cgroup: clean up the cftype array for the base cgroup files

* Rename it from files[] (really?) to cgroup_base_files[].

* Drop CGROUP_FILE_GENERIC_PREFIX which was defined as "cgroup." and
  used inconsistently.  Just use "cgroup." directly.

* Collect insane files at the end.  Note that only the insane ones are
  missing "cgroup." prefix.

This patch doesn't introduce any functional changes.

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

1 files changed, 24 insertions, 23 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b3bb8a393642..bc53d5014b28 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4029,35 +4029,16 @@ static int cgroup_clone_children_write(struct cgroup *cgrp,
         return 0;
 }
 
-/*
- * for the common functions, 'private' gives the type of file
- */
-/* for hysterical raisins, we can't put this on the older files */
-#define CGROUP_FILE_GENERIC_PREFIX "cgroup."
-static struct cftype files[] = {
+static struct cftype cgroup_base_files[] = {
         {
-                .name = "tasks",
-                .flags = CFTYPE_INSANE,         /* use "procs" instead */
-                .open = cgroup_tasks_open,
-                .write_u64 = cgroup_tasks_write,
-                .release = cgroup_pidlist_release,
-                .mode = S_IRUGO | S_IWUSR,
-        },
-        {
-                .name = CGROUP_FILE_GENERIC_PREFIX "procs",
+                .name = "cgroup.procs",
                 .open = cgroup_procs_open,
                 .write_u64 = cgroup_procs_write,
                 .release = cgroup_pidlist_release,
                 .mode = S_IRUGO | S_IWUSR,
         },
         {
-                .name = "notify_on_release",
-                .flags = CFTYPE_INSANE,
-                .read_u64 = cgroup_read_notify_on_release,
-                .write_u64 = cgroup_write_notify_on_release,
-        },
-        {
-                .name = CGROUP_FILE_GENERIC_PREFIX "event_control",
+                .name = "cgroup.event_control",
                 .write_string = cgroup_write_event_control,
                 .mode = S_IWUGO,
         },
@@ -4072,6 +4053,26 @@ static struct cftype files[] = {
                 .flags = CFTYPE_ONLY_ON_ROOT,
                 .read_seq_string = cgroup_sane_behavior_show,
         },
+
+        /*
+         * Historical crazy stuff.  These don't have "cgroup."  prefix and
+         * don't exist if sane_behavior.  If you're depending on these, be
+         * prepared to be burned.
+         */
+        {
+                .name = "tasks",
+                .flags = CFTYPE_INSANE,         /* use "procs" instead */
+                .open = cgroup_tasks_open,
+                .write_u64 = cgroup_tasks_write,
+                .release = cgroup_pidlist_release,
+                .mode = S_IRUGO | S_IWUSR,
+        },
+        {
+                .name = "notify_on_release",
+                .flags = CFTYPE_INSANE,
+                .read_u64 = cgroup_read_notify_on_release,
+                .write_u64 = cgroup_write_notify_on_release,
+        },
         {
                 .name = "release_agent",
                 .flags = CFTYPE_INSANE | CFTYPE_ONLY_ON_ROOT,
@@ -4095,7 +4096,7 @@ static int cgroup_populate_dir(struct cgroup *cgrp, bool base_files,
         struct cgroup_subsys *ss;
 
         if (base_files) {
-                err = cgroup_addrm_files(cgrp, NULL, files, true);
+                err = cgroup_addrm_files(cgrp, NULL, cgroup_base_files, true);
                 if (err < 0)
                         return err;
         }