From becf8b5d00f4b47e847f98322cdaf8cd16243861 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 9 Jan 2006 20:52:38 -0800 Subject: [PATCH] hrtimer: convert posix timers completely - convert posix-timers.c to use hrtimers - remove the now obsolete abslist code Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/posix-timers.c | 717 ++++++++++---------------------------------------- 1 file changed, 135 insertions(+), 582 deletions(-) (limited to 'kernel/posix-timers.c') diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index ba900587b815..9e66e614862a 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -35,7 +35,6 @@ #include #include #include -#include #include #include @@ -49,12 +48,6 @@ #include #include -#define CLOCK_REALTIME_RES TICK_NSEC /* In nano seconds. */ - -static inline u64 mpy_l_X_l_ll(unsigned long mpy1,unsigned long mpy2) -{ - return (u64)mpy1 * mpy2; -} /* * Management arrays for POSIX timers. Timers are kept in slab memory * Timer ids are allocated by an external routine that keeps track of the @@ -140,18 +133,18 @@ static DEFINE_SPINLOCK(idr_lock); */ static struct k_clock posix_clocks[MAX_CLOCKS]; + /* - * We only have one real clock that can be set so we need only one abs list, - * even if we should want to have several clocks with differing resolutions. + * These ones are defined below. */ -static struct k_clock_abs abs_list = {.list = LIST_HEAD_INIT(abs_list.list), - .lock = SPIN_LOCK_UNLOCKED}; +static int common_nsleep(const clockid_t, int flags, struct timespec *t, + struct timespec __user *rmtp); +static void common_timer_get(struct k_itimer *, struct itimerspec *); +static int common_timer_set(struct k_itimer *, int, + struct itimerspec *, struct itimerspec *); +static int common_timer_del(struct k_itimer *timer); -static void posix_timer_fn(unsigned long); -static u64 do_posix_clock_monotonic_gettime_parts( - struct timespec *tp, struct timespec *mo); -int do_posix_clock_monotonic_gettime(struct timespec *tp); -static int do_posix_clock_monotonic_get(const clockid_t, struct timespec *tp); +static int posix_timer_fn(void *data); static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags); @@ -184,10 +177,12 @@ static inline int common_clock_getres(const clockid_t which_clock, return 0; } -static inline int common_clock_get(const clockid_t which_clock, - struct timespec *tp) +/* + * Get real time for posix timers + */ +static int common_clock_get(clockid_t which_clock, struct timespec *tp) { - getnstimeofday(tp); + ktime_get_real_ts(tp); return 0; } @@ -199,25 +194,14 @@ static inline int common_clock_set(const clockid_t which_clock, static inline int common_timer_create(struct k_itimer *new_timer) { - INIT_LIST_HEAD(&new_timer->it.real.abs_timer_entry); - init_timer(&new_timer->it.real.timer); - new_timer->it.real.timer.data = (unsigned long) new_timer; + hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock); + new_timer->it.real.timer.data = new_timer; new_timer->it.real.timer.function = posix_timer_fn; return 0; } /* - * These ones are defined below. - */ -static int common_nsleep(const clockid_t, int flags, struct timespec *t, - struct timespec __user *rmtp); -static void common_timer_get(struct k_itimer *, struct itimerspec *); -static int common_timer_set(struct k_itimer *, int, - struct itimerspec *, struct itimerspec *); -static int common_timer_del(struct k_itimer *timer); - -/* - * Return nonzero iff we know a priori this clockid_t value is bogus. + * Return nonzero if we know a priori this clockid_t value is bogus. */ static inline int invalid_clockid(const clockid_t which_clock) { @@ -227,26 +211,32 @@ static inline int invalid_clockid(const clockid_t which_clock) return 1; if (posix_clocks[which_clock].clock_getres != NULL) return 0; -#ifndef CLOCK_DISPATCH_DIRECT if (posix_clocks[which_clock].res != 0) return 0; -#endif return 1; } +/* + * Get monotonic time for posix timers + */ +static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp) +{ + ktime_get_ts(tp); + return 0; +} /* * Initialize everything, well, just everything in Posix clocks/timers ;) */ static __init int init_posix_timers(void) { - struct k_clock clock_realtime = {.res = CLOCK_REALTIME_RES, - .abs_struct = &abs_list + struct k_clock clock_realtime = { + .clock_getres = hrtimer_get_res, }; - struct k_clock clock_monotonic = {.res = CLOCK_REALTIME_RES, - .abs_struct = NULL, - .clock_get = do_posix_clock_monotonic_get, - .clock_set = do_posix_clock_nosettime + struct k_clock clock_monotonic = { + .clock_getres = hrtimer_get_res, + .clock_get = posix_ktime_get_ts, + .clock_set = do_posix_clock_nosettime, }; register_posix_clock(CLOCK_REALTIME, &clock_realtime); @@ -260,117 +250,17 @@ static __init int init_posix_timers(void) __initcall(init_posix_timers); -static void tstojiffie(struct timespec *tp, int res, u64 *jiff) -{ - long sec = tp->tv_sec; - long nsec = tp->tv_nsec + res - 1; - - if (nsec >= NSEC_PER_SEC) { - sec++; - nsec -= NSEC_PER_SEC; - } - - /* - * The scaling constants are defined in - * The difference between there and here is that we do the - * res rounding and compute a 64-bit result (well so does that - * but it then throws away the high bits). - */ - *jiff = (mpy_l_X_l_ll(sec, SEC_CONVERSION) + - (mpy_l_X_l_ll(nsec, NSEC_CONVERSION) >> - (NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC; -} - -/* - * This function adjusts the timer as needed as a result of the clock - * being set. It should only be called for absolute timers, and then - * under the abs_list lock. It computes the time difference and sets - * the new jiffies value in the timer. It also updates the timers - * reference wall_to_monotonic value. It is complicated by the fact - * that tstojiffies() only handles positive times and it needs to work - * with both positive and negative times. Also, for negative offsets, - * we need to defeat the res round up. - * - * Return is true if there is a new time, else false. - */ -static long add_clockset_delta(struct k_itimer *timr, - struct timespec *new_wall_to) -{ - struct timespec delta; - int sign = 0; - u64 exp; - - set_normalized_timespec(&delta, - new_wall_to->tv_sec - - timr->it.real.wall_to_prev.tv_sec, - new_wall_to->tv_nsec - - timr->it.real.wall_to_prev.tv_nsec); - if (likely(!(delta.tv_sec | delta.tv_nsec))) - return 0; - if (delta.tv_sec < 0) { - set_normalized_timespec(&delta, - -delta.tv_sec, - 1 - delta.tv_nsec - - posix_clocks[timr->it_clock].res); - sign++; - } - tstojiffie(&delta, posix_clocks[timr->it_clock].res, &exp); - timr->it.real.wall_to_prev = *new_wall_to; - timr->it.real.timer.expires += (sign ? -exp : exp); - return 1; -} - -static void remove_from_abslist(struct k_itimer *timr) -{ - if (!list_empty(&timr->it.real.abs_timer_entry)) { - spin_lock(&abs_list.lock); - list_del_init(&timr->it.real.abs_timer_entry); - spin_unlock(&abs_list.lock); - } -} - static void schedule_next_timer(struct k_itimer *timr) { - struct timespec new_wall_to; - struct now_struct now; - unsigned long seq; - - /* - * Set up the timer for the next interval (if there is one). - * Note: this code uses the abs_timer_lock to protect - * it.real.wall_to_prev and must hold it until exp is set, not exactly - * obvious... - - * This function is