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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 B4D67C43331 for ; Sat, 28 Mar 2020 01:48:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A3DA206F6 for ; Sat, 28 Mar 2020 01:48:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="X7+NWtTs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727115AbgC1BsH (ORCPT ); Fri, 27 Mar 2020 21:48:07 -0400 Received: from us-smtp-delivery-74.mimecast.com ([216.205.24.74]:27324 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726518AbgC1BsH (ORCPT ); Fri, 27 Mar 2020 21:48:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585360085; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc; bh=R6EnIywgtvf71A2eQ8RWwmDn7nSMDNR47JwHxvv8GsI=; b=X7+NWtTsgdFWthWLiMy2kAlqVQdrtr4X7XsLBEwOYpwXDyRsJKiim3HN0klMl144iWu5Di lkkU6Qykahs2DLZvp2y3bfWQIBPhRhJPA3fSpI32c/XXQeli6VZffl3jgJLVBioOTenI50 Qnp82FxtYOIoycwbfk0iIdibUcZOr3k= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-447-dVaTkxRaP7SZ50bnrInFFw-1; Fri, 27 Mar 2020 21:48:02 -0400 X-MC-Unique: dVaTkxRaP7SZ50bnrInFFw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6186D190B2A7; Sat, 28 Mar 2020 01:47:59 +0000 (UTC) Received: from llong.com (ovpn-117-95.rdu2.redhat.com [10.10.117.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7301810016DA; Sat, 28 Mar 2020 01:47:55 +0000 (UTC) From: Waiman Long To: Tejun Heo , Li Zefan , Johannes Weiner , Jonathan Corbet Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, Joel Fernandes , Sonny Rao , Waiman Long Subject: [PATCH] docs: cgroup-v1: Document the cpuset_v2_mode mount option Date: Fri, 27 Mar 2020 21:47:48 -0400 Message-Id: <20200328014748.24140-1-longman@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The cpuset in cgroup v1 accepts a special "cpuset_v2_mode" mount option that make cpuset.cpus and cpuset.mems behave more like those in cgroup v2. Document it to make other people more aware of this feature that can be useful in some circumstances. Signed-off-by: Waiman Long --- Documentation/admin-guide/cgroup-v1/cpusets.rst | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/admin-guide/cgroup-v1/cpusets.rst b/Documentation/admin-guide/cgroup-v1/cpusets.rst index 86a6ae995d54..7ade3abd342a 100644 --- a/Documentation/admin-guide/cgroup-v1/cpusets.rst +++ b/Documentation/admin-guide/cgroup-v1/cpusets.rst @@ -223,6 +223,17 @@ cpu_online_mask using a CPU hotplug notifier, and the mems file automatically tracks the value of node_states[N_MEMORY]--i.e., nodes with memory--using the cpuset_track_online_nodes() hook. +The cpuset.effective_cpus and cpuset.effective_mems files are +normally read-only copies of cpuset.cpus and cpuset.mems files +respectively. If the cpuset cgroup filesystem is mounted with the +special "cpuset_v2_mode" option, the behavior of these files will become +similar to the corresponding files in cpuset v2. In other words, hotplug +events will not change cpuset.cpus and cpuset.mems. Those events will +only affect cpuset.effective_cpus and cpuset.effective_mems which show +the actual cpus and memory nodes that are currently used by this cpuset. +See Documentation/admin-guide/cgroup-v2.rst for more information about +cpuset v2 behavior. + 1.4 What are exclusive cpusets ? -------------------------------- -- 2.18.1