src/simdag/sd_workstation.c

   1 /* Copyright (c) 2006-2011. 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 "private.h"
   8 #include "simdag/simdag.h"
   9 #include "xbt/dict.h"
  10 #include "xbt/sysdep.h"
  11 #include "surf/surf.h"
  12 #include "surf/surf_resource.h"
  13
  14
  15
  16 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(sd_workstation, sd,
  17                                 "Logging specific to SimDag (workstation)");
  18
  19 /* Creates a workstation and registers it in SD.
  20  */
  21 SD_workstation_t __SD_workstation_create(void *surf_workstation,
  22                                          void *data)
  23 {
  24
  25   SD_workstation_t workstation;
  26   const char *name;
  27
  28   workstation = xbt_new(s_SD_workstation_t, 1);
  29   workstation->surf_workstation = surf_workstation;
  30   workstation->data = data;     /* user data */
  31   workstation->access_mode = SD_WORKSTATION_SHARED_ACCESS;      /* default mode is shared */
  32   workstation->task_fifo = NULL;
  33   workstation->current_task = NULL;
  34
  35   name = SD_workstation_get_name(workstation);
  36   xbt_lib_set(host_lib,name,SD_HOST_LEVEL,workstation);
  37   return workstation;
  38 }
  39
  40 /**
  41  * \brief Returns a workstation given its name
  42  *
  43  * If there is no such workstation, the function returns \c NULL.
  44  *
  45  * \param name workstation name
  46  * \return the workstation, or \c NULL if there is no such workstation
  47  */
  48 SD_workstation_t SD_workstation_get_by_name(const char *name)
  49 {
  50   return xbt_lib_get_or_null(host_lib, name, SD_HOST_LEVEL);
  51 }
  52
  53 /**
  54  * \brief Returns the workstation list
  55  *
  56  * Use SD_workstation_get_number() to know the array size.
  57  *
  58  * \return an array of \ref SD_workstation_t containing all workstations
  59  * \see SD_workstation_get_number()
  60  */
  61 const SD_workstation_t *SD_workstation_get_list(void)
  62 {
  63
  64   xbt_lib_cursor_t cursor;
  65   char *key;
  66   void **data;
  67   int i;
  68
  69   xbt_assert(SD_workstation_get_number() > 0, "There is no workstation!");
  70
  71   if (sd_global->workstation_list == NULL) {    /* this is the first time the function is called */
  72     sd_global->workstation_list =
  73       xbt_new(SD_workstation_t, xbt_lib_length(host_lib));
  74
  75     i = 0;
  76     xbt_lib_foreach(host_lib, cursor, key, data) {
  77       if(data[SD_HOST_LEVEL])
  78         sd_global->workstation_list[i++] = (SD_workstation_t) data[SD_HOST_LEVEL];
  79     }
  80   }
  81   return sd_global->workstation_list;
  82 }
  83
  84 /**
  85  * \brief Returns the number of workstations
  86  *
  87  * \return the number of existing workstations
  88  * \see SD_workstation_get_list()
  89  */
  90 int SD_workstation_get_number(void)
  91 {
  92   return xbt_lib_length(host_lib);
  93 }
  94
  95 /**
  96  * \brief Returns the user data of a workstation
  97  *
  98  * \param workstation a workstation
  99  * \return the user data associated with this workstation (can be \c NULL)
 100  * \see SD_workstation_set_data()
 101  */
 102 void *SD_workstation_get_data(SD_workstation_t workstation)
 103 {
 104   return workstation->data;
 105 }
 106
 107 /**
 108  * \brief Sets the user data of a workstation
 109  *
 110  * The new data can be \c NULL. The old data should have been freed first
 111  * if it was not \c NULL.
 112  *
 113  * \param workstation a workstation
 114  * \param data the new data you want to associate with this workstation
 115  * \see SD_workstation_get_data()
 116  */
 117 void SD_workstation_set_data(SD_workstation_t workstation, void *data)
 118 {
 119   workstation->data = data;
 120 }
 121
 122 /**
 123  * \brief Returns the name of a workstation
 124  *
 125  * \param workstation a workstation
 126  * \return the name of this workstation (cannot be \c NULL)
 127  */
 128 const char *SD_workstation_get_name(SD_workstation_t workstation)
 129 {
 130   return surf_resource_name(workstation->surf_workstation);
 131 }
 132
 133 /**
 134  * \brief Returns the value of a given workstation property
 135  *
 136  * \param ws a workstation
 137  * \param name a property name
 138  * \return value of a property (or NULL if property not set)
 139  */
 140 const char *SD_workstation_get_property_value(SD_workstation_t ws,
 141                                               const char *name)
 142 {
 143   return xbt_dict_get_or_null(SD_workstation_get_properties(ws), name);
 144 }
 145
 146
 147 /**
 148  * \brief Returns a #xbt_dict_t consisting of the list of properties assigned to this workstation
 149  *
 150  * \param workstation a workstation
 151  * \return the dictionary containing the properties associated with the workstation
 152  */
 153 xbt_dict_t SD_workstation_get_properties(SD_workstation_t workstation)
 154 {
 155   return surf_workstation_model->extension.
