From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 5.10 20/39] cgroup: disable controllers at parse time Date: Thu, 3 Jun 2021 13:08:10 -0400 Message-ID: <20210603170829.3168708-20-sashal@kernel.org> References: <20210603170829.3168708-1-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=1622740134; bh=oP5uqppbhMT+aMCdFfU/PluXUbOZINnOeEafkkCOHEQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lCpkdBJR17ILU0CbaOoVaxKuSfAQ5luBGxwVihg3FK9HLJiAXDUBzZ0ixuuQOLDIk uCzQuT1RvGJloaIS2kAbV4stAU9/bI2HvGDEQg6+XMV5cfOjSnZzMuDr3UuD0yAJOO ngpdWkzGD+BrYH4TDPV/3U3bUt3nIYaBCxXSNZpSzQEdbHaykp5bkaa8cXKo9dVElq ltJyay8UvIrs5uyO/wZCh9A9wBNejn/YVLq4Dm/Igt7o/Eq2iMmWt8C6rMZYvGNjPB lBRhjp7eIcb94Jsh97ABcOMSnwkm7RkBRMbrgP7uzA4yjNnU/YD2lThsUpIhjyxHNv dfleeGnmUIzGA== In-Reply-To: <20210603170829.3168708-1-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 5d1fdf7c3ec6..c8b811e039cc 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5665,8 +5665,6 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; - /** * cgroup_init - cgroup initialization * @@ -5725,12 +5723,8 @@ 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", @@ -6245,7 +6239,10 @@ 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 4D2ECC4709A for ; Thu, 3 Jun 2021 17:10:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 37B0C61417 for ; Thu, 3 Jun 2021 17:10:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232555AbhFCRMZ (ORCPT ); Thu, 3 Jun 2021 13:12:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:42392 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232078AbhFCRKl (ORCPT ); Thu, 3 Jun 2021 13:10:41 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D8DCE613F8; Thu, 3 Jun 2021 17:08:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622740134; bh=oP5uqppbhMT+aMCdFfU/PluXUbOZINnOeEafkkCOHEQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lCpkdBJR17ILU0CbaOoVaxKuSfAQ5luBGxwVihg3FK9HLJiAXDUBzZ0ixuuQOLDIk uCzQuT1RvGJloaIS2kAbV4stAU9/bI2HvGDEQg6+XMV5cfOjSnZzMuDr3UuD0yAJOO ngpdWkzGD+BrYH4TDPV/3U3bUt3nIYaBCxXSNZpSzQEdbHaykp5bkaa8cXKo9dVElq ltJyay8UvIrs5uyO/wZCh9A9wBNejn/YVLq4Dm/Igt7o/Eq2iMmWt8C6rMZYvGNjPB lBRhjp7eIcb94Jsh97ABcOMSnwkm7RkBRMbrgP7uzA4yjNnU/YD2lThsUpIhjyxHNv dfleeGnmUIzGA== 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 5.10 20/39] cgroup: disable controllers at parse time Date: Thu, 3 Jun 2021 13:08:10 -0400 Message-Id: <20210603170829.3168708-20-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210603170829.3168708-1-sashal@kernel.org> References: <20210603170829.3168708-1-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 5d1fdf7c3ec6..c8b811e039cc 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5665,8 +5665,6 @@ int __init cgroup_init_early(void) return 0; } -static u16 cgroup_disable_mask __initdata; - /** * cgroup_init - cgroup initialization * @@ -5725,12 +5723,8 @@ 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", @@ -6245,7 +6239,10 @@ 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