used for CLOCK_REALTIME* and - * CLOCK_MONOTONIC* timers. If we ever want to handle other - * CLOCKs, the calling code (do_schedule_next_timer) would need - * to pull the "clock" info from the timer and dispatch the - * "other" CLOCKs "next timer" code (which, I suppose should - * also be added to the k_clock structure). - */ - if (!timr->it.real.incr) + if (timr->it.real.interval.tv64 == 0) return; - do { - seq = read_seqbegin(&xtime_lock); - new_wall_to = wall_to_monotonic; - posix_get_now(&now); - } while (read_seqretry(&xtime_lock, seq)); - - if (!list_empty(&timr->it.real.abs_timer_entry)) { - spin_lock(&abs_list.lock); - add_clockset_delta(timr, &new_wall_to); - - posix_bump_timer(timr, now); - - spin_unlock(&abs_list.lock); - } else { - posix_bump_timer(timr, now); - } + timr->it_overrun += hrtimer_forward(&timr->it.real.timer, + timr->it.real.interval); timr->it_overrun_last = timr->it_overrun; timr->it_overrun = -1; ++timr->it_requeue_pending; - add_timer(&timr->it.real.timer); + hrtimer_restart(&timr->it.real.timer); } /* @@ -391,31 +281,23 @@ void do_schedule_next_timer(struct siginfo *info) timr = lock_timer(info->si_tid, &flags); - if (!timr || timr->it_requeue_pending != info->si_sys_private) - goto exit; + if (timr && timr->it_requeue_pending == info->si_sys_private) { + if (timr->it_clock < 0) + posix_cpu_timer_schedule(timr); + else + schedule_next_timer(timr); - if (timr->it_clock < 0) /* CPU clock */ - posix_cpu_timer_schedule(timr); - else - schedule_next_timer(timr); - info->si_overrun = timr->it_overrun_last; -exit: - if (timr) - unlock_timer(timr, flags); + info->si_overrun = timr->it_overrun_last; + } + + unlock_timer(timr, flags); } int posix_timer_event(struct k_itimer *timr,int si_private) { memset(&timr->sigq->info, 0, sizeof(siginfo_t)); timr->sigq->info.si_sys_private = si_private; - /* - * Send signal to the process that owns this timer. - - * This code assumes that all the possible abs_lists share the - * same lock (there is only one list at this time). If this is - * not the case, the CLOCK info would need to be used to find - * the proper abs list lock. - */ + /* Send signal to the process that owns this timer.*/ timr->sigq->info.si_signo = timr->it_sigev_signo; timr->sigq->info.si_errno = 0; @@ -449,64 +331,35 @@ EXPORT_SYMBOL_GPL(posix_timer_event); * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers. */ -static void posix_timer_fn(unsigned long __data) +static int posix_timer_fn(void *data) { - struct k_itimer *timr = (struct k_itimer *) __data; + struct k_itimer *timr = data; unsigned long flags; - unsigned long seq; - struct timespec delta, new_wall_to; - u64 exp = 0; - int do_notify = 1; + int si_private = 0; + int ret = HRTIMER_NORESTART; spin_lock_irqsave(&timr->it_lock, flags); - if (!list_empty(&timr->it.real.abs_timer_entry)) { - spin_lock(&abs_list.lock); - do { - seq = read_seqbegin(&xtime_lock); - new_wall_to = wall_to_monotonic; - } while (read_seqretry(&xtime_lock, seq)); - set_normalized_timespec(&delta, - new_wall_to.tv_sec - - timr->it.real.wall_to_prev.tv_sec, - new_wall_to.tv_nsec - - timr->it.real.wall_to_prev.tv_nsec); - if (likely((delta.tv_sec | delta.tv_nsec ) == 0)) { - /* do nothing, timer is on time */ - } else if (delta.tv_sec < 0) { - /* do nothing, timer is already late */ - } else { - /* timer is early due to a clock set */ - tstojiffie(&delta, - posix_clocks[timr->it_clock].res, - &exp); - timr->it.real.wall_to_prev = new_wall_to; - timr->it.real.timer.expires += exp; - add_timer(&timr->it.real.timer); - do_notify = 0; - } - spin_unlock(&abs_list.lock); - } - if (do_notify) { - int