handle non commutative case for scan/exscan

[simgrid.git] / src / smpi / smpi_base.c

diff --git a/src/smpi/smpi_base.c b/src/smpi/smpi_base.c
index 73fe79a..ec16dbe 100644 (file)
--- a/src/smpi/smpi_base.c
+++ b/src/smpi/smpi_base.c
@@ -1247,7 +1247,7 @@ void smpi_mpi_allreduce(void *sendbuf, void *recvbuf, int count,
 void smpi_mpi_scan(void *sendbuf, void *recvbuf, int count,
                    MPI_Datatype datatype, MPI_Op op, MPI_Comm comm)
 {
-  int system_tag = 888;
+  int system_tag = -888;
   int rank, size, other, index;
   MPI_Aint lb = 0, dataext = 0;
   MPI_Request *requests;
@@ -1282,14 +1282,94 @@ void smpi_mpi_scan(void *sendbuf, void *recvbuf, int count,
   }
   // Wait for completion of all comms.
   smpi_mpi_startall(size - 1, requests);
-  for(other = 0; other < size - 1; other++) {
-    index = smpi_mpi_waitany(size - 1, requests, MPI_STATUS_IGNORE);
-    if(index == MPI_UNDEFINED) {
-      break;
+
+  if(smpi_op_is_commute(op)){
+    for(other = 0; other < size - 1; other++) {
+      index = smpi_mpi_waitany(size - 1, requests, MPI_STATUS_IGNORE);
+      if(index == MPI_UNDEFINED) {
+        break;
+      }
+      if(index < rank) {
+        // #Request is below rank: it's a irecv
+        smpi_op_apply(op, tmpbufs[index], recvbuf, &count, &datatype);
+      }
     }
-    if(index < rank) {
-      // #Request is below rank: it's a irecv
-      smpi_op_apply(op, tmpbufs[index], recvbuf, &count, &datatype);
+  }else{
+    //non commutative case, wait in order
+    for(other = 0; other < size - 1; other++) {
+      smpi_mpi_wait(&(requests[other]), MPI_STATUS_IGNORE);
+      if(index < rank) {
+        smpi_op_apply(op, tmpbufs[other], recvbuf, &count, &datatype);
+      }
+    }
+  }
+  for(index = 0; index < rank; index++) {
+    xbt_free(tmpbufs[index]);
+  }
+  xbt_free(tmpbufs);
+  xbt_free(requests);
+}
+
+void smpi_mpi_exscan(void *sendbuf, void *recvbuf, int count,
+                   MPI_Datatype datatype, MPI_Op op, MPI_Comm comm)
+{
+  int system_tag = -888;
+  int rank, size, other, index;
+  MPI_Aint lb = 0, dataext = 0;
+  MPI_Request *requests;
+  void **tmpbufs;
+  int recvbuf_is_empty=1;
+  rank = smpi_comm_rank(comm);
+  size = smpi_comm_size(comm);
+
+  // FIXME: check for errors
+  smpi_datatype_extent(datatype, &lb, &dataext);
+
+  // Send/Recv buffers to/from others;
+  requests = xbt_new(MPI_Request, size - 1);
+  tmpbufs = xbt_new(void *, rank);
+  index = 0;
+  for(other = 0; other < rank; other++) {
+    // FIXME: possibly overkill we we have contiguous/noncontiguous data
+    // mapping...
+    tmpbufs[index] = xbt_malloc(count * dataext);
+    requests[index] =
+      smpi_irecv_init(tmpbufs[index], count, datatype, other, system_tag,
+                      comm);
+    index++;
+  }
+  for(other = rank + 1; other < size; other++) {
+    requests[index] =
+      smpi_isend_init(sendbuf, count, datatype, other, system_tag, comm);
+    index++;
+  }
+  // Wait for completion of all comms.
+  smpi_mpi_startall(size - 1, requests);
+  if(smpi_op_is_commute(op)){
+    for(other = 0; other < size - 1; other++) {
+      index = smpi_mpi_waitany(size - 1, requests, MPI_STATUS_IGNORE);
+      if(index == MPI_UNDEFINED) {
+        break;
+      }
+      if(index < rank) {
+        if(recvbuf_is_empty){
+          smpi_datatype_copy(tmpbufs[index], count, datatype, recvbuf, count, datatype);
+          recvbuf_is_empty=0;
+        }else
+        // #Request is below rank: it's a irecv
+        smpi_op_apply(op, tmpbufs[index], recvbuf, &count, &datatype);
+      }
+    }
+  }else{
+    //non commutative case, wait in order
+    for(other = 0; other < size - 1; other++) {
+      smpi_mpi_wait(&(requests[other]), MPI_STATUS_IGNORE);
+      if(index < rank) {
+          if(recvbuf_is_empty){
+            smpi_datatype_copy(tmpbufs[index], count, datatype, recvbuf, count, datatype);
+            recvbuf_is_empty=0;
+          }else smpi_op_apply(op, tmpbufs[other], recvbuf, &count, &datatype);
+      }
     }
   }
   for(index = 0; index < rank; index++) {