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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT autolearn=ham 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 C6F19C282C4 for ; Tue, 22 Jan 2019 16:08:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9FD5620823 for ; Tue, 22 Jan 2019 16:08:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729212AbfAVQIC (ORCPT ); Tue, 22 Jan 2019 11:08:02 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:59895 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728580AbfAVQIC (ORCPT ); Tue, 22 Jan 2019 11:08:02 -0500 Received: from bigeasy by Galois.linutronix.de with local (Exim 4.80) (envelope-from ) id 1glyal-0000Lm-O2; Tue, 22 Jan 2019 17:07:59 +0100 Date: Tue, 22 Jan 2019 17:07:59 +0100 From: Sebastian Andrzej Siewior To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, Andrew Morton , Anders Roxell , Arnd Bergmann , Michal Hocko , linux-mm@kvack.org Subject: Re: [PATCH] backing-dev: no need to check return value of debugfs_create functions Message-ID: <20190122160759.mx3h7gjc23zmrvxc@linutronix.de> References: <20190122152151.16139-8-gregkh@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190122152151.16139-8-gregkh@linuxfoundation.org> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-01-22 16:21:07 [+0100], Greg Kroah-Hartman wrote: > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index 8a8bb8796c6c..85ef344a9c67 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -102,39 +102,25 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v) > } > DEFINE_SHOW_ATTRIBUTE(bdi_debug_stats); > > -static int bdi_debug_register(struct backing_dev_info *bdi, const char *name) > +static void bdi_debug_register(struct backing_dev_info *bdi, const char *name) > { > - if (!bdi_debug_root) > - return -ENOMEM; > - > bdi->debug_dir = debugfs_create_dir(name, bdi_debug_root); If this fails then ->debug_dir is NULL > - if (!bdi->debug_dir) > - return -ENOMEM; > - > - bdi->debug_stats = debugfs_create_file("stats", 0444, bdi->debug_dir, > - bdi, &bdi_debug_stats_fops); > - if (!bdi->debug_stats) { > - debugfs_remove(bdi->debug_dir); > - bdi->debug_dir = NULL; > - return -ENOMEM; > - } > > - return 0; > + debugfs_create_file("stats", 0444, bdi->debug_dir, bdi, > + &bdi_debug_stats_fops); then this creates the stats file in the root folder and > } > > static void bdi_debug_unregister(struct backing_dev_info *bdi) > { > - debugfs_remove(bdi->debug_stats); > - debugfs_remove(bdi->debug_dir); > + debugfs_remove_recursive(bdi->debug_dir); this won't remove it. If you return for "debug_dir == NULL" then it is a nice cleanup. Sebastian