src/surf/sg_platf.cpp

   1 /* Copyright (c) 2006-2014. The SimGrid Team.
   2  * All rights reserved.                                                     */
   3
   4 /* This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the license (GNU LGPL) which comes with this package. */
   6
   7 #include "xbt/misc.h"
   8 #include "xbt/log.h"
   9 #include "xbt/str.h"
  10 #include "xbt/dict.h"
  11 #include "xbt/RngStream.h"
  12 #include "simgrid/platf_interface.h"
  13 #include "surf/surf_routing.h"
  14 #include "surf/surf.h"
  15
  16 #include "src/simix/smx_private.h"
  17
  18 #include "cpu_interface.hpp"
  19 #include "host_interface.hpp"
  20
  21 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(surf_parse);
  22 xbt_dynar_t sg_platf_link_cb_list = NULL;   // of sg_platf_link_cb_t
  23 xbt_dynar_t sg_platf_cluster_cb_list = NULL; // of sg_platf_cluster_cb_t
  24 xbt_dynar_t sg_platf_postparse_cb_list = NULL; // of void_f_void_t
  25
  26 xbt_dynar_t sg_platf_ASroute_cb_list = NULL; // of sg_platf_ASroute_cb_t
  27 xbt_dynar_t sg_platf_bypassRoute_cb_list = NULL; // of sg_platf_bypassRoute_cb_t
  28 xbt_dynar_t sg_platf_bypassASroute_cb_list = NULL; // of sg_platf_bypassASroute_cb_t
  29
  30 xbt_dynar_t sg_platf_trace_cb_list = NULL;
  31 xbt_dynar_t sg_platf_trace_connect_cb_list = NULL;
  32
  33 /* ***************************************** */
  34 /* TUTORIAL: New TAG                         */
  35
  36 xbt_dynar_t sg_platf_gpu_cb_list = NULL;
  37 /* ***************************************** */
  38
  39
  40 static int surf_parse_models_setup_already_called = 0;
  41
  42 /* one RngStream for the platform, to respect some statistic rules */
  43 static RngStream sg_platf_rng_stream = NULL;
  44
  45 /** Module management function: creates all internal data structures */
  46 void sg_platf_init(void) {
  47
  48   //FIXME : Ugly, but useful...
  49   if (sg_platf_gpu_cb_list)
  50     return; //Already initialized, so do nothing...
  51
  52   sg_platf_link_cb_list = xbt_dynar_new(sizeof(sg_platf_link_cb_t), NULL);
  53   sg_platf_cluster_cb_list = xbt_dynar_new(sizeof(sg_platf_cluster_cb_t), NULL);
  54   sg_platf_postparse_cb_list = xbt_dynar_new(sizeof(sg_platf_link_cb_t),NULL);
  55
  56   sg_platf_ASroute_cb_list = xbt_dynar_new(sizeof(sg_platf_route_cb_t), NULL);
  57   sg_platf_bypassRoute_cb_list = xbt_dynar_new(sizeof(sg_platf_route_cb_t), NULL);
  58   sg_platf_bypassASroute_cb_list = xbt_dynar_new(sizeof(sg_platf_route_cb_t), NULL);
  59
  60   sg_platf_trace_cb_list = xbt_dynar_new(sizeof(sg_platf_trace_cb_t), NULL);
  61   sg_platf_trace_connect_cb_list = xbt_dynar_new(sizeof(sg_platf_trace_connect_cb_t), NULL);
  62
  63   /* ***************************************** */
  64   /* TUTORIAL: New TAG                         */
  65
  66   sg_platf_gpu_cb_list = xbt_dynar_new(sizeof(sg_platf_gpu_cb_t), NULL);
  67   /* ***************************************** */
  68 }
  69 /** Module management function: frees all internal data structures */
  70 void sg_platf_exit(void) {
  71   xbt_dynar_free(&sg_platf_link_cb_list);
  72   xbt_dynar_free(&sg_platf_postparse_cb_list);
  73   xbt_dynar_free(&sg_platf_cluster_cb_list);
  74
  75   xbt_dynar_free(&sg_platf_trace_cb_list);
  76   xbt_dynar_free(&sg_platf_trace_connect_cb_list);
  77
  78   xbt_dynar_free(&sg_platf_ASroute_cb_list);
  79   xbt_dynar_free(&sg_platf_bypassRoute_cb_list);
  80   xbt_dynar_free(&sg_platf_bypassASroute_cb_list);
  81
  82   /* ***************************************** */
  83   /* TUTORIAL: New TAG                         */
  84
  85   xbt_dynar_free(&sg_platf_gpu_cb_list);
  86
  87   /* ***************************************** */
  88
