From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 6B6CF7D8A5 for ; Fri, 7 Dec 2018 20:16:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726079AbeLGUQ1 (ORCPT ); Fri, 7 Dec 2018 15:16:27 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:39598 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726319AbeLGUPi (ORCPT ); Fri, 7 Dec 2018 15:15:38 -0500 Received: by mail-pg1-f196.google.com with SMTP id w6so2177768pgl.6; Fri, 07 Dec 2018 12:15:37 -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; bh=CXMv0Vhrfz8OgUyxnyaG6yJ3Btg8UiW/JMvPPUaP47g=; b=iv1dU8CL7eCxkwjdGBFS0mbtxk6GU8XmzSL0nJFOoIS3VrhbCDGf0tP7iWGdFyLajD aplvV93AwOr0eNpnVx2zfFszUcI9KJzC3oAbVs0+ahZvCFNKy+zAlp8pkxa97NR92hMK pjgD1Fm33eANuoVbsiu7oh7dI0OarvO/14v6gXDwWqljuOHakvlaZDRSXOua3/s8mujq IaDC3x/5XRCDmnhvPaBJZHXh66MAnAM5vF+v0MytJfiEbYunsILafsGbXfnynRIPXzwN ysUrfKuhMeXogcAMnw5sPNpw2f175HdVKRuW7TFFgHtHiu2p3QYsNPAaktOHWdQM1i84 5GQA== 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; bh=CXMv0Vhrfz8OgUyxnyaG6yJ3Btg8UiW/JMvPPUaP47g=; b=btQDsWd1JULN3iU0ESvmHHk6iOnZrTZ8J3thpnMEuPkA+IkDn8dGiBtt11oULNrqF/ ShBjYBcF2XbX7tcXMRdl4o1Avp1jKr2Aqe4YlUZOnNJAdz5PhM4Ks2ptCcmWRRkFWfvb j9Xixqu4cEsSMHXP3NRveHgWMSraLvpzV+dghjG08oSIIAlE6nT9TYiwEMa4daANciRv qQZmwKEq7rt1iFZh15ZQjTDkWACRPe07lSWfPaaM4X2awZISID9A9nn67ixEI7sE7yom 08KugbYhf2yPHK7wxre9yrX7/+wmlX/xZmQeGdVHO3IAzlSimmSdK5GamRYaXTa0rh+J 1EDQ== X-Gm-Message-State: AA+aEWZwjJ5hszgatFjOZsvddGYxSjLbxS1VupJ/pQWtBUi2INdVtuGD VuYZM/CL7Q0A3A9WjVtOB58= X-Google-Smtp-Source: AFSGD/Xzu9bkbeks40O2SGCZiYVYF2PqYn8T+cGanFzGlm74lZiHOkKF33gcr0CIj/VOO2BVdD5/xQ== X-Received: by 2002:a62:2f06:: with SMTP id v6mr3660164pfv.216.1544213736978; Fri, 07 Dec 2018 12:15:36 -0800 (PST) Received: from castle.thefacebook.com ([2620:10d:c090:200::6:d83b]) by smtp.gmail.com with ESMTPSA id q75sm5870898pfa.38.2018.12.07.12.15.36 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 07 Dec 2018 12:15:36 -0800 (PST) From: Roman Gushchin X-Google-Original-From: Roman Gushchin To: Tejun Heo , Oleg Nesterov Cc: Dan Carpenter , Mike Rapoport , cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, Roman Gushchin Subject: [PATCH v5 2/7] cgroup: implement __cgroup_task_count() helper Date: Fri, 7 Dec 2018 12:15:26 -0800 Message-Id: <20181207201531.1665-3-guro@fb.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20181207201531.1665-1-guro@fb.com> References: <20181207201531.1665-1-guro@fb.com> Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org The helper is identical to the existing cgroup_task_count() except it doesn't take the css_set_lock by itself, assuming that the caller does. Also, move cgroup_task_count() implementation into kernel/cgroup/cgroup.c, as there is nothing specific to cgroup v1. Signed-off-by: Roman Gushchin Cc: Tejun Heo Cc: kernel-team@fb.com --- kernel/cgroup/cgroup-internal.h | 1 + kernel/cgroup/cgroup-v1.c | 16 ---------------- kernel/cgroup/cgroup.c | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 34 insertions(+), 16 deletions(-) diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index c950864016e2..a195328431ce 100644 --- a/kernel/cgroup/cgroup-internal.h +++ b/kernel/cgroup/cgroup-internal.h @@ -226,6 +226,7 @@ int cgroup_rmdir(struct kernfs_node *kn); int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node, struct kernfs_root *kf_root); +int __cgroup_task_count(const struct cgroup *cgrp); int cgroup_task_count(const struct cgroup *cgrp); /* diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index 51063e7a93c2..6134fef07d57 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -336,22 +336,6 @@ static struct cgroup_pidlist *cgroup_pidlist_find_create(struct cgroup *cgrp, return l; } -/** - * cgroup_task_count - count the number of tasks in a cgroup. - * @cgrp: the cgroup in question - */ -int cgroup_task_count(const struct cgroup *cgrp) -{ - int count = 0; - struct cgrp_cset_link *link; - - spin_lock_irq(&css_set_lock); - list_for_each_entry(link, &cgrp->cset_links, cset_link) - count += link->cset->nr_tasks; - spin_unlock_irq(&css_set_lock); - return count; -} - /* * Load a cgroup's pidarray with either procs' tgids or tasks' pids */ diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index e06994fd4e34..7519a4307021 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -563,6 +563,39 @@ static void cgroup_get_live(struct cgroup *cgrp) css_get(&cgrp->self); } +/** + * __cgroup_task_count - count the number of tasks in a cgroup. The caller + * is responsible for taking the css_set_lock. + * @cgrp: the cgroup in question + */ +int __cgroup_task_count(const struct cgroup *cgrp) +{ + int count = 0; + struct cgrp_cset_link *link; + + lockdep_assert_held(&css_set_lock); + + list_for_each_entry(link, &cgrp->cset_links, cset_link) + count += link->cset->nr_tasks; + + return count; +} + +/** + * cgroup_task_count - count the number of tasks in a cgroup. + * @cgrp: the cgroup in question + */ +int cgroup_task_count(const struct cgroup *cgrp) +{ + int count; + + spin_lock_irq(&css_set_lock); + count = __cgroup_task_count(cgrp); + spin_unlock_irq(&css_set_lock); + + return count; +} + struct cgroup_subsys_state *of_css(struct kernfs_open_file *of) { struct cgroup *cgrp = of->kn->parent->priv; -- 2.17.2