C Specification

To enqueue a marker command which waits for events or commands to complete, call the function

// Provided by CL_VERSION_1_2
cl_int clEnqueueMarkerWithWaitList(
    cl_command_queue command_queue,
    cl_uint num_events_in_wait_list,
    const cl_event* event_wait_list,
    cl_event* event);
clEnqueueMarkerWithWaitList is missing before version 1.2.

Parameters

  • command_queue is a valid host command-queue.

  • event_wait_list and num_events_in_wait_list specify events that need to complete before this particular command can be executed.

  • event returns an event object that identifies this command and can be used to query or wait for this command to complete. If event is NULL or the enqueue is unsuccessful, no event will be created and therefore it will not be possible to query the status of this command or to wait for this command to complete. If event_wait_list and event are not NULL, event must not refer to an element of the event_wait_list array.

Description

If event_wait_list is NULL, num_events_in_wait_list must be 0. If event_wait_list is not NULL, the list of events pointed to by event_wait_list must be valid and num_events_in_wait_list must be greater than 0. The events specified in event_wait_list act as synchronization points. The context associated with events in event_wait_list and command_queue must be the same. The memory associated with event_wait_list can be reused or freed after the function returns.

If event_wait_list is NULL, then this particular command waits until all previous enqueued commands to command_queue have completed.

The marker command either waits for a list of events to complete, or if the list is empty it waits for all commands previously enqueued in command_queue to complete before it completes. This command returns an event which can be waited on, i.e. this event can be waited on to insure that all events either in the event_wait_list or all previously enqueued commands, queued before this command to command_queue, have completed.

clEnqueueMarkerWithWaitList returns CL_SUCCESS if the function is successfully executed. Otherwise, it returns one of the following errors:

  • CL_INVALID_COMMAND_QUEUE if command_queue is not a valid host command-queue.

  • CL_INVALID_CONTEXT if context associated with command_queue and events in event_wait_list are not the same.

  • CL_INVALID_EVENT_WAIT_LIST if event_wait_list is NULL and num_events_in_wait_list > 0, or event_wait_list is not NULL and num_events_in_wait_list is 0, or if event objects in event_wait_list are not valid events.

  • CL_OUT_OF_RESOURCES if there is a failure to allocate resources required by the OpenCL implementation on the device.

  • CL_OUT_OF_HOST_MEMORY if there is a failure to allocate resources required by the OpenCL implementation on the host.

See Also

CL_VERSION_1_2, cl_command_queue, cl_event, cl_uint

Document Notes

For more information, see the OpenCL Specification

This page is extracted from the OpenCL Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2025 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0