cgroup: rename cgroup_pidlist->mutex

It's a rw_semaphore not a mutex.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 9f6dab22289efce9c6e826ece301331f437ebf1c..9420662df87ee6fab6e1059ae147a56e7d762bf2 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -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)