Function: record_event

aclError aclrtRecordEvent(aclrtEvent event, aclrtStream stream)

ret = acl.rt.record_event(event, stream)

Records an event in a stream. When this API is called, pyACL captures the tasks delivered on the current stream and records them in the event. Therefore, you can later call acl.rt.query_event_status to check whether all tasks captured in the event are completed or call acl.rt.stream_wait_event to wait until all tasks are completed.

For events created using acl rt.create_event_ex_with_flag:

• This API supports event reuse for multiple records of the same event. Each record captures the tasks that have been delivered on the current stream and overwrites the tasks in the event. When acl.rt.stream_wait_event is called, the task saved in the latest event is used and will not be affected by subsequent calling of acl.rt.record_event.
• Before this API is called for the first time, ACL_EVENT_RECORDED_STATUS_COMPLETE is returned when acl.rt.query_event_status is called because there is no task in the event.

event: int, pointer address of the event to be recorded.

stream: int. Record the event in the specified stream (pointer address). If the default stream is used, set this parameter to 0.

ret: int, error code.

• 0 indicates success.
• Other values indicate failure.

• This API is asynchronous. The API call delivers a task rather than executes a task. After this API is called, call the synchronization API (for example, acl.rt.synchronize_stream) to ensure that the task is complete.
• acl.rt.record_event and acl.rt.stream_wait_event are used in conjunction for synchronization between streams. When acl.rt.record_event is called, an event resource is allocated. After acl.rt.stream_wait_event is called, acl.rt.reset_event should be called to free the event resource in a timely manner.

  API call sequence: acl.rt.create_event-->acl.rt.record_event-->acl.rt.stream_wait_event-->acl.rt.reset_event

For the API call example, see Event Synchronization and Inter-Stream Synchronization.