diff options
| author | Keith Packard <keithp@keithp.com> | 2012-10-25 13:40:54 -0700 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2012-10-26 14:07:04 -0700 |
| commit | ccf0faa7d26d56deca7928b521d07be40504466a (patch) | |
| tree | a7faa1cc9e2998e8e0754b3af939c030019405e4 /src/core | |
| parent | 9b978cd467f9128f3069765dd8fbf8abad3459a4 (diff) | |
altos: Leave interrupts disabled while checking for task to run
Otherwise, we run the risk of an interrupt waking a task after we've
decided to idle the CPU.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src/core')
| -rw-r--r-- | src/core/ao_task.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/src/core/ao_task.c b/src/core/ao_task.c index a11979f0..985c37fa 100644 --- a/src/core/ao_task.c +++ b/src/core/ao_task.c @@ -331,6 +331,7 @@ ao_yield(void) ao_arch_naked_define } ao_arch_isr_stack(); + ao_arch_block_interrupts(); #if AO_CHECK_STACK in_yield = 1; @@ -339,21 +340,19 @@ ao_yield(void) ao_arch_naked_define * this loop will run forever, which is just fine */ #if HAS_TASK_QUEUE - if (ao_cur_task->wchan == NULL) { - uint32_t flags; - flags = ao_arch_irqsave(); + /* If the current task is running, move it to the + * end of the queue to allow other tasks a chance + */ + if (ao_cur_task->wchan == NULL) ao_task_to_run_queue(ao_cur_task); - ao_arch_irqrestore(flags); - } ao_cur_task = NULL; - for (;;) { ao_arch_memory_barrier(); if (!ao_list_is_empty(&run_queue)) break; - ao_arch_cpu_idle(); + /* Wait for interrupts when there's nothing ready */ + ao_arch_wait_interrupt(); } - ao_cur_task = ao_list_first_entry(&run_queue, struct ao_task, queue); #else { @@ -374,20 +373,19 @@ ao_yield(void) ao_arch_naked_define (int16_t) (ao_time() - ao_cur_task->alarm) >= 0) break; - /* Enter lower power mode when there isn't anything to do */ + /* Wait for interrupts when there's nothing ready */ if (ao_cur_task_index == ao_last_task_index) - ao_arch_cpu_idle(); + ao_arch_wait_interrupt(); } -#if HAS_SAMPLE_PROFILE - ao_cur_task->start = ao_sample_profile_timer_value(); -#endif } #endif +#if HAS_SAMPLE_PROFILE + ao_cur_task->start = ao_sample_profile_timer_value(); +#endif #if HAS_STACK_GUARD ao_mpu_stack_guard(ao_cur_task->stack); #endif #if AO_CHECK_STACK - ao_arch_block_interrupts(); in_yield = 0; #endif ao_arch_restore_stack(); @@ -519,7 +517,7 @@ ao_task_info(void) task->name, (int) task->wchan); } -#if HAS_TASK_QUEUE +#if HAS_TASK_QUEUE && DEBUG ao_task_validate(); #endif } |