diff options
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/clocksource.c | 40 | ||||
| -rw-r--r-- | kernel/time/itimer.c | 5 | ||||
| -rw-r--r-- | kernel/time/posix-cpu-timers.c | 2 | ||||
| -rw-r--r-- | kernel/time/posix-timers.c | 34 |
4 files changed, 45 insertions, 36 deletions
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index f74fb00d8064..0e6e97a01942 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -133,19 +133,40 @@ static void inline clocksource_watchdog_unlock(unsigned long *flags) spin_unlock_irqrestore(&watchdog_lock, *flags); } +static int clocksource_watchdog_kthread(void *data); +static void __clocksource_change_rating(struct clocksource *cs, int rating); + /* * Interval: 0.5sec Threshold: 0.0625s */ #define WATCHDOG_INTERVAL (HZ >> 1) #define WATCHDOG_THRESHOLD (NSEC_PER_SEC >> 4) +static void clocksource_watchdog_work(struct work_struct *work) +{ + /* + * We cannot directly run clocksource_watchdog_kthread() here, because + * clocksource_select() calls timekeeping_notify() which uses + * stop_machine(). One cannot use stop_machine() from a workqueue() due + * lock inversions wrt CPU hotplug. + * + * Also, we only ever run this work once or twice during the lifetime + * of the kernel, so there is no point in creating a more permanent + * kthread for this. + * + * If kthread_run fails the next watchdog scan over the + * watchdog_list will find the unstable clock again. + */ + kthread_run(clocksource_watchdog_kthread, NULL, "kwatchdog"); +} + static void __clocksource_unstable(struct clocksource *cs) { cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG); cs->flags |= CLOCK_SOURCE_UNSTABLE; /* - * If the clocksource is registered clocksource_watchdog_work() will + * If the clocksource is registered clocksource_watchdog_kthread() will * re-rate and re-select. */ if (list_empty(&cs->list)) { @@ -156,7 +177,7 @@ static void __clocksource_unstable(struct clocksource *cs) if (cs->mark_unstable) cs->mark_unstable(cs); - /* kick clocksource_watchdog_work() */ + /* kick clocksource_watchdog_kthread() */ if (finished_booting) schedule_work(&watchdog_work); } @@ -166,7 +187,7 @@ static void __clocksource_unstable(struct clocksource *cs) * @cs: clocksource to be marked unstable * * This function is called by the x86 TSC code to mark clocksources as unstable; - * it defers demotion and re-selection to a work. + * it defers demotion and re-selection to a kthread. */ void clocksource_mark_unstable(struct clocksource *cs) { @@ -391,9 +412,7 @@ static void clocksource_dequeue_watchdog(struct clocksource *cs) } } -static void __clocksource_change_rating(struct clocksource *cs, int rating); - -static int __clocksource_watchdog_work(void) +static int __clocksource_watchdog_kthread(void) { struct clocksource *cs, *tmp; unsigned long flags; @@ -418,12 +437,13 @@ static int __clocksource_watchdog_work(void) return select; } -static void clocksource_watchdog_work(struct work_struct *work) +static int clocksource_watchdog_kthread(void *data) { mutex_lock(&clocksource_mutex); - if (__clocksource_watchdog_work()) + if (__clocksource_watchdog_kthread()) clocksource_select(); mutex_unlock(&clocksource_mutex); + return 0; } static bool clocksource_is_watchdog(struct clocksource *cs) @@ -442,7 +462,7 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs) static void clocksource_select_watchdog(bool fallback) { } static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { } static inline void clocksource_resume_watchdog(void) { } -static inline int __clocksource_watchdog_work(void) { return 0; } +static inline int __clocksource_watchdog_kthread(void) { return 0; } static bool clocksource_is_watchdog(struct clocksource *cs) { return false; } void clocksource_mark_unstable(struct clocksource *cs) { } @@ -810,7 +830,7 @@ static int __init clocksource_done_booting(void) /* * Run the watchdog first to eliminate unstable clock sources */ - __clocksource_watchdog_work(); + __clocksource_watchdog_kthread(); clocksource_select(); mutex_unlock(&clocksource_mutex); return 0; diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c index f26acef5d7b4..9a65713c8309 100644 --- a/kernel/time/itimer.c +++ b/kernel/time/itimer.c @@ -139,9 +139,10 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer) { struct signal_struct *sig = container_of(timer, struct signal_struct, real_timer); + struct pid *leader_pid = sig->pids[PIDTYPE_TGID]; - trace_itimer_expire(ITIMER_REAL, sig->leader_pid, 0); - kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid); + trace_itimer_expire(ITIMER_REAL, leader_pid, 0); + kill_pid_info(SIGALRM, SEND_SIG_PRIV, leader_pid); return HRTIMER_NORESTART; } diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 294d7b65af33..ce32cf741b25 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -894,7 +894,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, trace_itimer_expire(signo == SIGPROF ? ITIMER_PROF : ITIMER_VIRTUAL, - tsk->signal->leader_pid, cur_time); + task_tgid(tsk), cur_time); __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); } diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 3ac7295306dc..4b9127e95430 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -86,15 +86,6 @@ static const struct k_clock clock_realtime, clock_monotonic; #endif /* - * parisc wants ENOTSUP instead of EOPNOTSUPP - */ -#ifndef ENOTSUP -# define ENANOSLEEP_NOTSUP EOPNOTSUPP -#else -# define ENANOSLEEP_NOTSUP ENOTSUP -#endif - -/* * The timer ID is turned into a timer address by idr_find(). * Verifying a valid ID consists of: * @@ -342,8 +333,8 @@ void posixtimer_rearm(struct siginfo *info) int posix_timer_event(struct k_itimer *timr, int si_private) { - struct task_struct *task; - int shared, ret = -1; + enum pid_type type; + int ret = -1; /* * FIXME: if ->sigq is queued we can race with * dequeue_signal()->posixtimer_rearm(). @@ -357,13 +348,8 @@ int posix_timer_event(struct k_itimer *timr, int si_private) */ timr->sigq->info.si_sys_private = si_private; - rcu_read_lock(); - task = pid_task(timr->it_pid, PIDTYPE_PID); - if (task) { - shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID); - ret = send_sigqueue(timr->sigq, task, shared); - } - rcu_read_unlock(); + type = !(timr->it_sigev_notify & SIGEV_THREAD_ID) ? PIDTYPE_TGID : PIDTYPE_PID; + ret = send_sigqueue(timr->sigq, timr->it_pid, type); /* If we failed to send the signal the timer stops. */ return ret > 0; } @@ -442,11 +428,13 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer) static struct pid *good_sigevent(sigevent_t * event) { - struct task_struct *rtn = current->group_leader; + struct pid *pid = task_tgid(current); + struct task_struct *rtn; switch (event->sigev_notify) { case SIGEV_SIGNAL | SIGEV_THREAD_ID: - rtn = find_task_by_vpid(event->sigev_notify_thread_id); + pid = find_vpid(event->sigev_notify_thread_id); + rtn = pid_task(pid, PIDTYPE_PID); if (!rtn || !same_thread_group(rtn, current)) return NULL; /* FALLTHRU */ @@ -456,7 +444,7 @@ static struct pid *good_sigevent(sigevent_t * event) return NULL; /* FALLTHRU */ case SIGEV_NONE: - return task_pid(rtn); + return pid; default: return NULL; } @@ -1231,7 +1219,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, if (!kc) return -EINVAL; if (!kc->nsleep) - return -ENANOSLEEP_NOTSUP; + return -EOPNOTSUPP; if (get_timespec64(&t, rqtp)) return -EFAULT; @@ -1258,7 +1246,7 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags, if (!kc) return -EINVAL; if (!kc->nsleep) - return -ENANOSLEEP_NOTSUP; + return -EOPNOTSUPP; if (compat_get_timespec64(&t, rqtp)) return -EFAULT; |
