Add collectives for allgather, allreduce, bcast and reduce

[simgrid.git] / src / smpi / colls / bcast-flattree-pipeline.c

diff --git a/src/smpi/colls/bcast-flattree-pipeline.c b/src/smpi/colls/bcast-flattree-pipeline.c
new file mode 100644 (file)
index 0000000..5212032
--- /dev/null
+++ b/src/smpi/colls/bcast-flattree-pipeline.c
@@ -0,0 +1,54 @@
+#include "colls.h"
+
+int flattree_segment_in_byte = 8192;
+
+int
+smpi_coll_tuned_bcast_flattree_pipeline(void *buff, int count,
+                                        MPI_Datatype data_type, int root,
+                                        MPI_Comm comm)
+{
+  int i, j, rank, num_procs;
+  int tag = 1;
+
+  MPI_Aint extent;
+  MPI_Type_extent(data_type, &extent);
+
+  int segment = flattree_segment_in_byte / extent;
+  int pipe_length = count / segment;
+  int increment = segment * extent;
+
+  MPI_Comm_rank(comm, &rank);
+  MPI_Comm_size(comm, &num_procs);
+
+  MPI_Request *request_array;
+  MPI_Status *status_array;
+
+  request_array = (MPI_Request *) malloc(pipe_length * sizeof(MPI_Request));
+  status_array = (MPI_Status *) malloc(pipe_length * sizeof(MPI_Status));
+
+  if (rank != root) {
+    for (i = 0; i < pipe_length; i++) {
+      MPI_Irecv((char *)buff + (i * increment), segment, data_type, root, tag, comm,
+                &request_array[i]);
+    }
+    MPI_Waitall(pipe_length, request_array, status_array);
+  }
+
+  else {
+    // Root sends data to all others
+    for (j = 0; j < num_procs; j++) {
+      if (j == rank)
+        continue;
+      else {
+        for (i = 0; i < pipe_length; i++) {
+          MPI_Send((char *)buff + (i * increment), segment, data_type, j, tag, comm);
+        }
+      }
+    }
+
+  }
+
+  free(request_array);
+  free(status_array);
+  return MPI_SUCCESS;
+}