Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b395890a authored by Li Zefan's avatar Li Zefan Committed by Tejun Heo
Browse files

cgroup: rename cgroup_pidlist->mutex 



It's a rw_semaphore not a mutex.

Signed-off-by: default avatarLi Zefan <lizefan@huawei.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 876ede8b

kernel/cgroup.c

+11 −11
Original line number Diff line number Diff line
@@ -3436,7 +3436,7 @@ struct cgroup_pidlist { 
	/* pointer to the cgroup we belong to, for list removal purposes */

	struct cgroup *owner;

	/* protects the other fields */

	struct rw_semaphore mutex;

	struct rw_semaphore rwsem;

};



/*
@@ -3509,7 +3509,7 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, 
	struct pid_namespace *ns = task_active_pid_ns(current);



	/*

	 * We can't drop the pidlist_mutex before taking the l->mutex in case

	 * We can't drop the pidlist_mutex before taking the l->rwsem in case

	 * the last ref-holder is trying to remove l from the list at the same

	 * time. Holding the pidlist_mutex precludes somebody taking whichever

	 * list we find out from under us - compare release_pid_array().
@@ -3518,7 +3518,7 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, 
	list_for_each_entry(l, &cgrp->pidlists, links) {

		if (l->key.type == type && l->key.ns == ns) {

			/* make sure l doesn't vanish out from under us */

			down_write(&l->mutex);

			down_write(&l->rwsem);

			mutex_unlock(&cgrp->pidlist_mutex);

			return l;

		}
@@ -3529,8 +3529,8 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, 
		mutex_unlock(&cgrp->pidlist_mutex);

		return l;

	}

	init_rwsem(&l->mutex);

	down_write(&l->mutex);

	init_rwsem(&l->rwsem);

	down_write(&l->rwsem);

	l->key.type = type;

	l->key.ns = get_pid_ns(ns);

	l->owner = cgrp;
@@ -3591,7 +3591,7 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type, 
	l->list = array;

	l->length = length;

	l->use_count++;

	up_write(&l->mutex);

	up_write(&l->rwsem);

	*lp = l;

	return 0;

}
@@ -3669,7 +3669,7 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos) 
	int index = 0, pid = *pos;

	int *iter;



	down_read(&l->mutex);

	down_read(&l->rwsem);

	if (pid) {

		int end = l->length;
@@ -3696,7 +3696,7 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos) 
static void cgroup_pidlist_stop(struct seq_file *s, void *v)

{

	struct cgroup_pidlist *l = s->private;

	up_read(&l->mutex);

	up_read(&l->rwsem);

}



static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos)
@@ -3742,7 +3742,7 @@ static void cgroup_release_pid_array(struct cgroup_pidlist *l) 
	 * pidlist_mutex, we have to take pidlist_mutex first.

	 */

	mutex_lock(&l->owner->pidlist_mutex);

	down_write(&l->mutex);

	down_write(&l->rwsem);

	BUG_ON(!l->use_count);

	if (!--l->use_count) {

		/* we're the last user if refcount is 0; remove and free */
@@ -3750,12 +3750,12 @@ static void cgroup_release_pid_array(struct cgroup_pidlist *l) 
		mutex_unlock(&l->owner->pidlist_mutex);

		pidlist_free(l->list);

		put_pid_ns(l->key.ns);

		up_write(&l->mutex);

		up_write(&l->rwsem);

		kfree(l);

		return;

	}

	mutex_unlock(&l->owner->pidlist_mutex);

	up_write(&l->mutex);

	up_write(&l->rwsem);

}



static int cgroup_pidlist_release(struct inode *inode, struct file *file)