X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/0f5e8daaa6e9f74521068aa75837200bcd182ea6..8b9fbe95d804fdef03fd9e09419d568dddcbec3f:/src/smpi/smpi_base.c

diff --git a/src/smpi/smpi_base.c b/src/smpi/smpi_base.c
index b032ec7d4c..9ff9da7e0a 100644
--- a/src/smpi/smpi_base.c
+++ b/src/smpi/smpi_base.c
@@ -6,43 +6,32 @@
 
 #include "private.h"
 #include "xbt/time.h"
+#include "mc/mc.h"
+#include "xbt/replay.h"
+#include <errno.h>
+#include "surf/surf.h"
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(smpi_base, smpi,
                                 "Logging specific to SMPI (base)");
-XBT_LOG_EXTERNAL_CATEGORY(smpi_base);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_bench);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_kernel);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_mpi);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_mpi_dt);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_coll);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_receiver);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_sender);
-XBT_LOG_EXTERNAL_CATEGORY(smpi_util);
-
-void smpi_process_init(int *argc, char ***argv)
-{
-  int index;
-  smpi_process_data_t data;
-  smx_process_t proc;
-
-  proc = SIMIX_process_self();
-  index = atoi((*argv)[1]);
-  data = smpi_process_remote_data(index);
-  SIMIX_process_set_data(proc, data);
-  if (*argc > 2) {
-    free((*argv)[1]);
-    memmove(&(*argv)[1], &(*argv)[2], sizeof(char *) * (*argc - 2));
-    (*argv)[(*argc) - 1] = NULL;
-  }
-  (*argc)--;
-  DEBUG2("<%d> New process in the game: %p", index, proc);
+
+static int match_recv(void* a, void* b, smx_action_t ignored) {
+   MPI_Request ref = (MPI_Request)a;
+   MPI_Request req = (MPI_Request)b;
+
+   xbt_assert(ref, "Cannot match recv against null reference");
+   xbt_assert(req, "Cannot match recv against null request");
+   return (ref->src == MPI_ANY_SOURCE || req->src == ref->src)
+          && (ref->tag == MPI_ANY_TAG || req->tag == ref->tag);
 }
 
-void smpi_process_destroy(void)
-{
-  int index = smpi_process_index();
+static int match_send(void* a, void* b,smx_action_t ignored) {
+   MPI_Request ref = (MPI_Request)a;
+   MPI_Request req = (MPI_Request)b;
 
-  DEBUG1("<%d> Process left the game", index);
+   xbt_assert(ref, "Cannot match send against null reference");
+   xbt_assert(req, "Cannot match send against null request");
+   return (req->src == MPI_ANY_SOURCE || req->src == ref->src)
+          && (req->tag == MPI_ANY_TAG || req->tag == ref->tag);
 }
 
 static MPI_Request build_request(void *buf, int count,
@@ -53,15 +42,13 @@ static MPI_Request build_request(void *buf, int count,
 
   request = xbt_new(s_smpi_mpi_request_t, 1);
   request->buf = buf;
+  // FIXME: this will have to be changed to support non-contiguous datatypes
   request->size = smpi_datatype_size(datatype) * count;
   request->src = src;
   request->dst = dst;
   request->tag = tag;
   request->comm = comm;
-  request->rdv = NULL;
-  request->pair = NULL;
-  request->complete = 0;
-  request->match = MPI_REQUEST_NULL;
+  request->action = NULL;
   request->flags = flags;
 #ifdef HAVE_TRACING
   request->send = 0;
@@ -70,6 +57,41 @@ static MPI_Request build_request(void *buf, int count,
   return request;
 }
 
