X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/a846b9415542cdaa8ba5d0f7efeadecb56ba7c2c..ececc8c70378c26333560a86aeae6e1272459070:/examples/msg/actions/actions.c

diff --git a/examples/msg/actions/actions.c b/examples/msg/actions/actions.c
index 758ebf111e..091f7ea606 100644
--- a/examples/msg/actions/actions.c
+++ b/examples/msg/actions/actions.c
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include "msg/msg.h"            /* Yeah! If you want to use msg, you need to include msg/msg.h */
+#include "msg/mailbox.h"        /* we play funny tricks with mailboxes and rdv points */
 #include "simix/simix.h"        /* semaphores for the barrier */
 #include "xbt.h"                /* calloc, printf */
 #include "instr/instr_private.h"
@@ -108,8 +109,8 @@ static void action_Isend(const char *const *action)
 
 
   sprintf(to, "%s_%s", MSG_process_get_name(MSG_process_self()),action[2]);
-  msg_comm_t comm =
-      MSG_task_isend( MSG_task_create(to,0,parse_double(size),NULL), to);
+  m_task_t task = MSG_task_create(to,0,parse_double(size),NULL);
+  msg_comm_t comm = MSG_task_isend_with_matching(task, to, /*matching madness*/NULL,task);
   xbt_dynar_push(globals->isends,&comm);
 
   XBT_DEBUG("Isend on %s", MSG_process_get_name(MSG_process_self()));
@@ -118,6 +119,12 @@ static void action_Isend(const char *const *action)
   asynchronous_cleanup();
 }
 
+static int task_matching(void*sent_task,void*ignored) {
+  m_task_t t = (m_task_t)sent_task;
+  if (t!=NULL && MSG_task_get_data_size(t)<65536)
+    return 1; /* that's supposed to be already arrived */
+  return 0; /* rendez-vous mode: it's not there yet */
+}
 
 static void action_recv(const char *const *action)
 {
@@ -132,6 +139,22 @@ static void action_recv(const char *const *action)
   if (XBT_LOG_ISENABLED(actions, xbt_log_priority_verbose))
     name = xbt_str_join_array(action, " ");
 
+  /* The next chunk is to deal with the fact that for short messages,
+   * if the send occurs before the receive, the message is already sent and
+   * buffered on receiver side when the recv() occurs.
+   *
+   * So the next chunk detects this fact and cancel the simix communication instead.
+   */
+
+  /* make sure the rdv is created on need by asking to MSG instead of simix directly */
+  smx_rdv_t rdv = MSG_mailbox_get_by_alias(mailbox_name);
+  smx_action_t act = SIMIX_comm_get_send_match(rdv,task_matching,NULL);
+  if (act!=NULL){
+    /* FIXME account for the memcopy time if needed */
+    SIMIX_comm_finish(act);
+    return;
+  }
+
 #ifdef HAVE_TRACING
   int rank = get_rank(MSG_process_get_name(MSG_process_self()));
   int src_traced = get_rank(action[2]);