working with mpi compile on main, initialising MPI on main and calling mpi functions on library

build.bat

@@ -1,4 +1,4 @@
-@rem @echo off
+@echo off
 setlocal
 
 @rem I rely on environment variables here.
@@ -22,7 +22,7 @@ set CudaLibPaths=-L"%CUDA_PATH%\lib\x64" -L"%CUDSS_PATH%\lib\12"
 
 set LibraryLinks=-lcudss -lcudart
 
-nvcc -v -c -o build/%commLayerSource%.obj src/%commLayerSource%.cu ^
+nvcc -c -o build/%commLayerSource%.obj src/%commLayerSource%.cu ^
     -arch=%nvccArch% ^
      %CudaIncludes% %OtherIncludes% %MPIIncludes% %CudaLibPaths% %MPILibPath% ^
     %LibraryLinks% ^
@@ -48,8 +48,8 @@ if %ERRORLEVEL% NEQ 0 (
 
 nvcc -o build/%mainSource% src/%mainSource%.cu ^
     -arch=%nvccArch% ^
-     %CudaIncludes% %OtherIncludes% %CudaLibPaths% ^
+     %CudaIncludes% %OtherIncludes% %CudaLibPaths% %MPIIncludes% %MPILibPath% ^
-    -lcudss -lcudart ^
+    -lcudss -lcudart -lmsmpi ^
     %IgnoreWarnings% ^
     -Xcompiler %ExeXcompilerFlags%
 

src/commlayer.cu

@@ -3,6 +3,8 @@
 
 #include <mpi.h>
 
+#include "cudss.h"
+
 #define __CSCUDSS_EXPORT extern "C" __declspec(dllexport)
 
 
@@ -18,10 +20,7 @@ __CSCUDSS_EXPORT int cudssCommSize(void *comm, int *size) {
 
 
 
-__CSCUDSS_EXPORT int libraryMain() {
+__CSCUDSS_EXPORT int libraryMain(void) {
-
-  MPI_Init(0,0);
-  std::cout << "HELLO LIBRARY" << std::endl;
 
   int rank;
   int size;
@@ -29,9 +28,8 @@ __CSCUDSS_EXPORT int libraryMain() {
   cudssCommRank(&Comm, &rank);
   cudssCommSize(&Comm, &size);
 
-  std::cout << "Rank: " << rank << ", size: " << size << std::endl;
+  std::cout << "Entered library for Rank: " << rank << ", size: " << size << std::endl;
 
-  MPI_Finalize();
   return 0;
 
 }

src/main.cu

@@ -6,13 +6,17 @@
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 
+#include <mpi.h>
+
 #include "util.h"
 
 /* ============================================================================
  * Version Information
  * ============================================================================ */
 
-void printCudaVersion(void) {
+void printCudaVersion(int rank) {
+    if(rank !=0) return;
+
     int runtimeVersion = 0;
     int driverVersion = 0;
     
@@ -29,7 +33,9 @@ void printCudaVersion(void) {
     LOG("CUDA Driver Version:  %d.%d", driverMajor, driverMinor);
 }
 
-void printCudssVersion(void) {
+void printCudssVersion(int rank) {
+    if(rank !=0) return;
+
     int major = 0;
     int minor = 0;
     int patch = 0;
@@ -41,7 +47,9 @@ void printCudssVersion(void) {
     LOG("cuDSS Version: %d.%d.%d", major, minor, patch);
 }
 
-void printDeviceInfo(void) {
+void printDeviceInfo(int rank) {
+    if(rank !=0) return;
+
     int deviceCount = 0;
     CUDA_CHECK(cudaGetDeviceCount(&deviceCount));
     
@@ -67,13 +75,22 @@ void printDeviceInfo(void) {
 using libraryMain = int(*)();
 
 int main(int argc, char **argv) {
-    LOG("cuDSS Test Program");
+
-    LOG("==================");
+    MPI_Init(0,0);
+    int rank;
+    int size;
+    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+    MPI_Comm_size(MPI_COMM_WORLD, &size);
+
+    if(rank == 0) {
+      LOG("cuDSS Test Program");
+      LOG("==================");
+    }
 
     /* Print version information */
-    printCudaVersion();
+    printCudaVersion(rank);
-    printCudssVersion();
+    printCudssVersion(rank);
-    printDeviceInfo();
+    printDeviceInfo(rank);
     
     HMODULE hLib = LoadLibraryA("commlayer.dll");
     if (!hLib) {
@@ -92,12 +109,18 @@ int main(int argc, char **argv) {
     /* Initialize cuDSS */
     cudssHandle_t handle = NULL;
     CUDSS_CHECK(cudssCreate(&handle));
-    LOG("cuDSS handle created successfully");
+    if(rank == 0) {
-       
+      LOG("cuDSS handle created successfully");
+    }
     /* Cleanup */
     CUDSS_CHECK(cudssDestroy(handle));
-    LOG("cuDSS handle destroyed");
+    if(rank == 0) {
+      LOG("cuDSS handle destroyed");
+    }
 
-    LOG("Done.");
+    MPI_Finalize();
+    if(rank == 0) {
+      LOG("Done.");
+    }
     return 0;
 }