+void smpi_action_trace_run(char *path)
+{
+  char *name;
+  xbt_dynar_t todo;
+  xbt_dict_cursor_t cursor;
+
+  action_fp=NULL;
+  if (path) {
+    action_fp = fopen(path, "r");
+    xbt_assert(action_fp != NULL, "Cannot open %s: %s", path,
+                strerror(errno));
+  }
+
+  if (!xbt_dict_is_empty(action_queues)) {
+    XBT_WARN
+        ("Not all actions got consumed. If the simulation ended successfully (without deadlock), you may want to add new processes to your deployment file.");
+
+
+    xbt_dict_foreach(action_queues, cursor, name, todo) {
+      XBT_WARN("Still %lu actions for %s", xbt_dynar_length(todo), name);
+    }
+  }
+
+  if (path)
+    fclose(action_fp);
+  xbt_dict_free(&action_queues);
+  action_queues = xbt_dict_new_homogeneous(NULL);
+}
+
+static void smpi_mpi_request_free_voidp(void* request)
+{
+  MPI_Request req = request;
+  smpi_mpi_request_free(&req);
+}
+
 /* MPI Low level calls */
 MPI_Request smpi_mpi_send_init(void *buf, int count, MPI_Datatype datatype,
                                int dst, int tag, MPI_Comm comm)
@@ -93,27 +115,67 @@ MPI_Request smpi_mpi_recv_init(void *buf, int count, MPI_Datatype datatype,
 
 void smpi_mpi_start(MPI_Request request)
 {
-  xbt_assert0(request->complete == 0,
-              "Cannot start a non-finished communication");
-  if ((request->flags & RECV) == RECV) {
-    smpi_process_post_recv(request);
+  smx_rdv_t mailbox;
+  int detached = 0;
+
+  xbt_assert(!request->action,
+              "Cannot (re)start a non-finished communication");
+  if(request->flags & RECV) {
     print_request("New recv", request);
-    request->pair =
-        SIMIX_network_irecv(request->rdv, request->buf, &request->size);
+    if (request->size < xbt_cfg_get_int(_surf_cfg_set, "smpi/async_small_thres"))
+    mailbox = smpi_process_mailbox_small();
+    else
+    mailbox = smpi_process_mailbox();
+
+    // FIXME: SIMIX does not yet support non-contiguous datatypes
+    request->action = simcall_comm_irecv(mailbox, request->buf, &request->size, &match_recv, request);
   } else {
-    smpi_process_post_send(request->comm, request);     // FIXME
     print_request("New send", request);
-    request->pair =
-        SIMIX_network_isend(request->rdv, request->size, -1.0,
-                            request->buf, request->size, NULL);
-  }
+
+    if (request->size < xbt_cfg_get_int(_surf_cfg_set, "smpi/async_small_thres")) { // eager mode => detached send (FIXME: this limit should be configurable)
+      mailbox = smpi_process_remote_mailbox_small(
+            smpi_group_index(smpi_comm_group(request->comm), request->dst));
+    }else{
+      XBT_DEBUG("Send request %p is not in the permanent receive mailbox (buf: %p)",request,request->buf);
+      mailbox = smpi_process_remote_mailbox(
+                  smpi_group_index(smpi_comm_group(request->comm), request->dst));
+    }
+    if (request->size < 64*1024 ) { //(FIXME: this limit should be configurable)
+      void *oldbuf = request->buf;
+      detached = 1;
+      request->buf = malloc(request->size);
+      memcpy(request->buf,oldbuf,request->size);
+      XBT_DEBUG("Send request %p is detached; buf %p copied into %p",request,oldbuf,request->buf);
+    }else{
+      XBT_DEBUG("Send request %p is not detached (buf: %p)",request,request->buf);
+      mailbox = smpi_process_remote_mailbox(
+                  smpi_group_index(smpi_comm_group(request->comm), request->dst));
+    }
+
+      request->action =
+      simcall_comm_isend(mailbox, request->size, -1.0,
+              request->buf, request->size,
+              &match_send,
+              &smpi_mpi_request_free_voidp, // how to free the userdata if a detached send fails
+              request,
+              // detach if msg size < eager/rdv switch limit
+              detached);
+
+  #ifdef HAVE_TRACING
+      /* FIXME: detached sends are not traceable (request->action == NULL) */
+      if (request->action)
+        simcall_set_category(request->action, TRACE_internal_smpi_get_category());
+  #endif
+
+    }
+
 }
 
 void smpi_mpi_startall(int count, MPI_Request * requests)
 {
-  int i;
+    int i;
 
-  for (i = 0; i < count; i++) {
+  for(i = 0; i < count; i++) {
     smpi_mpi_start(requests[i]);
   }
 }
@@ -173,13 +235,15 @@ void smpi_mpi_recv(void *buf, int count, MPI_Datatype datatype, int src,
   smpi_mpi_wait(&request, status);
 }
 
