Developing and Porting C and C++ Applications on AIX

9.7. Synchronization constructs

Synchronization refers to the time order in which threads access shared or global variables. Because several parallel threads may need to access or update the same shared variable at about the same time, explicit control of synchronization is often required. A program with faulty synchronization may compile and run without incident, but will produce incorrect results.

OpenMP provides a variety of synchronization constructs, explained in the following sections, that control how the execution of each thread proceeds relative to other team threads:

• Section 9.7.1, “master construct” on page 349

• Section 9.7.2, “critical construct” on page 349

• Section 9.7.3, “barrier directive” on page 350

• Section 9.7.4, “atomic construct” ...