altos: Leave interrupts disabled while checking for task to run

[fw/altos] / src / core / ao_task.c

diff --git a/src/core/ao_task.c b/src/core/ao_task.c
index a11979f0a81fb78a5063ee9066189647c649285e..985c37fa79953849f6237dd475879e92aa7231cb 100644 (file)
--- 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
 }