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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 0D70AC433E0 for ; Mon, 8 Feb 2021 10:49:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B166D64E76 for ; Mon, 8 Feb 2021 10:49:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229719AbhBHKtV (ORCPT ); Mon, 8 Feb 2021 05:49:21 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:12150 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232605AbhBHKqA (ORCPT ); Mon, 8 Feb 2021 05:46:00 -0500 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4DZ2gW6mNZz1658y; Mon, 8 Feb 2021 18:43:35 +0800 (CST) Received: from [127.0.0.1] (10.69.38.196) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.498.0; Mon, 8 Feb 2021 18:44:52 +0800 Subject: Re: [PATCH 1/4] driver core: Use subdir-ccflags-* to inherit debug flag To: Greg KH CC: , , , , , , , , , , , , , , , References: <1612518255-23052-1-git-send-email-yangyicong@hisilicon.com> <1612518255-23052-2-git-send-email-yangyicong@hisilicon.com> From: Yicong Yang Message-ID: <08017751-a1be-ea07-50de-73d14ab6d57e@hisilicon.com> Date: Mon, 8 Feb 2021 18:44:52 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.69.38.196] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Hi Greg, On 2021/2/5 17:53, Greg KH wrote: > On Fri, Feb 05, 2021 at 05:44:12PM +0800, Yicong Yang wrote: >> From: Junhao He >> >> Use subdir-ccflags-* instead of ccflags-* to inherit the debug >> settings from Kconfig when traversing subdirectories. > > That says what you do, but not _why_ you are doing it. i'll illustrate the reason and reword the commit. > > What does this offer in benefit of the existing way? What is it fixing? > Why do this "churn"? currently we have added ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG in the Makefile of driver/base and driver/base/power, but not in the subdirectory driver/base/firmware_loader. we cannot turn the debug on for subdirectory firmware_loader if we config DEBUG_DRIVER and there is no kconfig option for the it. as there is no other debug config in the subdirectory of driver/base, CONFIG_DEBUG_DRIVER may also mean turn on the debug in the subdirectories, so use subdir-ccflags-* instead for the -DDEBUG will allow us to enable debug for all the subdirectories. Thanks, Yicong > > thanks, > > greg k-h > > . >