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=-5.3 required=3.0 tests=BAYES_00, 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 8E2F4C5519F for ; Sat, 14 Nov 2020 20:57:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E63F2242C for ; Sat, 14 Nov 2020 20:57:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726433AbgKNU50 (ORCPT ); Sat, 14 Nov 2020 15:57:26 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:43723 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726177AbgKNU50 (ORCPT ); Sat, 14 Nov 2020 15:57:26 -0500 Received: by mail-pl1-f194.google.com with SMTP id u2so6193499pls.10; Sat, 14 Nov 2020 12:57:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=16xSpaXhAEOF0N0U9OOB7ZCXwUuMywa2m2HceEa9Iw4=; b=tU9OtLBUbtIpY0BAlF9ddBuoAKPE72vMrtV7BHSzoV1E82gfqbtiF8zeX2yVvy9ZVU YvS37Im0ley4KITvrhyvGqlmWtTBjLax2xwoB0/vuxuyrVB8SwEHdvPXL2WOcWFYyx/e bDl6OoZ6oseH+gvkyRTEDuVATC09CLNAO1Mf29Ew5I/jMKWQQ8lN8jr/IkolRKR8jk1U LKBNCdo5yvTYhEQYVP/B9yx3xz+Tk/ACHD26Z8MGqYrCH8Zv/UmY9kUkYtcz4hW54Dar moNIYYXnlzoq5x4PV6wnAYwkH3BPYcsUYJberJz0C3PyDUvX9kDFWpip7cubj9hN1JHb QfqA== X-Gm-Message-State: AOAM531AXOidRLFqdTPIhvFOlO2+PNGiPbVN0DWNrAi3nHzIrYrc5uJl 7ftFIM5q01ljzrka+4XX1m0= X-Google-Smtp-Source: ABdhPJxN95asfd2nvQMo510YjA+Wku+VpWqlMQg1JxXwovicCEenAsosTW2ocPXCqEjyuH7KN1z7vA== X-Received: by 2002:a17:90a:7409:: with SMTP id a9mr9219187pjg.48.1605387445013; Sat, 14 Nov 2020 12:57:25 -0800 (PST) Received: from [192.168.3.218] (c-73-241-217-19.hsd1.ca.comcast.net. [73.241.217.19]) by smtp.gmail.com with ESMTPSA id g1sm14268854pjt.40.2020.11.14.12.57.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 14 Nov 2020 12:57:23 -0800 (PST) Subject: Re: [PATCH RFC v1 1/1] scsi: pm: Leave runtime resume along if block layer PM is enabled To: Can Guo , asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, ziqichen@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com Cc: Stanley Chu , "James E.J. Bottomley" , "Martin K. Petersen" , Matthias Brugger , open list , "moderated list:ARM/Mediatek SoC support" , "moderated list:ARM/Mediatek SoC support" References: <1605249009-13752-1-git-send-email-cang@codeaurora.org> <1605249009-13752-2-git-send-email-cang@codeaurora.org> From: Bart Van Assche Message-ID: <97dea590-5f2e-b4e3-ac64-7c346761c523@acm.org> Date: Sat, 14 Nov 2020 12:57:21 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <1605249009-13752-2-git-send-email-cang@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/12/20 10:30 PM, Can Guo wrote: > If block layer runtime PM is enabled for one SCSI device, then there is > no need to forcibly change the SCSI device and its request queue's runtime > PM status to active in scsi_dev_type_resume(), since block layer PM shall > resume the SCSI device on the demand of bios. Please change "along" into "alone" in the subject of this patch (if that is what you meant). > + if (scsi_is_sdev_device(dev)) { > + struct scsi_device *sdev; > > + sdev = to_scsi_device(dev); A minor comment: I think that "struct scsi_device *sdev = to_scsi_device(dev);" fits on a single line. > + * If block layer runtime PM is enabled for the SCSI device, > + * let block layer PM handle its runtime PM routines. Please change "its runtime PM routines" into "runtime resume" or similar. I think that will make the comment more clear. > + if (sdev->request_queue->dev) > + return err; > + } The 'dev' member only exists in struct request_queue if CONFIG_PM=y so the above won't compile if CONFIG_PM=n. How about adding a function in include/linux/blk-pm.h to check whether or not runtime PM has been enabled? Otherwise this patch looks good to me. Thanks, Bart.