+
+
 void smpi_mpi_send(void *buf, int count, MPI_Datatype datatype, int dst,
                    int tag, MPI_Comm comm)
 {
-  MPI_Request request;
+	  MPI_Request request;
 
-  request = smpi_mpi_isend(buf, count, datatype, dst, tag, comm);
-  smpi_mpi_wait(&request, MPI_STATUS_IGNORE);
+	  request = smpi_mpi_isend(buf, count, datatype, dst, tag, comm);
+	  smpi_mpi_wait(&request, MPI_STATUS_IGNORE);
 }
 
 void smpi_mpi_sendrecv(void *sendbuf, int sendcount, MPI_Datatype sendtype,
@@ -196,7 +260,7 @@ void smpi_mpi_sendrecv(void *sendbuf, int sendcount, MPI_Datatype sendtype,
       smpi_irecv_init(recvbuf, recvcount, recvtype, src, recvtag, comm);
   smpi_mpi_startall(2, requests);
   smpi_mpi_waitall(2, requests, stats);
-  if (status != MPI_STATUS_IGNORE) {
+  if(status != MPI_STATUS_IGNORE) {
     // Copy receive status
     memcpy(status, &stats[1], sizeof(MPI_Status));
   }
@@ -209,60 +273,80 @@ int smpi_mpi_get_count(MPI_Status * status, MPI_Datatype datatype)
 
 static void finish_wait(MPI_Request * request, MPI_Status * status)
 {
-  if (status != MPI_STATUS_IGNORE) {
-    status->MPI_SOURCE = (*request)->src;
-    status->MPI_TAG = (*request)->tag;
+  MPI_Request req = *request;
+
+  if(status != MPI_STATUS_IGNORE) {
+    status->MPI_SOURCE = req->src;
+    status->MPI_TAG = req->tag;
     status->MPI_ERROR = MPI_SUCCESS;
-    status->count = SIMIX_communication_get_dst_buf_size((*request)->pair);
-  }
-  print_request("finishing wait", *request);
-  if ((*request)->complete == 1) {
-    SIMIX_rdv_destroy((*request)->rdv);
-  } else {
-    (*request)->match->complete = 1;
-    (*request)->match->match = MPI_REQUEST_NULL;
+    // FIXME: really this should just contain the count of receive-type blocks,
+    // right?
+    status->count = req->size;
   }
-  if (((*request)->flags & NON_PERSISTENT) == NON_PERSISTENT) {
+  print_request("Finishing", req);
+  if(req->flags & NON_PERSISTENT) {
     smpi_mpi_request_free(request);
   } else {
-    (*request)->rdv = NULL;
-    (*request)->pair = NULL;
+    req->action = NULL;
   }
 }
 
-int smpi_mpi_test(MPI_Request * request, MPI_Status * status)
-{
-  int flag = (*request)->complete;
+int smpi_mpi_test(MPI_Request * request, MPI_Status * status) {
+int flag;
 
-  if (flag) {
-    smpi_mpi_wait(request, status);
-  }
-  return flag;
+   if ((*request)->action == NULL)
+  flag = 1;
+   else 
+    flag = simcall_comm_test((*request)->action);
+   if(flag) {
+        smpi_mpi_wait(request, status);
+    }
+    return flag;
 }
 
 int smpi_mpi_testany(int count, MPI_Request requests[], int *index,
                      MPI_Status * status)
 {
-  int i, flag;
+  xbt_dynar_t comms;
+  int i, flag, size;
+  int* map;
 
   *index = MPI_UNDEFINED;
   flag = 0;
-  for (i = 0; i < count; i++) {
-    if (requests[i] != MPI_REQUEST_NULL && requests[i]->complete) {
-      smpi_mpi_wait(&requests[i], status);
-      *index = i;
-      flag = 1;
-      break;
+  if(count > 0) {
+    comms = xbt_dynar_new(sizeof(smx_action_t), NULL);
+    map = xbt_new(int, count);
+    size = 0;
+    for(i = 0; i < count; i++) {
+      if(requests[i]->action) {
+         xbt_dynar_push(comms, &requests[i]->action);
+         map[size] = i;
+         size++;
+      }
     }
+    if(size > 0) {
+      i = simcall_comm_testany(comms);
+      // FIXME: MPI_UNDEFINED or does SIMIX have a return code?
+      if(i != MPI_UNDEFINED) {
+        *index = map[i];
+        smpi_mpi_wait(&requests[*index], status);
+        flag = 1;
+      }
+    }
+    xbt_free(map);
+    xbt_dynar_free(&comms);
   }
   return flag;
 }
 
