sched/cpuacct: Clean up cpuacct.h

Now most of the code in cpuacct.h can be moved to cpuacct.c

Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/515536D5.2080401@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 071ae8d..9305fd2 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -16,7 +16,49 @@
  * (balbir@in.ibm.com).
  */
 
-struct cpuacct root_cpuacct;
+/* Time spent by the tasks of the cpu accounting group executing in ... */
+enum cpuacct_stat_index {
+	CPUACCT_STAT_USER,	/* ... user mode */
+	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */
+
+	CPUACCT_STAT_NSTATS,
+};
+
+/* track cpu usage of a group of tasks and its child groups */
+struct cpuacct {
+	struct cgroup_subsys_state css;
+	/* cpuusage holds pointer to a u64-type object on every cpu */
+	u64 __percpu *cpuusage;
+	struct kernel_cpustat __percpu *cpustat;
+};
+
+/* return cpu accounting group corresponding to this container */
+static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp)
+{
+	return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id),
+			    struct cpuacct, css);
+}
+
+/* return cpu accounting group to which this task belongs */
+static inline struct cpuacct *task_ca(struct task_struct *tsk)
+{
+	return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
+			    struct cpuacct, css);
+}
+
+static inline struct cpuacct *__parent_ca(struct cpuacct *ca)
+{
+	return cgroup_ca(ca->css.cgroup->parent);
+}
+
+static inline struct cpuacct *parent_ca(struct cpuacct *ca)
+{
+	if (!ca->css.cgroup->parent)
+		return NULL;
+	return cgroup_ca(ca->css.cgroup->parent);
+}
+
+static struct cpuacct root_cpuacct;
 
 /* create a new cpu accounting group */
 static struct cgroup_subsys_state *cpuacct_css_alloc(struct cgroup *cgrp)