sched/debug: Replace vruntime with wait_sum in /proc/sched_debug

Within runnable tasks in /proc/sched_debug, vruntime is printed twice,
once as tree-key and again as exec-runtime.

Since exec-runtime isnt populated in !CONFIG_SCHEDSTATS, use this field
to print wait_sum.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1433751041-11724-3-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/sched/debug.c

@@ -132,7 +132,7 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
 		p->prio);
 #ifdef CONFIG_SCHEDSTATS
 	SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
-		SPLIT_NS(p->se.vruntime),
+		SPLIT_NS(p->se.statistics.wait_sum),
 		SPLIT_NS(p->se.sum_exec_runtime),
 		SPLIT_NS(p->se.statistics.sum_sleep_runtime));
 #else
@@ -158,7 +158,7 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
 	SEQ_printf(m,
 	"\nrunnable tasks:\n"
 	"            task   PID         tree-key  switches  prio"
-	"     exec-runtime         sum-exec        sum-sleep\n"
+	"     wait-time             sum-exec        sum-sleep\n"
 	"------------------------------------------------------"
 	"----------------------------------------------------\n");