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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5BF4C4167B for ; Sat, 9 Dec 2023 02:04:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5CE846B0089; Fri, 8 Dec 2023 21:04:34 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 57F0D6B008A; Fri, 8 Dec 2023 21:04:34 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 44F7A6B008C; Fri, 8 Dec 2023 21:04:34 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 31D1F6B008A for ; Fri, 8 Dec 2023 21:04:34 -0500 (EST) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 09A0D403F6 for ; Sat, 9 Dec 2023 02:04:34 +0000 (UTC) X-FDA: 81545635668.26.2A9C88A Received: from out-176.mta1.migadu.com (out-176.mta1.migadu.com [95.215.58.176]) by imf23.hostedemail.com (Postfix) with ESMTP id 27E57140013 for ; Sat, 9 Dec 2023 02:04:31 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=Wxoo0yrt; spf=pass (imf23.hostedemail.com: domain of kent.overstreet@linux.dev designates 95.215.58.176 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1702087472; a=rsa-sha256; cv=none; b=03sc5y8weLNRpDfDJGFRUroGLjXwM/0gD14F99p9bT/P6OTeryiKZgv3Fz3cnvTcCpOFKn qVelMpRmrSZH0dkpBngksJx8N/CDoGCNtgrvRHB2fxQXXcxhxDLJO476elZcmQCw7Ab+jW D+pMfkW4fTNldDoo5Nq/9Z1RMM03+8k= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=Wxoo0yrt; spf=pass (imf23.hostedemail.com: domain of kent.overstreet@linux.dev designates 95.215.58.176 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1702087472; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=91VJ/1+lLpk39C0D6ifXxcy869tSZFI3pQXERYTVjWw=; b=Zqx89RysSI4SNRAtBWhF8R1EZyeYVyJ4hSdNs3Iv9Z0Q00B+wpUJpY5p2RsL+VNmLgj5d1 8TVDF5HF1ZkIEX32qmOfU8PCSX43HTy2q201wJ8SpNkL8/z0pGlPMK1CpMU7uH+GTmZwHr waqJyFSnrmT0ziJZqtofulfKEzyi6zU= Date: Fri, 8 Dec 2023 21:04:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1702087470; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=91VJ/1+lLpk39C0D6ifXxcy869tSZFI3pQXERYTVjWw=; b=Wxoo0yrt6OLNSnz1f5bqGCzGTe5j8p0NYBZp99+RUQiRA1vbJEr4McfiJcDH3THPEg6MWf ZDWWhGEO0QZXO2v/3ofHw9eSf18pUCuTOLkKVrnBCaTYbz2zonFcB7lsVKcRYM6M7mGTad CtWMLSJto21OUY3XJSteHErWdM0k/jQ= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Kent Overstreet To: Roman Gushchin Cc: Dave Chinner , Qi Zheng , Michal Hocko , Muchun Song , Linux-MM , linux-kernel@vger.kernel.org, Andrew Morton Subject: Re: [PATCH 2/7] mm: shrinker: Add a .to_text() method for shrinkers Message-ID: <20231209020426.kqnib3xgtmfurskc@moria.home.lan> References: <20231129231147.7msiocerq7phxnyu@moria.home.lan> <04f63966-af72-43ef-a65c-ff927064a3e4@bytedance.com> <20231130032149.ynap4ai47dj62fy3@moria.home.lan> <20231206191349.x52nm3ercxelh3dx@moria.home.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 27E57140013 X-Stat-Signature: yc8553hpe36dx3k85zyp3d56smwsw3r8 X-Rspam-User: X-HE-Tag: 1702087471-631439 X-HE-Meta: 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 YnwSAKsC 0q2ot5irpgN93Kb3cdycj8yPgR3oz+HGY6xt0PfRPK1KuRaDAGFXcxk/uiIPa2S4SPGo8ajHJ5NzjPAswuCD6I9mlCQNUFjbHzBhW 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: List-Subscribe: List-Unsubscribe: On Fri, Dec 08, 2023 at 05:44:16PM -0800, Roman Gushchin wrote: > On Wed, Dec 06, 2023 at 02:13:49PM -0500, Kent Overstreet wrote: > 0;95;0c> On Wed, Dec 06, 2023 at 07:16:04PM +1100, Dave Chinner wrote: > > > On Fri, Dec 01, 2023 at 12:01:33PM -0800, Roman Gushchin wrote: > > > > What would be the proper solution to this problem from your point of view? > > > > What functionality/API mm can provide to make the life of fs developers > > > > better here? > > > > > > What can we do better? > > > > > > The first thing we can do better that comes to mind is to merge > > > Kent's patches that allow the shrinker owner to output debug > > > information when requested by the infrastructure. > > > > > > Then we - the shrinker implementers - have some control of our own > > > destiny. We can add whatever we need to solve shrinker and OOM > > > problems realted to our shrinkers not doing the right thing. > > > > > > But without that callout from the infrastructure and the > > > infrastructure to drive it at appropriate times, we will make zero > > > progress improving the situation. > > > > > > Yes, the code may not be perfect and, yes, it may not be useful to > > > mm developers, but for the people who have to debug shrinker related > > > problems in production systems we need all the help we can get. We > > > certainly don't care if it isn't perfect, just having something we > > > can partially tailor to our iindividual needs is far, far better > > > than the current situation of nothing at all... > > > > Of course if mm people don't want it I've got better things to do than > > fight uphill battles just to get some reviewed-by tags. Real high > > quality review feedback in this thread. > > (ignoring an attack towards all mm people, sigh) > > Kent, I think extending the shrinker debugfs interface is useful. > And in this context there is no need to limit the output to 10 items. > Also most of disagreements will vanish (sorry, if I missed something, > but looks like all concerns are related to the oom part). > Will it work for you? > > If yes, would you be able to drop the oom part (at least for now) > and resend the patchset? No: OOM debugging is the entire point of the patchset.