A for ; Tue, 26 Nov 2019 23:57:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726975AbfKZX5s (ORCPT ); Tue, 26 Nov 2019 18:57:48 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:44282 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726380AbfKZX5s (ORCPT ); Tue, 26 Nov 2019 18:57:48 -0500 Received: from localhost (c-73-35-209-67.hsd1.wa.comcast.net [73.35.209.67]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 7F33914DDDEC8; Tue, 26 Nov 2019 15:57:46 -0800 (PST) Date: Tue, 26 Nov 2019 15:57:46 -0800 (PST) Message-Id: <20191126.155746.627765091618337419.davem@davemloft.net> To: alobakin@dlink.ru Cc: pabeni@redhat.com, johannes@sipsolutions.net, ecree@solarflare.com, nicholas.johnson-opensource@outlook.com.au, jiri@mellanox.com, edumazet@google.com, idosch@mellanox.com, petrm@mellanox.com, sd@queasysnail.net, f.fainelli@gmail.com, jaswinder.singh@linaro.org, ilias.apalodimas@linaro.org, linux-kernel@vger.kernel.org, emmanuel.grumbach@intel.com, luciano.coelho@intel.com, linuxwifi@intel.com, kvalo@codeaurora.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org Subject: Re: [PATCH v2 net-next] net: core: use listified Rx for GRO_NORMAL in napi_gro_receive() From: David Miller In-Reply-To: References: <414288fcac2ba4fcee48a63bdbf28f7b9a5037c6.camel@sipsolutions.net> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 26 Nov 2019 15:57:47 -0800 (PST) Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Alexander Lobakin Date: Mon, 25 Nov 2019 15:02:24 +0300 > Paolo Abeni wrote 25.11.2019 14:42: >> For -net, I *think* something as dumb and hacky as the following could >> possibly work: >> ---- >> diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c >> b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c >> index 4bba6b8a863c..df82fad96cbb 100644 >> --- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c >> +++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c >> @@ -1527,7 +1527,7 @@ static void iwl_pcie_rx_handle(struct iwl_trans >> *trans, int queue) >> iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq); >> if (rxq->napi.poll) >> - napi_gro_flush(&rxq->napi, false); >> + napi_complete_done(&rxq->napi, 0); >> iwl_pcie_rxq_restock(trans, rxq); >> } >> --- > > napi_complete_done(napi, 0) has an equivalent static inline > napi_complete(napi). I'm not sure it will work without any issues > as iwlwifi doesn't _really_ turn NAPI into scheduling state. > > I'm not very familiar with iwlwifi, but as a work around manual > napi_gro_flush() you can also manually flush napi->rx_list to > prevent packets from stalling: > > diff -Naur a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c > b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c > --- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c 2019-11-25 > --- 14:55:03.610355230 +0300 > +++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c 2019-11-25 > 14:57:29.399556868 +0300 ... Thanks to everyone for looking into this. Can I get some kind of fix in the next 24 hours? I want to send a quick follow-on pull request to Linus to deal with all of the fallout, and in particular fix this regression. Thanks!