cgroup: remove css_parent()
cgroup in general is moving towards using cgroup_subsys_state as the fundamental structural component and css_parent() was introduced to convert from using cgroup->parent to css->parent. It was quite some time ago and we're moving forward with making css more prominent. This patch drops the trivial wrapper css_parent() and let the users dereference css->parent. While at it, explicitly mark fields of css which are public and immutable. v2: New usage from device_cgroup.c converted. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: "David S. Miller" <davem@davemloft.net> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Johannes Weiner <hannes@cmpxchg.org>
This commit is contained in:
@@ -48,22 +48,28 @@ enum cgroup_subsys_id {
|
||||
};
|
||||
#undef SUBSYS
|
||||
|
||||
/* Per-subsystem/per-cgroup state maintained by the system. */
|
||||
/*
|
||||
* Per-subsystem/per-cgroup state maintained by the system. This is the
|
||||
* fundamental structural building block that controllers deal with.
|
||||
*
|
||||
* Fields marked with "PI:" are public and immutable and may be accessed
|
||||
* directly without synchronization.
|
||||
*/
|
||||
struct cgroup_subsys_state {
|
||||
/* the cgroup that this css is attached to */
|
||||
/* PI: the cgroup that this css is attached to */
|
||||
struct cgroup *cgroup;
|
||||
|
||||
/* the cgroup subsystem that this css is attached to */
|
||||
/* PI: the cgroup subsystem that this css is attached to */
|
||||
struct cgroup_subsys *ss;
|
||||
|
||||
/* reference count - access via css_[try]get() and css_put() */
|
||||
struct percpu_ref refcnt;
|
||||
|
||||
/* the parent css */
|
||||
/* PI: the parent css */
|
||||
struct cgroup_subsys_state *parent;
|
||||
|
||||
/*
|
||||
* Subsys-unique ID. 0 is unused and root is always 1. The
|
||||
* PI: Subsys-unique ID. 0 is unused and root is always 1. The
|
||||
* matching css can be looked up using css_from_id().
|
||||
*/
|
||||
int id;
|
||||
@@ -669,19 +675,6 @@ struct cgroup_subsys {
|
||||
#include <linux/cgroup_subsys.h>
|
||||
#undef SUBSYS
|
||||
|
||||
/**
|
||||
* css_parent - find the parent css
|
||||
* @css: the target cgroup_subsys_state
|
||||
*
|
||||
* Return the parent css of @css. This function is guaranteed to return
|
||||
* non-NULL parent as long as @css isn't the root.
|
||||
*/
|
||||
static inline
|
||||
struct cgroup_subsys_state *css_parent(struct cgroup_subsys_state *css)
|
||||
{
|
||||
return css->parent;
|
||||
}
|
||||
|
||||
/**
|
||||
* task_css_set_check - obtain a task's css_set with extra access conditions
|
||||
* @task: the task to obtain css_set for
|
||||
|
Reference in New Issue
Block a user