  89   /* make sure that we will reinit the models while loading the platf once reinited */
  90   surf_parse_models_setup_already_called = 0;
  91 }
  92
  93 void sg_platf_new_host(sg_platf_host_cbarg_t host)
  94 {
  95   xbt_assert(! sg_host_by_name(host->id),
  96                      "Refusing to create a second host named '%s'.", host->id);
  97
  98   RoutingEdge *net = NULL;
  99   As* current_routing = routing_get_current();
 100   if (current_routing)
 101     net = routing_add_host(current_routing, host);
 102
 103   Cpu *cpu = surf_cpu_model_pm->createCpu(
 104         host->id,
 105         host->power_peak,
 106         host->pstate,
 107         host->power_scale,
 108         host->power_trace,
 109         host->core_amount,
 110         host->initial_state,
 111         host->state_trace,
 112         host->properties);
 113   surf_host_model->createHost(host->id, net, cpu);
 114
 115   if (TRACE_is_enabled() && TRACE_needs_platform())
 116     sg_instr_new_host(host);
 117 }
 118
 119 /**
 120  * \brief Add a "router" to the network element list
 121  */
 122 void sg_platf_new_router(sg_platf_router_cbarg_t router)
 123 {
 124   As* current_routing = routing_get_current();
 125
 126   if (current_routing->p_hierarchy == SURF_ROUTING_NULL)
 127     current_routing->p_hierarchy = SURF_ROUTING_BASE;
 128   xbt_assert(!xbt_lib_get_or_null(as_router_lib, router->id, ROUTING_ASR_LEVEL),
 129              "Reading a router, processing unit \"%s\" already exists",
 130              router->id);
 131
 132   RoutingEdge *info = new RoutingEdgeImpl(xbt_strdup(router->id),
 133                                             -1,
 134                                             SURF_NETWORK_ELEMENT_ROUTER,
 135                                             current_routing);
 136   info->setId(current_routing->parsePU(info));
 137   xbt_lib_set(as_router_lib, router->id, ROUTING_ASR_LEVEL, (void *) info);
 138   XBT_DEBUG("Having set name '%s' id '%d'", router->id, info->getId());
 139   routingEdgeCreatedCallbacks(info);
 140
 141   if (router->coord && strcmp(router->coord, "")) {
 142     unsigned int cursor;
 143     char*str;
 144
 145     if (!COORD_ASR_LEVEL)
 146       xbt_die ("To use host coordinates, please add --cfg=network/coordinates:yes to your command line");
 147     /* Pre-parse the host coordinates */
 148     xbt_dynar_t ctn_str = xbt_str_split_str(router->coord, " ");
 149     xbt_dynar_t ctn = xbt_dynar_new(sizeof(double),NULL);
 150     xbt_dynar_foreach(ctn_str,cursor, str) {
 151       double val = atof(str);
 152       xbt_dynar_push(ctn,&val);
 153     }
 154     xbt_dynar_shrink(ctn, 0);
 155     xbt_dynar_free(&ctn_str);
 156     xbt_lib_set(as_router_lib, router->id, COORD_ASR_LEVEL, (void *) ctn);
 157     XBT_DEBUG("Having set router coordinates for '%s'",router->id);
 158   }
 159
 160   if (TRACE_is_enabled())
 161     sg_instr_new_router(router);
 162 }
 163
 164 void sg_platf_new_link(sg_platf_link_cbarg_t link){
 165   unsigned int iterator;
 166   sg_platf_link_cb_t fun;
 167   xbt_dynar_foreach(sg_platf_link_cb_list, iterator, fun) {
 168     fun(link);
 169   }
 170 }
 171
 172 void sg_platf_new_cluster(sg_platf_cluster_cbarg_t cluster){
 173   unsigned int iterator;
 174   sg_platf_cluster_cb_t fun;
 175   xbt_dynar_foreach(sg_platf_cluster_cb_list, iterator, fun) {
 176     fun(cluster);
 177   }
 178 }
 179
 180 void sg_platf_new_storage(sg_platf_storage_cbarg_t storage)
 181 {
 182   xbt_assert(!xbt_lib_get_or_null(storage_lib, storage->id,ROUTING_STORAGE_LEVEL),
 183                "Reading a storage, processing unit \"%s\" already exists", storage->id);
 184
 185   // Verification of an existing type_id
 186 #ifndef NDEBUG
