Don't suspend scheduler if task already notified (#1190)
* Don't suspend scheduler if task already notified
diff --git a/tasks.c b/tasks.c
index 421dea7..22e11f0 100644
--- a/tasks.c
+++ b/tasks.c
@@ -7659,24 +7659,27 @@
configASSERT( uxIndexToWaitOn < configTASK_NOTIFICATION_ARRAY_ENTRIES );
- /* We suspend the scheduler here as prvAddCurrentTaskToDelayedList is a
- * non-deterministic operation. */
- vTaskSuspendAll();
+ /* If the notification count is zero, and if we are willing to wait for a
+ * notification, then block the task and wait. */
+ if( ( pxCurrentTCB->ulNotifiedValue[ uxIndexToWaitOn ] == 0U ) && ( xTicksToWait > ( TickType_t ) 0 ) )
{
- /* We MUST enter a critical section to atomically check if a notification
- * has occurred and set the flag to indicate that we are waiting for
- * a notification. If we do not do so, a notification sent from an ISR
- * will get lost. */
- taskENTER_CRITICAL();
+ /* We suspend the scheduler here as prvAddCurrentTaskToDelayedList is a
+ * non-deterministic operation. */
+ vTaskSuspendAll();
{
- /* Only block if the notification count is not already non-zero. */
- if( pxCurrentTCB->ulNotifiedValue[ uxIndexToWaitOn ] == 0U )
+ /* We MUST enter a critical section to atomically check if a notification
+ * has occurred and set the flag to indicate that we are waiting for
+ * a notification. If we do not do so, a notification sent from an ISR
+ * will get lost. */
+ taskENTER_CRITICAL();
{
- /* Mark this task as waiting for a notification. */
- pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] = taskWAITING_NOTIFICATION;
-
- if( xTicksToWait > ( TickType_t ) 0 )
+ /* Only block if the notification count is not already non-zero. */
+ if( pxCurrentTCB->ulNotifiedValue[ uxIndexToWaitOn ] == 0U )
{
+ /* Mark this task as waiting for a notification. */
+ pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] = taskWAITING_NOTIFICATION;
+
+ /* Arrange to wait for a notification. */
xShouldBlock = pdTRUE;
}
else
@@ -7684,37 +7687,33 @@
mtCOVERAGE_TEST_MARKER();
}
}
+ taskEXIT_CRITICAL();
+
+ /* We are now out of the critical section but the scheduler is still
+ * suspended, so we are safe to do non-deterministic operations such
+ * as prvAddCurrentTaskToDelayedList. */
+ if( xShouldBlock == pdTRUE )
+ {
+ traceTASK_NOTIFY_TAKE_BLOCK( uxIndexToWaitOn );
+ prvAddCurrentTaskToDelayedList( xTicksToWait, pdTRUE );
+ }
else
{
mtCOVERAGE_TEST_MARKER();
}
}
- taskEXIT_CRITICAL();
+ xAlreadyYielded = xTaskResumeAll();
- /* We are now out of the critical section but the scheduler is still
- * suspended, so we are safe to do non-deterministic operations such
- * as prvAddCurrentTaskToDelayedList. */
- if( xShouldBlock == pdTRUE )
+ /* Force a reschedule if xTaskResumeAll has not already done so. */
+ if( ( xShouldBlock == pdTRUE ) && ( xAlreadyYielded == pdFALSE ) )
{
- traceTASK_NOTIFY_TAKE_BLOCK( uxIndexToWaitOn );
- prvAddCurrentTaskToDelayedList( xTicksToWait, pdTRUE );
+ taskYIELD_WITHIN_API();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
- xAlreadyYielded = xTaskResumeAll();
-
- /* Force a reschedule if xTaskResumeAll has not already done so. */
- if( ( xShouldBlock == pdTRUE ) && ( xAlreadyYielded == pdFALSE ) )
- {
- taskYIELD_WITHIN_API();
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
taskENTER_CRITICAL();
{
@@ -7763,28 +7762,31 @@
configASSERT( uxIndexToWaitOn < configTASK_NOTIFICATION_ARRAY_ENTRIES );
