X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/d13b1659a0c2551ee41b287a269e391bb2d7bc8a..3fe150481a6802850ebb47a7f4a1b77c53f2cd99:/src/smpi/smpi_base.c

diff --git a/src/smpi/smpi_base.c b/src/smpi/smpi_base.c
index af7deebdcd..a5d2d7337d 100644
--- a/src/smpi/smpi_base.c
+++ b/src/smpi/smpi_base.c
@@ -135,12 +135,19 @@ static double smpi_os(double size)
   unsigned int iter = 0;
   s_smpi_factor_t fact;
   double current=0.0;
+  // Iterate over all the sections that were specified and find the right
+  // value. (fact.factor represents the interval sizes; we want to find the
+  // section that has fact.factor <= size and no other such fact.factor <= size)
+  // Note: parse_factor() (used before) already sorts the dynar we iterate over!
   xbt_dynar_foreach(smpi_os_values, iter, fact) {
-    if (size <= fact.factor) {
+    if (size <= fact.factor) { // Values already too large, use the previously
+                               // computed value of current!
         XBT_DEBUG("os : %f <= %ld return %f", size, fact.factor, current);
       return current;
     }else{
-      current=fact.values[0]+fact.values[1]*size;
+      // If the next section is too large, the current section must be used.
+      // Hence, save the cost, as we might have to use it.
+      current = fact.values[0]+fact.values[1]*size;
     }
   }
   XBT_DEBUG("os : %f > %ld return %f", size, fact.factor, current);
@@ -157,12 +164,19 @@ static double smpi_ois(double size)
   unsigned int iter = 0;
   s_smpi_factor_t fact;
   double current=0.0;
+  // Iterate over all the sections that were specified and find the right
+  // value. (fact.factor represents the interval sizes; we want to find the
+  // section that has fact.factor <= size and no other such fact.factor <= size)
+  // Note: parse_factor() (used before) already sorts the dynar we iterate over!
   xbt_dynar_foreach(smpi_ois_values, iter, fact) {
-    if (size <= fact.factor) {
+    if (size <= fact.factor) { // Values already too large, use the previously
+                               // computed value of current!
         XBT_DEBUG("ois : %f <= %ld return %f", size, fact.factor, current);
       return current;
     }else{
-      current=fact.values[0]+fact.values[1]*size;
+      // If the next section is too large, the current section must be used.
+      // Hence, save the cost, as we might have to use it.
+      current = fact.values[0]+fact.values[1]*size;
     }
   }
   XBT_DEBUG("ois : %f > %ld return %f", size, fact.factor, current);
@@ -179,12 +193,20 @@ static double smpi_or(double size)
   unsigned int iter = 0;
   s_smpi_factor_t fact;
   double current=0.0;
+  // Iterate over all the sections that were specified and find the right
+  // value. (fact.factor represents the interval sizes; we want to find the
+  // section that has fact.factor <= size and no other such fact.factor <= size)
+  // Note: parse_factor() (used before) already sorts the dynar we iterate over!
   xbt_dynar_foreach(smpi_or_values, iter, fact) {
-    if (size <= fact.factor) {
+    if (size <= fact.factor) { // Values already too large, use the previously
+                               // computed value of current!
         XBT_DEBUG("or : %f <= %ld return %f", size, fact.factor, current);
       return current;
-    }else
+    } else {
+      // If the next section is too large, the current section must be used.
+      // Hence, save the cost, as we might have to use it.
       current=fact.values[0]+fact.values[1]*size;
+    }
   }
   XBT_DEBUG("or : %f > %ld return %f", size, fact.factor, current);
 
@@ -196,7 +218,12 @@ double smpi_mpi_wtime(){
   if (smpi_process_initialized() && !smpi_process_finalized() && !smpi_process_get_sampling()) {
     smpi_bench_end();
     time = SIMIX_get_clock();
-    //to avoid deadlocks if called too many times
+    // to avoid deadlocks if used as a break condition, such as
+    //     while (MPI_Wtime(...) < time_limit) {
+    //       ....
+    //     }
+    // because the time will not normally advance when only calls to MPI_Wtime
+    // are made -> deadlock (MPI_Wtime never reaches the time limit)
     if(smpi_wtime_sleep > 0) simcall_process_sleep(smpi_wtime_sleep);
     smpi_bench_begin();
   } else {
@@ -269,35 +296,6 @@ void smpi_empty_status(MPI_Status * status)
   }
 }
 
