[PATCH] nohz: Fix local_timer_softirq_pending()

From: Anna-Maria Gleixner
Date: Tue Jul 31 2018 - 12:14:45 EST


local_timer_softirq_pending() checks whether the timer softirq is
pending with: local_softirq_pending() & TIMER_SOFTIRQ.

This is wrong because TIMER_SOFTIRQ is the softirq number and not a
bitmask. So the test checks for the wrong bit.

Use BIT(TIMER_SOFTIRQ) instead.

Fixes: 5d62c183f9e9 ("nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()")
Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>
---
kernel/time/tick-sched.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index da9455a6b42b..5b33e2f5c0ed 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -642,7 +642,7 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)

static inline bool local_timer_softirq_pending(void)
{
- return local_softirq_pending() & TIMER_SOFTIRQ;
+ return local_softirq_pending() & BIT(TIMER_SOFTIRQ);
}

static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)
--
2.18.0