Description
The OpenCL C programming language implements a subset of the C11 atomics (refer to section 7.17 of the C11 specification) and synchronization operations. These operations play a special role in making assignments in one work-item visible to another. A synchronization operation on one or more memory locations is either an acquire operation, a release operation, or both an acquire and release operation. (The C11 consume operation is not supported.) A synchronization operation without an associated memory location is a fence and can be either an acquire fence, a release fence or both an acquire and release fence. In addition, there are relaxed atomic operations, which are not synchronization operations, and atomic read-modify-write operations which have special characteristics
The enumerated type memory_order specifies the detailed regular (non-atomic) memory synchronization operations as defined in section 5.1.2.4 of the C11 specification and may provide for operation ordering. Its enumeration constants are as follows:
memory_order_relaxed
memory_order_acquire
memory_order_release
memory_order_acq_rel
memory_order_seq_cst
The memory_order can be used when performing atomic operations to global or local memory.
Copyright © 2007-2013 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.