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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD911EE4996 for ; Mon, 21 Aug 2023 21:26:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229805AbjHUV0c (ORCPT ); Mon, 21 Aug 2023 17:26:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229597AbjHUV0c (ORCPT ); Mon, 21 Aug 2023 17:26:32 -0400 Received: from mail-pf1-f178.google.com (mail-pf1-f178.google.com [209.85.210.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11E6AD9; Mon, 21 Aug 2023 14:26:31 -0700 (PDT) Received: by mail-pf1-f178.google.com with SMTP id d2e1a72fcca58-68a40d8557eso1128401b3a.1; Mon, 21 Aug 2023 14:26:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692653190; x=1693257990; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=kYdThbcfPBUfAaFKHVhMtwKpLsWs6Eist/KgBO2PSlY=; b=akT5ng2e/0lx8UgWEwwgqMYUuGPOL40tP1dezkIFqGIzUnOI5cch44ZMbo5OAwFdgg PwtmMMgJs15Iw2ID8DVssJrmNZbHxYgRPz9+c6zCzAJCGol/8AXYs+XCMHWae1ov0sRA ij4cLPxC4SAA59xHfofz2lfMxznbtDh/i98pQeaLcVg98hsgVpHIw3uDfiJCpVawuD9V +Yg5dfzzCKyQhN8rk+qo+mM8NWzmFbb5MX6kJmI38qRXLFyWtk/31r894fcQoamuxb38 M6ZBG/BnyxknBm7vPufY5QXfzyf3iE6jT+AdfJ+wsHvrz4s/3qa+bPkDVamJSHOc2yRA PDTg== X-Gm-Message-State: AOJu0YzJPZb9foyoaKMUBIzljUU3sg0XfrOnpDH7FxShn95DoEKwSIv7 F7OtJBoHbk1ocBPSbEJjF4k= X-Google-Smtp-Source: AGHT+IHFiJ6TbnbMo3l/fAvwmNGMqr1Mazp/xHt1GPCte/CcOQYWGI0JIq3sR90N4ef3MnojFAveIA== X-Received: by 2002:a05:6a00:15c1:b0:684:bb4a:b86e with SMTP id o1-20020a056a0015c100b00684bb4ab86emr11738582pfu.1.1692653190273; Mon, 21 Aug 2023 14:26:30 -0700 (PDT) Received: from ?IPV6:2620:15c:211:201:ef58:6534:ec7a:8ab2? ([2620:15c:211:201:ef58:6534:ec7a:8ab2]) by smtp.gmail.com with ESMTPSA id f11-20020aa782cb000000b00688965c5227sm6558492pfn.120.2023.08.21.14.26.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 21 Aug 2023 14:26:29 -0700 (PDT) Message-ID: <98296794-01e6-7192-ef3f-0ea454527aaf@acm.org> Date: Mon, 21 Aug 2023 14:26:28 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.1 Subject: Re: [PATCH 2/4] blk-mq-tag: remove bt_for_each() Content-Language: en-US To: chengming.zhou@linux.dev, axboe@kernel.dk, ming.lei@redhat.com, hch@lst.de Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, zhouchengming@bytedance.com References: <20230821073528.3469210-1-chengming.zhou@linux.dev> <20230821073528.3469210-3-chengming.zhou@linux.dev> From: Bart Van Assche In-Reply-To: <20230821073528.3469210-3-chengming.zhou@linux.dev> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 8/21/23 00:35, chengming.zhou@linux.dev wrote: > 2. __blk_mq_tagset_busy_iter() has BT_TAG_ITER_STARTED flag set, so only > started requests will be iterated, which should be more efficient. The above motivation sounds wrong to me. The goal here should be not to change the behavior of blk_mq_queue_tag_busy_iter(). Although blk_mq_queue_tag_busy_iter() iterates over more requests than only started requests, apparently blk_mq_queue_tag_busy_iter() is only used to iterate over started requests (blk_mq_request_started()). Please mention this in the patch description. Thanks, Bart.