diff options
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/hrtimer.c | 12 | ||||
-rw-r--r-- | kernel/time/posix-timers.c | 34 | ||||
-rw-r--r-- | kernel/time/tick-sched.c | 19 | ||||
-rw-r--r-- | kernel/time/timer.c | 9 |
4 files changed, 54 insertions, 20 deletions
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 17f7bcff1e02..8c4e27cbfe7f 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -312,7 +312,7 @@ EXPORT_SYMBOL_GPL(__ktime_divns); */ ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs) { - ktime_t res = ktime_add(lhs, rhs); + ktime_t res = ktime_add_unsafe(lhs, rhs); /* * We use KTIME_SEC_MAX here, the maximum timeout which we can @@ -669,7 +669,9 @@ static void hrtimer_reprogram(struct hrtimer *timer, static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { base->expires_next.tv64 = KTIME_MAX; + base->hang_detected = 0; base->hres_active = 0; + base->next_timer = NULL; } /* @@ -1137,7 +1139,12 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, cpu_base = raw_cpu_ptr(&hrtimer_bases); - if (clock_id == CLOCK_REALTIME && mode != HRTIMER_MODE_ABS) + /* + * POSIX magic: Relative CLOCK_REALTIME timers are not affected by + * clock modifications, so they needs to become CLOCK_MONOTONIC to + * ensure POSIX compliance. + */ + if (clock_id == CLOCK_REALTIME && mode & HRTIMER_MODE_REL) clock_id = CLOCK_MONOTONIC; base = hrtimer_clockid_to_base(clock_id); @@ -1615,6 +1622,7 @@ static void init_hrtimers_cpu(int cpu) timerqueue_init_head(&cpu_base->clock_base[i].active); } + cpu_base->active_bases = 0; cpu_base->cpu = cpu; hrtimer_init_hres(cpu_base); } diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index f2826c35e918..fc7c37ad90a0 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -507,17 +507,22 @@ static struct pid *good_sigevent(sigevent_t * event) { struct task_struct *rtn = current->group_leader; - if ((event->sigev_notify & SIGEV_THREAD_ID ) && - (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) || - !same_thread_group(rtn, current) || - (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL)) + switch (event->sigev_notify) { + case SIGEV_SIGNAL | SIGEV_THREAD_ID: + rtn = find_task_by_vpid(event->sigev_notify_thread_id); + if (!rtn || !same_thread_group(rtn, current)) + return NULL; + /* FALLTHRU */ + case SIGEV_SIGNAL: + case SIGEV_THREAD: + if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX) + return NULL; + /* FALLTHRU */ + case SIGEV_NONE: + return task_pid(rtn); + default: return NULL; - - if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) && - ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX))) - return NULL; - - return task_pid(rtn); + } } void posix_timers_register_clock(const clockid_t clock_id, @@ -745,8 +750,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) /* interval timer ? */ if (iv.tv64) cur_setting->it_interval = ktime_to_timespec(iv); - else if (!hrtimer_active(timer) && - (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) + else if (!hrtimer_active(timer) && timr->it_sigev_notify != SIGEV_NONE) return; now = timer->base->get_time(); @@ -757,7 +761,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) * expiry is > now. */ if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING || - (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) + timr->it_sigev_notify == SIGEV_NONE)) timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv); remaining = __hrtimer_expires_remaining_adjusted(timer, now); @@ -767,7 +771,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) * A single shot SIGEV_NONE timer must return 0, when * it is expired ! */ - if ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) + if (timr->it_sigev_notify != SIGEV_NONE) cur_setting->it_value.tv_nsec = 1; } else cur_setting->it_value = ktime_to_timespec(remaining); @@ -865,7 +869,7 @@ common_timer_set(struct k_itimer *timr, int flags, timr->it.real.interval = timespec_to_ktime(new_setting->it_interval); /* SIGEV_NONE timers are not queued ! See common_timer_get */ - if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) { + if (timr->it_sigev_notify == SIGEV_NONE) { /* Setup correct expiry time for relative timers */ if (mode == HRTIMER_MODE_REL) { hrtimer_add_expires(timer, timer->base->get_time()); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 22c57e191a23..e5d228f7224c 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -568,6 +568,11 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now) tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1); } +static inline bool local_timer_softirq_pending(void) +{ + return local_softirq_pending() & TIMER_SOFTIRQ; +} + static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts, ktime_t now, int cpu) { @@ -584,8 +589,18 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts, } while (read_seqretry(&jiffies_lock, seq)); ts->last_jiffies = basejiff; - if (rcu_needs_cpu(basemono, &next_rcu) || - arch_needs_cpu() || irq_work_needs_cpu()) { + /* + * Keep the periodic tick, when RCU, architecture or irq_work + * requests it. + * Aside of that check whether the local timer softirq is + * pending. If so its a bad idea to call get_next_timer_interrupt() + * because there is an already expired timer, so it will request + * immeditate expiry, which rearms the hardware timer with a + * minimal delta which brings us back to this place + * immediately. Lather, rinse and repeat... + */ + if (rcu_needs_cpu(basemono, &next_rcu) || arch_needs_cpu() || + irq_work_needs_cpu() || local_timer_softirq_pending()) { next_tick = basemono + TICK_NSEC; } else { /* diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 125407144c01..3d7588a2e97c 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -764,8 +764,15 @@ static struct tvec_base *lock_timer_base(struct timer_list *timer, __acquires(timer->base->lock) { for (;;) { - u32 tf = timer->flags; struct tvec_base *base; + u32 tf; + + /* + * We need to use READ_ONCE() here, otherwise the compiler + * might re-read @tf between the check for TIMER_MIGRATING + * and spin_lock(). + */ + tf = READ_ONCE(timer->flags); if (!(tf & TIMER_MIGRATING)) { base = per_cpu_ptr(&tvec_bases, tf & TIMER_CPUMASK); |