X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/a35265d3c8fa860614bab6b7a438ad0cc2803e79..77ad7d74e9c7c82e4338596278600b18bb87b3e3:/src/simgrid/sg_config.c

diff --git a/src/simgrid/sg_config.c b/src/simgrid/sg_config.c
index 34e5b43f32..7d4da0ba03 100644
--- a/src/simgrid/sg_config.c
+++ b/src/simgrid/sg_config.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2009-2010, 2012-2013. The SimGrid Team.
+/* Copyright (c) 2009-2010, 2012-2014. The SimGrid Team.
  * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
@@ -35,6 +35,12 @@ xbt_cfg_t _sg_cfg_set = NULL;
  */
 int _sg_cfg_init_status = 0;
 
+/* instruct the upper layer (simix or simdag) to exit as soon as possible
+ */
+int _sg_cfg_exit_asap = 0;
+
+#define sg_cfg_exit_early() do { _sg_cfg_exit_asap = 1; return; } while (0)
+
 /* Parse the command line, looking for options */
 static void sg_config_cmd_line(int *argc, char **argv)
 {
@@ -49,6 +55,9 @@ static void sg_config_cmd_line(int *argc, char **argv)
 
       xbt_cfg_set_parse(_sg_cfg_set, opt);
       XBT_DEBUG("Did apply '%s' as config setting", opt);
+    } else if (!strcmp(argv[i], "--version")) {
+      printf("%s\n", SIMGRID_VERSION_STRING);
+      shall_exit = 1;
     } else if (!strcmp(argv[i], "--cfg-help") || !strcmp(argv[i], "--help")) {
       printf
           ("Description of the configuration accepted by this simulator:\n");
@@ -58,6 +67,7 @@ static void sg_config_cmd_line(int *argc, char **argv)
 "Each of these configurations can be used by adding\n"
 "    --cfg=<option name>:<option value>\n"
 "to the command line.\n"
+"\n"
 "You can also use --help-models to see the details of all models known by this simulator.\n"
 #ifdef HAVE_TRACING
 "\n"
@@ -65,6 +75,8 @@ static void sg_config_cmd_line(int *argc, char **argv)
 #endif
 "\n"
 "You can also use --help-logs and --help-log-categories to see the details of logging output.\n"
+"\n"
+"You can also use --version to get SimGrid version information.\n"
 "\n"
         );
       shall_exit = 1;
@@ -96,10 +108,29 @@ static void sg_config_cmd_line(int *argc, char **argv)
     argv[j] = NULL;
     *argc = j;
   }
-  if (shall_exit) {
-    _sg_cfg_init_status = 1;        // get everything cleanly cleaned on exit
-    exit(0);
+  if (shall_exit)
+    sg_cfg_exit_early();
+}
+
+/* callback of the plugin variable */
+static void _sg_cfg_cb__plugin(const char *name, int pos)
+{
+  char *val;
+
+  XBT_VERB("PLUGIN");
+  xbt_assert(_sg_cfg_init_status < 2,
+              "Cannot load a plugin after the initialization");
+
+  val = xbt_cfg_get_string(_sg_cfg_set, name);
+
+  if (!strcmp(val, "help")) {
+    model_help("plugin", surf_plugin_description);
+    sg_cfg_exit_early();
   }
+
+  /* New Module missing */
+  int plugin_id = find_model_description(surf_plugin_description, val);
+  surf_plugin_description[plugin_id].model_init_preparse();
 }
 
 /* callback of the workstation/model variable */
@@ -114,13 +145,32 @@ static void _sg_cfg_cb__workstation_model(const char *name, int pos)
 
   if (!strcmp(val, "help")) {
     model_help("workstation", surf_workstation_model_description);
-    exit(0);
+    sg_cfg_exit_early();
   }
 
   /* Make sure that the model exists */
   find_model_description(surf_workstation_model_description, val);
 }
 
