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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 CE7BBC433DB for ; Fri, 26 Mar 2021 11:20:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 988D561A38 for ; Fri, 26 Mar 2021 11:20:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229794AbhCZLTd (ORCPT ); Fri, 26 Mar 2021 07:19:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229463AbhCZLTE (ORCPT ); Fri, 26 Mar 2021 07:19:04 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26B66C0613AA for ; Fri, 26 Mar 2021 04:19:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=nbfdoB56OSJA++wkCwG7Y5R4eFfXpQtmTwFSIJHLz/c=; b=G8FismzwdvL19CPX/qdZjbZHtY E/9TiTrhEgksF9ea/z3GayckiadJIzULXnkoHdCgpCO+qh2eGH6+1ToX461+RF14w7xEjGs6FRqmF P/wTRoR+wqLYkjL4sEKUbcjPqXuFJsmsP4sjI5QgqpO2PV9dly8mpGKdOAUBhwHvOa7kDMKqsDVR5 wjl873BjVs/Ti8DUf2QyjayHybZvq+/gtlN+RRGw261ZwusU2EH/z81zkMUcCBS8eSfzxjlsYFqNj caTxbZ3ZZ3lwYedsk47yyZvMEI/MaA0NzT5SA2GIDxvnVT4LFfzOJrXmFfk5VojNyOliReKIgnq4t LiTAQgmQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lPkUK-003QTl-15; Fri, 26 Mar 2021 11:18:48 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id A95343003E1; Fri, 26 Mar 2021 12:18:47 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7020A2BCA7ED2; Fri, 26 Mar 2021 12:18:47 +0100 (CET) Date: Fri, 26 Mar 2021 12:18:47 +0100 From: Peter Zijlstra To: Greg KH Cc: mingo@kernel.org, mgorman@suse.de, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, bristot@redhat.com, joshdon@google.com, valentin.schneider@arm.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 6/9] debugfs: Implement debugfs_create_str() Message-ID: References: <20210326103352.603456266@infradead.org> <20210326103935.183934395@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 26, 2021 at 12:05:07PM +0100, Greg KH wrote: > On Fri, Mar 26, 2021 at 11:33:58AM +0100, Peter Zijlstra wrote: > > > > Signed-off-by: Peter Zijlstra (Intel) > > No changelog text? :( Yeah, didn't really know what to say that the Subject didn't already do. > > +/** > > + * debugfs_create_str - create a debugfs file that is used to read and write a string value > > + * @name: a pointer to a string containing the name of the file to create. > > + * @mode: the permission that the file should have > > + * @parent: a pointer to the parent dentry for this file. This should be a > > + * directory dentry if set. If this parameter is %NULL, then the > > + * file will be created in the root of the debugfs filesystem. > > + * @value: a pointer to the variable that the file should read to and write > > + * from. > > + * > > + * This function creates a file in debugfs with the given name that > > + * contains the value of the variable @value. If the @mode variable is so > > + * set, it can be read from, and written to. > > + * > > + * This function will return a pointer to a dentry if it succeeds. This > > + * pointer must be passed to the debugfs_remove() function when the file is > > + * to be removed (no automatic cleanup happens if your module is unloaded, > > + * you are responsible here.) If an error occurs, ERR_PTR(-ERROR) will be > > + * returned. > > + * > > + * NOTE: when writing is enabled it will replace the string, string lifetime is > > + * assumed to be RCU managed. > > + * > > + * If debugfs is not enabled in the kernel, the value ERR_PTR(-ENODEV) will > > + * be returned. > > + */ > > +struct dentry *debugfs_create_str(const char *name, umode_t mode, > > + struct dentry *parent, char **value) > > Please have this return void, no need for me to have to clean up > afterward later on :) That would make it inconsistent with debugfs_create_{bool,blob}() from which I copiously 'borrowed'. Also, the return dentry might be useful with debugfs_create_symlink(), but you're right in that most other create_file wrappers return void.