- /* We suspend the scheduler here as prvAddCurrentTaskToDelayedList is a
- * non-deterministic operation. */
- vTaskSuspendAll();
+ /* If the task hasn't received a notification, and if we are willing to wait
+ * for it, then block the task and wait. */
+ if( ( pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] != taskNOTIFICATION_RECEIVED ) && ( xTicksToWait > ( TickType_t ) 0 ) )
{
- /* We MUST enter a critical section to atomically check and update the
- * task notification value. If we do not do so, a notification from
- * an ISR will get lost. */
- taskENTER_CRITICAL();
+ /* We suspend the scheduler here as prvAddCurrentTaskToDelayedList is a
+ * non-deterministic operation. */
+ vTaskSuspendAll();
{
- /* Only block if a notification is not already pending. */
- if( pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] != taskNOTIFICATION_RECEIVED )
+ /* We MUST enter a critical section to atomically check and update the
+ * task notification value. If we do not do so, a notification from
+ * an ISR will get lost. */
+ taskENTER_CRITICAL();
{
- /* Clear bits in the task's notification value as bits may get
- * set by the notifying task or interrupt. This can be used
- * to clear the value to zero. */
- pxCurrentTCB->ulNotifiedValue[ uxIndexToWaitOn ] &= ~ulBitsToClearOnEntry;
-
- /* Mark this task as waiting for a notification. */
- pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] = taskWAITING_NOTIFICATION;
-
- if( xTicksToWait > ( TickType_t ) 0 )
+ /* Only block if a notification is not already pending. */
+ if( pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] != taskNOTIFICATION_RECEIVED )
{
+ /* Clear bits in the task's notification value as bits may get
+ * set by the notifying task or interrupt. This can be used
+ * to clear the value to zero. */
+ pxCurrentTCB->ulNotifiedValue[ uxIndexToWaitOn ] &= ~ulBitsToClearOnEntry;
+
+ /* Mark this task as waiting for a notification. */
+ pxCurrentTCB->ucNotifyState[ uxIndexToWaitOn ] = taskWAITING_NOTIFICATION;
+
+ /* Arrange to wait for a notification. */
xShouldBlock = pdTRUE;
}
else
@@ -7792,37 +7794,33 @@
mtCOVERAGE_TEST_MARKER();
}
}
+ taskEXIT_CRITICAL();
+
+ /* We are now out of the critical section but the scheduler is still
+ * suspended, so we are safe to do non-deterministic operations such
+ * as prvAddCurrentTaskToDelayedList. */
+ if( xShouldBlock == pdTRUE )
+ {
+ traceTASK_NOTIFY_WAIT_BLOCK( uxIndexToWaitOn );
+ prvAddCurrentTaskToDelayedList( xTicksToWait, pdTRUE );
+ }
else
{
mtCOVERAGE_TEST_MARKER();
}
}
- taskEXIT_CRITICAL();
+ xAlreadyYielded = xTaskResumeAll();
- /* We are now out of the critical section but the scheduler is still
- * suspended, so we are safe to do non-deterministic operations such
- * as prvAddCurrentTaskToDelayedList. */
- if( xShouldBlock == pdTRUE )
+ /* Force a reschedule if xTaskResumeAll has not already done so. */
+ if( ( xShouldBlock == pdTRUE ) && ( xAlreadyYielded == pdFALSE ) )
{
- traceTASK_NOTIFY_WAIT_BLOCK( uxIndexToWaitOn );
- prvAddCurrentTaskToDelayedList( xTicksToWait, pdTRUE );
+ taskYIELD_WITHIN_API();
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
- xAlreadyYielded = xTaskResumeAll();
-
- /* Force a reschedule if xTaskResumeAll has not already done so. */
- if( ( xShouldBlock == pdTRUE ) && ( xAlreadyYielded == pdFALSE ) )
- {
- taskYIELD_WITHIN_API();
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
taskENTER_CRITICAL();
{