+/* callback of the vm_workstation/model variable */
+static void _sg_cfg_cb__vm_workstation_model(const char *name, int pos)
+{
+  char *val;
+
+  xbt_assert(_sg_cfg_init_status < 2,
+              "Cannot change the model after the initialization");
+
+  val = xbt_cfg_get_string(_sg_cfg_set, name);
+
+  if (!strcmp(val, "help")) {
+    model_help("vm_workstation", surf_vm_workstation_model_description);
+    sg_cfg_exit_early();
+  }
+
+  /* Make sure that the model exists */
+  find_model_description(surf_vm_workstation_model_description, val);
+}
+
 /* callback of the cpu/model variable */
 static void _sg_cfg_cb__cpu_model(const char *name, int pos)
 {
@@ -133,7 +183,7 @@ static void _sg_cfg_cb__cpu_model(const char *name, int pos)
 
   if (!strcmp(val, "help")) {
     model_help("CPU", surf_cpu_model_description);
-    exit(0);
+    sg_cfg_exit_early();
   }
 
   /* New Module missing */
@@ -152,7 +202,7 @@ static void _sg_cfg_cb__optimization_mode(const char *name, int pos)
 
   if (!strcmp(val, "help")) {
     model_help("optimization", surf_optimization_mode_description);
-    exit(0);
+    sg_cfg_exit_early();
   }
 
   /* New Module missing */
@@ -171,7 +221,7 @@ static void _sg_cfg_cb__storage_mode(const char *name, int pos)
 
   if (!strcmp(val, "help")) {
     model_help("storage", surf_storage_model_description);
-    exit(0);
+    sg_cfg_exit_early();
   }
 
   /* New Module missing */
@@ -190,7 +240,7 @@ static void _sg_cfg_cb__network_model(const char *name, int pos)
 
   if (!strcmp(val, "help")) {
     model_help("network", surf_network_model_description);
-    exit(0);
+    sg_cfg_exit_early();
   }
 
   /* New Module missing */
@@ -243,7 +293,7 @@ static void _sg_cfg_cb__coll(const char *category,
 
   if (!strcmp(val, "help")) {
     coll_help(category, table);
-    exit(0);
+    sg_cfg_exit_early();
   }
 
   /* New Module missing */
@@ -338,6 +388,12 @@ static void _sg_cfg_cb_context_stack_size(const char *name, int pos)
   smx_context_stack_size = xbt_cfg_get_int(_sg_cfg_set, name) * 1024;
 }
 
+static void _sg_cfg_cb_context_guard_size(const char *name, int pos)
+{
+  smx_context_guard_size_was_set = 1;
+  smx_context_guard_size = xbt_cfg_get_int(_sg_cfg_set, name) * xbt_pagesize;
+}
+
 static void _sg_cfg_cb_contexts_nthreads(const char *name, int pos)
 {
   SIMIX_context_set_nthreads(xbt_cfg_get_int(_sg_cfg_set, name));
@@ -398,105 +454,81 @@ static void _sg_cfg_cb__gtnets_jitter_seed(const char *name, int pos)
 }
 #endif
 
+/* build description line with possible values */
+static void describe_model(char *result,
+                           const s_surf_model_description_t model_description[],
+                           const char *name,
+                           const char *description)
+{
+  char *p = result +
+    sprintf(result, "%s. Possible values: %s", description,
+            model_description[0].name ? model_description[0].name : "n/a");
+  int i;
+  for (i = 1; model_description[i].name; i++)
+    p += sprintf(p, ", %s", model_description[i].name);
+  sprintf(p,
+      ".\n       (use 'help' as a value to see the long description of each %s)",
+          name);
+}
+
 /* create the config set, register what should be and parse the command line*/
 void sg_config_init(int *argc, char **argv)
 {
-  char *description = xbt_malloc(1024), *p = description;
-  int i;
+  char description[1024];
 
   /* Create the configuration support */
   if (_sg_cfg_init_status == 0) { /* Only create stuff if not already inited */
-    sprintf(description,
-            "The model to use for the CPU. Possible values: ");
-    p = description;
-    while (*(++p) != '\0');
-    for (i = 0; surf_cpu_model_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_cpu_model_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each model)");
+
+    /* Plugins configuration */
+    describe_model(description, surf_plugin_description,
+                   "plugin", "The plugins");
+    xbt_cfg_register(&_sg_cfg_set, "plugin", description,
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__plugin, NULL);
+
+    describe_model(description, surf_cpu_model_description,
+                   "model", "The model to use for the CPU");
     xbt_cfg_register(&_sg_cfg_set, "cpu/model", description,
                      xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__cpu_model, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "cpu/model", "Cas01");
 