 187   void* storage_type = xbt_lib_get_or_null(storage_type_lib, storage->type_id,ROUTING_STORAGE_TYPE_LEVEL);
 188 #endif
 189   xbt_assert(storage_type,"Reading a storage, type id \"%s\" does not exists", storage->type_id);
 190
 191   XBT_DEBUG("ROUTING Create a storage name '%s' with type_id '%s' and content '%s'",
 192       storage->id,
 193       storage->type_id,
 194       storage->content);
 195
 196   xbt_lib_set(storage_lib,
 197       storage->id,
 198       ROUTING_STORAGE_LEVEL,
 199       (void *) xbt_strdup(storage->type_id));
 200
 201   void* stype = xbt_lib_get_or_null(storage_type_lib,
 202                                     storage->type_id,
 203                                     ROUTING_STORAGE_TYPE_LEVEL);
 204   if(!stype) xbt_die("No storage type '%s'",storage->type_id);
 205
 206   // if storage content is not specified use the content of storage_type if exist
 207   if(!strcmp(storage->content,"") && strcmp(((storage_type_t) stype)->content,"")){
 208     storage->content = ((storage_type_t) stype)->content;
 209     storage->content_type = ((storage_type_t) stype)->content_type;
 210     XBT_DEBUG("For disk '%s' content is empty, inherit the content (of type %s) from storage type '%s' ",
 211         storage->id,((storage_type_t) stype)->content_type,
 212         ((storage_type_t) stype)->type_id);
 213   }
 214
 215   XBT_DEBUG("SURF storage create resource\n\t\tid '%s'\n\t\ttype '%s' "
 216       "\n\t\tmodel '%s' \n\t\tcontent '%s'\n\t\tcontent_type '%s' "
 217       "\n\t\tproperties '%p''\n",
 218       storage->id,
 219       ((storage_type_t) stype)->model,
 220       ((storage_type_t) stype)->type_id,
 221       storage->content,
 222       storage->content_type,
 223       storage->properties);
 224
 225   surf_storage_model->createStorage(storage->id,
 226                                      ((storage_type_t) stype)->type_id,
 227                                      storage->content,
 228                                      storage->content_type,
 229                                      storage->properties,
 230                                      storage->attach);
 231 }
 232 void sg_platf_new_storage_type(sg_platf_storage_type_cbarg_t storage_type){
 233
 234   xbt_assert(!xbt_lib_get_or_null(storage_type_lib, storage_type->id,ROUTING_STORAGE_TYPE_LEVEL),
 235                "Reading a storage type, processing unit \"%s\" already exists", storage_type->id);
 236
 237   storage_type_t stype = xbt_new0(s_storage_type_t, 1);
 238   stype->model = xbt_strdup(storage_type->model);
 239   stype->properties = storage_type->properties;
 240   stype->content = xbt_strdup(storage_type->content);
 241   stype->content_type = xbt_strdup(storage_type->content_type);
 242   stype->type_id = xbt_strdup(storage_type->id);
 243   stype->size = storage_type->size;
 244   stype->model_properties = storage_type->model_properties;
 245
 246   XBT_DEBUG("ROUTING Create a storage type id '%s' with model '%s', "
 247       "content '%s', and content_type '%s'",
 248       stype->type_id,
 249       stype->model,
 250       storage_type->content,
 251       storage_type->content_type);
 252
 253   xbt_lib_set(storage_type_lib,
 254       stype->type_id,
 255       ROUTING_STORAGE_TYPE_LEVEL,
 256       (void *) stype);
 257 }
 258 void sg_platf_new_mstorage(sg_platf_mstorage_cbarg_t mstorage)
 259 {
 260   THROW_UNIMPLEMENTED;
 261 //  mount_t mnt = xbt_new0(s_mount_t, 1);
 262 //  mnt->id = xbt_strdup(mstorage->type_id);
 263 //  mnt->name = xbt_strdup(mstorage->name);
 264 //
 265 //  if(!mount_list){
 266 //    XBT_DEBUG("Creata a Mount list for %s",A_surfxml_host_id);
 267 //    mount_list = xbt_dynar_new(sizeof(char *), NULL);
 268 //  }
