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=-4.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 B228AC433F5 for ; Sun, 19 Sep 2021 12:04:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9422F60F43 for ; Sun, 19 Sep 2021 12:04:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229996AbhISMGN (ORCPT ); Sun, 19 Sep 2021 08:06:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229814AbhISMGN (ORCPT ); Sun, 19 Sep 2021 08:06:13 -0400 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E627EC061574 for ; Sun, 19 Sep 2021 05:04:47 -0700 (PDT) Received: by mail-wr1-x432.google.com with SMTP id d21so23473005wra.12 for ; Sun, 19 Sep 2021 05:04:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=to:cc:references:from:subject:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=JHuxHMlOEGbwFmK1fd+3CPFdcvQmfGn79W7eRHKQ2+E=; b=NyKaouqv9WlHLw1w4Qe1R2DnBq1mXhpHPX0QR3gdozJiczILwYF6559DfgQDBUGD8I jQQnFaIlysqgK1JNsIPLAyt0JnadUGVb/kJ2grp2JPSzq4gGBAZk4P59hhcDvAn8YYz8 Ce78/4YN0qZhZWCxs6s9sioPs1MUadGQfi9gVic8/UcEpTkzdcDfVC1YMp9PefwnY7R3 jX+hvzV0knTgr4SZyR7btQPL3ov7H6eZtld8CQS9C2s4o2QTxG7rQuUitkt7AttQtLcQ rDzUnEUkjTIu4hBEEHWmBBR4woz+jVmvW12X58h2sxF0jGU2Lr4O7l9ay5QPo3+J6lpg XDRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:to:cc:references:from:subject:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=JHuxHMlOEGbwFmK1fd+3CPFdcvQmfGn79W7eRHKQ2+E=; b=AVIiyM3ZJyRMqhLwtvsO69Pn5UzNyDRCcDABHd3wMcOxKNK6fHj4uUj0xIRBYRGgpI a4IcE9Qy3MxkOH0c3SrPY5sCLOPEg+6c6tHP0/RLAkEvu2R1oZhdralC9kn4hl+0MEQp AtJTnzQEuRvqEjhzm/UcNTk3DrAepZaWQqFK1HQdo40jN9LW2/wNuBdp9XZ0I2OPd7yU sbDI/Yogq7eb4HcZqUfPP7oxetms03xvUbdkfmIuT2nwoJ8FhZVv7KSpZHbBq3c2jRLm UqA4ndWqe+1MEfqb8Va26GiDRZyu/Zq+2Rdk83yWxu9a0I4wXTxmyiMtipkPGZStcy0m XyUg== X-Gm-Message-State: AOAM530wOPyi2IRIlHIiizzIChzRFqRalXJIfeyAdAnppEKdkKAwGatW sAiDAFNj+duyTbhFCczHVsc= X-Google-Smtp-Source: ABdhPJx8s/j8nac9cSK2a3P6qCEmNZuE0R/D79UIZgh+cyesFn4lNlcjmwQIt4mCTfe8jaTMgsj1mQ== X-Received: by 2002:adf:e40b:: with SMTP id g11mr22764777wrm.313.1632053086524; Sun, 19 Sep 2021 05:04:46 -0700 (PDT) Received: from [192.168.8.197] ([148.252.128.22]) by smtp.gmail.com with ESMTPSA id d9sm15840802wrb.36.2021.09.19.05.04.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 19 Sep 2021 05:04:46 -0700 (PDT) To: Hao Xu , Jens Axboe Cc: io-uring@vger.kernel.org, Joseph Qi References: <20210917193820.224671-1-haoxu@linux.alibaba.com> <20210917193820.224671-6-haoxu@linux.alibaba.com> <2ab8efb5-7927-cf1a-a1af-f4955f7d94f6@linux.alibaba.com> From: Pavel Begunkov Subject: Re: [PATCH 5/5] io_uring: leverage completion cache for poll requests Message-ID: <166dc3e2-6eea-8354-ef12-07df49ec5aaf@gmail.com> Date: Sun, 19 Sep 2021 13:04:10 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <2ab8efb5-7927-cf1a-a1af-f4955f7d94f6@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 9/18/21 7:11 AM, Hao Xu wrote: > 在 2021/9/18 上午4:39, Pavel Begunkov 写道: >> On 9/17/21 8:38 PM, Hao Xu wrote: >>> Leverage completion cache to handle completions of poll requests in a >>> batch. >>> Good thing is we save compl_nr - 1 completion_lock and >>> io_cqring_ev_posted. >>> Bad thing is compl_nr extra ifs in flush_completion. >> >> It does something really wrong breaking all abstractions, we can't go >> with this. Can we have one of those below? >> - __io_req_complete(issue_flags), forwarding issue_flags from above >> - or maybe io_req_task_complete(), if we're in tw > Make sense. we may need to remove io_clean_op logic in > io_req_complete_state(), multishot reqs shouldn't do it, and it's ok for > normal reqs since we do it later in __io_submit_flush_completions-> > io_req_free_batch->io_dismantle_req->io_clean_op, correct me if I'm > wrong. req->compl.cflags is in the first 64B, i.e. aliased with req->rw and others. We need to clean everything left in there before using the space, that's what io_clean_op() there is for -- Pavel Begunkov