-    while (*(++p) != '\0');
-    for (i = 0; surf_optimization_mode_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_optimization_mode_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each optimization mode)");
+    describe_model(description, surf_optimization_mode_description,
+                   "optimization mode",
+                   "The optimization modes to use for the CPU");
     xbt_cfg_register(&_sg_cfg_set, "cpu/optim", description,
                      xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__optimization_mode, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "cpu/optim", "Lazy");
 
-    sprintf(description,
-            "The model to use for the storage. Possible values: ");
-    p = description;
-    while (*(++p) != '\0');
-    for (i = 0; surf_storage_model_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_storage_model_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each model)");
+    describe_model(description, surf_storage_model_description,
+                   "model", "The model to use for the storage");
     xbt_cfg_register(&_sg_cfg_set, "storage/model", description,
                      xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__storage_mode, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "storage/model", "default");
 
-    /* ********************************************************************* */
-    /* TUTORIAL: New model                                                   */
-    sprintf(description,
-            "The model to use for the New model. Possible values: ");
-    p = description;
-    while (*(++p) != '\0');
-    for (i = 0; surf_new_model_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_new_model_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each model)");
-    xbt_cfg_register(&_sg_cfg_set, "new_model/model", description,
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__storage_mode, NULL);
-    xbt_cfg_setdefault_string(_sg_cfg_set, "new_model/model", "default");
-    /* ********************************************************************* */
-
-    sprintf(description,
-            "The model to use for the network. Possible values: ");
-    p = description;
-    while (*(++p) != '\0');
-    for (i = 0; surf_network_model_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_network_model_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each model)");
+    describe_model(description, surf_network_model_description,
+                   "model", "The model to use for the network");
     xbt_cfg_register(&_sg_cfg_set, "network/model", description,
                      xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__network_model, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "network/model", "LV08");
 
-    sprintf(description,
-            "The optimization modes to use for the network. Possible values: ");
-    p = description;
-    while (*(++p) != '\0');
-    for (i = 0; surf_optimization_mode_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_optimization_mode_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each optimization mode)");
+    describe_model(description, surf_optimization_mode_description,
+                   "optimization mode",
+                   "The optimization modes to use for the network");
     xbt_cfg_register(&_sg_cfg_set, "network/optim", description,
                      xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__optimization_mode, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "network/optim", "Lazy");
 
-    sprintf(description,
-            "The model to use for the workstation. Possible values: ");
-    p = description;
-    while (*(++p) != '\0');
-    for (i = 0; surf_workstation_model_description[i].name; i++)
-      p += sprintf(p, "%s%s", (i == 0 ? "" : ", "),
-                   surf_workstation_model_description[i].name);
-    sprintf(p,
-            ".\n       (use 'help' as a value to see the long description of each model)");
+    describe_model(description, surf_workstation_model_description,
+                   "model", "The model to use for the workstation");
     xbt_cfg_register(&_sg_cfg_set, "workstation/model", description,
                      xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__workstation_model, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "workstation/model", "default");
 
+    describe_model(description, surf_vm_workstation_model_description,
+                   "model", "The model to use for the vm workstation");
+    xbt_cfg_register(&_sg_cfg_set, "vm_workstation/model", description,
+                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__vm_workstation_model, NULL);
+    xbt_cfg_setdefault_string(_sg_cfg_set, "vm_workstation/model", "default");
+
     xbt_cfg_register(&_sg_cfg_set, "network/TCP_gamma",
                      "Size of the biggest TCP window (cat /proc/sys/net/ipv4/tcp_[rw]mem for recv/send window; Use the last given value, which is the max window size)",
                      xbt_cfgelm_double, 1, 1, _sg_cfg_cb__tcp_gamma, NULL);
@@ -512,7 +544,8 @@ void sg_config_init(int *argc, char **argv)
     xbt_cfg_register(&_sg_cfg_set, "network/sender_gap",
                      "Minimum gap between two overlapping sends",
                      xbt_cfgelm_double, 1, 1, _sg_cfg_cb__sender_gap, NULL);
-    /* default for "network/sender_gap" is set in network.c */
+    /* real default for "network/sender_gap" is set in network_smpi.cpp */
+    xbt_cfg_setdefault_double(_sg_cfg_set, "network/sender_gap", NAN);
 
