bionic (3) clReleaseEvent.3clc.gz

Provided by: opencl-1.2-man-doc_1.0~svn33624-1_all bug

NAME

       clReleaseEvent - Decrements the event reference count.

       cl_int clReleaseEvent(cl_event event);

PARAMETERS

       event
           Event object being released.

NOTES

       Decrements the event reference count.

       The event object is deleted once the reference count becomes zero, the specific command identified by
       this event has completed (or terminated) and there are no commands in the command-queues of a context
       that require a wait for this event to complete.

       Developers should be careful when releasing their last reference count on events created by
       clCreateUserEvent(3clc) that have not yet been set to status of CL_COMPLETE or an error. If the user
       event was used in the event_wait_list argument passed to a clEnqueue*** API or another application host
       thread is waiting for it in clWaitForEvents(3clc), those commands and host threads will continue to wait
       for the event status to reach CL_COMPLETE or error, even after the user has released the object. Since in
       this scenario the developer has released his last reference count to the user event, it would be in
       principle no longer valid for him to change the status of the event to unblock all the other machinery.
       As a result the waiting tasks will wait forever, and associated events, cl_mem objects, command queues
       and contexts are likely to leak. In-order command queues caught up in this deadlock may cease to do any
       work.

ERRORS

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

       •   CL_INVALID_EVENT if event is not a valid event object.

       •   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.

SPECIFICATION

       OpenCL Specification[1]

SEE ALSO

       clGetEventInfo(3clc), clRetainEvent(3clc), clWaitForEvents(3clc)

AUTHORS

       The Khronos Group

       Copyright © 2007-2011 The Khronos Group Inc.
       Permission is hereby granted, free of charge, to any person obtaining a copy of this software and/or
       associated documentation files (the "Materials"), to deal in the Materials without restriction, including
       without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
       copies of the Materials, and to permit persons to whom the Materials are furnished to do so, subject to
       the condition that this copyright notice and permission notice shall be included in all copies or
       substantial portions of the Materials.

NOTES

        1. OpenCL Specification
           page 185, section 5.9 - Event Objects