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 50C6EC433EF for ; Tue, 8 Feb 2022 17:28:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 652946B0071; Tue, 8 Feb 2022 12:28:58 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 5DA096B0073; Tue, 8 Feb 2022 12:28:58 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 47AD76B0075; Tue, 8 Feb 2022 12:28:58 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0120.hostedemail.com [216.40.44.120]) by kanga.kvack.org (Postfix) with ESMTP id 324606B0071 for ; Tue, 8 Feb 2022 12:28:58 -0500 (EST) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id E69DF8249980 for ; Tue, 8 Feb 2022 17:28:57 +0000 (UTC) X-FDA: 79120297914.15.E608BBC Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by imf27.hostedemail.com (Postfix) with ESMTP id 3FFB840004 for ; Tue, 8 Feb 2022 17:28:57 +0000 (UTC) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id D175B210E1; Tue, 8 Feb 2022 17:28:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1644341335; h=from:from:reply-to: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=084qkkVKwxLtc8ghPiqPMfhm1DMYA6O/V2WaZEb6smo=; b=jqZ9+RlJpu2xYhBXfWYhPVl3HqCHQ+sLPeCxx54h2OdqdT9BuO2wBEqg3+EKf8vnkgkrv8 jIyrj47WXCn6zHDDWqHfRxMmnscqZEJ/tltl18hFq/wg/C/eXUHkr0z5605D2MYeUOHd58 IjhYrPIcLOuF28URKVmQ+XnOSJlNO00= Received: from suse.cz (unknown [10.100.201.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 999A9A3B85; Tue, 8 Feb 2022 17:28:55 +0000 (UTC) Date: Tue, 8 Feb 2022 18:28:54 +0100 From: Michal Hocko To: Sebastian Andrzej Siewior Cc: Vlastimil Babka , cgroups@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Johannes Weiner , Michal =?iso-8859-1?Q?Koutn=FD?= , Peter Zijlstra , Thomas Gleixner , Vladimir Davydov , Waiman Long Subject: Re: [PATCH 3/4] mm/memcg: Add a local_lock_t for IRQ and TASK object. Message-ID: References: <20220125164337.2071854-1-bigeasy@linutronix.de> <20220125164337.2071854-4-bigeasy@linutronix.de> <7f4928b8-16e2-88b3-2688-1519a19653a9@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 3FFB840004 X-Stat-Signature: nyruh8srb8pg1kuaum8nifwd8ksoxoxb X-Rspam-User: Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=suse.com header.s=susede1 header.b=jqZ9+RlJ; spf=pass (imf27.hostedemail.com: domain of mhocko@suse.com designates 195.135.220.28 as permitted sender) smtp.mailfrom=mhocko@suse.com; dmarc=pass (policy=quarantine) header.from=suse.com X-Rspamd-Server: rspam05 X-HE-Tag: 1644341337-770604 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 Tue 08-02-22 18:17:35, Sebastian Andrzej Siewior wrote: > On 2022-02-03 17:01:41 [+0100], Vlastimil Babka wrote: > > > Let me know if a revert is preferred or you want to keep that so that I > > > > I see that's discussed in the subthread with Michal Hocko, so I would be > > also leaning towards revert unless convincing numbers are provided. > > > > > can prepare the patches accordingly before posting. > > > > An acceptable form of this would have to basically replace the bool > > stock_lock_acquried with two variants of the code paths that rely on it, > > feel free to read though the previous occurence :) > > https://lore.kernel.org/all/CAHk-=wiJLqL2cUhJbvpyPQpkbVOu1rVSzgO2=S2jC55hneLtfQ@mail.gmail.com/ > > I did that locally already. I was referring to the revert. > So repost with bool fixed and the revert will be discussed later or > include the revert at the begin of the series and then rebase these > patches on top of it? I probably don't get to it before FRI so I don't > try to rush anyone here ;) If you start with the revert then you should be able to get rid of a lot of complexity, right? We still haven't heard from Weiman about his original optimization reasoning. There might be good reasons for it which just hasn't been explicitly mentioned yet. As already said, if the optimization is visible only in microbenchmarks without any real workload benefiting from it I would rather consider reverting it and make the RT addoption easier. Micro optimizations can always be done on top. -- Michal Hocko SUSE Labs