diff options
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/hrtimer.c | 2 | ||||
-rw-r--r-- | kernel/time/tick-common.c | 42 |
2 files changed, 16 insertions, 28 deletions
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 492c14aac642..b8ee320208d4 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1285,6 +1285,8 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, struct hrtimer_clock_base *base; unsigned long flags; + if (WARN_ON_ONCE(!timer->function)) + return; /* * Check whether the HRTIMER_MODE_SOFT bit and hrtimer.is_soft * match on CONFIG_PREEMPT_RT = n. With PREEMPT_RT check the hard diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index d88b13076b79..a47bcf71defc 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -178,26 +178,6 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast) } } -#ifdef CONFIG_NO_HZ_FULL -static void giveup_do_timer(void *info) -{ - int cpu = *(unsigned int *)info; - - WARN_ON(tick_do_timer_cpu != smp_processor_id()); - - tick_do_timer_cpu = cpu; -} - -static void tick_take_do_timer_from_boot(void) -{ - int cpu = smp_processor_id(); - int from = tick_do_timer_boot_cpu; - - if (from >= 0 && from != cpu) - smp_call_function_single(from, giveup_do_timer, &cpu, 1); -} -#endif - /* * Setup the tick device */ @@ -221,19 +201,25 @@ static void tick_setup_device(struct tick_device *td, tick_next_period = ktime_get(); #ifdef CONFIG_NO_HZ_FULL /* - * The boot CPU may be nohz_full, in which case set - * tick_do_timer_boot_cpu so the first housekeeping - * secondary that comes up will take do_timer from - * us. + * The boot CPU may be nohz_full, in which case the + * first housekeeping secondary will take do_timer() + * from it. */ if (tick_nohz_full_cpu(cpu)) tick_do_timer_boot_cpu = cpu; - } else if (tick_do_timer_boot_cpu != -1 && - !tick_nohz_full_cpu(cpu)) { - tick_take_do_timer_from_boot(); + } else if (tick_do_timer_boot_cpu != -1 && !tick_nohz_full_cpu(cpu)) { tick_do_timer_boot_cpu = -1; - WARN_ON(READ_ONCE(tick_do_timer_cpu) != cpu); + /* + * The boot CPU will stay in periodic (NOHZ disabled) + * mode until clocksource_done_booting() called after + * smp_init() selects a high resolution clocksource and + * timekeeping_notify() kicks the NOHZ stuff alive. + * + * So this WRITE_ONCE can only race with the READ_ONCE + * check in tick_periodic() but this race is harmless. + */ + WRITE_ONCE(tick_do_timer_cpu, cpu); #endif } |