     xbt_cfg_register(&_sg_cfg_set, "network/latency_factor",
                      "Correction factor to apply to the provided latency (default value set by network model)",
@@ -527,102 +560,135 @@ void sg_config_init(int *argc, char **argv)
     xbt_cfg_register(&_sg_cfg_set, "network/weight_S",
                      "Correction factor to apply to the weight of competing streams (default value set by network model)",
                      xbt_cfgelm_double, 1, 1, _sg_cfg_cb__weight_S, NULL);
-    /* default for "network/weight_S" is set in network.c */
+    /* real default for "network/weight_S" is set in network_*.cpp */
+    xbt_cfg_setdefault_double(_sg_cfg_set, "network/weight_S", NAN);
 
     /* Inclusion path */
     xbt_cfg_register(&_sg_cfg_set, "path",
                      "Lookup path for inclusions in platform and deployment XML files",
-                     xbt_cfgelm_string, 0, 0, _sg_cfg_cb__surf_path, NULL);
+                     xbt_cfgelm_string, 1, 0, _sg_cfg_cb__surf_path, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "cpu/maxmin_selective_update",
                      "Update the constraint set propagating recursively to others constraints (off by default when optim is set to lazy)",
-                     xbt_cfgelm_boolean, 0, 1, NULL, NULL);
+                     xbt_cfgelm_boolean, 1, 1, NULL, NULL);
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "cpu/maxmin_selective_update", "no");
 
     xbt_cfg_register(&_sg_cfg_set, "network/maxmin_selective_update",
                      "Update the constraint set propagating recursively to others constraints (off by default when optim is set to lazy)",
-                     xbt_cfgelm_boolean, 0, 1, NULL, NULL);
+                     xbt_cfgelm_boolean, 1, 1, NULL, NULL);
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "network/maxmin_selective_update", "no");
 
 #ifdef HAVE_MC
     /* do model-checking */
     xbt_cfg_register(&_sg_cfg_set, "model-check",
                      "Verify the system through model-checking instead of simulating it (EXPERIMENTAL)",
-                     xbt_cfgelm_boolean, 0, 1, _sg_cfg_cb_model_check, NULL);
+                     xbt_cfgelm_boolean, 1, 1, _sg_cfg_cb_model_check, NULL);
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "model-check", "no");
 
     /* do stateful model-checking */
     xbt_cfg_register(&_sg_cfg_set, "model-check/checkpoint",
                      "Specify the amount of steps between checkpoints during stateful model-checking (default: 0 => stateless verification). "
-                     "If value=on, one checkpoint is saved for each step => faster verification, but huge memory consumption; higher values are good compromises between speed and memory consumption.",
-                     xbt_cfgelm_int, 0, 1, _mc_cfg_cb_checkpoint, NULL);
+                     "If value=1, one checkpoint is saved for each step => faster verification, but huge memory consumption; higher values are good compromises between speed and memory consumption.",
+                     xbt_cfgelm_int, 1, 1, _mc_cfg_cb_checkpoint, NULL);
     xbt_cfg_setdefault_int(_sg_cfg_set, "model-check/checkpoint", 0);
 
     /* do liveness model-checking */
     xbt_cfg_register(&_sg_cfg_set, "model-check/property",
                      "Specify the name of the file containing the property. It must be the result of the ltl2ba program.",
-                     xbt_cfgelm_string, 0, 1, _mc_cfg_cb_property, NULL);
+                     xbt_cfgelm_string, 1, 1, _mc_cfg_cb_property, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "model-check/property", "");
 
+    /* do communications determinism model-checking */
+    xbt_cfg_register(&_sg_cfg_set, "model-check/communications_determinism",
+                     "Enable/disable the detection of determinism in the communications schemes",
+                     xbt_cfgelm_boolean, 1, 1, _mc_cfg_cb_comms_determinism, NULL);
+    xbt_cfg_setdefault_boolean(_sg_cfg_set, "model-check/communications_determinism", "no");
+
+    /* do send determinism model-checking */
+    xbt_cfg_register(&_sg_cfg_set, "model-check/send_determinism",
+                     "Enable/disable the detection of send-determinism in the communications schemes",
+                     xbt_cfgelm_boolean, 1, 1, _mc_cfg_cb_send_determinism, NULL);
+    xbt_cfg_setdefault_boolean(_sg_cfg_set, "model-check/send_determinism", "no");
+
     /* Specify the kind of model-checking reduction */
     xbt_cfg_register(&_sg_cfg_set, "model-check/reduction",
                      "Specify the kind of exploration reduction (either none or DPOR)",
-                     xbt_cfgelm_string, 0, 1, _mc_cfg_cb_reduce, NULL);
+                     xbt_cfgelm_string, 1, 1, _mc_cfg_cb_reduce, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "model-check/reduction", "dpor");
 
