cgroup: s/cgrp_dfl_root_/cgrp_dfl_/

These var names are unnecessarily unwiedly and another similar
variable will be added.  Let's shorten them.
Signed-off-by: Tejun Heo <tj@kernel.org>

kernel/cgroup.c

@@ -178,13 +178,13 @@ EXPORT_SYMBOL_GPL(cgrp_dfl_root);
  * The default hierarchy always exists but is hidden until mounted for the
  * first time.  This is for backward compatibility.
  */
-static bool cgrp_dfl_root_visible;
+static bool cgrp_dfl_visible;
 
 /* Controllers blocked by the commandline in v1 */
 static u16 cgroup_no_v1_mask;
 
 /* some controllers are not supported in the default hierarchy */
-static u16 cgrp_dfl_root_inhibit_ss_mask;
+static u16 cgrp_dfl_inhibit_ss_mask;
 
 /* The list of hierarchy roots */
 
@@ -1486,7 +1486,7 @@ static int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask)
 	/* skip creating root files on dfl_root for inhibited subsystems */
 	tmp_ss_mask = ss_mask;
 	if (dst_root == &cgrp_dfl_root)
-		tmp_ss_mask &= ~cgrp_dfl_root_inhibit_ss_mask;
+		tmp_ss_mask &= ~cgrp_dfl_inhibit_ss_mask;
 
 	do_each_subsys_mask(ss, ssid, tmp_ss_mask) {
 		struct cgroup *scgrp = &ss->root->cgrp;
@@ -1503,7 +1503,7 @@ static int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask)
 		 * Just warn about it and continue.
 		 */
 		if (dst_root == &cgrp_dfl_root) {
-			if (cgrp_dfl_root_visible) {
+			if (cgrp_dfl_visible) {
 				pr_warn("failed to create files (%d) while rebinding 0x%x to default root\n",
 					ret, ss_mask);
 				pr_warn("you may retry by moving them to a different hierarchy and unbinding\n");
@@ -2006,7 +2006,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
 			pr_err("cgroup2: unknown option \"%s\"\n", (char *)data);
 			return ERR_PTR(-EINVAL);
 		}
-		cgrp_dfl_root_visible = true;
+		cgrp_dfl_visible = true;
 		root = &cgrp_dfl_root;
 		cgroup_get(&root->cgrp);
 		goto out_mount;
@@ -2858,7 +2858,7 @@ static int cgroup_root_controllers_show(struct seq_file *seq, void *v)
 	struct cgroup *cgrp = seq_css(seq)->cgroup;
 
 	cgroup_print_ss_mask(seq, cgrp->root->subsys_mask &
-			     ~cgrp_dfl_root_inhibit_ss_mask);
+			     ~cgrp_dfl_inhibit_ss_mask);
 	return 0;
 }
 
@@ -2962,7 +2962,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
 	while ((tok = strsep(&buf, " "))) {
 		if (tok[0] == '\0')
 			continue;
-		do_each_subsys_mask(ss, ssid, ~cgrp_dfl_root_inhibit_ss_mask) {
+		do_each_subsys_mask(ss, ssid, ~cgrp_dfl_inhibit_ss_mask) {
 			if (!cgroup_ssid_enabled(ssid) ||
 			    strcmp(tok + 1, ss->name))
 				continue;
@@ -5315,7 +5315,7 @@ int __init cgroup_init(void)
 		cgrp_dfl_root.subsys_mask |= 1 << ss->id;
 
 		if (!ss->dfl_cftypes)
-			cgrp_dfl_root_inhibit_ss_mask |= 1 << ss->id;
+			cgrp_dfl_inhibit_ss_mask |= 1 << ss->id;
 
 		if (ss->dfl_cftypes == ss->legacy_cftypes) {
 			WARN_ON(cgroup_add_cftypes(ss, ss->dfl_cftypes));
@@ -5386,7 +5386,7 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns,
 		struct cgroup *cgrp;
 		int ssid, count = 0;
 
-		if (root == &cgrp_dfl_root && !cgrp_dfl_root_visible)
+		if (root == &cgrp_dfl_root && !cgrp_dfl_visible)
 			continue;
 
 		seq_printf(m, "%d:", root->hierarchy_id);