cpuset: use cgroup_name() in cpuset_print_task_mems_allowed()

Use cgroup_name() instead of cgrp->dentry->name. This makes the code
a bit simpler.

While at it, remove cpuset_name and make cpuset_nodelist a local variable
to cpuset_print_task_mems_allowed().

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

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 4f9dfe43ecbd777d7bf03bed72c5da566e952b62..ace5bfcdcb301d250fb122713b1de5f9404d8d42 100644 (file)
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -264,17 +264,6 @@ static struct cpuset top_cpuset = {
 static DEFINE_MUTEX(cpuset_mutex);
 static DEFINE_MUTEX(callback_mutex);
 
-/*
- * cpuset_buffer_lock protects both the cpuset_name and cpuset_nodelist
- * buffers.  They are statically allocated to prevent using excess stack
- * when calling cpuset_print_task_mems_allowed().
- */
-#define CPUSET_NAME_LEN                (128)
-#define        CPUSET_NODELIST_LEN     (256)
-static char cpuset_name[CPUSET_NAME_LEN];
-static char cpuset_nodelist[CPUSET_NODELIST_LEN];
-static DEFINE_SPINLOCK(cpuset_buffer_lock);
-
 /*
  * CPU / memory hotplug is handled asynchronously.
  */
@@ -2592,6 +2581,8 @@ int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
        return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed);
 }
 
+#define CPUSET_NODELIST_LEN    (256)
+
 /**
  * cpuset_print_task_mems_allowed - prints task's cpuset and mems_allowed
  * @task: pointer to task_struct of some task.
@@ -2602,24 +2593,19 @@ int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
  */
 void cpuset_print_task_mems_allowed(struct task_struct *tsk)
 {
-       struct dentry *dentry;
+        /* Statically allocated to prevent using excess stack. */
+       static char cpuset_nodelist[CPUSET_NODELIST_LEN];
+       static DEFINE_SPINLOCK(cpuset_buffer_lock);
 
-       dentry = task_cs(tsk)->css.cgroup->dentry;
-       spin_lock(&cpuset_buffer_lock);
+       struct cgroup *cgrp = task_cs(tsk)->css.cgroup;
 
-       if (!dentry) {
-               strcpy(cpuset_name, "/");
-       } else {
-               spin_lock(&dentry->d_lock);
-               strlcpy(cpuset_name, (const char *)dentry->d_name.name,
-                       CPUSET_NAME_LEN);
-               spin_unlock(&dentry->d_lock);
-       }
+       spin_lock(&cpuset_buffer_lock);
 
        nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN,
                           tsk->mems_allowed);
        printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n",
-              tsk->comm, cpuset_name, cpuset_nodelist);
+              tsk->comm, cgroup_name(cgrp), cpuset_nodelist);
+
        spin_unlock(&cpuset_buffer_lock);
 }