Remove dummy MPI_COMM_WORLD altogether

Author: Alessandro Gastaldi

Common/include/parallelization/mpi_structure.cpp

@@ -27,9 +27,17 @@
 
 #include "mpi_structure.hpp"
 
+
+/* Initialise the MPI Communicator Rank and Size */
 int CBaseMPIWrapper::Rank = 0;
 int CBaseMPIWrapper::Size = 1;
+
+/* Set the default MPI Communicator */
+#ifdef HAVE_MPI
 CBaseMPIWrapper::Comm CBaseMPIWrapper::currentComm = MPI_COMM_WORLD;
+#else
+CBaseMPIWrapper::Comm CBaseMPIWrapper::currentComm = 0;  // dummy value
+#endif
 
 #ifdef HAVE_MPI
 int  CBaseMPIWrapper::MinRankError;

Common/include/parallelization/mpi_structure.hpp

@@ -467,7 +467,6 @@ class CMediMPIWrapper : public CBaseMPIWrapper {
 
 #else  // HAVE_MPI
 
-#define MPI_COMM_WORLD 0
 #define MPI_UNSIGNED_LONG 1
 #define MPI_LONG 2
 #define MPI_UNSIGNED_SHORT 3

SU2_CFD/include/solvers/CFVMFlowSolverBase.hpp

@@ -458,10 +458,10 @@ class CFVMFlowSolverBase : public CSolver {
     SU2_OMP_MASTER
     if (config->GetComm_Level() == COMM_FULL) {
       su2double rbuf_time;
-      SU2_MPI::Allreduce(&Min_Delta_Time, &rbuf_time, 1, MPI_DOUBLE, MPI_MIN, MPI_COMM_WORLD);
+      SU2_MPI::Allreduce(&Min_Delta_Time, &rbuf_time, 1, MPI_DOUBLE, MPI_MIN, SU2_MPI::GetComm());
       Min_Delta_Time = rbuf_time;
 
-      SU2_MPI::Allreduce(&Max_Delta_Time, &rbuf_time, 1, MPI_DOUBLE, MPI_MAX, MPI_COMM_WORLD);
+      SU2_MPI::Allreduce(&Max_Delta_Time, &rbuf_time, 1, MPI_DOUBLE, MPI_MAX, SU2_MPI::GetComm());
       Max_Delta_Time = rbuf_time;
     }
     SU2_OMP_BARRIER
@@ -513,7 +513,7 @@ class CFVMFlowSolverBase : public CSolver {
 
       SU2_OMP_MASTER
       {
-        SU2_MPI::Allreduce(&Global_Delta_UnstTimeND, &glbDtND, 1, MPI_DOUBLE, MPI_MIN, MPI_COMM_WORLD);
+        SU2_MPI::Allreduce(&Global_Delta_UnstTimeND, &glbDtND, 1, MPI_DOUBLE, MPI_MIN, SU2_MPI::GetComm());
         Global_Delta_UnstTimeND = glbDtND;
 
         config->SetDelta_UnstTimeND(Global_Delta_UnstTimeND);
@@ -1068,8 +1068,8 @@ class CFVMFlowSolverBase : public CSolver {
         su2double MyOmega_Max = Omega_Max;
         su2double MyStrainMag_Max = StrainMag_Max;
 
-        SU2_MPI::Allreduce(&MyStrainMag_Max, &StrainMag_Max, 1, MPI_DOUBLE, MPI_MAX, MPI_COMM_WORLD);
-        SU2_MPI::Allreduce(&MyOmega_Max, &Omega_Max, 1, MPI_DOUBLE, MPI_MAX, MPI_COMM_WORLD);
+        SU2_MPI::Allreduce(&MyStrainMag_Max, &StrainMag_Max, 1, MPI_DOUBLE, MPI_MAX, SU2_MPI::GetComm());
+        SU2_MPI::Allreduce(&MyOmega_Max, &Omega_Max, 1, MPI_DOUBLE, MPI_MAX, SU2_MPI::GetComm());
       }
       SU2_OMP_BARRIER
     }

SU2_CFD/src/SU2_CFD.cpp

@@ -67,7 +67,7 @@ int main(int argc, char *argv[]) {
 #else
   SU2_MPI::Init(&argc, &argv);
 #endif
-  SU2_Comm MPICommunicator(MPI_COMM_WORLD);
+  SU2_MPI::Comm MPICommunicator = SU2_MPI::GetComm();
 
   /*--- Uncomment the following line if runtime NaN catching is desired. ---*/
   // feenableexcept(FE_INVALID | FE_OVERFLOW);