 void smpi_mpi_wait(MPI_Request * request, MPI_Status * status)
 {
-  print_request("wait", *request);
-  SIMIX_network_wait((*request)->pair, -1.0);
-  finish_wait(request, status);
+  print_request("Waiting", *request);
+  if ((*request)->action != NULL) { // this is not a detached send
+    simcall_comm_wait((*request)->action, -1.0);
+    finish_wait(request, status);
+  }
+  // FIXME for a detached send, finish_wait is not called:
 }
 
 int smpi_mpi_waitany(int count, MPI_Request requests[],
@@ -273,37 +357,32 @@ int smpi_mpi_waitany(int count, MPI_Request requests[],
   int *map;
 
   index = MPI_UNDEFINED;
-  if (count > 0) {
-    // First check for already completed requests
-    for (i = 0; i < count; i++) {
-      if (requests[i] != MPI_REQUEST_NULL && requests[i]->complete) {
-        index = i;
-        smpi_mpi_wait(&requests[index], status);
-        break;
+  if(count > 0) {
+    // Wait for a request to complete
+    comms = xbt_dynar_new(sizeof(smx_action_t), NULL);
+    map = xbt_new(int, count);
+    size = 0;
+    XBT_DEBUG("Wait for one of");
+    for(i = 0; i < count; i++) {
+      if((requests[i] != MPI_REQUEST_NULL) && (requests[i]->action != NULL)) {
+        print_request("Waiting any ", requests[i]);
+        xbt_dynar_push(comms, &requests[i]->action);
+        map[size] = i;
+        size++;
       }
     }
-    if (index == MPI_UNDEFINED) {
-      // Otherwise, wait for a request to complete
-      comms = xbt_dynar_new(sizeof(smx_comm_t), NULL);
-      map = xbt_new(int, count);
-      size = 0;
-      DEBUG0("Wait for one of");
-      for (i = 0; i < count; i++) {
-        if (requests[i] != MPI_REQUEST_NULL && requests[i]->complete == 0) {
-          print_request("   ", requests[i]);
-          xbt_dynar_push(comms, &requests[i]->pair);
-          map[size] = i;
-          size++;
-        }
-      }
-      if (size > 0) {
-        index = SIMIX_network_waitany(comms);
-        index = map[index];
+    if(size > 0) {
+      i = simcall_comm_waitany(comms);
+
+      // FIXME: MPI_UNDEFINED or does SIMIX have a return code?
+      if (i != MPI_UNDEFINED) {
+        index = map[i];
         finish_wait(&requests[index], status);
+
       }
-      xbt_free(map);
-      xbt_dynar_free(&comms);
     }
+    xbt_free(map);
+    xbt_dynar_free(&comms);
   }
   return index;
 }
@@ -311,39 +390,37 @@ int smpi_mpi_waitany(int count, MPI_Request requests[],
 void smpi_mpi_waitall(int count, MPI_Request requests[],
                       MPI_Status status[])
 {
-  int index;
+  int index, c;
   MPI_Status stat;
-
-  while (count > 0) {
-    index = smpi_mpi_waitany(count, requests, &stat);
-    if (index == MPI_UNDEFINED) {
-      break;
+  MPI_Status *pstat = status == MPI_STATUS_IGNORE ? MPI_STATUS_IGNORE : &stat;
+
+  for(c = 0; c < count; c++) {
+    if(MC_IS_ENABLED) {
+      smpi_mpi_wait(&requests[c], pstat);
+      index = c;
+    } else {
+      index = smpi_mpi_waitany(count, requests, pstat);
+      if(index == MPI_UNDEFINED) {
+        break;
+      }
     }
-    if (status != MPI_STATUS_IGNORE) {
-      memcpy(&status[index], &stat, sizeof(stat));
+    if(status != MPI_STATUS_IGNORE) {
+      memcpy(&status[index], pstat, sizeof(*pstat));
     }
-    // FIXME: check this -v
-    // Move the last request to the found position
-    requests[index] = requests[count - 1];
-    requests[count - 1] = MPI_REQUEST_NULL;
-    count--;
   }
 }
 
