cgroup_freezer: trivial cleanups

* Clean-up indentation and line-breaks.  Drop the invalid comment
  about freezer->lock.

* Make all internal functions take @freezer instead of both @cgroup
  and @freezer.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>

kernel/cgroup_freezer.c

@@ -31,14 +31,12 @@ enum freezer_state {
 struct freezer {
 	struct cgroup_subsys_state	css;
 	enum freezer_state		state;
-	spinlock_t lock; /* protects _writes_ to state */
+	spinlock_t			lock;
 };
 
-static inline struct freezer *cgroup_freezer(
-		struct cgroup *cgroup)
+static inline struct freezer *cgroup_freezer(struct cgroup *cgroup)
 {
-	return container_of(
-		cgroup_subsys_state(cgroup, freezer_subsys_id),
+	return container_of(cgroup_subsys_state(cgroup, freezer_subsys_id),
 			    struct freezer, css);
 }
 
@@ -180,8 +178,9 @@ static void freezer_fork(struct task_struct *task)
  * migrated into or out of @cgroup, so we can't verify task states against
  * @freezer state here.  See freezer_attach() for details.
  */
-static void update_if_frozen(struct cgroup *cgroup, struct freezer *freezer)
+static void update_if_frozen(struct freezer *freezer)
 {
+	struct cgroup *cgroup = freezer->css.cgroup;
 	struct cgroup_iter it;
 	struct task_struct *task;
 
@@ -211,12 +210,11 @@ static void update_if_frozen(struct cgroup *cgroup, struct freezer *freezer)
 static int freezer_read(struct cgroup *cgroup, struct cftype *cft,
 			struct seq_file *m)
 {
-	struct freezer *freezer;
+	struct freezer *freezer = cgroup_freezer(cgroup);
 	enum freezer_state state;
 
-	freezer = cgroup_freezer(cgroup);
 	spin_lock_irq(&freezer->lock);
-	update_if_frozen(cgroup, freezer);
+	update_if_frozen(freezer);
 	state = freezer->state;
 	spin_unlock_irq(&freezer->lock);
 
@@ -225,8 +223,9 @@ static int freezer_read(struct cgroup *cgroup, struct cftype *cft,
 	return 0;
 }
 
-static void freeze_cgroup(struct cgroup *cgroup, struct freezer *freezer)
+static void freeze_cgroup(struct freezer *freezer)
 {
+	struct cgroup *cgroup = freezer->css.cgroup;
 	struct cgroup_iter it;
 	struct task_struct *task;
 
@@ -236,8 +235,9 @@ static void freeze_cgroup(struct cgroup *cgroup, struct freezer *freezer)
 	cgroup_iter_end(cgroup, &it);
 }
 
-static void unfreeze_cgroup(struct cgroup *cgroup, struct freezer *freezer)
+static void unfreeze_cgroup(struct freezer *freezer)
 {
+	struct cgroup *cgroup = freezer->css.cgroup;
 	struct cgroup_iter it;
 	struct task_struct *task;
 
@@ -247,11 +247,9 @@ static void unfreeze_cgroup(struct cgroup *cgroup, struct freezer *freezer)
 	cgroup_iter_end(cgroup, &it);
 }
 
-static void freezer_change_state(struct cgroup *cgroup,
+static void freezer_change_state(struct freezer *freezer,
 				 enum freezer_state goal_state)
 {
-	struct freezer *freezer = cgroup_freezer(cgroup);
-
 	/* also synchronizes against task migration, see freezer_attach() */
 	spin_lock_irq(&freezer->lock);
 
@@ -260,13 +258,13 @@ static void freezer_change_state(struct cgroup *cgroup,
 		if (freezer->state != CGROUP_THAWED)
 			atomic_dec(&system_freezing_cnt);
 		freezer->state = CGROUP_THAWED;
-		unfreeze_cgroup(cgroup, freezer);
+		unfreeze_cgroup(freezer);
 		break;
 	case CGROUP_FROZEN:
 		if (freezer->state == CGROUP_THAWED)
 			atomic_inc(&system_freezing_cnt);
 		freezer->state = CGROUP_FREEZING;
-		freeze_cgroup(cgroup, freezer);
+		freeze_cgroup(freezer);
 		break;
 	default:
 		BUG();
@@ -275,8 +273,7 @@ static void freezer_change_state(struct cgroup *cgroup,
 	spin_unlock_irq(&freezer->lock);
 }
 
-static int freezer_write(struct cgroup *cgroup,
-			 struct cftype *cft,
+static int freezer_write(struct cgroup *cgroup, struct cftype *cft,
 			 const char *buffer)
 {
 	enum freezer_state goal_state;
@@ -288,7 +285,7 @@ static int freezer_write(struct cgroup *cgroup,
 	else
 		return -EINVAL;
 
-	freezer_change_state(cgroup, goal_state);
+	freezer_change_state(cgroup_freezer(cgroup), goal_state);
 	return 0;
 }