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 2727AECAAD3 for ; Fri, 9 Sep 2022 22:44:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229953AbiIIWom (ORCPT ); Fri, 9 Sep 2022 18:44:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229552AbiIIWoj (ORCPT ); Fri, 9 Sep 2022 18:44:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0531F24F2A for ; Fri, 9 Sep 2022 15:44:36 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DFFDA620F0 for ; Fri, 9 Sep 2022 22:44:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C6D7C433D6; Fri, 9 Sep 2022 22:44:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1662763475; bh=UR0/qf49iaA12b1h+bJxCdBOdwx4P6K5iqMbkzq4aAo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=CgMdko5lp0xtwBaPIPLFkXtOwAwHW3tXXLlSzH+1jK8Uo+Z99m1SK/hXHTlp8Bm/0 rzumAzbJOea2z/sGyB0FSo9S2631CccZ/jLswx/KKvIEshtVk+YuYyXRgum2n+olPK T3QxNI7Zb4mwpyuxi/Xd4sJNY68cHvHj67uHMdk4= Date: Fri, 9 Sep 2022 15:44:34 -0700 From: Andrew Morton To: SeongJae Park Cc: Xin Hao , damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/damon/sysfs: change few functions execute order Message-Id: <20220909154434.5870e33657a11d53320861e7@linux-foundation.org> In-Reply-To: <20220908221653.131120-1-sj@kernel.org> References: <20220908151042.239189ddb1635c0f598c6fd2@linux-foundation.org> <20220908221653.131120-1-sj@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 8 Sep 2022 22:16:53 +0000 SeongJae Park wrote: > Reviewed-by: SeongJae Park Cool. I rewrote the changelog significantly: From: Xin Hao Subject: mm/damon/sysfs: change few functions execute order Date: Thu, 8 Sep 2022 16:19:32 +0800 There's no need to run container_of() as early as we do. The compiler figures this out, but the resulting code is more readable. Link: https://lkml.kernel.org/r/20220908081932.77370-1-xhao@linux.alibaba.com Signed-off-by: Xin Hao Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton --- mm/damon/sysfs.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) --- a/mm/damon/sysfs.c~mm-damon-sysfs-change-few-functions-execute-order +++ a/mm/damon/sysfs.c @@ -1031,8 +1031,7 @@ static ssize_t nr_schemes_show(struct ko static ssize_t nr_schemes_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - struct damon_sysfs_schemes *schemes = container_of(kobj, - struct damon_sysfs_schemes, kobj); + struct damon_sysfs_schemes *schemes; int nr, err = kstrtoint(buf, 0, &nr); if (err) @@ -1040,6 +1039,8 @@ static ssize_t nr_schemes_store(struct k if (nr < 0) return -EINVAL; + schemes = container_of(kobj, struct damon_sysfs_schemes, kobj); + if (!mutex_trylock(&damon_sysfs_lock)) return -EBUSY; err = damon_sysfs_schemes_add_dirs(schemes, nr); @@ -1237,8 +1238,7 @@ static ssize_t nr_regions_show(struct ko static ssize_t nr_regions_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - struct damon_sysfs_regions *regions = container_of(kobj, - struct damon_sysfs_regions, kobj); + struct damon_sysfs_regions *regions; int nr, err = kstrtoint(buf, 0, &nr); if (err) @@ -1246,6 +1246,8 @@ static ssize_t nr_regions_store(struct k if (nr < 0) return -EINVAL; + regions = container_of(kobj, struct damon_sysfs_regions, kobj); + if (!mutex_trylock(&damon_sysfs_lock)) return -EBUSY; err = damon_sysfs_regions_add_dirs(regions, nr); @@ -1440,8 +1442,7 @@ static ssize_t nr_targets_show(struct ko static ssize_t nr_targets_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - struct damon_sysfs_targets *targets = container_of(kobj, - struct damon_sysfs_targets, kobj); + struct damon_sysfs_targets *targets; int nr, err = kstrtoint(buf, 0, &nr); if (err) @@ -1449,6 +1450,8 @@ static ssize_t nr_targets_store(struct k if (nr < 0) return -EINVAL; + targets = container_of(kobj, struct damon_sysfs_targets, kobj); + if (!mutex_trylock(&damon_sysfs_lock)) return -EBUSY; err = damon_sysfs_targets_add_dirs(targets, nr); @@ -1962,8 +1965,7 @@ static ssize_t nr_contexts_show(struct k static ssize_t nr_contexts_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - struct damon_sysfs_contexts *contexts = container_of(kobj, - struct damon_sysfs_contexts, kobj); + struct damon_sysfs_contexts *contexts; int nr, err; err = kstrtoint(buf, 0, &nr); @@ -1973,6 +1975,7 @@ static ssize_t nr_contexts_store(struct if (nr < 0 || 1 < nr) return -EINVAL; + contexts = container_of(kobj, struct damon_sysfs_contexts, kobj); if (!mutex_trylock(&damon_sysfs_lock)) return -EBUSY; err = damon_sysfs_contexts_add_dirs(contexts, nr); @@ -2737,8 +2740,7 @@ static ssize_t nr_kdamonds_show(struct k static ssize_t nr_kdamonds_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - struct damon_sysfs_kdamonds *kdamonds = container_of(kobj, - struct damon_sysfs_kdamonds, kobj); + struct damon_sysfs_kdamonds *kdamonds; int nr, err; err = kstrtoint(buf, 0, &nr); @@ -2747,6 +2749,8 @@ static ssize_t nr_kdamonds_store(struct if (nr < 0) return -EINVAL; + kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj); + if (!mutex_trylock(&damon_sysfs_lock)) return -EBUSY; err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr); _