cgroup: revert ss_id_lock to spinlock

[platform/adaptation/renesas_rcar/renesas_kernel.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index c6877fe..8eb90f2 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4885,9 +4885,9 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
 
        rcu_assign_pointer(id->css, NULL);
        rcu_assign_pointer(css->id, NULL);
-       write_lock(&ss->id_lock);
+       spin_lock(&ss->id_lock);
        idr_remove(&ss->idr, id->id);
-       write_unlock(&ss->id_lock);
+       spin_unlock(&ss->id_lock);
        kfree_rcu(id, rcu_head);
 }
 EXPORT_SYMBOL_GPL(free_css_id);
@@ -4913,10 +4913,10 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
                error = -ENOMEM;
                goto err_out;
        }
-       write_lock(&ss->id_lock);
+       spin_lock(&ss->id_lock);
        /* Don't use 0. allocates an ID of 1-65535 */
        error = idr_get_new_above(&ss->idr, newid, 1, &myid);
-       write_unlock(&ss->id_lock);
+       spin_unlock(&ss->id_lock);
 
        /* Returns error when there are no free spaces for new ID.*/
        if (error) {
@@ -4931,9 +4931,9 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
        return newid;
 remove_idr:
        error = -ENOSPC;
-       write_lock(&ss->id_lock);
+       spin_lock(&ss->id_lock);
        idr_remove(&ss->idr, myid);
-       write_unlock(&ss->id_lock);
+       spin_unlock(&ss->id_lock);
 err_out:
        kfree(newid);
        return ERR_PTR(error);
@@ -4945,7 +4945,7 @@ static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss,
 {
        struct css_id *newid;
 
-       rwlock_init(&ss->id_lock);
+       spin_lock_init(&ss->id_lock);
        idr_init(&ss->idr);
 
        newid = get_new_cssid(ss, 0);
@@ -5040,9 +5040,9 @@ css_get_next(struct cgroup_subsys *ss, int id,
                 * scan next entry from bitmap(tree), tmpid is updated after
                 * idr_get_next().
                 */
-               read_lock(&ss->id_lock);
+               spin_lock(&ss->id_lock);
                tmp = idr_get_next(&ss->idr, &tmpid);
-               read_unlock(&ss->id_lock);
+               spin_unlock(&ss->id_lock);
 
                if (!tmp)
                        break;