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>

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b3bb8a3..bc53d50 100644 (file)
--- 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;
        }