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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 D25BDC43381 for ; Mon, 25 Mar 2019 09:35:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A16DB20863 for ; Mon, 25 Mar 2019 09:35:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=nbd.name header.i=@nbd.name header.b="LE7BsDA9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730358AbfCYJfl (ORCPT ); Mon, 25 Mar 2019 05:35:41 -0400 Received: from nbd.name ([46.4.11.11]:41478 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730304AbfCYJfl (ORCPT ); Mon, 25 Mar 2019 05:35:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=nbd.name; s=20160729; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=rQe/l9mgvCqTL9mhA2/4Rw33VNqH8CH0slTS/RZc1DM=; b=LE7BsDA9GK4ZkBQFGbsIs64dvD d+xtftFdG2PjDuIQwBdZz7SrrXIVG1lZz6pT6YkSw9V1ty6vBE4K/lS/oxua5auA1ZoPlWPbggjoy BJBhcAQdGkOSUOucqKZoJiCfgmirC7+PY4OcWkQIqWMaHNlQWYOkKbc+kaXRpO2cjgDg=; Received: from p4ff13338.dip0.t-ipconnect.de ([79.241.51.56] helo=nf.local) by ds12 with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1h8M12-0006aj-Cd; Mon, 25 Mar 2019 10:35:36 +0100 Subject: Re: [PATCH v2] net: use bulk free in kfree_skb_list To: Eric Dumazet , netdev@vger.kernel.org Cc: davem@davemloft.net, brouer@redhat.com, fw@strlen.de References: <20190324165644.21303-1-nbd@nbd.name> <3d7fd814-9525-f0a6-95ff-cccc2de8ecd8@gmail.com> <283cb1b7-dc83-04fd-15c0-b4bfd2411cbc@nbd.name> <37b3be81-f86d-3805-10d3-177e66d8d8f7@gmail.com> From: Felix Fietkau Openpgp: preference=signencrypt Autocrypt: addr=nbd@nbd.name; prefer-encrypt=mutual; keydata= mQGiBEah5CcRBADIY7pu4LIv3jBlyQ/2u87iIZGe6f0f8pyB4UjzfJNXhJb8JylYYRzIOSxh ExKsdLCnJqsG1PY1mqTtoG8sONpwsHr2oJ4itjcGHfn5NJSUGTbtbbxLro13tHkGFCoCr4Z5 Pv+XRgiANSpYlIigiMbOkide6wbggQK32tC20QxUIwCg4k6dtV/4kwEeiOUfErq00TVqIiEE AKcUi4taOuh/PQWx/Ujjl/P1LfJXqLKRPa8PwD4j2yjoc9l+7LptSxJThL9KSu6gtXQjcoR2 vCK0OeYJhgO4kYMI78h1TSaxmtImEAnjFPYJYVsxrhay92jisYc7z5R/76AaELfF6RCjjGeP wdalulG+erWju710Bif7E1yjYVWeA/9Wd1lsOmx6uwwYgNqoFtcAunDaMKi9xVQW18FsUusM TdRvTZLBpoUAy+MajAL+R73TwLq3LnKpIcCwftyQXK5pEDKq57OhxJVv1Q8XkA9Dn1SBOjNB l25vJDFAT9ntp9THeDD2fv15yk4EKpWhu4H00/YX8KkhFsrtUs69+vZQwbQcRmVsaXggRmll dGthdSA8bmJkQG5iZC5uYW1lPohgBBMRAgAgBQJGoeQnAhsjBgsJCAcDAgQVAggDBBYCAwEC HgECF4AACgkQ130UHQKnbvXsvgCgjsAIIOsY7xZ8VcSm7NABpi91yTMAniMMmH7FRenEAYMa VrwYTIThkTlQuQINBEah5FQQCACMIep/hTzgPZ9HbCTKm9xN4bZX0JjrqjFem1Nxf3MBM5vN CYGBn8F4sGIzPmLhl4xFeq3k5irVg/YvxSDbQN6NJv8o+tP6zsMeWX2JjtV0P4aDIN1pK2/w VxcicArw0VYdv2ZCarccFBgH2a6GjswqlCqVM3gNIMI8ikzenKcso8YErGGiKYeMEZLwHaxE Y7mTPuOTrWL8uWWRL5mVjhZEVvDez6em/OYvzBwbkhImrryF29e3Po2cfY2n7EKjjr3/141K DHBBdgXlPNfDwROnA5ugjjEBjwkwBQqPpDA7AYPvpHh5vLbZnVGu5CwG7NAsrb2isRmjYoqk wu++3117AAMFB/9S0Sj7qFFQcD4laADVsabTpNNpaV4wAgVTRHKV/kC9luItzwDnUcsZUPdQ f3MueRJ3jIHU0UmRBG3uQftqbZJj3ikhnfvyLmkCNe+/hXhPu9sGvXyi2D4vszICvc1KL4RD aLSrOsROx22eZ26KqcW4ny7+va2FnvjsZgI8h4sDmaLzKczVRIiLITiMpLFEU/VoSv0m1F4B FtRgoiyjFzigWG0MsTdAN6FJzGh4mWWGIlE7o5JraNhnTd+yTUIPtw3ym6l8P+gbvfoZida0 TspgwBWLnXQvP5EDvlZnNaKa/3oBes6z0QdaSOwZCRA3QSLHBwtgUsrT6RxRSweLrcabiEkE GBECAAkFAkah5FQCGwwACgkQ130UHQKnbvW2GgCfTKx80VvCR/PvsUlrvdOLsIgeRGAAn1ee RjMaxwtSdaCKMw3j33ZbsWS4 Message-ID: Date: Mon, 25 Mar 2019 10:35:35 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.6.0 MIME-Version: 1.0 In-Reply-To: <37b3be81-f86d-3805-10d3-177e66d8d8f7@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2019-03-25 10:31, Eric Dumazet wrote: > > > On 03/25/2019 02:09 AM, Felix Fietkau wrote: >> On 2019-03-25 09:51, Eric Dumazet wrote: >>> >>> >>> On 03/24/2019 09:56 AM, Felix Fietkau wrote: >>>> Since we're freeing multiple skbs, we might as well use bulk free to save a >>>> few cycles. Use the same conditions for bulk free as in napi_consume_skb. >>>> >>> >>> I do not believe kfree_skb_list() is used in the fast path, so do we really >>> need to make it so complex ? >> mac80211 uses it to free the fraglist from A-MSDU aggregated packets in >> the tx status path. That's one fast path where it gets used right now >> and the reason it was showing up in my perf traces. > > This is not drop monitor friendly then.... > > TX completion should use consume_skb() or dev_kfree_skb() > > BTW, I wonder what drop-monitor signal bulk free is sending ? Good point about the drop monitor. Would you prefer that I replace this patch with one that adds a consume_skb_list function and another one that makes mac80211 use it? - Felix