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x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1659744475; a=rsa-sha256; cv=none; b=hAdrGhurVtDMKkSwIDIXE/suo6xDuDubWgwPZB6cLKe4rhNFmUZSiYs+MmCYSL2cq7oH/1 L1kGy6Ie/snmAH2IcTKsfSqyxH8WBd2OanTfphf8l02oNG7NJ3K1uRXK9Wzs/+JHYtWuKc l4YWb+Sga9UKMyvegzVaP0yIbKw5i5k= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=lC4Fldht; spf=pass (imf05.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1659744475; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=851HsS8zvCWEJiYPBSxTEdaKXW7uFcYviu0bAAAPiQM=; b=paA1P3dXBkvaV+OuD5GVYosINHrO0ed5qOXDfvjam1fHHeVvh8gO1bfaRYgw5R8VIA1MD6 XfyZROaRVRsspSdbZUL4n9tfdDPuYcNhzz+NHqwYZvKCx2S/llrywrqeSxVqMGjomvlqO1 zhK5kWgr48Q9owuh4Ae62IaEg9k+KVE= X-Stat-Signature: 3ysyk89951aaqjj37ajj5xsp76d1soju X-Rspamd-Queue-Id: 6DA2310013A Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=lC4Fldht; spf=pass (imf05.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam05 X-HE-Tag: 1659744474-48332 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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.