     /* Enable/disable timeout for wait requests with model-checking */
     xbt_cfg_register(&_sg_cfg_set, "model-check/timeout",
                      "Enable/Disable timeout for wait requests",
-                     xbt_cfgelm_boolean, 0, 1, _mc_cfg_cb_timeout, NULL);
+                     xbt_cfgelm_boolean, 1, 1, _mc_cfg_cb_timeout, NULL);
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "model-check/timeout", "no");
 
+    /* Enable/disable global hash computation with model-checking */
+    xbt_cfg_register(&_sg_cfg_set, "model-check/hash",
+                     "Enable/Disable state hash for state comparison (exprimental)",
+                     xbt_cfgelm_boolean, 1, 1, _mc_cfg_cb_hash, NULL);
+    xbt_cfg_setdefault_boolean(_sg_cfg_set, "model-check/hash", "no");
+
     /* Set max depth exploration */
     xbt_cfg_register(&_sg_cfg_set, "model-check/max_depth",
                      "Specify the max depth of exploration (default : 1000)",
-                     xbt_cfgelm_int, 0, 1, _mc_cfg_cb_max_depth, NULL);
+                     xbt_cfgelm_int, 1, 1, _mc_cfg_cb_max_depth, NULL);
     xbt_cfg_setdefault_int(_sg_cfg_set, "model-check/max_depth", 1000);
 
     /* Set number of visited state stored for state comparison reduction*/
     xbt_cfg_register(&_sg_cfg_set, "model-check/visited",
                      "Specify the number of visited state stored for state comparison reduction. If value=5, the last 5 visited states are stored",
-                     xbt_cfgelm_int, 0, 1, _mc_cfg_cb_visited, NULL);
+                     xbt_cfgelm_int, 1, 1, _mc_cfg_cb_visited, NULL);
     xbt_cfg_setdefault_int(_sg_cfg_set, "model-check/visited", 0);
 
     /* Set file name for dot output of graph state */
     xbt_cfg_register(&_sg_cfg_set, "model-check/dot_output",
                      "Specify the name of dot file corresponding to graph state",
-                     xbt_cfgelm_string, 0, 1, _mc_cfg_cb_dot_output, NULL);
+                     xbt_cfgelm_string, 1, 1, _mc_cfg_cb_dot_output, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "model-check/dot_output", "");
 #endif
 
     /* do verbose-exit */
     xbt_cfg_register(&_sg_cfg_set, "verbose-exit",
                      "Activate the \"do nothing\" mode in Ctrl-C",
-                     xbt_cfgelm_boolean, 0, 1, _sg_cfg_cb_verbose_exit, NULL);
+                     xbt_cfgelm_boolean, 1, 1, _sg_cfg_cb_verbose_exit, NULL);
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "verbose-exit", "yes");
 
     /* context factory */
-    sprintf(description,
-            "Context factory to use in SIMIX. Possible values: thread");
     const char *dflt_ctx_fact = "thread";
+    {
+      char *p = description +
+        sprintf(description,
+                "Context factory to use in SIMIX. Possible values: %s",
+                dflt_ctx_fact);
 #ifdef CONTEXT_UCONTEXT
-    strcat(description, ", ucontext");
-    dflt_ctx_fact = "ucontext";
+      dflt_ctx_fact = "ucontext";
+      p += sprintf(p, ", %s", dflt_ctx_fact);
 #endif
 #ifdef HAVE_RAWCTX
-    strcat(description, ", raw");
-    dflt_ctx_fact = "raw";
+      dflt_ctx_fact = "raw";
+      p += sprintf(p, ", %s", dflt_ctx_fact);
 #endif
-    strcat(description, ".");
+      sprintf(p, ".");
+    }
     xbt_cfg_register(&_sg_cfg_set, "contexts/factory", description,
                      xbt_cfgelm_string, 1, 1, _sg_cfg_cb_context_factory, NULL);
     xbt_cfg_setdefault_string(_sg_cfg_set, "contexts/factory", dflt_ctx_fact);
 