 int smpi_mpi_waitsome(int incount, MPI_Request requests[], int *indices,
                       MPI_Status status[])
 {
-  int i, count;
+  int i, count, index;
 
   count = 0;
-  for (i = 0; i < incount; i++) {
-    if (requests[i] != MPI_REQUEST_NULL && requests[i]->complete) {
-      smpi_mpi_wait(&requests[i],
-                    status !=
-                    MPI_STATUS_IGNORE ? &status[i] : MPI_STATUS_IGNORE);
-      indices[count] = i;
-      count++;
-    }
+  for(i = 0; i < incount; i++) {
+     if(smpi_mpi_testany(incount, requests, &index, status)) {
+       indices[count] = index;
+       count++;
+     }
   }
   return count;
 }
@@ -366,29 +443,29 @@ void smpi_mpi_gather(void *sendbuf, int sendcount, MPI_Datatype sendtype,
                      int root, MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, src, index, sendsize, recvsize;
+  int rank, size, src, index;
+  MPI_Aint lb = 0, recvext = 0;
   MPI_Request *requests;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  if (rank != root) {
+  if(rank != root) {
     // Send buffer to root
     smpi_mpi_send(sendbuf, sendcount, sendtype, root, system_tag, comm);
   } else {
-    sendsize = smpi_datatype_size(sendtype);
-    recvsize = smpi_datatype_size(recvtype);
+    // FIXME: check for errors
+    smpi_datatype_extent(recvtype, &lb, &recvext);
     // Local copy from root
-    memcpy(&((char *) recvbuf)[root * recvcount * recvsize], sendbuf,
-           sendcount * sendsize * sizeof(char));
+    smpi_datatype_copy(sendbuf, sendcount, sendtype, 
+        (char *)recvbuf + root * recvcount * recvext, recvcount, recvtype);
     // Receive buffers from senders
     requests = xbt_new(MPI_Request, size - 1);
     index = 0;
-    for (src = 0; src < size; src++) {
-      if (src != root) {
-        requests[index] = smpi_irecv_init(&((char *) recvbuf)
-                                          [src * recvcount * recvsize],
-                                          recvcount, recvtype, src,
-                                          system_tag, comm);
+    for(src = 0; src < size; src++) {
+      if(src != root) {
+        requests[index] = smpi_irecv_init((char *)recvbuf + src * recvcount * recvext, 
+                                          recvcount, recvtype, 
+                                          src, system_tag, comm);
         index++;
       }
     }
@@ -404,28 +481,30 @@ void smpi_mpi_gatherv(void *sendbuf, int sendcount, MPI_Datatype sendtype,
                       MPI_Datatype recvtype, int root, MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, src, index, sendsize;
+  int rank, size, src, index;
+  MPI_Aint lb = 0, recvext = 0;
   MPI_Request *requests;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  if (rank != root) {
+  if(rank != root) {
     // Send buffer to root
     smpi_mpi_send(sendbuf, sendcount, sendtype, root, system_tag, comm);
   } else {
-    sendsize = smpi_datatype_size(sendtype);
+    // FIXME: check for errors
+    smpi_datatype_extent(recvtype, &lb, &recvext);
     // Local copy from root
-    memcpy(&((char *) recvbuf)[displs[root]], sendbuf,
-           sendcount * sendsize * sizeof(char));
+    smpi_datatype_copy(sendbuf, sendcount, sendtype, 
+                       (char *)recvbuf + displs[root] * recvext, 
+                       recvcounts[root], recvtype);
     // Receive buffers from senders
     requests = xbt_new(MPI_Request, size - 1);
     index = 0;
-    for (src = 0; src < size; src++) {
-      if (src != root) {
+    for(src = 0; src < size; src++) {
+      if(src != root) {
         requests[index] =
-            smpi_irecv_init(&((char *) recvbuf)[displs[src]],
-                            recvcounts[src], recvtype, src, system_tag,
-                            comm);
+            smpi_irecv_init((char *)recvbuf + displs[src] * recvext, 
+                            recvcounts[src], recvtype, src, system_tag, comm);
         index++;
       }
     }
@@ -442,28 +521,29 @@ void smpi_mpi_allgather(void *sendbuf, int sendcount,
                         MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, other, index, sendsize, recvsize;
+  int rank, size, other, index;
+  MPI_Aint lb = 0, recvext = 0;
   MPI_Request *requests;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  sendsize = smpi_datatype_size(sendtype);
-  recvsize = smpi_datatype_size(recvtype);
+  // FIXME: check for errors
+  smpi_datatype_extent(recvtype, &lb, &recvext);
   // Local copy from self
-  memcpy(&((char *) recvbuf)[rank * recvcount * recvsize], sendbuf,
-         sendcount * sendsize * sizeof(char));
+  smpi_datatype_copy(sendbuf, sendcount, sendtype, 