 269 //  xbt_dynar_push(mount_list,(void *) mnt);
 270 //  free(mnt->id);
 271 //  free(mnt->name);
 272 //  xbt_free(mnt);
 273 //  XBT_DEBUG("ROUTING Mount a storage name '%s' with type_id '%s'",mstorage->name, mstorage->id);
 274 }
 275
 276 static void mount_free(void *p)
 277 {
 278   mount_t mnt = (mount_t) p;
 279   xbt_free(mnt->name);
 280 }
 281
 282 void sg_platf_new_mount(sg_platf_mount_cbarg_t mount){
 283   // Verification of an existing storage
 284 #ifndef NDEBUG
 285   void* storage = xbt_lib_get_or_null(storage_lib, mount->storageId, ROUTING_STORAGE_LEVEL);
 286 #endif
 287   xbt_assert(storage,"Disk id \"%s\" does not exists", mount->storageId);
 288
 289   XBT_DEBUG("ROUTING Mount '%s' on '%s'",mount->storageId, mount->name);
 290
 291   s_mount_t mnt;
 292   mnt.storage = surf_storage_resource_priv(surf_storage_resource_by_name(mount->storageId));
 293   mnt.name = xbt_strdup(mount->name);
 294
 295   if(!mount_list){
 296     XBT_DEBUG("Create a Mount list for %s",A_surfxml_host_id);
 297     mount_list = xbt_dynar_new(sizeof(s_mount_t), mount_free);
 298   }
 299   xbt_dynar_push(mount_list, &mnt);
 300 }
 301
 302 void sg_platf_new_route(sg_platf_route_cbarg_t route)
 303 {
 304   routing_get_current()->parseRoute(route);
 305 }
 306
 307 void sg_platf_new_ASroute(sg_platf_route_cbarg_t ASroute) {
 308   unsigned int iterator;
 309   sg_platf_route_cb_t fun;
 310   xbt_dynar_foreach(sg_platf_ASroute_cb_list, iterator, fun) {
 311     fun(ASroute);
 312   }
 313 }
 314 void sg_platf_new_bypassRoute(sg_platf_route_cbarg_t bypassRoute) {
 315   unsigned int iterator;
 316   sg_platf_route_cb_t fun;
 317   xbt_dynar_foreach(sg_platf_bypassRoute_cb_list, iterator, fun) {
 318     fun(bypassRoute);
 319   }
 320 }
 321 void sg_platf_new_bypassASroute(sg_platf_route_cbarg_t bypassASroute) {
 322   unsigned int iterator;
 323   sg_platf_route_cb_t fun;
 324   xbt_dynar_foreach(sg_platf_bypassASroute_cb_list, iterator, fun) {
 325     fun(bypassASroute);
 326   }
 327 }
 328 void sg_platf_new_trace(sg_platf_trace_cbarg_t trace) {
 329   unsigned int iterator;
 330   sg_platf_trace_cb_t fun;
 331   xbt_dynar_foreach(sg_platf_trace_cb_list, iterator, fun) {
 332     fun(trace);
 333   }
 334 }
 335 void sg_platf_trace_connect(sg_platf_trace_connect_cbarg_t trace_connect) {
 336   unsigned int iterator;
 337   sg_platf_trace_connect_cb_t fun;
 338   xbt_dynar_foreach(sg_platf_trace_connect_cb_list, iterator, fun) {
 339     fun(trace_connect);
 340   }
 341 }
 342
 343 void sg_platf_new_process(sg_platf_process_cbarg_t process)
 344 {
 345   if (!simix_global)
 346     xbt_die("Cannot create process without SIMIX.");
 347
 348   sg_host_t host = sg_host_by_name(process->host);
 349   if (!host)
 350     THROWF(arg_error, 0, "Host '%s' unknown", process->host);
 351   xbt_main_func_t parse_code = SIMIX_get_registered_function(process->function);
 352   xbt_assert(parse_code, "Function '%s' unknown", process->function);
 353
 354   double start_time = process->start_time;
 355   double kill_time  = process->kill_time;
 356   int auto_restart = process->on_failure == SURF_PROCESS_ON_FAILURE_DIE ? 0 : 1;
 357
 358   smx_process_arg_t arg = NULL;
 359   smx_process_t process_created = NULL;
 360
 361   arg = xbt_new0(s_smx_process_arg_t, 1);
 362   arg->code = parse_code;
 363   arg->data = NULL;
 364   arg->hostname = sg_host_get_name(host);
 365   arg->argc = process->argc;
 366   arg->argv = xbt_new(char *,process->argc);
 367   int i;
 368   for (i=0; i<process->argc; i++)
 369     arg->argv[i] = xbt_strdup(process->argv[i]);
 370   arg->name = xbt_strdup(arg->argv[0]);
 371   arg->kill_time = kill_time;
 372   arg->properties = current_property_set;