-    /* stack size of contexts in Ko */
+    /* stack size of contexts in KiB */
     xbt_cfg_register(&_sg_cfg_set, "contexts/stack_size",
-                     "Stack size of contexts in Kib",
+                     "Stack size of contexts in KiB",
                      xbt_cfgelm_int, 1, 1, _sg_cfg_cb_context_stack_size, NULL);
-    xbt_cfg_setdefault_int(_sg_cfg_set, "contexts/stack_size", 128);
+    xbt_cfg_setdefault_int(_sg_cfg_set, "contexts/stack_size", 8*1024);
+    /* No, it was not set yet (the above setdefault() changed this to 1). */
+    smx_context_stack_size_was_set = 0;
+
+    /* guard size for contexts stacks in memory pages */
+    xbt_cfg_register(&_sg_cfg_set, "contexts/guard_size",
+                     "Guard size for contexts stacks in memory pages",
+                     xbt_cfgelm_int, 1, 1, _sg_cfg_cb_context_guard_size, NULL);
+    xbt_cfg_setdefault_int(_sg_cfg_set, "contexts/guard_size", 1);
+    /* No, it was not set yet (the above setdefault() changed this to 1). */
+    smx_context_guard_size_was_set = 0;
 
     /* number of parallel threads for user processes */
     xbt_cfg_register(&_sg_cfg_set, "contexts/nthreads",
@@ -653,7 +719,7 @@ void sg_config_init(int *argc, char **argv)
 
     xbt_cfg_register(&_sg_cfg_set, "network/crosstraffic",
                      "Activate the interferences between uploads and downloads for fluid max-min models (LV08, CM02)",
-                     xbt_cfgelm_boolean, 0, 1, _sg_cfg_cb__surf_network_crosstraffic, NULL);
+                     xbt_cfgelm_boolean, 1, 1, _sg_cfg_cb__surf_network_crosstraffic, NULL);
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "network/crosstraffic", "no");
 
 #ifdef HAVE_GTNETS
@@ -691,7 +757,7 @@ void sg_config_init(int *argc, char **argv)
     xbt_cfg_setdefault_boolean(_sg_cfg_set, "smpi/use_shared_malloc", "yes");
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/cpu_threshold",
-                     "Minimal computation time (in seconds) not discarded.",
+                     "Minimal computation time (in seconds) not discarded, or -1 for infinity.",
                      xbt_cfgelm_double, 1, 1, NULL, NULL);
     xbt_cfg_setdefault_double(_sg_cfg_set, "smpi/cpu_threshold", 1e-6);
 
@@ -745,47 +811,47 @@ void sg_config_init(int *argc, char **argv)
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/gather",
                      "Which collective to use for gather",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_gather, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_gather, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/allgather",
                      "Which collective to use for allgather",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_allgather, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_allgather, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/barrier",
                      "Which collective to use for barrier",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_barrier, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_barrier, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/reduce_scatter",
                      "Which collective to use for reduce_scatter",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_reduce_scatter, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_reduce_scatter, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/scatter",
                      "Which collective to use for scatter",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_scatter, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_scatter, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/allgatherv",
                      "Which collective to use for allgatherv",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_allgatherv, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_allgatherv, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/allreduce",
                      "Which collective to use for allreduce",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_allreduce, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_allreduce, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/alltoall",
                      "Which collective to use for alltoall",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_alltoall, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_alltoall, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/alltoallv",
                      "Which collective to use for alltoallv",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_alltoallv, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_alltoallv, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/bcast",
                      "Which collective to use for bcast",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_bcast, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_bcast, NULL);
 
     xbt_cfg_register(&_sg_cfg_set, "smpi/reduce",
                      "Which collective to use for reduce",
-                     xbt_cfgelm_string, 1, 1, &_sg_cfg_cb__coll_reduce, NULL);
+                     xbt_cfgelm_string, 0, 1, &_sg_cfg_cb__coll_reduce, NULL);
 #endif // HAVE_SMPI
 
     xbt_cfg_register(&_sg_cfg_set, "clean_atexit",
@@ -803,6 +869,7 @@ void sg_config_init(int *argc, char **argv)
       xbt_cfg_setdefault_string(_sg_cfg_set, "path", initial_path);
     }
 