+                     (char *)recvbuf + rank * recvcount * recvext, recvcount, 
+                     recvtype);
   // Send/Recv buffers to/from others;
   requests = xbt_new(MPI_Request, 2 * (size - 1));
   index = 0;
-  for (other = 0; other < size; other++) {
-    if (other != rank) {
+  for(other = 0; other < size; other++) {
+    if(other != rank) {
       requests[index] =
           smpi_isend_init(sendbuf, sendcount, sendtype, other, system_tag,
                           comm);
       index++;
-      requests[index] = smpi_irecv_init(&((char *) recvbuf)
-                                        [other * recvcount * recvsize],
-                                        recvcount, recvtype, other,
+      requests[index] = smpi_irecv_init((char *)recvbuf + other * recvcount * recvext, 
+                                        recvcount, recvtype, other, 
                                         system_tag, comm);
       index++;
     }
@@ -480,29 +560,30 @@ void smpi_mpi_allgatherv(void *sendbuf, int sendcount,
                          MPI_Datatype recvtype, MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, other, index, sendsize, recvsize;
+  int rank, size, other, index;
+  MPI_Aint lb = 0, recvext = 0;
   MPI_Request *requests;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  sendsize = smpi_datatype_size(sendtype);
-  recvsize = smpi_datatype_size(recvtype);
+  // FIXME: check for errors
+  smpi_datatype_extent(recvtype, &lb, &recvext);
   // Local copy from self
-  memcpy(&((char *) recvbuf)[displs[rank]], sendbuf,
-         sendcount * sendsize * sizeof(char));
+  smpi_datatype_copy(sendbuf, sendcount, sendtype, 
+                     (char *)recvbuf + displs[rank] * recvext, 
+                     recvcounts[rank], recvtype);
   // Send buffers to others;
   requests = xbt_new(MPI_Request, 2 * (size - 1));
   index = 0;
-  for (other = 0; other < size; other++) {
-    if (other != rank) {
+  for(other = 0; other < size; other++) {
+    if(other != rank) {
       requests[index] =
           smpi_isend_init(sendbuf, sendcount, sendtype, other, system_tag,
                           comm);
       index++;
       requests[index] =
-          smpi_irecv_init(&((char *) recvbuf)[displs[other]],
-                          recvcounts[other], recvtype, other, system_tag,
-                          comm);
+          smpi_irecv_init((char *)recvbuf + displs[other] * recvext, recvcounts[other],
+                          recvtype, other, system_tag, comm);
       index++;
     }
   }
@@ -517,28 +598,28 @@ void smpi_mpi_scatter(void *sendbuf, int sendcount, MPI_Datatype sendtype,
                       int root, MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, dst, index, sendsize, recvsize;
+  int rank, size, dst, index;
+  MPI_Aint lb = 0, sendext = 0;
   MPI_Request *requests;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  if (rank != root) {
+  if(rank != root) {
     // Recv buffer from root
     smpi_mpi_recv(recvbuf, recvcount, recvtype, root, system_tag, comm,
                   MPI_STATUS_IGNORE);
   } else {
-    sendsize = smpi_datatype_size(sendtype);
-    recvsize = smpi_datatype_size(recvtype);
+    // FIXME: check for errors
+    smpi_datatype_extent(sendtype, &lb, &sendext);
     // Local copy from root
-    memcpy(recvbuf, &((char *) sendbuf)[root * sendcount * sendsize],
-           recvcount * recvsize * sizeof(char));
+    smpi_datatype_copy((char *)sendbuf + root * sendcount * sendext,
+      sendcount, sendtype, recvbuf, recvcount, recvtype);
     // Send buffers to receivers
     requests = xbt_new(MPI_Request, size - 1);
     index = 0;
-    for (dst = 0; dst < size; dst++) {
-      if (dst != root) {
-        requests[index] = smpi_isend_init(&((char *) sendbuf)
-                                          [dst * sendcount * sendsize],
+    for(dst = 0; dst < size; dst++) {
+      if(dst != root) {
+        requests[index] = smpi_isend_init((char *)sendbuf + dst * sendcount * sendext, 
                                           sendcount, sendtype, dst,
                                           system_tag, comm);
         index++;
@@ -556,30 +637,30 @@ void smpi_mpi_scatterv(void *sendbuf, int *sendcounts, int *displs,
                        MPI_Datatype recvtype, int root, MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, dst, index, sendsize, recvsize;
+  int rank, size, dst, index;
+  MPI_Aint lb = 0, sendext = 0;
   MPI_Request *requests;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  if (rank != root) {
+  if(rank != root) {
     // Recv buffer from root
     smpi_mpi_recv(recvbuf, recvcount, recvtype, root, system_tag, comm,
                   MPI_STATUS_IGNORE);
   } else {
