nohz: Fix one jiffy count too far in idle cputime

[~andy/linux] / kernel / time / tick-sched.c

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 024540f97f74c3e94205826f33d3968ea765f626..a40260885265707603d72dee9df79f030e973221 100644 (file)
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -372,7 +372,7 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
                 * the scheduler tick in nohz_restart_sched_tick.
                 */
                if (!ts->tick_stopped) {
-                       select_nohz_load_balancer(1);
+                       nohz_balance_enter_idle(cpu);
                        calc_load_enter_idle();
 
                        ts->last_tick = hrtimer_get_expires(&ts->sched_timer);
@@ -436,7 +436,8 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
        if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
                static int ratelimit;
 
-               if (ratelimit < 10) {
+               if (ratelimit < 10 &&
+                   (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
                        printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
                               (unsigned int) local_softirq_pending());
                        ratelimit++;
@@ -569,10 +570,10 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
 static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now)
 {
        /* Update jiffies first */
-       select_nohz_load_balancer(0);
        tick_do_update_jiffies64(now);
        update_cpu_load_nohz();
 
+       calc_load_exit_idle();
        touch_softlockup_watchdog();
        /*
         * Cancel the scheduled timer and restore the tick
@@ -834,7 +835,7 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer)
                 */
                if (ts->tick_stopped) {
                        touch_softlockup_watchdog();
-                       if (idle_cpu(cpu))
+                       if (is_idle_task(current))
                                ts->idle_jiffies++;
                }
                update_process_times(user_mode(regs));