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 4E148C433EF for ; Fri, 10 Jun 2022 23:01:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 68E766B0166; Fri, 10 Jun 2022 19:01:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 63DDE6B0167; Fri, 10 Jun 2022 19:01:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 506208D00E2; Fri, 10 Jun 2022 19:01:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 3EAD76B0166 for ; Fri, 10 Jun 2022 19:01:58 -0400 (EDT) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 0E7BC34FB1 for ; Fri, 10 Jun 2022 23:01:58 +0000 (UTC) X-FDA: 79563850716.20.72F1502 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf24.hostedemail.com (Postfix) with ESMTP id 634E418006D for ; Fri, 10 Jun 2022 23:01:57 +0000 (UTC) Date: Fri, 10 Jun 2022 16:01:49 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1654902115; 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=o/6mUBgZNpbkGWs/QZgEhqh7EhqSsLFJVzEHebhLLQ4=; b=PnfPfdpvq7qb1g0zYrY/UVmlMtf6qD7NeI5CnBHO8P6J9B3BR5z5axnlGN+hN5BUmBlis9 sI0zeOhSZqywW1ercqgEpcbAcoVS+g9Wqz8CJ4R5pLQI4UG5qqMMwzXBV049TfrMJAY14K rBUevuGY7TKG/zIg0hHGKtU5Lr7f9G4= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Roman Gushchin To: Muchun Song Cc: hannes@cmpxchg.org, mhocko@kernel.org, shakeelb@google.com, akpm@linux-foundation.org, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, duanxiongchun@bytedance.com, longman@redhat.com Subject: Re: [PATCH v5 01/11] mm: memcontrol: remove dead code and comments Message-ID: References: <20220530074919.46352-1-songmuchun@bytedance.com> <20220530074919.46352-2-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220530074919.46352-2-songmuchun@bytedance.com> X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1654902117; a=rsa-sha256; cv=none; b=D3+OvvKU/gGBE84lKBSgkIb7k4GKXCiixXEzYLZvBplOLz+XTP+gtQi/oM54rQwmDHsUoe F87NnxDekXVTFW5hDXU/RiCnGW/wQCgFtvMEbNzorwLfA/RsoHBKP7NygcwpvftID60i9g F+yvrZ5071Q3OsBM4TrlEJarb9xB6X8= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=PnfPfdpv; spf=pass (imf24.hostedemail.com: domain of roman.gushchin@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=roman.gushchin@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=1654902117; 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=o/6mUBgZNpbkGWs/QZgEhqh7EhqSsLFJVzEHebhLLQ4=; b=n+55PEl4OlMj5I7DpY9NkSwAXStAyeDc/XK3FDd+vh21NPrAmCrVOgMSpqLDJ8HwDwbLjM vSmLH+jcW51tcReV0maxU+JknEE961NB/+InzceuwgEyOPkJnVgAIxU+McJ7gVMhoeltpO cNx1/TMxZFdgCxOdxVj2NwwiD+Y3jqc= X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 634E418006D X-Stat-Signature: 4ceg1itubutue3bbbqisqk1ujcporugi X-Rspam-User: Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=PnfPfdpv; spf=pass (imf24.hostedemail.com: domain of roman.gushchin@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=roman.gushchin@linux.dev; dmarc=pass (policy=none) header.from=linux.dev X-HE-Tag: 1654902117-236206 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 Mon, May 30, 2022 at 03:49:09PM +0800, Muchun Song wrote: > Since no-hierarchy mode is deprecated after > > commit bef8620cd8e0 ("mm: memcg: deprecate the non-hierarchical mode") > > so parent_mem_cgroup() cannot return a NULL except root memcg, however, root > memcg cannot be offline, so it is safe to drop the check of returned value > of parent_mem_cgroup(). Remove those dead code. > > The comments in memcg_offline_kmem() above memcg_reparent_list_lrus() are > out of date since > > commit 5abc1e37afa0 ("mm: list_lru: allocate list_lru_one only when needed") > > There is no ordering requirement between memcg_reparent_list_lrus() and > memcg_reparent_objcgs(), so remove those outdated comments. > > Signed-off-by: Muchun Song Acked-by: Roman Gushchin Nice cleanup!