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 ADAC0C00140 for ; Sat, 6 Aug 2022 01:43:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241563AbiHFBnj convert rfc822-to-8bit (ORCPT ); Fri, 5 Aug 2022 21:43:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237456AbiHFBni (ORCPT ); Fri, 5 Aug 2022 21:43:38 -0400 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E3CA11471 for ; Fri, 5 Aug 2022 18:43:36 -0700 (PDT) Received: from omf13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 8EF7A406F2; Sat, 6 Aug 2022 01:43:34 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: joe@perches.com) by omf13.hostedemail.com (Postfix) with ESMTPA id C544920010; Sat, 6 Aug 2022 01:43:32 +0000 (UTC) Message-ID: <12695fa86c0e3e062077b5e11a66234d9404e4a2.camel@perches.com> Subject: Re: [GIT PULL] MM updates for 5.20-rc1 From: Joe Perches To: Andrew Morton , Roman Gushchin Cc: Linus Torvalds , Kent Overstreet , mm-commits@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dave Chinner Date: Fri, 05 Aug 2022 18:43:32 -0700 In-Reply-To: <20220805170752.d609551360017d60903e5e75@linux-foundation.org> References: <20220803133541.18b82ec9344ed0e8b975fe5b@linux-foundation.org> <20220805170752.d609551360017d60903e5e75@linux-foundation.org> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 8BIT User-Agent: Evolution 3.44.1-0ubuntu1 MIME-Version: 1.0 X-Stat-Signature: qyrp8argzkghi98fkgmfsdzcootm5dgb X-Rspamd-Server: rspamout08 X-Rspamd-Queue-Id: C544920010 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Session-ID: U2FsdGVkX1/PQT5mEc4qSatyOMKaUxBPL8ydPsKALW0= X-HE-Tag: 1659750212-509346 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2022-08-05 at 17:07 -0700, Andrew Morton wrote: > On Fri, 5 Aug 2022 17:04:28 -0700 Roman Gushchin wrote: > > > On Fri, Aug 05, 2022 at 04:32:34PM -0700, Linus Torvalds wrote: > > > On Wed, Aug 3, 2022 at 1:35 PM Andrew Morton wrote: > > > > > > > > - memcg debug/visibility work from Roman Gushchin > > > > > > Well, not just memcg. > > > > > > There's that new CONFIG_SHRINKER_DEBUG too. > > > > > > Which looks like yet another "people add Kconfig options incorrectly". > > > > > > We don't make new features "default y" unless there's some truly > > > pressing reason for it (ie "99.9% of all people will want this" or "we > > > used to always compile this in, now it's optional"). > > > > Hi Linus! > > > > It actually was 'default n' in one of the earlier version of the patchset > > and has been switched to 'default y' based on the following feedback from > > Dave Chinner (https://lore.kernel.org/lkml/YmiWK56bOHyrr64u@rh/): > > > > No. The argument that "if we turn it off there's no overhead" means > > one of two things: > > > > 1. nobody turns it on and it never gets tested and so bitrots and is > > useless, or > > 2. distro's all turn it on because some tool they ship or customer > > they ship to wants it. > > > > Either way, hiding it behind a config option is not an acceptible > > solution for mering poorly thought out infrastructure. > > > > Personally I think that the feature is not that useful for the majority > > of users (this is why default was n), but it's not adding much of the > > overhead, so I had no strong reasons to oppose Dave. > > Cc'ing him just in case. > > > > We should have changelogged these considerations. > > I've asked Joe if checkpatch can get a "default y" detector, to draw > attention to this in the future. Perhaps: --- scripts/checkpatch.pl | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index bf7c5abeefaad..1abec0cd217e6 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3523,6 +3523,19 @@ sub process { } } +# check new Kconfig entries for default=y +# Only applies when adding the entry originally and if the entry is not +# conditional on anything like default y if + if ($realfile =~ /Kconfig/ && + !$file && + $line =~ /\+\s*default\s+y\s*$/i) { + if (WARN("KCONFIG_DEFAULT_Y", + "Kconfig entries should generally not be default y\n" . $herecurr) && + $fix) { + $fixed[$fixlinenr] =~ s/default(\s+)y/default${1}n/; + } + } + # check MAINTAINERS entries if ($realfile =~ /^MAINTAINERS$/) { # check MAINTAINERS entries for the right form