diff options
Diffstat (limited to 'src/linux/timer.c')
| -rw-r--r-- | src/linux/timer.c | 68 |
1 files changed, 37 insertions, 31 deletions
diff --git a/src/linux/timer.c b/src/linux/timer.c index dd63f66f..06330830 100644 --- a/src/linux/timer.c +++ b/src/linux/timer.c @@ -12,15 +12,24 @@ #include "internal.h" // console_sleep #include "sched.h" // DECL_INIT +// Global storage for timer handling +static struct { + // Last time reported by timer_read_time() + uint32_t last_read_time; + // Fields for converting from a systime to ticks + time_t start_sec; + // Maximum absolute time that can be spent in timer_dispatch() + uint32_t timer_repeat_until; + // Time of next software timer (also used to convert from ticks to systime) + uint32_t next_wake_counter; + struct timespec next_wake; +} TimerInfo; + /**************************************************************** * Timespec helpers ****************************************************************/ -static uint32_t next_wake_time_counter; -static struct timespec next_wake_time; -static time_t start_sec; - // Compare two 'struct timespec' times static inline uint8_t timespec_is_before(struct timespec ts1, struct timespec ts2) @@ -33,7 +42,7 @@ timespec_is_before(struct timespec ts1, struct timespec ts2) static inline uint32_t timespec_to_time(struct timespec ts) { - return ((ts.tv_sec - start_sec) * CONFIG_CLOCK_FREQ + return ((ts.tv_sec - TimerInfo.start_sec) * CONFIG_CLOCK_FREQ + ts.tv_nsec / NSECS_PER_TICK); } @@ -41,10 +50,10 @@ timespec_to_time(struct timespec ts) static inline struct timespec timespec_from_time(uint32_t time) { - int32_t counter_diff = time - next_wake_time_counter; + int32_t counter_diff = time - TimerInfo.next_wake_counter; struct timespec ts; - ts.tv_sec = next_wake_time.tv_sec; - ts.tv_nsec = next_wake_time.tv_nsec + counter_diff * NSECS_PER_TICK; + ts.tv_sec = TimerInfo.next_wake.tv_sec; + ts.tv_nsec = TimerInfo.next_wake.tv_nsec + counter_diff * NSECS_PER_TICK; if ((unsigned long)ts.tv_nsec >= NSECS) { if (ts.tv_nsec < 0) { ts.tv_sec--; @@ -70,9 +79,9 @@ timespec_read(void) int timer_check_periodic(struct timespec *ts) { - if (timespec_is_before(next_wake_time, *ts)) + if (timespec_is_before(TimerInfo.next_wake, *ts)) return 0; - *ts = next_wake_time; + *ts = TimerInfo.next_wake; ts->tv_sec += 2; return 1; } @@ -100,14 +109,12 @@ timer_is_before(uint32_t time1, uint32_t time2) return (int32_t)(time1 - time2) < 0; } -static uint32_t last_timer_read_time; - // Return the current time (in clock ticks) uint32_t timer_read_time(void) { uint32_t t = timespec_to_time(timespec_read()); - last_timer_read_time = t; + TimerInfo.last_read_time = t; return t; } @@ -115,11 +122,10 @@ timer_read_time(void) void timer_kick(void) { - next_wake_time = timespec_read(); - next_wake_time_counter = timespec_to_time(next_wake_time); + TimerInfo.next_wake = timespec_read(); + TimerInfo.next_wake_counter = timespec_to_time(TimerInfo.next_wake); } -static uint32_t timer_repeat_until; #define TIMER_IDLE_REPEAT_TICKS timer_from_us(500) #define TIMER_REPEAT_TICKS timer_from_us(100) @@ -130,16 +136,16 @@ static uint32_t timer_repeat_until; static uint32_t timer_dispatch_many(void) { - uint32_t tru = timer_repeat_until, prev_ltrt = 0; + uint32_t tru = TimerInfo.timer_repeat_until, prev_lrt = 0; for (;;) { // Run the next software timer uint32_t next = sched_timer_dispatch(); - uint32_t ltrt = last_timer_read_time; - if (!timer_is_before(ltrt, next) && !timer_is_before(tru, ltrt) - && ltrt != prev_ltrt) { + uint32_t lrt = TimerInfo.last_read_time; + if (!timer_is_before(lrt, next) && !timer_is_before(tru, lrt) + && lrt != prev_lrt) { // Can run next timer without overhead of calling timer_read_time() - prev_ltrt = ltrt; + prev_lrt = lrt; continue; } @@ -154,10 +160,10 @@ timer_dispatch_many(void) if (diff < (int32_t)(-timer_from_us(100000))) try_shutdown("Rescheduled timer in the past"); if (sched_tasks_busy()) { - timer_repeat_until = now + TIMER_REPEAT_TICKS; + TimerInfo.timer_repeat_until = now + TIMER_REPEAT_TICKS; return now + TIMER_DEFER_REPEAT_TICKS; } - timer_repeat_until = tru = now + TIMER_IDLE_REPEAT_TICKS; + TimerInfo.timer_repeat_until = tru = now + TIMER_IDLE_REPEAT_TICKS; } // Next timer in the past or near future - wait for it to be ready @@ -170,10 +176,10 @@ timer_dispatch_many(void) void timer_task(void) { - uint32_t now = last_timer_read_time; + uint32_t lrt = TimerInfo.last_read_time; irq_disable(); - if (timer_is_before(timer_repeat_until, now)) - timer_repeat_until = now; + if (timer_is_before(TimerInfo.timer_repeat_until, lrt)) + TimerInfo.timer_repeat_until = lrt; irq_enable(); } DECL_TASK(timer_task); @@ -183,14 +189,14 @@ static void timer_dispatch(void) { uint32_t next = timer_dispatch_many(); - next_wake_time = timespec_from_time(next); - next_wake_time_counter = next; + TimerInfo.next_wake = timespec_from_time(next); + TimerInfo.next_wake_counter = next; } void timer_init(void) { - start_sec = timespec_read().tv_sec + 1; + TimerInfo.start_sec = timespec_read().tv_sec + 1; timer_kick(); } DECL_INIT(timer_init); @@ -224,12 +230,12 @@ irq_restore(irqstatus_t flag) void irq_wait(void) { - console_sleep(next_wake_time); + console_sleep(TimerInfo.next_wake); } void irq_poll(void) { - if (!timespec_is_before(timespec_read(), next_wake_time)) + if (!timespec_is_before(timespec_read(), TimerInfo.next_wake)) timer_dispatch(); } |