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=-6.5 required=3.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 0E806C32751 for ; Sat, 10 Aug 2019 19:27:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E2C2821880 for ; Sat, 10 Aug 2019 19:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726104AbfHJT1u (ORCPT ); Sat, 10 Aug 2019 15:27:50 -0400 Received: from smtp08.smtpout.orange.fr ([80.12.242.130]:18193 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726136AbfHJT1r (ORCPT ); Sat, 10 Aug 2019 15:27:47 -0400 Received: from belgarion ([90.76.53.202]) by mwinf5d31 with ME id nXTS2000D4MlyVm03XTeb7; Sat, 10 Aug 2019 21:27:43 +0200 X-ME-Helo: belgarion X-ME-Auth: amFyem1pay5yb2JlcnRAb3JhbmdlLmZy X-ME-Date: Sat, 10 Aug 2019 21:27:43 +0200 X-ME-IP: 90.76.53.202 From: Robert Jarzmik To: Greg Kroah-Hartman Cc: dan.j.williams@intel.com, vkoul@kernel.org, Daniel Mack , Haojian Zhuang , linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/6] dma: pxa_dma: no need to check return value of debugfs_create functions References: <20190612122557.24158-1-gregkh@linuxfoundation.org> <20190612122557.24158-4-gregkh@linuxfoundation.org> X-URL: http://belgarath.falguerolles.org/ Date: Sat, 10 Aug 2019 21:27:26 +0200 In-Reply-To: <20190612122557.24158-4-gregkh@linuxfoundation.org> (Greg Kroah-Hartman's message of "Wed, 12 Jun 2019 14:25:55 +0200") Message-ID: <87tvaorfc1.fsf@belgarion.home> User-Agent: Gnus/5.130008 (Ma Gnus v0.8) Emacs/26 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Greg Kroah-Hartman writes: Hi Greg, > When calling debugfs functions, there is no need to ever check the > return value. The function can work or not, but the code logic should > never do something different based on this. > > Also, because there is no need to save the file dentry, remove the > variable that was saving it as it was never even being used once set. > > Cc: Daniel Mack > Cc: Haojian Zhuang > Cc: Robert Jarzmik > Cc: Vinod Koul > Cc: Dan Williams > Cc: linux-arm-kernel@lists.infradead.org > Cc: dmaengine@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Greg Kroah-Hartman > --- > drivers/dma/pxa_dma.c | 56 +++++++++---------------------------------- > 1 file changed, 11 insertions(+), 45 deletions(-) > > diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c > index b429642f3e7a..0f698f49ee26 100644 > --- a/drivers/dma/pxa_dma.c > +++ b/drivers/dma/pxa_dma.c > @@ -132,7 +132,6 @@ struct pxad_device { > spinlock_t phy_lock; /* Phy association */ > #ifdef CONFIG_DEBUG_FS > struct dentry *dbgfs_root; > - struct dentry *dbgfs_state; > struct dentry **dbgfs_chan; > #endif > }; > @@ -326,31 +325,18 @@ static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev, > int ch, struct dentry *chandir) > { > char chan_name[11]; > - struct dentry *chan, *chan_state = NULL, *chan_descr = NULL; > - struct dentry *chan_reqs = NULL; > + struct dentry *chan; > void *dt; > > scnprintf(chan_name, sizeof(chan_name), "%d", ch); > chan = debugfs_create_dir(chan_name, chandir); > dt = (void *)&pdev->phys[ch]; > > - if (chan) > - chan_state = debugfs_create_file("state", 0400, chan, dt, > - &chan_state_fops); > - if (chan_state) > - chan_descr = debugfs_create_file("descriptors", 0400, chan, dt, > - &descriptors_fops); > - if (chan_descr) > - chan_reqs = debugfs_create_file("requesters", 0400, chan, dt, > - &requester_chan_fops); > - if (!chan_reqs) > - goto err_state; > + debugfs_create_file("state", 0400, chan, dt, &chan_state_fops); > + debugfs_create_file("descriptors", 0400, chan, dt, &descriptors_fops); > + debugfs_create_file("requesters", 0400, chan, dt, &requester_chan_fops); This is not strictly equivalent. Imagine that the debugfs_create_dir() fails and returns NULL : - in the former case, neither "state", "descriptors" nor "requesters" would be created - in the new code, "state", "descriptors" nor "requesters" will be created in the debugfs root directory Apart from that it looks fine. Cheers. -- Robert