[BUGFIX PATCH 3/2] posix-cpu-timers: check_thread_timers() uses task_sched_runtime()

[KOSAKI Motohiro <kosaki.motohiro@gmail.com>]

A type of tsk->se.sum_exec_runtime is u64. Thus reading it is racy when
running 32bit. We should use task_sched_runtime().

Cc: Olivier Langlois <olivier@trillion01.com>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
---
 kernel/posix-cpu-timers.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index dc61bc3..651b6c7 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -944,7 +944,8 @@ static void check_thread_timers(struct task_struct *tsk,
 		struct cpu_timer_list *t = list_first_entry(timers,
 						      struct cpu_timer_list,
 						      entry);
-		if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) {
+		unsigned long long runtime = task_sched_runtime(tsk, false);
+		if (!--maxfire || runtime < t->expires.sched) {
 			tsk->cputime_expires.sched_exp = t->expires.sched;
 			break;
 		}
-- 
1.7.1