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 AA024C4167B for ; Wed, 29 Nov 2023 17:00:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 394BB6B03DD; Wed, 29 Nov 2023 12:00:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 343BB6B03DE; Wed, 29 Nov 2023 12:00:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 20CA06B03DF; Wed, 29 Nov 2023 12:00:06 -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 0F0AB6B03DD for ; Wed, 29 Nov 2023 12:00:06 -0500 (EST) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id DCBC116059E for ; Wed, 29 Nov 2023 17:00:05 +0000 (UTC) X-FDA: 81511604370.07.4EF5F7A Received: from mail-qk1-f178.google.com (mail-qk1-f178.google.com [209.85.222.178]) by imf21.hostedemail.com (Postfix) with ESMTP id 994B61C000E for ; Wed, 29 Nov 2023 17:00:03 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=cmpxchg-org.20230601.gappssmtp.com header.s=20230601 header.b=1RQ791Tp; spf=pass (imf21.hostedemail.com: domain of hannes@cmpxchg.org designates 209.85.222.178 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (policy=none) header.from=cmpxchg.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1701277203; a=rsa-sha256; cv=none; b=TUvLzE+lD9XOqtDgw/8gzfgC0Uo1pHQK25+usjPIuSrz59pd8gopPNhBwcUT4eabdKd+BP IN6iShObJmhOg1dfKtxBlw+FzmTbBtqoSJnX9n8PEWeCjW2/9Njs5Hi8eQbzT25lNmIQf7 GtJxGEPWFgJdO3EEbgIR67ShLJDc+ec= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=cmpxchg-org.20230601.gappssmtp.com header.s=20230601 header.b=1RQ791Tp; spf=pass (imf21.hostedemail.com: domain of hannes@cmpxchg.org designates 209.85.222.178 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (policy=none) header.from=cmpxchg.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1701277203; 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=U8mgkS00IbNP5jyZ+NO8ODgKFBs6g0ytgBOeKMTZ8ns=; b=S9xaUIatLS9R8A2ilwiGWGkQMlvg4pOIYhftXj/xDfF3wD0hbwXkIbRGxUP1AwZdFNz3Cc gIxrbQ8nQmFADPc9WkOWTVUO8YitC7d3tRz9AKQU22fInAMiJ/DIRxFzH/oT9cwS2nOGQB zEDp3ZHuGCj4GD+xEYfP7yuZSs2IlJ0= Received: by mail-qk1-f178.google.com with SMTP id af79cd13be357-77d8c38ea78so237247085a.0 for ; Wed, 29 Nov 2023 09:00:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20230601.gappssmtp.com; s=20230601; t=1701277202; x=1701882002; darn=kvack.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=U8mgkS00IbNP5jyZ+NO8ODgKFBs6g0ytgBOeKMTZ8ns=; b=1RQ791TpsX3g/UgSXA5F2KstusnEA0vWNh4adCwDZbX97EuctzMQBwJi9LqPKcPn0C RblZlOvXD1bPdInyor4oW3nVExwulPfK207xAvlYslEz4tNrJ+tvg3QUoO6LEi9UCdEs UWWnd099t1u76ltgG956Ldfi3jqRDHT3Ag3hbwIqJ+NEqIWkACzBt4GlNKxxrfIV1DZH gVLRC3Zi3QbVS7YDMlAF4+ZBMMlRoJIu3Uz8919Y1lxVMKN1v0JHZAilx0BC0+ogbRMa gN403IPKIPG3EREJXalRjzwe+qFB5l4hFYXujboFx5L2snKIgQCF0Z6whIKBxxjDh/0n 9IRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701277202; x=1701882002; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=U8mgkS00IbNP5jyZ+NO8ODgKFBs6g0ytgBOeKMTZ8ns=; b=YCvkjBzZ72xxDs3AdZEX/AeeE6kexfwU5OVS23cOa/UjHHCeeMhRXfM0dE3KlQ+bpv CuyQQjTgwl1KWm2ILGlGlN/0IrAsBGg54HuZg3OPG7CFcrBASN1RBEHr9S2XH66+4xFY Rco7i30AiOF7z1vfxyXriGR/VKiAcvGTkzYICb5+Cd/1MbtIFrqJI8PUJmlXpJdjaS1d KtlpMf1XwHgwW1HqYQb/w29LrdXPX8zWNf+/8wDmsjOXLH/BrNyWpDP8tbx3Xi/RihqV mLkpTvBCr9jQJoS0xGzRHOU3pcM5aTCa1a0PF/4lJP78ojKIKF+u/eH/SbN42v8xl4ST 8RhQ== X-Gm-Message-State: AOJu0YxXi+NZvN8cdIsOSpqr9iYg/IqQiUfZ3sh4evhO0KczAfCOcWhV 7FZYB8Z0RbVLB7ks7usC1UDsXg== X-Google-Smtp-Source: AGHT+IFMmcjiCa+i8CW0+x0EBy+ZJodS4kAFY34IuEihW6YJGVum8lmU2DvIyHxJC59g78xXhTu4kQ== X-Received: by 2002:a05:620a:2707:b0:77d:a0ee:f196 with SMTP id b7-20020a05620a270700b0077da0eef196mr14597254qkp.5.1701277202618; Wed, 29 Nov 2023 09:00:02 -0800 (PST) Received: from localhost ([2620:10d:c091:400::5:ffba]) by smtp.gmail.com with ESMTPSA id rg7-20020a05620a8ec700b0077d8622ee6csm4397763qkn.81.2023.11.29.09.00.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Nov 2023 09:00:02 -0800 (PST) Date: Wed, 29 Nov 2023 12:00:01 -0500 From: Johannes Weiner To: Nhat Pham Cc: akpm@linux-foundation.org, cerasuolodomenico@gmail.com, yosryahmed@google.com, sjenning@redhat.com, ddstreet@ieee.org, vitaly.wool@konsulko.com, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, chrisl@kernel.org, linux-mm@kvack.org, kernel-team@meta.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, shuah@kernel.org Subject: Re: [PATCH v7 2/6] memcontrol: add a new function to traverse online-only memcg hierarchy Message-ID: <20231129170001.GF135852@cmpxchg.org> References: <20231127234600.2971029-1-nphamcs@gmail.com> <20231127234600.2971029-3-nphamcs@gmail.com> <20231129150403.GB135852@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231129150403.GB135852@cmpxchg.org> X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 994B61C000E X-Stat-Signature: r43scdcm7kqoxekpe78rxqb1dzybzzbc X-Rspam-User: X-HE-Tag: 1701277203-474436 X-HE-Meta: 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 K6gfp0Qp 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 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 Wed, Nov 29, 2023 at 10:04:05AM -0500, Johannes Weiner wrote: > On Mon, Nov 27, 2023 at 03:45:56PM -0800, Nhat Pham wrote: > > The new zswap writeback scheme requires an online-only memcg hierarchy > > traversal. Add this functionality via the new mem_cgroup_iter_online() > > function - the old mem_cgroup_iter() is a special case of this new > > function. > > > > Suggested-by: Andrew Morton > > Signed-off-by: Nhat Pham > > Acked-by: Johannes Weiner I saw Michal's reply on the other thread only after I sent this. I agree with him it would be better to just check mem_cgroup_online() in the shinker callsite and leave mem_cgroup_iter() as-is. If it's offline, just continue to the next mem_cgroup_iter() invocation.