+    xbt_cfg_check(_sg_cfg_set);
     _sg_cfg_init_status = 1;
 
     sg_config_cmd_line(argc, argv);
@@ -812,8 +879,6 @@ void sg_config_init(int *argc, char **argv)
   } else {
     XBT_WARN("Call to sg_config_init() after initialization ignored");
   }
-
-  xbt_free(description);
 }
 
 void sg_config_finalize(void)
@@ -829,7 +894,9 @@ void sg_config_finalize(void)
 void surf_config_models_setup()
 {
   const char *workstation_model_name;
+  const char *vm_workstation_model_name;
   int workstation_id = -1;
+  int vm_workstation_id = -1;
   char *network_model_name = NULL;
   char *cpu_model_name = NULL;
   int storage_id = -1;
@@ -837,6 +904,8 @@ void surf_config_models_setup()
 
   workstation_model_name =
       xbt_cfg_get_string(_sg_cfg_set, "workstation/model");
+  vm_workstation_model_name =
+      xbt_cfg_get_string(_sg_cfg_set, "vm_workstation/model");
   network_model_name = xbt_cfg_get_string(_sg_cfg_set, "network/model");
   cpu_model_name = xbt_cfg_get_string(_sg_cfg_set, "cpu/model");
   storage_model_name = xbt_cfg_get_string(_sg_cfg_set, "storage/model");
@@ -881,47 +950,48 @@ void surf_config_models_setup()
   XBT_DEBUG("Call workstation_model_init");
   surf_workstation_model_description[workstation_id].model_init_preparse();
 
+  XBT_DEBUG("Call vm_workstation_model_init");
+  vm_workstation_id = find_model_description(surf_vm_workstation_model_description,
+                                          vm_workstation_model_name);
+  surf_vm_workstation_model_description[vm_workstation_id].model_init_preparse();
+
   XBT_DEBUG("Call storage_model_init");
   storage_id = find_model_description(surf_storage_model_description, storage_model_name);
   surf_storage_model_description[storage_id].model_init_preparse();
 
-  /* ********************************************************************* */
-  /* TUTORIAL: New model                                                   */
-  int new_model_id = -1;
-  char *new_model_name = NULL;
-  new_model_name = xbt_cfg_get_string(_sg_cfg_set, "new_model/model");
-  XBT_DEBUG("Call new model_init");
-  new_model_id = find_model_description(surf_new_model_description, new_model_name);
-  surf_new_model_description[new_model_id].model_init_preparse();
-  /* ********************************************************************* */
+}
+
+int sg_cfg_is_default_value(const char *name)
+{
+  return xbt_cfg_is_default_value(_sg_cfg_set, name);
 }
 
 int sg_cfg_get_int(const char* name)
 {
-  return xbt_cfg_get_int(_sg_cfg_set,name);
+  return xbt_cfg_get_int(_sg_cfg_set, name);
 }
 
 double sg_cfg_get_double(const char* name)
 {
-  return xbt_cfg_get_double(_sg_cfg_set,name);
+  return xbt_cfg_get_double(_sg_cfg_set, name);
 }
 
 char* sg_cfg_get_string(const char* name)
 {
-  return xbt_cfg_get_string(_sg_cfg_set,name);
+  return xbt_cfg_get_string(_sg_cfg_set, name);
 }
 
 int sg_cfg_get_boolean(const char* name)
 {
-  return xbt_cfg_get_boolean(_sg_cfg_set,name);
+  return xbt_cfg_get_boolean(_sg_cfg_set, name);
 }
 
 void sg_cfg_get_peer(const char *name, char **peer, int *port)
 {
-  xbt_cfg_get_peer(_sg_cfg_set,name, peer, port);
+  xbt_cfg_get_peer(_sg_cfg_set, name, peer, port);
 }
 
 xbt_dynar_t sg_cfg_get_dynar(const char* name)
 {
-  return xbt_cfg_get_dynar(_sg_cfg_set,name);
+  return xbt_cfg_get_dynar(_sg_cfg_set, name);
 }