cgroup: simplify proc_cgroup_show()

Use the ONE macro instead of REG, and we can simplify proc_cgroup_show().

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

1 files changed, 2 insertions, 17 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index baf852b648ad..6b96892015ec 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -376,21 +376,6 @@ static const struct file_operations proc_lstats_operations = {
 
 #endif
 
-#ifdef CONFIG_CGROUPS
-static int cgroup_open(struct inode *inode, struct file *file)
-{
-        struct pid *pid = PROC_I(inode)->pid;
-        return single_open(file, proc_cgroup_show, pid);
-}
-
-static const struct file_operations proc_cgroup_operations = {
-        .open           = cgroup_open,
-        .read           = seq_read,
-        .llseek         = seq_lseek,
-        .release        = single_release,
-};
-#endif
-
 #ifdef CONFIG_PROC_PID_CPUSET
 
 static int cpuset_open(struct inode *inode, struct file *file)
@@ -2576,7 +2561,7 @@ static const struct pid_entry tgid_base_stuff[] = {
         REG("cpuset",     S_IRUGO, proc_cpuset_operations),
 #endif
 #ifdef CONFIG_CGROUPS
-        REG("cgroup",  S_IRUGO, proc_cgroup_operations),
+        ONE("cgroup",  S_IRUGO, proc_cgroup_show),
 #endif
         ONE("oom_score",  S_IRUGO, proc_oom_score),
         REG("oom_adj",    S_IRUGO|S_IWUSR, proc_oom_adj_operations),
@@ -2922,7 +2907,7 @@ static const struct pid_entry tid_base_stuff[] = {
         REG("cpuset",    S_IRUGO, proc_cpuset_operations),
 #endif
 #ifdef CONFIG_CGROUPS
-        REG("cgroup",  S_IRUGO, proc_cgroup_operations),
+        ONE("cgroup",  S_IRUGO, proc_cgroup_show),
 #endif
         ONE("oom_score", S_IRUGO, proc_oom_score),
         REG("oom_adj",   S_IRUGO|S_IWUSR, proc_oom_adj_operations),