From: Roman Gushchin <guroan@gmail.com>
To: Tejun Heo <tj@kernel.org>, Oleg Nesterov <oleg@redhat.com>
Cc: Roman Gushchin <guro@fb.com>,
kernel-team@fb.com, cgroups@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH v9 2/9] cgroup: implement __cgroup_task_count() helper
Date: Sat, 16 Mar 2019 10:58:05 -0700 [thread overview]
Message-ID: <20190316175812.6787-3-guro@fb.com> (raw)
In-Reply-To: <20190316175812.6787-1-guro@fb.com>
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 <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
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 583b969b0c0e..29c0ca8f76cf 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -339,22 +339,6 @@ 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 f4418371c83b..b230afccf635 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -592,6 +592,39 @@ 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;
--
2.20.1
next prev parent reply other threads:[~2019-03-16 17:59 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-16 17:58 [PATCH v9 0/9] freezer for cgroup v2 Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 1/9] cgroup: rename freezer.c into legacy_freezer.c Roman Gushchin
2019-03-16 17:58 ` Roman Gushchin [this message]
2019-03-16 17:58 ` [PATCH v9 3/9] cgroup: protect cgroup->nr_(dying_)descendants by css_set_lock Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 4/9] cgroup: cgroup v2 freezer Roman Gushchin
2019-04-02 16:02 ` Oleg Nesterov
2019-04-02 22:08 ` Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 5/9] kselftests: cgroup: don't fail on cg_kill_all() error in cg_destroy() Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 6/9] kselftests: cgroup: add freezer controller self-tests Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 7/9] cgroup: make TRACE_CGROUP_PATH irq-safe Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 8/9] cgroup: add tracing points for cgroup v2 freezer Roman Gushchin
2019-03-16 17:58 ` [PATCH v9 9/9] cgroup: document cgroup v2 freezer interface Roman Gushchin
2019-03-25 16:59 ` [PATCH v9 0/9] freezer for cgroup v2 Roman Gushchin
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