SU2_CFD/src/solvers/CIncEulerSolver.cpp

@@ -835,7 +835,7 @@ void CIncEulerSolver::CommonPreprocessing(CGeometry *geometry, CSolver **solver_
     SU2_OMP_MASTER
     {
       unsigned long tmp = ErrorCounter;
-      SU2_MPI::Allreduce(&tmp, &ErrorCounter, 1, MPI_UNSIGNED_LONG, MPI_SUM, MPI_COMM_WORLD);
+      SU2_MPI::Allreduce(&tmp, &ErrorCounter, 1, MPI_UNSIGNED_LONG, MPI_SUM, SU2_MPI::GetComm());
       config->SetNonphysical_Points(ErrorCounter);
     }
     SU2_OMP_BARRIER
@@ -1660,7 +1660,7 @@ void CIncEulerSolver::SetBeta_Parameter(CGeometry *geometry, CSolver **solver_co
 
     SU2_OMP_MASTER {
       maxVel2 = MaxVel2;
-      SU2_MPI::Allreduce(&maxVel2, &MaxVel2, 1, MPI_DOUBLE, MPI_MAX, MPI_COMM_WORLD);
+      SU2_MPI::Allreduce(&maxVel2, &MaxVel2, 1, MPI_DOUBLE, MPI_MAX, SU2_MPI::GetComm());
 
       config->SetMax_Vel2(max(1e-10, MaxVel2));
     }

SU2_DEF/src/SU2_DEF.cpp

@@ -45,7 +45,7 @@ int main(int argc, char *argv[]) {
 #else
   SU2_MPI::Init(&argc, &argv);
 #endif
-  SU2_MPI::Comm MPICommunicator(MPI_COMM_WORLD);
+  SU2_MPI::Comm MPICommunicator = SU2_MPI::GetComm();
 
   rank = SU2_MPI::GetRank();
   size = SU2_MPI::GetSize();

SU2_DOT/src/SU2_DOT.cpp

@@ -44,7 +44,7 @@ int main(int argc, char *argv[]) {
 #else
   SU2_MPI::Init(&argc, &argv);
 #endif
-  SU2_MPI::Comm MPICommunicator(MPI_COMM_WORLD);
+  SU2_MPI::Comm MPICommunicator = SU2_MPI::GetComm();
 
   const int rank = SU2_MPI::GetRank();
   const int size = SU2_MPI::GetSize();
@@ -644,7 +644,7 @@ void SetProjection_FD(CGeometry *geometry, CConfig *config, CSurfaceMovement *su
         }
       }
 
-      SU2_MPI::Allreduce(&my_Gradient, &localGradient, 1, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD);
+      SU2_MPI::Allreduce(&my_Gradient, &localGradient, 1, MPI_DOUBLE, MPI_SUM, SU2_MPI::GetComm());
       Gradient[iDV][0] += localGradient;
     }
   }
@@ -770,7 +770,7 @@ void SetProjection_AD(CGeometry *geometry, CConfig *config, CSurfaceMovement *su
     for (iDV_Value = 0; iDV_Value < nDV_Value; iDV_Value++){
       DV_Value = config->GetDV_Value(iDV, iDV_Value);
       my_Gradient = SU2_TYPE::GetDerivative(DV_Value);
-      SU2_MPI::Allreduce(&my_Gradient, &localGradient, 1, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD);
+      SU2_MPI::Allreduce(&my_Gradient, &localGradient, 1, MPI_DOUBLE, MPI_SUM, SU2_MPI::GetComm());
 
       /*--- Angle of Attack design variable (this is different,
        the value comes form the input file) ---*/

SU2_GEO/src/SU2_GEO.cpp

@@ -59,7 +59,7 @@ int main(int argc, char *argv[]) {
   /*--- MPI initialization ---*/
 
   SU2_MPI::Init(&argc,&argv);
-  SU2_MPI::Comm MPICommunicator(MPI_COMM_WORLD);
+  SU2_MPI::Comm MPICommunicator = SU2_MPI::GetComm();
 
   rank = SU2_MPI::GetRank();
   size = SU2_MPI::GetSize();

SU2_SOL/src/SU2_SOL.cpp

@@ -40,7 +40,7 @@ int main(int argc, char *argv[]) {
   /*--- MPI initialization ---*/
 
   SU2_MPI::Init(&argc,&argv);
-  SU2_MPI::Comm MPICommunicator(MPI_COMM_WORLD);
+  SU2_MPI::Comm MPICommunicator = SU2_MPI::GetComm();
 
   const int rank = SU2_MPI::GetRank();
   const int size = SU2_MPI::GetSize();

UnitTests/test_driver.cpp

@@ -43,7 +43,7 @@ int main(int argc, char *argv[]) {
 #else
   SU2_MPI::Init(&argc, &argv);
 #endif
-  SU2_Comm MPICommunicator(MPI_COMM_WORLD);
+  SU2_MPI::Comm MPICommunicator = SU2_MPI::GetComm();
 
   /*--- Run the test driver supplied by Catch ---*/
   int result = Catch::Session().run(argc, argv);