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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 B86D8ECDE47 for ; Thu, 8 Nov 2018 15:09:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8618F20825 for ; Thu, 8 Nov 2018 15:09:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8618F20825 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727510AbeKIApZ (ORCPT ); Thu, 8 Nov 2018 19:45:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41750 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726672AbeKIApX (ORCPT ); Thu, 8 Nov 2018 19:45:23 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1605D2D7E0; Thu, 8 Nov 2018 15:09:27 +0000 (UTC) Received: from llong.com (dhcp-17-55.bos.redhat.com [10.18.17.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id 40450648C8; Thu, 8 Nov 2018 15:09:25 +0000 (UTC) From: Waiman Long To: Tejun Heo , Li Zefan , Johannes Weiner , Peter Zijlstra , Ingo Molnar Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kernel-team@fb.com, pjt@google.com, luto@amacapital.net, Mike Galbraith , torvalds@linux-foundation.org, Roman Gushchin , Juri Lelli , Patrick Bellasi , Tom Hromatka , Waiman Long Subject: [PATCH v15 10/12] cpuset: Use descriptive text when reading/writing cpuset.sched.partition Date: Thu, 8 Nov 2018 10:08:44 -0500 Message-Id: <1541689726-20088-11-git-send-email-longman@redhat.com> In-Reply-To: <1541689726-20088-1-git-send-email-longman@redhat.com> References: <1541689726-20088-1-git-send-email-longman@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 08 Nov 2018 15:09:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, cpuset.sched.partition returns the values, 0, 1 or -1 on read. A person who is not familiar with the partition code may not understand what they mean. In order to make cpuset.sched.partition more user-friendly, it will now display the following descriptive text on read: "root" - A partition root (top cpuset of a partition) "member" - A non-root member of a partition "root invalid" - An invalid partition root Note that there is at least one partition in the whole cgroup hierarchy. The top cpuset is the root of that partition. The rests are either a root if it starts a new partition or a member of a partition. The cpuset.sched.partition file will now also accept "root" and "member" besides 1 and 0 as valid input values. The "root invalid" value is internal only and cannot be written to the file. Suggested-by: Tejun Heo Signed-off-by: Waiman Long --- kernel/cgroup/cpuset.c | 58 ++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 51 insertions(+), 7 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index fc1a809..c739fda 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -2278,9 +2278,6 @@ static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft, case FILE_SCHED_RELAX_DOMAIN_LEVEL: retval = update_relax_domain_level(cs, val); break; - case FILE_PARTITION_ROOT: - retval = update_prstate(cs, val); - break; default: retval = -EINVAL; break; @@ -2431,8 +2428,6 @@ static s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft) switch (type) { case FILE_SCHED_RELAX_DOMAIN_LEVEL: return cs->relax_domain_level; - case FILE_PARTITION_ROOT: - return cs->partition_root_state; default: BUG(); } @@ -2441,6 +2436,55 @@ static s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft) return 0; } +static int sched_partition_show(struct seq_file *seq, void *v) +{ + struct cpuset *cs = css_cs(seq_css(seq)); + + switch (cs->partition_root_state) { + case PRS_ENABLED: + seq_puts(seq, "root\n"); + break; + case PRS_DISABLED: + seq_puts(seq, "member\n"); + break; + case PRS_ERROR: + seq_puts(seq, "root invalid\n"); + break; + } + return 0; +} + +static ssize_t sched_partition_write(struct kernfs_open_file *of, char *buf, + size_t nbytes, loff_t off) +{ + struct cpuset *cs = css_cs(of_css(of)); + int val; + int retval = -ENODEV; + + buf = strstrip(buf); + + /* + * Convert "root"/"1" to 1, and convert "member"/"0" to 0. + */ + if (!strcmp(buf, "root") || !strcmp(buf, "1")) + val = PRS_ENABLED; + else if (!strcmp(buf, "member") || !strcmp(buf, "0")) + val = PRS_DISABLED; + else + return -EINVAL; + + css_get(&cs->css); + mutex_lock(&cpuset_mutex); + if (!is_cpuset_online(cs)) + goto out_unlock; + + retval = update_prstate(cs, val); +out_unlock: + mutex_unlock(&cpuset_mutex); + css_put(&cs->css); + return retval ?: nbytes; +} + /* * for the common functions, 'private' gives the type of file */ @@ -2584,8 +2628,8 @@ static s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft) { .name = "sched.partition", - .read_s64 = cpuset_read_s64, - .write_s64 = cpuset_write_s64, + .seq_show = sched_partition_show, + .write = sched_partition_write, .private = FILE_PARTITION_ROOT, .flags = CFTYPE_NOT_ON_ROOT, }, -- 1.8.3.1