-    sendsize = smpi_datatype_size(sendtype);
-    recvsize = smpi_datatype_size(recvtype);
+    // FIXME: check for errors
+    smpi_datatype_extent(sendtype, &lb, &sendext);
     // Local copy from root
-    memcpy(recvbuf, &((char *) sendbuf)[displs[root]],
-           recvcount * recvsize * sizeof(char));
+    smpi_datatype_copy((char *)sendbuf + displs[root] * sendext, sendcounts[root], 
+                       sendtype, recvbuf, recvcount, recvtype);
     // Send buffers to receivers
     requests = xbt_new(MPI_Request, size - 1);
     index = 0;
-    for (dst = 0; dst < size; dst++) {
-      if (dst != root) {
+    for(dst = 0; dst < size; dst++) {
+      if(dst != root) {
         requests[index] =
-            smpi_isend_init(&((char *) sendbuf)[displs[dst]],
-                            sendcounts[dst], sendtype, dst, system_tag,
-                            comm);
+            smpi_isend_init((char *)sendbuf + displs[dst] * sendext, sendcounts[dst], 
+                            sendtype, dst, system_tag, comm);
         index++;
       }
     }
@@ -595,27 +676,31 @@ void smpi_mpi_reduce(void *sendbuf, void *recvbuf, int count,
                      MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, src, index, datasize;
+  int rank, size, src, index;
+  MPI_Aint lb = 0, dataext = 0;
   MPI_Request *requests;
   void **tmpbufs;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  if (rank != root) {
+  if(rank != root) {
     // Send buffer to root
     smpi_mpi_send(sendbuf, count, datatype, root, system_tag, comm);
   } else {
-    datasize = smpi_datatype_size(datatype);
+    // FIXME: check for errors
+    smpi_datatype_extent(datatype, &lb, &dataext);
     // Local copy from root
-    memcpy(recvbuf, sendbuf, count * datasize * sizeof(char));
+    smpi_datatype_copy(sendbuf, count, datatype, recvbuf, count, datatype);
     // Receive buffers from senders
     //TODO: make a MPI_barrier here ?
     requests = xbt_new(MPI_Request, size - 1);
     tmpbufs = xbt_new(void *, size - 1);
     index = 0;
-    for (src = 0; src < size; src++) {
-      if (src != root) {
-        tmpbufs[index] = xbt_malloc(count * datasize);
+    for(src = 0; src < size; src++) {
+      if(src != root) {
+        // 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, src,
                             system_tag, comm);
@@ -624,14 +709,15 @@ void smpi_mpi_reduce(void *sendbuf, void *recvbuf, int count,
     }
     // Wait for completion of irecv's.
     smpi_mpi_startall(size - 1, requests);
-    for (src = 0; src < size - 1; src++) {
+    for(src = 0; src < size - 1; src++) {
       index = smpi_mpi_waitany(size - 1, requests, MPI_STATUS_IGNORE);
-      if (index == MPI_UNDEFINED) {
+      XBT_VERB("finished waiting any request with index %d", index);
+      if(index == MPI_UNDEFINED) {
         break;
       }
       smpi_op_apply(op, tmpbufs[index], recvbuf, &count, &datatype);
     }
-    for (index = 0; index < size - 1; index++) {
+    for(index = 0; index < size - 1; index++) {
       xbt_free(tmpbufs[index]);
     }
     xbt_free(tmpbufs);
@@ -644,96 +730,57 @@ void smpi_mpi_allreduce(void *sendbuf, void *recvbuf, int count,
 {
   smpi_mpi_reduce(sendbuf, recvbuf, count, datatype, op, 0, comm);
   smpi_mpi_bcast(recvbuf, count, datatype, 0, comm);
-
-/*
-FIXME: buggy implementation
-
-  int system_tag = 666;
-  int rank, size, other, index, datasize;
-  MPI_Request* requests;
-  void** tmpbufs;
-
-  rank = smpi_comm_rank(comm);
-  size = smpi_comm_size(comm);
-  datasize = smpi_datatype_size(datatype);
-  // Local copy from self
-  memcpy(recvbuf, sendbuf, count * datasize * sizeof(char));
-  // Send/Recv buffers to/from others;
-  //TODO: make a MPI_barrier here ?
-  requests = xbt_new(MPI_Request, 2 * (size - 1));
-  tmpbufs = xbt_new(void*, size - 1);
-  index = 0;
-  for(other = 0; other < size; other++) {
-    if(other != rank) {
-      tmpbufs[index / 2] = xbt_malloc(count * datasize);
-      requests[index] = smpi_mpi_isend(sendbuf, count, datatype, other, system_tag, comm);
-      requests[index + 1] = smpi_mpi_irecv(tmpbufs[index / 2], count, datatype, other, system_tag, comm);
-      index += 2;
-    }
-  }
-  // Wait for completion of all comms.
-  for(other = 0; other < 2 * (size - 1); other++) {
-    index = smpi_mpi_waitany(size - 1, requests, MPI_STATUS_IGNORE);
-    if(index == MPI_UNDEFINED) {
-      break;
-    }
-    if((index & 1) == 1) {
-      // Request is odd: it's a irecv
-      smpi_op_apply(op, tmpbufs[index / 2], recvbuf, &count, &datatype);
-    }
-  }
-  for(index = 0; index < size - 1; index++) {
-    xbt_free(tmpbufs[index]);
-  }
-  xbt_free(tmpbufs);
-  xbt_free(requests);
-*/
 }
 
