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=-16.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, 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 B83F4C433E0 for ; Thu, 28 Jan 2021 17:46:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6391E64E15 for ; Thu, 28 Jan 2021 17:46:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232605AbhA1Rpz (ORCPT ); Thu, 28 Jan 2021 12:45:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:58968 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231549AbhA1Rpa (ORCPT ); Thu, 28 Jan 2021 12:45:30 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7F0CD64DEB; Thu, 28 Jan 2021 17:44:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1611855888; bh=C4CC3leKDF9w10IBWJGU6rv7NHMgT8fbQ7ox/gNpCbU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lQWEPVdWxfdP1cG3dynKgnic6jUk88V7lLcf1UI4dmrjHVzwGmF2tI2GV0yioOcVm 9ZZ2Zbl/zGB0xPfTabN7Tzom46rKsa6LQQlD6nRcMk7/ff+DkTnUY+ZFWKyM9aH9JI YVhgfa1slUurohWaZIQ1lrcpnwQM5i3enGprA7z5HBvIJym/viaqHO6uvcjtLKEly4 hbSOqbKfQS4vTqQSXASBFwMHvq38WVqn4dHBjVHRmj6lu3OQ9C8Q79oVtGcBnIYZPb TuXdFPho9a42qzzBjOI0lvPsink/9bEQMCDX5cmAAx6DEKIOfAOzngiuhTVUnFNooz BBZZPkOizWmOQ== Date: Thu, 28 Jan 2021 09:44:47 -0800 From: "Darrick J. Wong" To: Brian Foster Cc: Chandan Babu R , linux-xfs@vger.kernel.org, allison.henderson@oracle.com, kernel test robot Subject: Re: [PATCH] xfs: Fix 'set but not used' warning in xfs_bmap_compute_alignments() Message-ID: <20210128174447.GS7698@magnolia> References: <20210127090537.2640164-1-chandanrlinux@gmail.com> <20210128153412.GD2599027@bfoster> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210128153412.GD2599027@bfoster> Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Thu, Jan 28, 2021 at 10:34:12AM -0500, Brian Foster wrote: > On Wed, Jan 27, 2021 at 02:35:37PM +0530, Chandan Babu R wrote: > > With both CONFIG_XFS_DEBUG and CONFIG_XFS_WARN disabled, the only reference to > > local variable "error" in xfs_bmap_compute_alignments() gets eliminated during > > pre-processing stage of the compilation process. This causes the compiler to > > generate a "set but not used" warning. > > > > Reported-by: kernel test robot > > Signed-off-by: Chandan Babu R > > --- > > This patch is applicable on top of current xfs-linux/for-next branch. > > > > fs/xfs/libxfs/xfs_bmap.c | 9 ++++----- > > 1 file changed, 4 insertions(+), 5 deletions(-) > > > > diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c > > index 2cd24bb06040..ba56554e8c05 100644 > > --- a/fs/xfs/libxfs/xfs_bmap.c > > +++ b/fs/xfs/libxfs/xfs_bmap.c > > @@ -3471,7 +3471,6 @@ xfs_bmap_compute_alignments( > > struct xfs_mount *mp = args->mp; > > xfs_extlen_t align = 0; /* minimum allocation alignment */ > > int stripe_align = 0; > > - int error; > > > > /* stripe alignment for allocation is determined by mount parameters */ > > if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC)) > > @@ -3484,10 +3483,10 @@ xfs_bmap_compute_alignments( > > else if (ap->datatype & XFS_ALLOC_USERDATA) > > align = xfs_get_extsz_hint(ap->ip); > > if (align) { > > - error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, > > - align, 0, ap->eof, 0, ap->conv, > > - &ap->offset, &ap->length); > > - ASSERT(!error); > > + if (xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, > > + align, 0, ap->eof, 0, ap->conv, &ap->offset, > > + &ap->length)) > > + ASSERT(0); > > I was wondering if we should just make xfs_bmap_extsize_align() return > void and push the asserts down into the function itself, but it looks > like xfs_bmap_rtalloc() actually handles the error. Any idea on why we > might have that inconsistency? It only returns nonzero if isrt (the fifth parameter) is nonzero, and only if the requested range is still not aligned to the rt extent size after aligning it and eliminating any overlaps with existing extents. --D > Brian > > > ASSERT(ap->length); > > } > > > > -- > > 2.29.2 > > >