sched: Get group names back in /proc/sched_debug

@@ -16,6 +16,9 @@
 #include <linux/kallsyms.h>
 #include <linux/utsname.h>
 
+static char group_path[PATH_MAX];
+static DEFINE_SPINLOCK(sched_debug_lock);
+
 /*
  * This allows printing both to /proc/sched_debug and
  * to the console

@@ -86,6 +89,23 @@ static void print_cfs_group_stats(struct
 }
 #endif
 
+#ifdef CONFIG_CGROUP_SCHED
+static char * task_group_path(struct task_group *tg)
+{
+	/*
+	 * May be NULL if the underlying cgroup isn't fully-created yet
+	 */
+	if (!tg->css.cgroup) {
+		group_path[0] = '\0';
+		return group_path;
+	}
+	rcu_read_lock();
+	cgroup_path(tg->css.cgroup, group_path, PATH_MAX);
+	rcu_read_unlock();
+	return group_path;
+}
+#endif
+
 static void
 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
 {

@@ -108,6 +128,9 @@ print_task(struct seq_file *m, struct rq
 	SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
 		0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
 #endif
+#ifdef CONFIG_CGROUP_SCHED
+	SEQ_printf(m, " %s", task_group_path(task_group(p)));
+#endif
 
 	SEQ_printf(m, "\n");
 }

@@ -144,7 +167,11 @@ void print_cfs_rq(struct seq_file *m, in
 	struct sched_entity *last;
 	unsigned long flags;
 
+#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
+	SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, task_group_path(cfs_rq->tg));
+#else
 	SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
+#endif
 	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
 			SPLIT_NS(cfs_rq->exec_clock));
 

@@ -191,7 +218,11 @@ void print_cfs_rq(struct seq_file *m, in
 
 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 {
+#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
+	SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, task_group_path(rt_rq->tg));
+#else
 	SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
+#endif
 
 #define P(x) \
 	SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))

@@ -212,6 +243,7 @@ extern __read_mostly int sched_clock_run
 static void print_cpu(struct seq_file *m, int cpu)
 {
 	struct rq *rq = cpu_rq(cpu);
+	unsigned long flags;
 
 #ifdef CONFIG_X86
 	{

@@ -266,10 +298,12 @@ static void print_cpu(struct seq_file *m
 
 #undef P
 #endif
+	spin_lock_irqsave(&sched_debug_lock, flags);
 	print_cfs_stats(m, cpu);
 	print_rt_stats(m, cpu);
 
 	print_rq(m, rq, cpu);
+	spin_unlock_irqrestore(&sched_debug_lock, flags);
 }
 
 static const char *sched_tunable_scaling_names[] = {

@@ -92,6 +92,14 @@ static void print_cfs_group_stats(struct
 #ifdef CONFIG_CGROUP_SCHED
 static char * task_group_path(struct task_group *tg)
 {
+#ifdef CONFIG_SCHED_AUTOGROUP
+	int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled);
+
+	if (enabled && tg->autogroup) {
+		autogroup_path(tg, group_path, PATH_MAX);
+		return group_path;
+	}
+#endif
 	/*
 	 * May be NULL if the underlying cgroup isn't fully-created yet
 	 */