From 3c4fbe5e01d7e5309be5045e7ae0db20a049e6dc Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Wed, 20 Aug 2008 16:37:38 -0700 Subject: [PATCH] nohz: fix wrong event handler after online an offlined cpu On the tickless system(CONFIG_NO_HZ=y and CONFIG_HIGH_RES_TIMERS=n), after I made an offlined cpu online, I found this cpu's event handler was tick_handle_periodic, not tick_nohz_handler. After debuging, I found this bug was caused by the wrong tick mode. the tick mode is not changed to NOHZ_MODE_INACTIVE when the cpu is offline. This patch fixes this bug. Signed-off-by: Miao Xie Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar --- include/linux/tick.h | 5 ++++- kernel/time/tick-sched.c | 6 +++++- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/include/linux/tick.h b/include/linux/tick.h index d3c02695dc5d..8cf8cfe2cc97 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -74,10 +74,13 @@ extern struct tick_device *tick_get_device(int cpu); extern int tick_init_highres(void); extern int tick_program_event(ktime_t expires, int force); extern void tick_setup_sched_timer(void); +# endif + +# if defined CONFIG_NO_HZ || defined CONFIG_HIGH_RES_TIMERS extern void tick_cancel_sched_timer(int cpu); # else static inline void tick_cancel_sched_timer(int cpu) { } -# endif /* HIGHRES */ +# endif # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST extern struct tick_device *tick_get_broadcast_device(void); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index f5da526424a9..7a46bde78c66 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -643,17 +643,21 @@ void tick_setup_sched_timer(void) ts->nohz_mode = NOHZ_MODE_HIGHRES; #endif } +#endif /* HIGH_RES_TIMERS */ +#if defined CONFIG_NO_HZ || defined CONFIG_HIGH_RES_TIMERS void tick_cancel_sched_timer(int cpu) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); +# ifdef CONFIG_HIGH_RES_TIMERS if (ts->sched_timer.base) hrtimer_cancel(&ts->sched_timer); +# endif ts->nohz_mode = NOHZ_MODE_INACTIVE; } -#endif /* HIGH_RES_TIMERS */ +#endif /** * Async notification about clocksource changes -- 2.20.1