 373   if (!sg_host_simix(host)->boot_processes) {
 374     sg_host_simix(host)->boot_processes = xbt_dynar_new(sizeof(smx_process_arg_t), _SIMIX_host_free_process_arg);
 375   }
 376   xbt_dynar_push_as(sg_host_simix(host)->boot_processes,smx_process_arg_t,arg);
 377
 378   if (start_time > SIMIX_get_clock()) {
 379     arg = xbt_new0(s_smx_process_arg_t, 1);
 380     arg->name = (char*)(process->argv)[0];
 381     arg->code = parse_code;
 382     arg->data = NULL;
 383     arg->hostname = sg_host_get_name(host);
 384     arg->argc = process->argc;
 385     arg->argv = (char**)(process->argv);
 386     arg->kill_time = kill_time;
 387     arg->properties = current_property_set;
 388
 389     XBT_DEBUG("Process %s(%s) will be started at time %f", arg->name,
 390            arg->hostname, start_time);
 391     SIMIX_timer_set(start_time, [](void* arg) {
 392       SIMIX_process_create_from_wrapper((smx_process_arg_t) arg);
 393     }, arg);
 394   } else {                      // start_time <= SIMIX_get_clock()
 395     XBT_DEBUG("Starting Process %s(%s) right now", process->argv[0], sg_host_get_name(host));
 396
 397     if (simix_global->create_process_function)
 398       process_created = simix_global->create_process_function(
 399                                             (char*)(process->argv)[0],
 400                                             parse_code,
 401                                             NULL,
 402                                             sg_host_get_name(host),
 403                                             kill_time,
 404                                             process->argc,
 405                                             (char**)(process->argv),
 406                                             current_property_set,
 407                                             auto_restart, NULL);
 408     else
 409       process_created = simcall_process_create((char*)(process->argv)[0], parse_code, NULL, sg_host_get_name(host), kill_time, process->argc,
 410           (char**)process->argv, current_property_set,auto_restart);
 411
 412     /* verify if process has been created (won't be the case if the host is currently dead, but that's fine) */
 413     if (!process_created) {
 414       return;
 415     }
 416   }
 417   current_property_set = NULL;
 418 }
 419
 420 void sg_platf_route_begin (sg_platf_route_cbarg_t route){
 421   route->link_list = xbt_dynar_new(sizeof(char *), &xbt_free_ref);
 422 }
 423 void sg_platf_ASroute_begin (sg_platf_route_cbarg_t ASroute){
 424   ASroute->link_list = xbt_dynar_new(sizeof(char *), &xbt_free_ref);
 425 }
 426
 427 void sg_platf_route_end (sg_platf_route_cbarg_t route){
 428   sg_platf_new_route(route);
 429 }
 430 void sg_platf_ASroute_end (sg_platf_route_cbarg_t ASroute){
 431   sg_platf_new_ASroute(ASroute);
 432 }
 433
 434 void sg_platf_route_add_link (const char* link_id, sg_platf_route_cbarg_t route){
 435   char *link_name = xbt_strdup(link_id);
 436   xbt_dynar_push(route->link_list, &link_name);
 437 }
 438 void sg_platf_ASroute_add_link (const char* link_id, sg_platf_route_cbarg_t ASroute){
 439   char *link_name = xbt_strdup(link_id);
 440   xbt_dynar_push(ASroute->link_list, &link_name);
 441 }
 442
 443 void sg_platf_begin() { /* Do nothing: just for symmetry of user code */ }
 444
 445 void sg_platf_end() {
 446   unsigned int iterator;
 447   void_f_void_t fun;
 448   xbt_dynar_foreach(sg_platf_postparse_cb_list, iterator, fun) {
 449     fun();
 450   }
 451 }
 452
 453 void sg_platf_new_AS_begin(sg_platf_AS_cbarg_t AS)
 454 {
 455   if (!surf_parse_models_setup_already_called) {
 456     /* Initialize the surf models. That must be done after we got all config, and before we need the models.