-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");
-    if (action_fp == NULL)
-      xbt_die("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;
@@ -744,8 +742,12 @@ int smpi_mpi_test(MPI_Request * request, MPI_Status * status) {
 
   //assume that request is not MPI_REQUEST_NULL (filtered in PMPI_Test or smpi_mpi_testall before)
 
-  //to avoid deadlocks
-  //multiplier to the sleeptime, to increase speed of execution, each failed test will increase it
+  // to avoid deadlocks if used as a break condition, such as
+  //     while (MPI_Test(request, flag, status) && flag) {
+  //     }
+  // because the time will not normally advance when only calls to MPI_Test
+  // are made -> deadlock
+  // multiplier to the sleeptime, to increase speed of execution, each failed test will increase it
   static int nsleeps = 1;
   if(smpi_test_sleep > 0)  simcall_process_sleep(nsleeps*smpi_test_sleep);
 
@@ -854,8 +856,9 @@ void smpi_mpi_iprobe(int source, int tag, MPI_Comm comm, int* flag, MPI_Status*
   MPI_Request request =build_request(NULL, 0, MPI_CHAR, source == MPI_ANY_SOURCE ? MPI_ANY_SOURCE : smpi_group_index(smpi_comm_group(comm), source), smpi_comm_rank(comm), tag,
             comm, PERSISTENT | RECV);
 
-  //to avoid deadlock, we have to sleep some time here, or the timer won't advance and we will only do iprobe simcalls
-  //multiplier to the sleeptime, to increase speed of execution, each failed iprobe will increase it
+  // to avoid deadlock, we have to sleep some time here, or the timer won't advance and we will only do iprobe simcalls
+  // (especially when used as a break condition, such as while(MPI_Iprobe(...)) ... )
+  // multiplier to the sleeptime, to increase speed of execution, each failed iprobe will increase it
   static int nsleeps = 1;
   if(smpi_iprobe_sleep > 0)  simcall_process_sleep(nsleeps*smpi_iprobe_sleep);
   // behave like a receive, but don't do it
@@ -863,31 +866,31 @@ void smpi_mpi_iprobe(int source, int tag, MPI_Comm comm, int* flag, MPI_Status*
 
   print_request("New iprobe", request);
   // We have to test both mailboxes as we don't know if we will receive one one or another
-    if (sg_cfg_get_int("smpi/async_small_thres")>0){
-        mailbox = smpi_process_mailbox_small();
-        XBT_DEBUG("trying to probe the perm recv mailbox");
-        request->action = simcall_comm_iprobe(mailbox, 0, request->src, request->tag, &match_recv, (void*)request);
-    }
-    if (request->action==NULL){
-	mailbox = smpi_process_mailbox();
-        XBT_DEBUG("trying to probe the other mailbox");
-        request->action = simcall_comm_iprobe(mailbox, 0, request->src,request->tag, &match_recv, (void*)request);
-    }
+  if (sg_cfg_get_int("smpi/async_small_thres")>0){
+      mailbox = smpi_process_mailbox_small();
+      XBT_DEBUG("trying to probe the perm recv mailbox");
+      request->action = simcall_comm_iprobe(mailbox, 0, request->src, request->tag, &match_recv, (void*)request);
+  }
+  if (request->action==NULL){
+  mailbox = smpi_process_mailbox();
+      XBT_DEBUG("trying to probe the other mailbox");
+      request->action = simcall_comm_iprobe(mailbox, 0, request->src,request->tag, &match_recv, (void*)request);
+  }
 
-  if(request->action){
+  if (request->action){
     MPI_Request req = (MPI_Request)SIMIX_comm_get_src_data(request->action);
     *flag = 1;
     if(status != MPI_STATUS_IGNORE && !(req->flags & PREPARED)) {
       status->MPI_SOURCE = smpi_group_rank(smpi_comm_group(comm), req->src);
-      status->MPI_TAG = req->tag;
-      status->MPI_ERROR = MPI_SUCCESS;
-      status->count = req->real_size;
+      status->MPI_TAG    = req->tag;
+      status->MPI_ERROR  = MPI_SUCCESS;
+      status->count      = req->real_size;
     }
     nsleeps=1;//reset the number of sleeps we will do next time
   }
   else {
-      *flag = 0;
-      nsleeps++;
+    *flag = 0;
+    nsleeps++;
   }
   smpi_mpi_request_free(&request);