 void smpi_mpi_scan(void *sendbuf, void *recvbuf, int count,
                    MPI_Datatype datatype, MPI_Op op, MPI_Comm comm)
 {
   int system_tag = 666;
-  int rank, size, other, index, datasize;
-  int total;
+  int rank, size, other, index;
+  MPI_Aint lb = 0, dataext = 0;
   MPI_Request *requests;
   void **tmpbufs;
 
   rank = smpi_comm_rank(comm);
   size = smpi_comm_size(comm);
-  datasize = smpi_datatype_size(datatype);
+
+  // FIXME: check for errors
+  smpi_datatype_extent(datatype, &lb, &dataext);
+
   // Local copy from self
-  memcpy(recvbuf, sendbuf, count * datasize * sizeof(char));
+  smpi_datatype_copy(sendbuf, count, datatype, recvbuf, count, datatype);
+
   // Send/Recv buffers to/from others;
-  total = rank + (size - (rank + 1));
-  requests = xbt_new(MPI_Request, total);
+  requests = xbt_new(MPI_Request, size - 1);
   tmpbufs = xbt_new(void *, rank);
   index = 0;
-  for (other = 0; other < rank; other++) {
-    tmpbufs[index] = xbt_malloc(count * datasize);
+  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++) {
+  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);
-  for (other = 0; other < total; other++) {
+  for(other = 0; other < size - 1; other++) {
     index = smpi_mpi_waitany(size - 1, requests, MPI_STATUS_IGNORE);
-    if (index == MPI_UNDEFINED) {
+    if(index == MPI_UNDEFINED) {
       break;
     }
-    if (index < rank) {
+    if(index < rank) {
       // #Request is below rank: it's a irecv
       smpi_op_apply(op, tmpbufs[index], recvbuf, &count, &datatype);
     }
   }
-  for (index = 0; index < size - 1; index++) {
+  for(index = 0; index < rank; index++) {
     xbt_free(tmpbufs[index]);
   }
   xbt_free(tmpbufs);