X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/70ed180f3ce3495678d048e9e396ef5eb65a6a99..91bb8b44ef09735fc79f40a3d9eeb69456a46909:/src/smpi/smpi_comm.c

diff --git a/src/smpi/smpi_comm.c b/src/smpi/smpi_comm.c
index 59aa85d390..8f02e2e0ae 100644
--- a/src/smpi/smpi_comm.c
+++ b/src/smpi/smpi_comm.c
@@ -1,34 +1,171 @@
+/* Copyright (c) 2010-2013. The SimGrid Team.
+ * All rights reserved.                                                     */
+
+/* This program is free software; you can redistribute it and/or modify it
+  * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include <stdlib.h>
+
 #include "private.h"
+#include "smpi_mpi_dt_private.h"
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(smpi_comm, smpi,
                                 "Logging specific to SMPI (comm)");
 
 typedef struct s_smpi_mpi_communicator {
   MPI_Group group;
+  int refcount;
 } s_smpi_mpi_communicator_t;
 
-MPI_Comm smpi_comm_new(MPI_Group group) {
+static int smpi_compare_rankmap(const void *a, const void *b)
+{
+  const int* x = (const int*)a;
+  const int* y = (const int*)b;
+
+  if (x[1] < y[1]) {
+    return -1;
+  }
+  if (x[1] == y[1]) {
+    if (x[0] < y[0]) {
+      return -1;
+    }
+    if (x[0] == y[0]) {
+      return 0;
+    }
+    return 1;
+  }
+  return 1;
+}
+
+MPI_Comm smpi_comm_new(MPI_Group group)
+{
   MPI_Comm comm;
 
   comm = xbt_new(s_smpi_mpi_communicator_t, 1);
   comm->group = group;
   smpi_group_use(comm->group);
+  comm->refcount=1;
   return comm;
 }
 
-void smpi_comm_destroy(MPI_Comm comm) {
-  smpi_group_destroy(comm->group);
-  xbt_free(comm);
+void smpi_comm_destroy(MPI_Comm comm)
+{
+  smpi_group_unuse(comm->group);
+  smpi_comm_unuse(comm);
 }
 
-MPI_Group smpi_comm_group(MPI_Comm comm) {
+MPI_Group smpi_comm_group(MPI_Comm comm)
+{
   return comm->group;
 }
 
-int smpi_comm_size(MPI_Comm comm) {
+int smpi_comm_size(MPI_Comm comm)
+{
   return smpi_group_size(smpi_comm_group(comm));
 }
 
-int smpi_comm_rank(MPI_Comm comm) {
+int smpi_comm_rank(MPI_Comm comm)
+{
   return smpi_group_rank(smpi_comm_group(comm), smpi_process_index());
 }
+
+void smpi_comm_get_name (MPI_Comm comm, char* name, int* len)
+{
+  if(comm == MPI_COMM_WORLD) {
+    strcpy(name, "WORLD");
+    *len = 5;
+  } else {
+    *len = snprintf(name, MPI_MAX_NAME_STRING, "%p", comm);
+  }
+}
+
+MPI_Comm smpi_comm_split(MPI_Comm comm, int color, int key)
+{
+  int system_tag = 123;
+  int index, rank, size, i, j, count, reqs;
+  int* sendbuf;
+  int* recvbuf;
+  int* rankmap;
+  MPI_Group group, group_root, group_out;
+  MPI_Request* requests;
+
+  group_root = group_out = NULL;
+  group = smpi_comm_group(comm);
+  rank = smpi_comm_rank(comm);
+  size = smpi_comm_size(comm);
+  /* Gather all colors and keys on rank 0 */
+  sendbuf = xbt_new(int, 2);
+  sendbuf[0] = color;
+  sendbuf[1] = key;
+  if(rank == 0) {
+    recvbuf = xbt_new(int, 2 * size);
+  } else {
+    recvbuf = NULL;
+  }
+  smpi_mpi_gather(sendbuf, 2, MPI_INT, recvbuf, 2, MPI_INT, 0, comm);
+  xbt_free(sendbuf);
+  /* Do the actual job */
+  if(rank == 0) {
+    rankmap = xbt_new(int, 2 * size);
+    for(i = 0; i < size; i++) {
+      if(recvbuf[2 * i] == MPI_UNDEFINED) {
+        continue;
+      }
+      count = 0;
+      for(j = i + 1; j < size; j++)  {
+        if(recvbuf[2 * i] == recvbuf[2 * j]) {
+          recvbuf[2 * j] = MPI_UNDEFINED;
+          rankmap[2 * count] = j;
+          rankmap[2 * count + 1] = recvbuf[2 * j + 1];
+          count++;
+        }
+      }
+      /* Add self in the group */
+      recvbuf[2 * i] = MPI_UNDEFINED;
+      rankmap[2 * count] = i;
+      rankmap[2 * count + 1] = recvbuf[2 * i + 1];
+      count++;
+      qsort(rankmap, count, 2 * sizeof(int), &smpi_compare_rankmap);
+      group_out = smpi_group_new(count);
+      if(i == 0) {
+        group_root = group_out; /* Save root's group */
+      }
+      for(j = 0; j < count; j++) {
+        //increment refcounter in order to avoid freeing the group too quick before copy
+        index = smpi_group_index(group, rankmap[2 * j]);
+        smpi_group_set_mapping(group_out, index, j);
+      }
+      requests = xbt_new(MPI_Request, count);
+      reqs = 0;
+      for(j = 0; j < count; j++) {
+        if(rankmap[2 * j] != 0) {
+          requests[reqs] = smpi_isend_init(&group_out, 1, MPI_PTR, rankmap[2 * j], system_tag, comm);
+          reqs++;
+        }
+      }
+      smpi_mpi_startall(reqs, requests);
+      smpi_mpi_waitall(reqs, requests, MPI_STATUS_IGNORE);
+      xbt_free(requests);
+    }
+    xbt_free(recvbuf);
+    group_out = group_root; /* exit with root's group */
+  } else {
+    if(color != MPI_UNDEFINED) {
+      smpi_mpi_recv(&group_out, 1, MPI_PTR, 0, system_tag, comm, MPI_STATUS_IGNORE);
+      if(group_out){
+        group_out=smpi_group_copy(group_out);
+      }
+    } /* otherwise, exit with group_out == NULL */
+  }
+  return group_out ? smpi_comm_new(group_out) : MPI_COMM_NULL;
+}
+
+void smpi_comm_use(MPI_Comm comm){
+  comm->refcount++;
+}
+
+void smpi_comm_unuse(MPI_Comm comm){
+  comm->refcount--;
+  if(comm->refcount==0)
+    xbt_free(comm);
+}