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=-9.9 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 169E5C43461 for ; Tue, 8 Sep 2020 21:35:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBBFD2075A for ; Tue, 8 Sep 2020 21:35:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728483AbgIHVfi (ORCPT ); Tue, 8 Sep 2020 17:35:38 -0400 Received: from dispatch1-us1.ppe-hosted.com ([67.231.154.164]:43482 "EHLO dispatch1-us1.ppe-hosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726490AbgIHVff (ORCPT ); Tue, 8 Sep 2020 17:35:35 -0400 Received: from mx1-us1.ppe-hosted.com (unknown [10.110.50.143]) by dispatch1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTP id 407E8200C8; Tue, 8 Sep 2020 21:35:33 +0000 (UTC) Received: from us4-mdac16-57.at1.mdlocal (unknown [10.110.50.149]) by mx1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTP id 3E7538009B; Tue, 8 Sep 2020 21:35:33 +0000 (UTC) X-Virus-Scanned: Proofpoint Essentials engine Received: from mx1-us1.ppe-hosted.com (unknown [10.110.49.6]) by mx1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTPS id C04CC40072; Tue, 8 Sep 2020 21:35:32 +0000 (UTC) Received: from webmail.solarflare.com (uk.solarflare.com [193.34.186.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mx1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTPS id 7ED40B00080; Tue, 8 Sep 2020 21:35:32 +0000 (UTC) Received: from [10.17.20.203] (10.17.20.203) by ukex01.SolarFlarecom.com (10.17.10.4) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 8 Sep 2020 22:35:25 +0100 Subject: Re: [PATCH 5.4 086/129] net: core: use listified Rx for GRO_NORMAL in napi_gro_receive() To: Greg Kroah-Hartman , CC: , Alexander Lobakin , "David S. Miller" , Hyunsoon Kim References: <20200908152229.689878733@linuxfoundation.org> <20200908152234.000867723@linuxfoundation.org> From: Edward Cree Message-ID: <70529b6c-7b00-d760-c0c0-42f0ea5784f3@solarflare.com> Date: Tue, 8 Sep 2020 22:35:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20200908152234.000867723@linuxfoundation.org> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Content-Language: en-GB X-Originating-IP: [10.17.20.203] X-ClientProxiedBy: ocex03.SolarFlarecom.com (10.20.40.36) To ukex01.SolarFlarecom.com (10.17.10.4) X-TM-AS-Product-Ver: SMEX-12.5.0.1300-8.6.1012-25652.007 X-TM-AS-Result: No-1.974400-8.000000-10 X-TMASE-MatchedRID: zGP2F0O7j/v4ECMHJTM/ufZvT2zYoYOwC/ExpXrHizwZFDQxUvPcmL6Y VRYkPkYCSCF6HRRH3gIN25tj8sME0lpGtZpuPG16tKV49RpAH3tOxMIe1e/Q+lT4wXE1Q3+tocP Vrs+9l2WrarPPtIvi4uYoVJQ9TcQivz6xGurTfloBnSWdyp4eoWgU1o1xV13fYcgF3TR2TfI5pz FMSqNkwrysmJ3Ri+UacaFM17gO4IyR9GF2J2xqM4MbH85DUZXyseWplitmp0j6C0ePs7A07Sib6 hcH39TzeqiyYsWDasnfZjOmAfXU7ARUs+MuSyMTpgHjzELc15CjObMcXmcytw5LZNIb/Wv0bMa8 YIGFldTr/ToUHXs83CgS77Whwf5LUdNvZjjOj9C63BPMcrcQuXeYWV2RaAfD8VsfdwUmMsnAvpL E+mvX8g== X-TM-AS-User-Approved-Sender: Yes X-TM-AS-User-Blocked-Sender: No X-TMASE-Result: 10--1.974400-8.000000 X-TMASE-Version: SMEX-12.5.0.1300-8.6.1012-25652.007 X-MDID: 1599600933-oajcFjSGPQmL Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/09/2020 16:25, Greg Kroah-Hartman wrote: > From: Alexander Lobakin > > commit 6570bc79c0dfff0f228b7afd2de720fb4e84d61d upstream. > > Commit 323ebb61e32b4 ("net: use listified RX for handling GRO_NORMAL > skbs") made use of listified skb processing for the users of > napi_gro_frags(). > The same technique can be used in a way more common napi_gro_receive() > to speed up non-merged (GRO_NORMAL) skbs for a wide range of drivers > including gro_cells and mac80211 users. > This slightly changes the return value in cases where skb is being > dropped by the core stack, but it seems to have no impact on related > drivers' functionality. > gro_normal_batch is left untouched as it's very individual for every > single system configuration and might be tuned in manual order to > achieve an optimal performance. > > Signed-off-by: Alexander Lobakin > Acked-by: Edward Cree > Signed-off-by: David S. Miller > Signed-off-by: Hyunsoon Kim > Signed-off-by: Greg Kroah-Hartman I'm not quite sure why this is stable material(it's a performance  enhancement, rather than a fix).  But if you do want to take it,  make sure you've also got c80794323e82 ("net: Fix packet reordering caused by GRO and listified RX cooperation") b167191e2a85 ("net: wireless: intel: iwlwifi: fix GRO_NORMAL packet stalling")  in your tree, particularly the latter as without it this commit  triggers a severe regression in iwlwifi. -ed