threadsOMP.cpp

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 *       - Pierre-Henri WUILLEMIN(_at_LIP6)                                 *
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#include <agrum/agrum.h>
 
#include <agrum/base/core/threads/threadsOMP.h>
 
// include the inlined functions if necessary
#ifdef GUM_NO_INLINE
#  include <agrum/base/core/threads/threadsOMP_inl.h>
#endif /* GUM_NO_INLINE */
 
namespace gum {
 
  namespace threadsOMP {
 
    // the number of threads used the next time we enter into a parallel region
    static unsigned int _nb_threads_{getMaxNumberOfThreads()};
 
    // returns the max number of threads used by default when entering the
    // next parallel region
    unsigned int getNumberOfThreads() { return _nb_threads_; }
 
    // Set the max number of threads to be used.
    void setNumberOfThreads(unsigned int number) {
      if (number == 0) number = 1;
#ifdef _OPENMP
      omp_set_num_threads(number);
      _nb_threads_ = number;
#else
      if (number != 1) {
        GUM_ERROR(OperationNotAllowed,
                  "openMP was not enabled at compilation (or "
                  "you asked for 0 threads !)");
      }
#endif
    }
 
  }   // namespace threadsOMP
 
}   // namespace gum