si_private=0; + if (timr->it.real.interval.tv64 != 0) + si_private = ++timr->it_requeue_pending; - if (timr->it.real.incr) - si_private = ++timr->it_requeue_pending; - else { - remove_from_abslist(timr); + if (posix_timer_event(timr, si_private)) { + /* + * signal was not sent because of sig_ignor + * we will not get a call back to restart it AND + * it should be restarted. + */ + if (timr->it.real.interval.tv64 != 0) { + timr->it_overrun += + hrtimer_forward(&timr->it.real.timer, + timr->it.real.interval); + ret = HRTIMER_RESTART; } - - if (posix_timer_event(timr, si_private)) - /* - * signal was not sent because of sig_ignor - * we will not get a call back to restart it AND - * it should be restarted. - */ - schedule_next_timer(timr); } - unlock_timer(timr, flags); /* hold thru abs lock to keep irq off */ -} + unlock_timer(timr, flags); + return ret; +} static inline struct task_struct * good_sigevent(sigevent_t * event) { @@ -597,8 +450,7 @@ sys_timer_create(const clockid_t which_clock, goto out; } spin_lock_irq(&idr_lock); - error = idr_get_new(&posix_timers_id, - (void *) new_timer, + error = idr_get_new(&posix_timers_id, (void *) new_timer, &new_timer_id); spin_unlock_irq(&idr_lock); if (error == -EAGAIN) @@ -698,26 +550,6 @@ out: return error; } -/* - * good_timespec - * - * This function checks the elements of a timespec structure. - * - * Arguments: - * ts : Pointer to the timespec structure to check - * - * Return value: - * If a NULL pointer was passed in, or the tv_nsec field was less than 0 - * or greater than NSEC_PER_SEC, or the tv_sec field was less than 0, - * this function returns 0. Otherwise it returns 1. - */ -static int good_timespec(const struct timespec *ts) -{ - if ((!ts) || !timespec_valid(ts)) - return 0; - return 1; -} - /* * Locking issues: We need to protect the result of the id look up until * we get the timer locked down so it is not deleted under us. The @@ -770,39 +602,39 @@ static struct k_itimer * lock_timer(timer_t timer_id, unsigned long *flags) static void common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) { - unsigned long expires; - struct now_struct now; - - do - expires = timr->it.real.timer.expires; - while ((volatile long) (timr->it.real.timer.expires) != expires); - - posix_get_now(&now); - - if (expires && - ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) && - !timr->it.real.incr && - posix_time_before(&timr->it.real.timer, &now)) - timr->it.real.timer.expires = expires = 0; - if (expires) { - if (timr->it_requeue_pending & REQUEUE_PENDING || - (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) { - posix_bump_timer(timr, now); - expires = timr->it.real.timer.expires; - } - else - if (!timer_pending(&timr->it.real.timer)) - expires = 0; - if (expires) - expires -= now.jiffies; - } - jiffies_to_timespec(expires, &cur_setting->it_value); - jiffies_to_timespec(timr->it.real.incr, &cur_setting->it_interval); + ktime_t remaining; + struct hrtimer *timer = &timr->it.real.timer; - if (cur_setting->it_value.tv_sec < 0) { - cur_setting->it_value.tv_nsec = 1; - cur_setting->it_value.tv_sec = 0; + memset(cur_setting, 0, sizeof(struct itimerspec)); + remaining = hrtimer_get_remaining(timer); + + /* Time left ? or timer pending */ + if (remaining.tv64 > 0 || hrtimer_active(timer)) + goto calci; + /* interval timer ? */ + if (timr->it.real.interval.tv64 == 0) + return; + /* + * When a requeue is pending or this is a SIGEV_NONE timer + * move the expiry time forward by intervals, so expiry is > + * now. + */ + if (timr->it_requeue_pending & REQUEUE_PENDING || + (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) { + timr->it_overrun += + hrtimer_forward(timer, timr->it.real.interval); + remaining = hrtimer_get_remaining(timer); } + calci: + /* interval timer ? */ + if (timr->it.real.interval.tv64 != 0) + cur_setting->it_interval = + ktime_to_timespec(timr->it.real.interval); + /* Return 0 only, when the timer is expired and not pending */ + if (remaining.tv64 <= 0) + cur_setting->it_value.tv_nsec = 1; + else + cur_setting->it_value = ktime_to_timespec(remaining); } /* Get the time remaining on a POSIX.1b interval timer. */ @@ -826,6 +658,7 @@ sys_timer_gettime(timer_t timer_id, struct itimerspec __user *setting) return 0; } + /* * Get the number of overruns of a POSIX.1b interval timer. This is to * be the overrun of the timer last delivered. At the same time we are @@ -835,7 +668,6 @@ sys_timer_gettime(timer_t timer_id, struct itimerspec __user *setting) * the call back to do_schedule_next_timer(). So all we need to do is * to pick up the frozen overrun. */ - asmlinkage long sys_timer_getoverrun(timer_t timer_id) { @@ -852,84 +684,6 @@ sys_timer_getoverrun(timer_t timer_id) return overrun; } -/* - * Adjust for absolute time - * - * If absolute time is given and it is not CLOCK_MONOTONIC, we need to - * adjust for the offset between the timer clock (CLOCK_MONOTONIC) and - * what ever clock he is using. - * - * If it is relative time, we need to add the current (CLOCK_MONOTONIC) - * time to it to get the proper time for the timer. - */ -static int adjust_abs_time(struct k_clock *clock, struct timespec *tp, - int abs, u64 *exp, struct timespec *wall_to) -{ - struct timespec now; - struct timespec oc = *tp; - u64 jiffies_64_f; - int rtn =0; - - if (abs) { - /* - * The mask pick up the 4 basic clocks - */ - if (!((clock - &posix_clocks[0]) & ~CLOCKS_MASK)) { - jiffies_64_f = do_posix_clock_monotonic_gettime_parts( - &now, wall_to); - /* - * If we are doing a MONOTONIC clock - */ - if((clock - &posix_clocks[0]) & CLOCKS_MONO){ - now.tv_sec += wall_to->tv_sec; - now.tv_nsec += wall_to->tv_nsec; - } - } else { - /* - * Not one of the basic clocks - */ - clock->clock_get(clock - posix_clocks, &now); - jiffies_64_f = get_jiffies_64(); - } - /* - * Take away now to get delta and normalize - */ - set_normalized_timespec(&oc, oc.tv_sec - now.tv_sec, - oc.tv_nsec - now.tv_nsec); - }else{ - jiffies_64_f = get_jiffies_64(); - } - /* - * Check if the requested time is prior to now (if so set now) - */ - if (oc.tv_sec < 0) - oc.tv_sec = oc.tv_nsec = 0; - - if (oc.tv_sec | oc.tv_nsec) - set_normalized_timespec(&oc, oc.tv_sec, - oc.tv_nsec + clock->res); - tstojiffie(&oc, clock->res, exp); - - /* - * Check if the requested time is more than the timer code - * can handle (if so we error out but return the value too). - */ - if (*exp > ((u64)MAX_JIFFY_OFFSET)) - /* - * This is a considered response, not exactly in - * line with the standard (in fact it is silent on - * possible overflows). We assume such a large - * value is ALMOST always a programming error and - * try not to compound it by setting a really dumb - * value. - */ - rtn = -EINVAL; - /* - * return the actual jiffies expire time, full 64 bits - */ - *exp += jiffies_64_f; - return rtn; -} /* Set a POSIX.1b interval timer. */ /* timr->it_lock is taken. */ @@ -937,68 +691,48 @@ static inline int common_timer_set(struct k_itimer *timr, int flags, struct itimerspec *new_setting, struct itimerspec *old_setting) { - struct k_clock *clock = &posix_clocks[timr->it_clock]; - u64 expire_64; + struct hrtimer *timer = &timr->it.real.timer; if (old_setting) common_timer_get(timr, old_setting); /* disable