Commit 541a4219 authored by JP Kobryn's avatar JP Kobryn Committed by Tejun Heo
Browse files

cgroup: compare css to cgroup::self in helper for distingushing css 



Adjust the implementation of css_is_cgroup() so that it compares the given
css to cgroup::self. Rename the function to css_is_self() in order to
reflect that. Change the existing css->ss NULL check to a warning in the
true branch. Finally, adjust call sites to use the new function name.

Signed-off-by: default avatarJP Kobryn <inwardvessel@gmail.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent b2713a5a

include/linux/cgroup.h

+8 −2
Original line number Diff line number Diff line
@@ -347,9 +347,15 @@ static inline bool css_is_dying(struct cgroup_subsys_state *css) 
	return css->flags & CSS_DYING;

}



static inline bool css_is_cgroup(struct cgroup_subsys_state *css)

static inline bool css_is_self(struct cgroup_subsys_state *css)

{

	return css->ss == NULL;

	if (css == &css->cgroup->self) {

		/* cgroup::self should not have subsystem association */

		WARN_ON(css->ss != NULL);

		return true;

	}



	return false;

}



static inline void cgroup_get(struct cgroup *cgrp)

kernel/cgroup/cgroup.c

+4 −4
Original line number Diff line number Diff line
@@ -1706,7 +1706,7 @@ static void css_clear_dir(struct cgroup_subsys_state *css) 


	css->flags &= ~CSS_VISIBLE;



	if (css_is_cgroup(css)) {

	if (css_is_self(css)) {

		if (cgroup_on_dfl(cgrp)) {

			cgroup_addrm_files(css, cgrp,

					   cgroup_base_files, false);
@@ -1738,7 +1738,7 @@ static int css_populate_dir(struct cgroup_subsys_state *css) 
	if (css->flags & CSS_VISIBLE)

		return 0;



	if (css_is_cgroup(css)) {

	if (css_is_self(css)) {

		if (cgroup_on_dfl(cgrp)) {

			ret = cgroup_addrm_files(css, cgrp,

						 cgroup_base_files, true);
@@ -5406,7 +5406,7 @@ static void css_free_rwork_fn(struct work_struct *work) 


	percpu_ref_exit(&css->refcnt);



	if (ss) {

	if (!css_is_self(css)) {

		/* css free path */

		struct cgroup_subsys_state *parent = css->parent;

		int id = css->id;
@@ -5460,7 +5460,7 @@ static void css_release_work_fn(struct work_struct *work) 
	css->flags |= CSS_RELEASED;

	list_del_rcu(&css->sibling);



	if (ss) {

	if (!css_is_self(css)) {

		struct cgroup *parent_cgrp;



		/* css release path */