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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FROM,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 F298BC43387 for ; Sat, 22 Dec 2018 00:03:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C307E21928 for ; Sat, 22 Dec 2018 00:03:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kJwGFDCt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404652AbeLVADY (ORCPT ); Fri, 21 Dec 2018 19:03:24 -0500 Received: from mail-pl1-f195.google.com ([209.85.214.195]:43751 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404127AbeLVADT (ORCPT ); Fri, 21 Dec 2018 19:03:19 -0500 Received: by mail-pl1-f195.google.com with SMTP id gn14so3158331plb.10; Fri, 21 Dec 2018 16:03:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=mvoTTqePPOt3Bq4d9Skj0YSKEIcvqgD14v+eA23Gmu0=; b=kJwGFDCtuUu22XvgCASPd5aQpVLY5SOIZy8lm6PM13SbizDkHnFVzZI5NH+yJWfj0V UROwuVVNAgZ1RdlmfVpM3SqLvqw8P9nPFt3OfA6aafTmWduvAnMv+AskCObv6MFjd8GT AGqAw7O7N57m3ssuAgrIMfyDneIJY1jgM5e7IRMU1IWOVEvM16lwkNYE7AVz8EJRcLeN fI+vRN4OETrz4vNXhgf9Yal3y9iQ1S5CgRY+F0/CykLVmMPYTK6VB+N3o9WhE7zND68Y ImMXBkp7FbCtmfl85Ksz386t//MT2wPJuIluSo2/yE2O108T2RZQfQFLy1obtcn/yVRo 3Psg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=mvoTTqePPOt3Bq4d9Skj0YSKEIcvqgD14v+eA23Gmu0=; b=mu+Uj/JIyQNBQQtUJhN+KhGeITw+ha6Iw6XvByy8+tRnoeJbRlEszmP+YJ4IqaBfsJ 17aPjA1icZ2psaHmhNqkTD9tSEj170DQ4ILjbruFhqG/aByZ/S1uFbnWk6QJ4NQF7rdo r7sE3vGus5qjdkz7lgHA9HuS9HUlTp1X+DDH5gWs5t+1TA9bFkv11/R5rNS//crBpemI CkS3D2xDbZtImuoAiwNzGoAo4+EvqSt0lGyOQH2qUKG2rPU9Q/Vxxx0C+dIqyoXjCDyp u/KG4KX6DeCWBNUSyaf9jAlDYfJbNyoYTrlHUDlCHnGmY1mUbTlQ4rBuNEimIsWzADUg iwTA== X-Gm-Message-State: AJcUukeLXy/JNWCsqjByYIiPoDzmq4I+TA4T49Yared4KNWqGPDD4TWO Qt+G/FV94tXo9Oyejuq/hNk= X-Google-Smtp-Source: ALg8bN4OtXnzql/JtGefZH3drcan1qn1HWBvI0mHz825swZDtmwfJ6590gAjWvpYI0ShJxgWJBwnhg== X-Received: by 2002:a17:902:f01:: with SMTP id 1mr4390343ply.143.1545436998419; Fri, 21 Dec 2018 16:03:18 -0800 (PST) Received: from tower.thefacebook.com ([2620:10d:c090:200::7:608f]) by smtp.gmail.com with ESMTPSA id 83sm36659266pgf.57.2018.12.21.16.03.17 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 21 Dec 2018 16:03:17 -0800 (PST) From: Roman Gushchin X-Google-Original-From: Roman Gushchin To: Tejun Heo , Oleg Nesterov Cc: kernel-team@fb.com, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Roman Gushchin , linux-doc@vger.kernel.org Subject: [PATCH v6 7/7] cgroup: document cgroup v2 freezer interface Date: Fri, 21 Dec 2018 16:03:07 -0800 Message-Id: <20181222000307.28231-8-guro@fb.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181222000307.28231-1-guro@fb.com> References: <20181222000307.28231-1-guro@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Describe cgroup v2 freezer interface in the cgroup v2 admin guide. Signed-off-by: Roman Gushchin Reviewed-by: Mike Rapoport Cc: Tejun Heo Cc: linux-doc@vger.kernel.org Cc: kernel-team@fb.com --- Documentation/admin-guide/cgroup-v2.rst | 27 +++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 07e06136a550..f8335e26b362 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -864,6 +864,8 @@ All cgroup core files are prefixed with "cgroup." populated 1 if the cgroup or its descendants contains any live processes; otherwise, 0. + frozen + 1 if the cgroup is frozen; otherwise, 0. cgroup.max.descendants A read-write single value files. The default is "max". @@ -897,6 +899,31 @@ All cgroup core files are prefixed with "cgroup." A dying cgroup can consume system resources not exceeding limits, which were active at the moment of cgroup deletion. + cgroup.freeze + A read-write single value file which exists on non-root cgroups. + Allowed values are "0" and "1". The default is "0". + + Writing "1" to the file causes freezing of the cgroup and all + descendant cgroups. This means that all belonging processes will + be stopped and will not run until the cgroup will be explicitly + unfrozen. Freezing of the cgroup may take some time; when this action + is completed, the "frozen" value in the cgroup.events control file + will be updated to "1" and the corresponding notification will be + issued. + + A cgroup can be frozen either by its own settings, or by settings + of any ancestor cgroups. If any of ancestor cgroups is frozen, the + cgroup will remain frozen. + + Processes in the frozen cgroup can be killed by a fatal signal. + They also can enter and leave a frozen cgroup: either by an explicit + move by a user, or if freezing of the cgroup races with fork(). + If a process is moved to a frozen cgroup, it stops. If a process is + moved out of a frozen cgroup, it becomes running. + + Frozen status of a cgroup doesn't affect any cgroup tree operations: + it's possible to delete a frozen (and empty) cgroup, as well as + create new sub-cgroups. Controllers =========== -- 2.19.2