the timer */ - timr->it.real.incr = 0; + timr->it.real.interval.tv64 = 0; /* * careful here. If smp we could be in the "fire" routine which will * be spinning as we hold the lock. But this is ONLY an SMP issue. */ - if (try_to_del_timer_sync(&timr->it.real.timer) < 0) { -#ifdef CONFIG_SMP - /* - * It can only be active if on an other cpu. Since - * we have cleared the interval stuff above, it should - * clear once we release the spin lock. Of course once - * we do that anything could happen, including the - * complete melt down of the timer. So return with - * a "retry" exit status. - */ + if (hrtimer_try_to_cancel(timer) < 0) return TIMER_RETRY; -#endif - } - - remove_from_abslist(timr); timr->it_requeue_pending = (timr->it_requeue_pending + 2) & ~REQUEUE_PENDING; timr->it_overrun_last = 0; - timr->it_overrun = -1; - /* - *switch off the timer when it_value is zero - */ - if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec) { - timr->it.real.timer.expires = 0; - return 0; - } - if (adjust_abs_time(clock, - &new_setting->it_value, flags & TIMER_ABSTIME, - &expire_64, &(timr->it.real.wall_to_prev))) { - return -EINVAL; - } - timr->it.real.timer.expires = (unsigned long)expire_64; - tstojiffie(&new_setting->it_interval, clock->res, &expire_64); - timr->it.real.incr = (unsigned long)expire_64; + /* switch off the timer when it_value is zero */ + if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec) + return 0; - /* - * We do not even queue SIGEV_NONE timers! But we do put them - * in the abs list so we can do that right. + /* Posix madness. Only absolute CLOCK_REALTIME timers + * are affected by clock sets. So we must reiniatilize + * the timer. */ - if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)) - add_timer(&timr->it.real.timer); - - if (flags & TIMER_ABSTIME && clock->abs_struct) { - spin_lock(&clock->abs_struct->lock); - list_add_tail(&(timr->it.real.abs_timer_entry), - &(clock->abs_struct->list)); - spin_unlock(&clock->abs_struct->lock); - } + if (timr->it_clock == CLOCK_REALTIME && (flags & TIMER_ABSTIME)) + hrtimer_rebase(timer, CLOCK_REALTIME); + else + hrtimer_rebase(timer, CLOCK_MONOTONIC); + + timer->expires = timespec_to_ktime(new_setting->it_value); + + /* Convert interval */ + 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)) + return 0; + + hrtimer_start(timer, timer->expires, (flags & TIMER_ABSTIME) ? + HRTIMER_ABS : HRTIMER_REL); return 0; } @@ -1020,8 +754,8 @@ sys_timer_settime(timer_t timer_id, int flags, if (copy_from_user(&new_spec, new_setting, sizeof (new_spec))) return -EFAULT; - if ((!good_timespec(&new_spec.it_interval)) || - (!good_timespec(&new_spec.it_value))) + if (!timespec_valid(&new_spec.it_interval) || + !timespec_valid(&new_spec.it_value)) return -EINVAL; retry: timr = lock_timer(timer_id, &flag); @@ -1037,8 +771,8 @@ retry: goto retry; } - if (old_setting && !error && copy_to_user(old_setting, - &old_spec, sizeof (old_spec))) + if (old_setting && !error && + copy_to_user(old_setting, &old_spec, sizeof (old_spec))) error = -EFAULT; return error; @@ -1046,24 +780,10 @@ retry: static inline int common_timer_del(struct k_itimer *timer) { - timer->it.real.incr = 0; + timer->it.real.interval.tv64 = 0; - if (try_to_del_timer_sync(&timer->it.real.timer) < 0) { -#ifdef CONFIG_SMP - /* - * It can only be active if on an other cpu. Since - * we have cleared the interval stuff above, it should - * clear once we release the spin lock. Of course once - * we do that anything could happen, including the - * complete melt down of the timer. So return with - * a "retry" exit status. - */ + if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0) return TIMER_RETRY; -#endif - } - - remove_from_abslist(timer); - return 0; } @@ -1079,24 +799,16 @@ sys_timer_delete(timer_t timer_id) struct k_itimer *timer; long flags; -#ifdef CONFIG_SMP - int error; retry_delete: -#endif timer = lock_timer(timer_id, &flags); if (!timer) return -EINVAL; -#ifdef CONFIG_SMP - error = timer_delete_hook(timer); - - if (error == TIMER_RETRY) { + if (timer_delete_hook(timer) == TIMER_RETRY) { unlock_timer(timer, flags); goto retry_delete; } -#else - timer_delete_hook(timer); -#endif + spin_lock(¤t->sighand->siglock); list_del(&timer->list); spin_unlock(¤t->sighand->siglock); @@ -1113,6 +825,7 @@ retry_delete: release_posix_timer(timer, IT_ID_SET); return 0; } + /* * return timer owned by the process, used by exit_itimers */ @@ -1120,22 +833,13 @@ static inline void itimer_delete(struct k_itimer *timer) { unsigned long flags; -#ifdef CONFIG_SMP - int error; retry_delete: -#endif spin_lock_irqsave(&timer->it_lock, flags); -#ifdef CONFIG_SMP - error = timer_delete_hook(timer); - - if (error == TIMER_RETRY) { + if (timer_delete_hook(timer) == TIMER_RETRY) { unlock_timer(timer, flags); goto retry_delete; } -#else - timer_delete_hook(timer); -#endif list_del(&timer->list); /* * This keeps any tasks waiting on the spin lock from thinking @@ -1164,57 +868,7 @@ void exit_itimers(struct signal_struct *sig) } } -/* - * And now for the "clock" calls - * - * These functions are called both from timer functions (with the timer - * spin_lock_irq() held and from clock calls with no locking. They must - * use the save flags versions of locks. - */ - -/* - * We do ticks here to avoid the irq lock ( they take sooo long). - * The seqlock is great here. Since we a reader, we don't really care - * if we are interrupted since we don't take lock that will stall us or - * any other cpu. Voila, no irq lock is needed. - * - */ - -static u64 do_posix_clock_monotonic_gettime_parts( - struct timespec *tp, struct timespec *mo) -{ - u64 jiff; - unsigned int seq; - - do { - seq = read_seqbegin(&xtime_lock); - getnstimeofday(tp); - *mo = wall_to_monotonic; - jiff = jiffies_64; - - } while(read_seqretry(&xtime_lock, seq)); - - return jiff; -} - -static int do_posix_clock_monotonic_get(const clockid_t clock, - struct timespec *tp) -{ - struct timespec wall_to_mono; - - do_posix_clock_monotonic_gettime_parts(tp, &wall_to_mono); - - set_normalized_timespec(tp, tp->tv_sec + wall_to_mono.tv_sec, - tp->tv_nsec + wall_to_mono.tv_nsec); - - return 0; -} - -int do_posix_clock_monotonic_gettime(struct timespec *tp) -{ - return do_posix_clock_monotonic_get(CLOCK_MONOTONIC, tp); -} - +/* Not available / possible... functions */ int do_posix_clock_nosettime(const clockid_t clockid, struct timespec *tp) { return -EINVAL; @@ -1287,107 +941,6 @@ sys_clock_getres(const clockid_t which_clock, struct timespec __user *tp) return error; } -/* - * The standard says that an absolute nanosleep call MUST wake up at - * the requested time in spite of clock settings. Here is what we do: - * For each nanosleep call that needs it (only absolute and not on - * CLOCK_MONOTONIC* (as it can not be set)) we thread a little structure - * into the "nanosleep_abs_list". All we need is the task_struct pointer. - * When ever the clock is set we just wake up all those tasks. The rest - * is done by the while loop in clock_nanosleep(). - * - * On locking, clock_was_set() is called from update_wall_clock which - * holds (or has held for it) a write_lock_irq( xtime_lock) and is - * called from the timer bh code. Thus we need the irq save locks. - * - * Also, on