From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 5.12 22/43] cgroup: disable controllers at parse time Date: Thu, 3 Jun 2021 13:07:12 -0400 Message-ID: <20210603170734.3168284-22-sashal@kernel.org> References: <20210603170734.3168284-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622740082; bh=gK/PIRaPplH2AOarruFJFMSYjmI7TyAu/ZGffVNZ/Hg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nca+oe/32a5jCNb0Wp5FU913YPNKWEdMqt8gATMhemYoqF4vUo3ymLXyzoNz/jRQW LkUkxEwdghUv9r7CNne419Ac4rHZCpuJHU11h0+kIU/co7tfUSvPPYqxeCCba/5XZ8 k9ThfIT+OepRhtXDFlf0J/8Vw48vtrYi7PeJ9/hCecPhJrZADInkykRhv+0MPGlxyZ ZvCKRCqK73qAvUrKpEpsQCWPu42DQ5xYUFMczYQwnzs6TIPpcLhih42PeLw+GLLcTU ifFllCyrk8kOXX7vQ5LBKTd+qYXZrxPR8xADKkUd9I7pC3qNzqVIn7sbvb/5NiiVap sO4irEXoD4Crw== In-Reply-To: <20210603170734.3168284-1-sashal-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-ID: Content-Type: text/plain; charset="utf-8" To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Shakeel Butt , NOMURA JUNICHI , Tejun Heo , Sasha Levin , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org From: Shakeel Butt [ Upstream commit 45e1ba40837ac2f6f4d4716bddb8d44bd7e4a251 ] This patch effectively reverts the commit a3e72739b7a7 ("cgroup: fix too early usage of static_branch_disable()"). The commit 6041186a3258 ("init: initialize jump labels before command line option parsing") has moved the jump_label_init() before parse_args() which has made the commit a3e72739b7a7 unnecessary. On the other hand there are consequences of disabling the controllers later as there are subsystems doing the controller checks for different decisions. One such incident is reported [1] regarding the memory controller and its impact on memory reclaim code. [1] https://lore.kernel.org/linux-mm/921e53f3-4b13-aab8-4a9e-e83ff15371e4-YMj9X0ASwKA@public.gmane.org Signed-off-by: Shakeel Butt Reported-by: NOMURA JUNICHI(野村　淳一) Signed-off-by: Tejun Heo Tested-by: Jun'ichi Nomura Signed-off-by: Sasha Levin --- kernel/cgroup/cgroup.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 9153b20e5cc6..2529d1f88330 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5626,8 +5626,6 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; - /** * cgroup_init - cgroup initialization * @@ -5686,12 +5684,8 @@ int __init cgroup_init(void) * disabled flag and cftype registration needs kmalloc, * both of which aren't available during early_init. */ - if (cgroup_disable_mask & (1 << ssid)) { - static_branch_disable(cgroup_subsys_enabled_key[ssid]); - printk(KERN_INFO "Disabling %s control group subsystem\n", - ss->name); + if (!cgroup_ssid_enabled(ssid)) continue; - } if (cgroup1_ssid_disabled(ssid)) printk(KERN_INFO "Disabling %s control group subsystem in v1 mounts\n", @@ -6206,7 +6200,10 @@ static int __init cgroup_disable(char *str) if (strcmp(token, ss->name) && strcmp(token, ss->legacy_name)) continue; - cgroup_disable_mask |= 1 << i; + + static_branch_disable(cgroup_subsys_enabled_key[i]); + pr_info("Disabling %s control group subsystem\n", + ss->name); } } return 1; -- 2.30.2 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 X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E2D0C47082 for ; Thu, 3 Jun 2021 17:08:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E87E6140C for ; Thu, 3 Jun 2021 17:08:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231871AbhFCRKZ (ORCPT ); Thu, 3 Jun 2021 13:10:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:40884 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231262AbhFCRJr (ORCPT ); Thu, 3 Jun 2021 13:09:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 70DB1613F4; Thu, 3 Jun 2021 17:08:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622740082; bh=gK/PIRaPplH2AOarruFJFMSYjmI7TyAu/ZGffVNZ/Hg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nca+oe/32a5jCNb0Wp5FU913YPNKWEdMqt8gATMhemYoqF4vUo3ymLXyzoNz/jRQW LkUkxEwdghUv9r7CNne419Ac4rHZCpuJHU11h0+kIU/co7tfUSvPPYqxeCCba/5XZ8 k9ThfIT+OepRhtXDFlf0J/8Vw48vtrYi7PeJ9/hCecPhJrZADInkykRhv+0MPGlxyZ ZvCKRCqK73qAvUrKpEpsQCWPu42DQ5xYUFMczYQwnzs6TIPpcLhih42PeLw+GLLcTU ifFllCyrk8kOXX7vQ5LBKTd+qYXZrxPR8xADKkUd9I7pC3qNzqVIn7sbvb/5NiiVap sO4irEXoD4Crw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Shakeel Butt , NOMURA JUNICHI , Tejun Heo , Sasha Levin , cgroups@vger.kernel.org Subject: [PATCH AUTOSEL 5.12 22/43] cgroup: disable controllers at parse time Date: Thu, 3 Jun 2021 13:07:12 -0400 Message-Id: <20210603170734.3168284-22-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210603170734.3168284-1-sashal@kernel.org> References: <20210603170734.3168284-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shakeel Butt [ Upstream commit 45e1ba40837ac2f6f4d4716bddb8d44bd7e4a251 ] This patch effectively reverts the commit a3e72739b7a7 ("cgroup: fix too early usage of static_branch_disable()"). The commit 6041186a3258 ("init: initialize jump labels before command line option parsing") has moved the jump_label_init() before parse_args() which has made the commit a3e72739b7a7 unnecessary. On the other hand there are consequences of disabling the controllers later as there are subsystems doing the controller checks for different decisions. One such incident is reported [1] regarding the memory controller and its impact on memory reclaim code. [1] https://lore.kernel.org/linux-mm/921e53f3-4b13-aab8-4a9e-e83ff15371e4@nec.com Signed-off-by: Shakeel Butt Reported-by: NOMURA JUNICHI(野村　淳一) Signed-off-by: Tejun Heo Tested-by: Jun'ichi Nomura Signed-off-by: Sasha Levin --- kernel/cgroup/cgroup.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 9153b20e5cc6..2529d1f88330 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5626,8 +5626,6 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; - /** * cgroup_init - cgroup initialization * @@ -5686,12 +5684,8 @@ int __init cgroup_init(void) * disabled flag and cftype registration needs kmalloc, * both of which aren't available during early_init. */ - if (cgroup_disable_mask & (1 << ssid)) { - static_branch_disable(cgroup_subsys_enabled_key[ssid]); - printk(KERN_INFO "Disabling %s control group subsystem\n", - ss->name); + if (!cgroup_ssid_enabled(ssid)) continue; - } if (cgroup1_ssid_disabled(ssid)) printk(KERN_INFO "Disabling %s control group subsystem in v1 mounts\n", @@ -6206,7 +6200,10 @@ static int __init cgroup_disable(char *str) if (strcmp(token, ss->name) && strcmp(token, ss->legacy_name)) continue; - cgroup_disable_mask |= 1 << i; + + static_branch_disable(cgroup_subsys_enabled_key[i]); + pr_info("Disabling %s control group subsystem\n", + ss->name); } } return 1; -- 2.30.2