 457      * That is, after the last <config> tag, if any, and before the first of cluster|peer|AS|trace|trace_connect
 458      *
 459      * I'm not sure for <trace> and <trace_connect>, there may be a bug here
 460      * (FIXME: check it out by creating a file beginning with one of these tags)
 461      * but cluster and peer create ASes internally, so putting the code in there is ok.
 462      *
 463      * TODO, There used to be a guard protecting here against
 464      * xbt_dynar_length(sg_platf_AS_begin_cb_list) because we don't want to
 465      * initialize the models if we are parsing the file to get the deployment.
 466      * That could happen if the same file would be used for platf and deploy:
 467      * it'd contain AS tags even during the deploy parsing. Removing that guard
 468      * would result of the models to get re-inited when parsing for deploy.
 469      * Currently using the same file for platform and deployment is broken
 470      * however. This guard will have to ba adapted in order to make this feature
 471      * work again.
 472      */
 473     surf_parse_models_setup_already_called = 1;
 474     surf_config_models_setup();
 475   }
 476
 477   routing_AS_begin(AS);
 478   if (TRACE_is_enabled())
 479     sg_instr_AS_begin(AS);
 480 }
 481
 482 void sg_platf_new_AS_end()
 483 {
 484   routing_AS_end();
 485   if (TRACE_is_enabled())
 486     sg_instr_AS_end();
 487 }
 488
 489 /* ***************************************** */
 490 /* TUTORIAL: New TAG                         */
 491
 492 void sg_platf_new_gpu(sg_platf_gpu_cbarg_t gpu) {
 493   unsigned int iterator;
 494   void_f_void_t fun;
 495   xbt_dynar_foreach(sg_platf_gpu_cb_list, iterator, fun) {
 496     fun();
 497   }
 498 }
 499
 500 void sg_platf_gpu_add_cb(sg_platf_gpu_cb_t fct) {
 501   xbt_dynar_push(sg_platf_gpu_cb_list, &fct);
 502 }
 503
 504 /* ***************************************** */
 505
 506 void sg_platf_link_add_cb(sg_platf_link_cb_t fct) {
 507   xbt_dynar_push(sg_platf_link_cb_list, &fct);
 508 }
 509 void sg_platf_cluster_add_cb(sg_platf_cluster_cb_t fct) {
 510   xbt_dynar_push(sg_platf_cluster_cb_list, &fct);
 511 }
 512 void sg_platf_postparse_add_cb(void_f_void_t fct) {
 513   xbt_dynar_push(sg_platf_postparse_cb_list, &fct);
 514 }
 515 void sg_platf_ASroute_add_cb(sg_platf_route_cb_t fct) {
 516   xbt_dynar_push(sg_platf_ASroute_cb_list, &fct);
 517 }
 518 void sg_platf_bypassRoute_add_cb(sg_platf_route_cb_t fct) {
 519   xbt_dynar_push(sg_platf_bypassRoute_cb_list, &fct);
 520 }
 521 void sg_platf_bypassASroute_add_cb(sg_platf_route_cb_t fct) {
 522   xbt_dynar_push(sg_platf_bypassASroute_cb_list, &fct);
 523 }
 524 void sg_platf_trace_add_cb(sg_platf_trace_cb_t fct) {
 525   xbt_dynar_push(sg_platf_trace_cb_list, &fct);
 526 }
 527 void sg_platf_trace_connect_add_cb(sg_platf_trace_connect_cb_t fct) {
 528   xbt_dynar_push(sg_platf_trace_connect_cb_list, &fct);
 529 }
 530 void sg_platf_rng_stream_init(unsigned long seed[6]) {
 531   RngStream_SetPackageSeed(seed);
 532   sg_platf_rng_stream = RngStream_CreateStream(NULL);
 533 }
 534
 535 RngStream sg_platf_rng_stream_get(const char* id) {
 536   RngStream stream = NULL;
 537   unsigned int id_hash;
 538
 539   stream = RngStream_CopyStream(sg_platf_rng_stream);
 540   id_hash = xbt_str_hash(id);
 541   RngStream_AdvanceState(stream, 0, (long)id_hash);
 542
 543   return stream;
 544 }