the call from update_wall_clock, that is done as part of a - * softirq thing. We don't want to delay the system that much (possibly - * long list of timers to fix), so we defer that work to keventd. - */ - -static DECLARE_WAIT_QUEUE_HEAD(nanosleep_abs_wqueue); -static DECLARE_WORK(clock_was_set_work, (void(*)(void*))clock_was_set, NULL); - -static DECLARE_MUTEX(clock_was_set_lock); - -void clock_was_set(void) -{ - struct k_itimer *timr; - struct timespec new_wall_to; - LIST_HEAD(cws_list); - unsigned long seq; - - - if (unlikely(in_interrupt())) { - schedule_work(&clock_was_set_work); - return; - } - wake_up_all(&nanosleep_abs_wqueue); - - /* - * Check if there exist TIMER_ABSTIME timers to correct. - * - * Notes on locking: This code is run in task context with irq - * on. We CAN be interrupted! All other usage of the abs list - * lock is under the timer lock which holds the irq lock as - * well. We REALLY don't want to scan the whole list with the - * interrupt system off, AND we would like a sequence lock on - * this code as well. Since we assume that the clock will not - * be set often, it seems ok to take and release the irq lock - * for each timer. In fact add_timer will do this, so this is - * not an issue. So we know when we are done, we will move the - * whole list to a new location. Then as we process each entry, - * we will move it to the actual list again. This way, when our - * copy is empty, we are done. We are not all that concerned - * about preemption so we will use a semaphore lock to protect - * aginst reentry. This way we will not stall another - * processor. It is possible that this may delay some timers - * that should have expired, given the new clock, but even this - * will be minimal as we will always update to the current time, - * even if it was set by a task that is waiting for entry to - * this code. Timers that expire too early will be caught by - * the expire code and restarted. - - * Absolute timers that repeat are left in the abs list while - * waiting for the task to pick up the signal. This means we - * may find timers that are not in the "add_timer" list, but are - * in the abs list. We do the same thing for these, save - * putting them back in the "add_timer" list. (Note, these are - * left in the abs list mainly to indicate that they are - * ABSOLUTE timers, a fact that is used by the re-arm code, and - * for which we have no other flag.) - - */ - - down(&clock_was_set_lock); - spin_lock_irq(&abs_list.lock); - list_splice_init(&abs_list.list, &cws_list); - spin_unlock_irq(&abs_list.lock); - do { - do { - seq = read_seqbegin(&xtime_lock); - new_wall_to = wall_to_monotonic; - } while (read_seqretry(&xtime_lock, seq)); - - spin_lock_irq(&abs_list.lock); - if (list_empty(&cws_list)) { - spin_unlock_irq(&abs_list.lock); - break; - } - timr = list_entry(cws_list.next, struct k_itimer, - it.real.abs_timer_entry); - - list_del_init(&timr->it.real.abs_timer_entry); - if (add_clockset_delta(timr, &new_wall_to) && - del_timer(&timr->it.real.timer)) /* timer run yet? */ - add_timer(&timr->it.real.timer); - list_add(&timr->it.real.abs_timer_entry, &abs_list.list); - spin_unlock_irq(&abs_list.lock); - } while (1); - - up(&clock_was_set_lock); -} - /* * nanosleep for monotonic and realtime clocks */ @@ -1401,7 +954,7 @@ static int common_nsleep(const clockid_t which_clock, int flags, case CLOCK_REALTIME: /* Posix madness. Only absolute timers on clock realtime are affected by clock set. */ - if (mode == HRTIMER_ABS) + if (mode != HRTIMER_ABS) clockid = CLOCK_MONOTONIC; case CLOCK_MONOTONIC: break; -- cgit v1.2.3-58-ga151