EXT_win32_keyed_mutex

GL_EXT_win32_keyed_mutex

Carsten Rohde, NVIDIA
James Jones, NVIDIA

James Jones, NVIDIA (jajones 'at' nvidia.com)

Complete

Last Modified Date: June 6, 2017
Revision: 2

506
OpenGL ES Extension #283

Written against the OpenGL 4.5 and OpenGL ES 3.2 specifications.

Requires GL_EXT_memory_object.

Direct3D image objects may have a built-in synchronization primitive
associated with them that can be used to synchronize access to their
contents across process and API boundaries.  This extension provides
access to that synchronization primitive via two new commands that
operate on GL memory objects.

boolean AcquireKeyedMutexWin32EXT(uint memory,
                                  uint64 key,
                                  uint timeout);

boolean ReleaseKeyedMutexWin32EXT(uint memory,
                                  uint64 key);

Add a new section between sections 4.1, "Sync Objects and Fences"
and section 4.2, "Query Objects and Asynchronous Queries"

    4.2 Memory Object Keyed Mutexes

    Memory objects imported with the handle types
    HANDLE_TYPE_D3D11_IMAGE_EXT and HANDLE_TYPE_D3D11_KMT_IMAGE_EXT may
    have a synchronization object known as a keyed mutex associated with
    them.  The exact behavior and conditions governing availability of
    these objects is beyond the scope of this specification, but their
    state can be manipulated by performing operations on the memory
    object with which they are associated.

    To block GL command processing until a keyed mutex is acquired, call

        boolean AcquireKeyedMutexWin32EXT(uint memory,
                                          uint64 key,
                                          uint timeout);

    where <memory> identifies which keyed mutex to acquire, <key> is the
    mutex value to wait for, and <timeout> is the time, in milliseconds,
    to wait before failing the acquire operation.

    FALSE is returned if the acquire operation timed out or failed.  No
    error is generated if the operation failed because it timed out.
    TRUE is returned if the wait succeeded.

    To release a keyed mutex after all prior GL command processing has
    completed, call

        boolean ReleaseKeyedMutexWin32EXT(uint memory,
                                          uint64 key);

    where <memory> identifies the keyed mutex to release, and <key> is
    the mutex value set by the release operation.

    FALSE is returned if the release operation failed.  TRUE is returned
    if the release operation succeeded.

    INVALID_VALUE is generated by AcquireKeyedMutexWin32EXT and
    ReleaseKeyedMutexWin32EXT if <memory> is not a valid memory object
    associated memory.

    INVALID_VALUE is generated by AcquireKeyedMutexWin32EXT and
    ReleaseKeyedMutexWin32EXT if the memory resource referred to by
    <memory> has no associated keyed mutex.

    INVALID_OPERATION is generated by AcquireKeyedMutexWin32EXT and
    ReleaseKeyedMutexWin32EXT if the acquire or release operation failed
    for operating-system-specific reasons.

None.

Revision 2, 2016-06-06 (James Jones)
    - Added extension numbers.
    - Marked complete.

Revision 1, 2017-03-31 (James Jones)
    - Initial draft.