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 E2167C77B73 for ; Tue, 2 May 2023 02:22:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232184AbjEBCWi (ORCPT ); Mon, 1 May 2023 22:22:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48514 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233181AbjEBCWf (ORCPT ); Mon, 1 May 2023 22:22:35 -0400 Received: from bedivere.hansenpartnership.com (bedivere.hansenpartnership.com [IPv6:2607:fcd0:100:8a00::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E931C40C5; Mon, 1 May 2023 19:22:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1682994147; bh=XleaLi6oRjXtfe2D7RhL/bXb9kAyYfGf1xyiXtDlQDk=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References:From; b=B3+pvvNt1nRN8hRoSXjf3I4ybVi/EDboNnvLeMqv3k3o/5KuewFLsQ2LIIO45T87D dmw9Bza7VZEKEtygO+CQeSy7CBK508rzVVZKe8uhSLnG5n4AwGQmHHjTyQBjyKut87 W4mECobpPwTueeG1X8Y0LfbxM9hzHFolb5i0L6ew= Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 554B4128648F; Mon, 1 May 2023 22:22:27 -0400 (EDT) Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavis, port 10024) with ESMTP id XSNGV24ZawPq; Mon, 1 May 2023 22:22:27 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1682994146; bh=XleaLi6oRjXtfe2D7RhL/bXb9kAyYfGf1xyiXtDlQDk=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References:From; b=m6bYz5hNQXdxoZ5NOAcJ2JFL0kL9SDAdXRGd+EFNCj+3OnfQ3+swh//Kmg4+1ZxnT /vAaVHfPpqrg0q8i1pJguyqq2gnSLJOdqlrDbhqXY73Dx/2yBSTryYz6FylsmhHOQk kWyP5cXIJTuLLvuvIQl6DHYlZBed/Vghiiim+rwE= Received: from lingrow.int.hansenpartnership.com (unknown [IPv6:2601:5c4:4302:c21::c14]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id 25B2E1285C64; Mon, 1 May 2023 22:22:21 -0400 (EDT) Message-ID: Subject: Re: [PATCH 01/40] lib/string_helpers: Drop space in string_get_size's output From: James Bottomley To: Kent Overstreet , Suren Baghdasaryan , akpm@linux-foundation.org, mhocko@suse.com, vbabka@suse.cz, hannes@cmpxchg.org, roman.gushchin@linux.dev, mgorman@suse.de, willy@infradead.org, liam.howlett@oracle.com, corbet@lwn.net, void@manifault.com, peterz@infradead.org, juri.lelli@redhat.com, ldufour@linux.ibm.com, catalin.marinas@arm.com, will@kernel.org, arnd@arndb.de, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org, peterx@redhat.com, david@redhat.com, axboe@kernel.dk, mcgrof@kernel.org, masahiroy@kernel.org, nathan@kernel.org, dennis@kernel.org, tj@kernel.org, muchun.song@linux.dev, rppt@kernel.org, paulmck@kernel.org, pasha.tatashin@soleen.com, yosryahmed@google.com, yuzhao@google.com, dhowells@redhat.com, hughd@google.com, andreyknvl@gmail.com, keescook@chromium.org, ndesaulniers@google.com, gregkh@linuxfoundation.org, ebiggers@google.com, ytcoode@gmail.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, bristot@redhat.com, vschneid@redhat.com, cl@linux.com, penberg@kernel.org, iamjoonsoo.kim@lge.com, 42.hyeyoo@gmail.com, glider@google.com, elver@google.com, dvyukov@google.com, shakeelb@google.com, songmuchun@bytedance.com, jbaron@akamai.com, rientjes@google.com, minchan@google.com, kaleshsingh@google.com, kernel-team@android.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, kasan-dev@googlegroups.com, cgroups@vger.kernel.org, Andy Shevchenko , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , "Michael S. Tsirkin" , Jason Wang , Noralf =?ISO-8859-1?Q?Tr=EF=BF=BDnnes?= Date: Mon, 01 May 2023 22:22:18 -0400 In-Reply-To: References: <20230501165450.15352-1-surenb@google.com> <20230501165450.15352-2-surenb@google.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.4 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On Mon, 2023-05-01 at 15:35 -0400, Kent Overstreet wrote: > On Mon, May 01, 2023 at 11:13:15AM -0700, Davidlohr Bueso wrote: > > On Mon, 01 May 2023, Suren Baghdasaryan wrote: > > > > > From: Kent Overstreet > > > > > > Previously, string_get_size() outputted a space between the > > > number and the units, i.e. > > >  9.88 MiB > > > > > > This changes it to > > >  9.88MiB > > > > > > which allows it to be parsed correctly by the 'sort -h' command. > > > > Wouldn't this break users that already parse it the current way? > > It's not impossible - but it's not used in very many places and we > wouldn't be printing in human-readable units if it was meant to be > parsed - it's mainly used for debug output currently. It is not used just for debug. It's used all over the kernel for printing out device sizes. The output mostly goes to the kernel print buffer, so it's anyone's guess as to what, if any, tools are parsing it, but the concern about breaking log parsers seems to be a valid one. > If someone raises a specific objection we'll do something different, > otherwise I think standardizing on what userspace tooling already > parses is a good idea. If you want to omit the space, why not simply add your own variant? A string_get_size_nospace() which would use most of the body of this one as a helper function but give its own snprintf format string at the end. It's only a couple of lines longer as a patch and has the bonus that it definitely wouldn't break anything by altering an existing output. James