added hardware querents

but some GPU utilities are TODO

quest/src/comm/communication.cpp

@@ -6,12 +6,31 @@
 #include "quest/include/modes.h"
 #include "quest/include/types.h"
 
+#include "quest/src/core/errors.hpp"
+
 #if ENABLE_DISTRIBUTION
     #include <mpi.h>
 #endif
 
 
 
+/*
+ * WARN ABOUT CUDA-AWARENESS
+ */
+
+#if ENABLE_DISTRIBUTION && ENABLE_GPU_ACCELERATION
+    #include <mpi-ext.h>
+
+    #ifndef MPIX_CUDA_AWARE_SUPPORT
+        #warning "Could not ascertain whether MPI is CUDA-aware, so we will assume it is not. This means inter-GPU communication will be slowly routed through the CPU/RAM."
+    #elif !MPIX_CUDA_AWARE_SUPPORT
+        #warning "MPI compiler is not CUDA-aware, so inter-GPU communication will be slowly routed through the CPU/RAM"
+    #endif
+
+#endif
+
+
+
 /*
  * MPI COMPLEX TYPE FLAG
  */
@@ -33,4 +52,88 @@
         #define MPI_QCOMP MPI_C_LONG_DOUBLE_COMPLEX
     #endif
 
-#endif
+#endif
+
+
+
+/*
+ * MPI ENVIRONMENT MANAGEMENT
+ * all of which is safely callable in non-distributed mode
+ */
+
+
+bool comm_isMpiCompiled() {
+    return (bool) ENABLE_DISTRIBUTION;
+}
+
+
+bool comm_isMpiGpuAware() {
+
+    // TODO: these checks may be OpenMPI specific, so that
+    // non-OpenMPI MPI compilers are always dismissed as
+    // not being CUDA-aware. Check e.g. MPICH method!
+
+    // definitely not GPU-aware if compiler declares it is not
+    #if defined(MPIX_CUDA_AWARE_SUPPORT) && ! MPIX_CUDA_AWARE_SUPPORT
+        return false;
+    #endif
+
+    // check CUDA-awareness at run-time if we know it's principally supported
+    #if defined(MPIX_CUDA_AWARE_SUPPORT)
+        return (bool) MPIX_Query_cuda_support();
+    #endif
+
+    // if we can't ascertain CUDA-awareness, just assume no to avoid seg-fault
+    return false;
+}
+
+
+void comm_init() {
+#if ENABLE_DISTRIBUTION
+    int isInit;
+    MPI_Initialized(&isInit);
+
+    // gracefully handle re-initialisation
+    if (isInit)
+        error_commAlreadyInit();
+
+    MPI_Init(NULL, NULL);
+#endif
+}
+
+
+void comm_end() {
+#if ENABLE_DISTRIBUTION
+    MPI_Barrier(MPI_COMM_WORLD);
+    MPI_Finalize();
+#endif
+}
+
+
+int comm_getRank() {
+#if ENABLE_DISTRIBUTION
+    int rank;
+    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+    return rank;
+#else
+    return 0;
+#endif
+}
+
+
+int comm_getNumNodes() {
+#if ENABLE_DISTRIBUTION
+    int numNodes;
+    MPI_Comm_size(MPI_COMM_WORLD, &numNodes);
+    return numNodes;
+#else
+    return 1;
+#endif
+}
+
+
+void comm_synch() {
+#if ENABLE_DISTRIBUTION
+    MPI_Barrier(MPI_COMM_WORLD);
+#endif
+}

quest/src/comm/communication.hpp

@@ -8,4 +8,24 @@
 
 
 
+/*
+ * MPI ENVIRONMENT MANAGEMENT
+ */
+
+bool comm_isMpiCompiled();
+
+bool comm_isMpiGpuAware();
+
+void comm_init();
+
+void comm_end();
+
+int comm_getRank();
+
+int comm_getNumNodes();
+
+void comm_synch();
+
+
+
 #endif // COMMUNICATION_HPP

quest/src/core/errors.cpp

@@ -49,4 +49,26 @@ void error_validationMessageVarNotSubstituted(std::string msg, std::string var)
 void error_validationMessageContainedUnsubstitutedVars(std::string msg) {
 
     raiseInternalError("User input validation failed and an error string was prepared. However, the message contained unexpected (and potentially ill-formed) unsubstituted variables. The message was:\n" + msg + "\n");
-}
+}
+
+
+
+/*
+ * COMMUNICATION ERRORS
+ */
+
+void error_commAlreadyInit() {
+
+    raiseInternalError("The MPI communication environment was attemptedly re-initialised, despite the QuEST environment already existing.");
+}
+
+
+
+/*
+ * GPU ERRORS
+ */
+
+void error_gpuQueriedButGpuNotCompiled() {
+
+    raiseInternalError("A function attempted to query GPU properties but QuEST was not compiled with GPU acceleration enabled.");
+}

quest/src/core/errors.hpp

@@ -24,4 +24,20 @@ void error_validationMessageContainedUnsubstitutedVars(std::string msg);
 
 
 
+/*
+ * COMMUNICATION ERRORS
+ */
+
+void error_commAlreadyInit();
+
+
+
+/*
+ * GPU ERRORS
+ */
+
+void error_gpuQueriedButGpuNotCompiled();
+
+
+
 #endif // ERRORS_HPP

quest/src/core/validation.cpp

@@ -4,6 +4,7 @@
  */
 
 #include "quest/src/core/errors.hpp"
+#include "quest/src/comm/communication.hpp"
 
 #include <iostream>
 #include <cstdlib>

quest/src/cpu/omp_subroutines.cpp

@@ -6,12 +6,60 @@
 #include "quest/include/modes.h"
 #include "quest/include/types.h"
 
+#include "quest/src/core/errors.hpp"
+
+
+#if ENABLE_MULTITHREADING && !defined(_OPENMP)
+    #error "Attempted to compile in multithreaded mode without enabling OpenMP."
+#endif
+
+
 #if ENABLE_MULTITHREADING
     #include <omp.h>
 #endif
 
 
-// inform OpenMP how to reduce qcomp instances (except on MSVC compilers)
+
+/*
+ * ENABLE OPENMP REDUCTION OF qcomp (except on MSVC compilers)
+ */
+
 #if defined(ENABLE_MULTITHREADING) && !defined(_MSC_VER)
      #pragma omp declare reduction(+ : qcomp : omp_out += omp_in ) initializer( omp_priv = omp_orig )
-#endif
+#endif
+
+
+
+/*
+ * OPENMP CONFIG
+ */
+
+
+bool cpu_isOpenmpCompiled() {
+    return (bool) ENABLE_MULTITHREADING;
+}
+
+
+int cpu_getCurrentNumThreads() {
+#if ENABLE_MULTITHREADING
+    int n = -1;
+
+    #pragma omp parallel shared(n)
+    n = omp_get_num_threads();
+
+    return n;
+#else
+    error_cpuThreadsQueriedButEnvNotMultithreaded();
+    return -1;
+#endif
+}
+
+
+int cpu_getNumOpenmpProcessors() {
+#if ENABLE_MULTITHREADING
+    return omp_get_num_procs();
+#else
+    error_cpuThreadsQueriedButEnvNotMultithreaded();
+    return -1;
+#endif
+}

quest/src/cpu/omp_subroutines.hpp

@@ -7,4 +7,16 @@
 
 
 
+/*
+ * OPENMP CONFIG
+ */
+
+bool cpu_isOpenmpCompiled();
+
+int cpu_getCurrentNumThreads();
+
+int cpu_getNumOpenmpProcessors();
+
+
+
 #endif // OMP_SUBROUTINES_HPP