From 3c924116ee66c8c3878cb14cf388ff339061fc95 Mon Sep 17 00:00:00 2001 From: Matheus Date: Thu, 12 Sep 2024 20:21:06 -0300 Subject: [PATCH] timer: fix overflow bug --- kernel-src/sys/timer.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/kernel-src/sys/timer.c b/kernel-src/sys/timer.c index 73c7bab5..acc4f977 100644 --- a/kernel-src/sys/timer.c +++ b/kernel-src/sys/timer.c @@ -5,6 +5,10 @@ static void insert(timer_t *timer, timerentry_t *entry, time_t us) { entry->absolutetick = timer->tickcurrent + us * timer->ticksperus; + // it overflowed, this will be so far into the future we can just + // set it to be far off enough into the future that it really does not matter. + if (entry->absolutetick < timer->tickcurrent) + entry->absolutetick = timer->ticksperus * 1000 * 1000 * 60 * 60 * 24 * 30 * 12 * 1000; // a thousand years from now. if (timer->queue == NULL) { // if no other entries in the queue entry->next = NULL; @@ -32,7 +36,7 @@ static void insert(timer_t *timer, timerentry_t *entry, time_t us) { } } -// expects IPL to be at least IPL_DPC +// expects IPL to be at least IPL_TIMER static void timercheck(timer_t *timer) { while (timer->queue && timer->queue->absolutetick == timer->tickcurrent) { timerentry_t *entry = timer->queue; @@ -127,11 +131,12 @@ void timer_insert(timer_t *timer, timerentry_t *entry, dpcfn_t fn, dpcarg_t arg, } uintmax_t timer_remove(timer_t *timer, timerentry_t *entry) { - timer_stop(timer); - long oldipl = interrupt_raiseipl(IPL_TIMER); spinlock_acquire(&timer->lock); + if (timer->running) + timer->tickcurrent += timer->stop(timer); + uintmax_t timeremaining = 0; // if it had already fired by the time the lock was reached @@ -154,14 +159,18 @@ uintmax_t timer_remove(timer_t *timer, timerentry_t *entry) { prev->next = iterator->next; iterator->next = NULL; + // ALWAYS round up the time remaining timeremaining = ROUND_UP(iterator->absolutetick - timer->tickcurrent, timer->ticksperus) / timer->ticksperus; + if (timer->queue) { + timercheck(timer); + timer->arm(timer->queue->absolutetick - timer->tickcurrent); + } + cleanup: spinlock_release(&timer->lock); interrupt_loweripl(oldipl); - - timer_resume(timer); return timeremaining; }