 156       workstation.get_properties(workstation->surf_workstation);
 157
 158 }
 159
 160 /** @brief Displays debugging informations about a workstation */
 161 void SD_workstation_dump(SD_workstation_t ws)
 162 {
 163   xbt_dict_t props;
 164   xbt_dict_cursor_t cursor=NULL;
 165   char *key,*data;
 166   SD_task_t task = NULL;
 167
 168   XBT_INFO("Displaying workstation %s", SD_workstation_get_name(ws));
 169   XBT_INFO("  - power: %.0f", SD_workstation_get_power(ws));
 170   XBT_INFO("  - available power: %.2f", SD_workstation_get_available_power(ws));
 171   switch (ws->access_mode){
 172   case SD_WORKSTATION_SHARED_ACCESS:
 173       XBT_INFO("  - access mode: Space shared");
 174       break;
 175   case SD_WORKSTATION_SEQUENTIAL_ACCESS:
 176       XBT_INFO("  - access mode: Exclusive");
 177     task = SD_workstation_get_current_task(ws);
 178     if(task)
 179       XBT_INFO("    current running task: %s",
 180                SD_task_get_name(task));
 181     else
 182       XBT_INFO("    no task running");
 183       break;
 184   default:
 185       XBT_INFO("  - (unknown access mode)");
 186   }
 187   props = SD_workstation_get_properties(ws);
 188
 189   if (!xbt_dict_is_empty(props)){
 190     XBT_INFO("  - properties:");
 191
 192     xbt_dict_foreach(props,cursor,key,data) {
 193       XBT_INFO("    %s->%s",key,data);
 194     }
 195   }
 196 }
 197
 198 /**
 199  * \brief Returns the route between two workstations
 200  *
 201  * Use SD_route_get_size() to know the array size.
 202  *
 203  * \param src a workstation
 204  * \param dst another workstation
 205  * \return a new array of \ref SD_link_t representating the route between these two workstations
 206  * \see SD_route_get_size(), SD_link_t
 207  */
 208 const SD_link_t *SD_route_get_list(SD_workstation_t src,
 209                                    SD_workstation_t dst)
 210 {
 211   void *surf_src;
 212   void *surf_dst;
 213   xbt_dynar_t surf_route;
 214   const char *link_name;
 215   void *surf_link;
 216   unsigned int cpt;
 217
 218   if (sd_global->recyclable_route == NULL) {
 219     /* first run */
 220     sd_global->recyclable_route = xbt_new(SD_link_t, SD_link_get_number());
 221   }
 222
 223   surf_src = src->surf_workstation;
 224   surf_dst = dst->surf_workstation;
 225   surf_route =
 226       surf_workstation_model->extension.workstation.get_route(surf_src,
 227                                                               surf_dst);
 228
 229   xbt_dynar_foreach(surf_route, cpt, surf_link) {
 230     link_name = surf_resource_name(surf_link);
 231     sd_global->recyclable_route[cpt] =
 232         xbt_lib_get_or_null(link_lib, link_name, SD_LINK_LEVEL);
 233   }
 234   return sd_global->recyclable_route;
 235 }
 236
 237 /**
 238  * \brief Returns the number of links on the route between two workstations
 239  *
 240  * \param src a workstation
 241  * \param dst another workstation
 242  * \return the number of links on the route between these two workstations
 243  * \see SD_route_get_list()
 244  */
 245 int SD_route_get_size(SD_workstation_t src, SD_workstation_t dst)
 246 {
 247   return xbt_dynar_length(surf_workstation_model->extension.
 248                           workstation.get_route(src->surf_workstation,
 249                                                 dst->surf_workstation));
 250 }
 251
 252 /**
 253  * \brief Returns the total power of a workstation
 254  *
 255  * \param workstation a workstation
 256  * \return the total power of this workstation
 257  * \see SD_workstation_get_available_power()
 258  */
 259 double SD_workstation_get_power(SD_workstation_t workstation)
 260 {
 261   return surf_workstation_model->extension.workstation.
 262       get_speed(workstation->surf_workstation, 1.0);
 263 }
 264
 265 /**
 266  * \brief Returns the proportion of available power in a workstation
 267  *
 268  * \param workstation a workstation
 269  * \return the proportion of power currently available in this workstation (normally a number between 0 and 1)
 270  * \see SD_workstation_get_power()
 271  */
 272 double SD_workstation_get_available_power(SD_workstation_t workstation)
 273 {
 274   return surf_workstation_model->extension.
 275       workstation.get_available_speed(workstation->surf_workstation);
 276 }
 277
 278 /**
 279  * \brief Returns an approximative estimated time for the given computation amount on a workstation
 280  *
 281  * \param workstation a workstation
 282  * \param computation_amount the computation amount you want to evaluate (in flops)
 283  * \return an approximative astimated computation time for the given computation amount on this workstation (in seconds)
 284  */
 285 double SD_workstation_get_computation_time(SD_workstation_t workstation,
 286                                            double computation_amount)
 287 {
 288   xbt_assert(computation_amount >= 0,
 289               "computation_amount must be greater than or equal to zero");
 290   return computation_amount / SD_workstation_get_power(workstation);
 291 }
 292
 293 /**
 294  * \brief Returns the latency of the route between two workstations, i.e. the sum of all link latencies
 295  * between the workstations.
 296  *
 297  * \param src the first workstation
 298  * \param dst the second workstation
 299  * \return the latency of the route between the two workstations (in seconds)
 300  * \see SD_route_get_current_bandwidth()
 301  */
 302 double SD_route_get_current_latency(SD_workstation_t src,
 303                                     SD_workstation_t dst)
 304 {
 305
 306   const SD_link_t *links;
 307   int nb_links;
 308   double latency;
 309   int i;
 310
 311   links = SD_route_get_list(src, dst);
 312   nb_links = SD_route_get_size(src, dst);
 313   latency = 0.0;
 314
 315   for (i = 0; i < nb_links; i++) {
 316     latency += SD_link_get_current_latency(links[i]);
 317   }
 318
 319   return latency;
 320 }
 321
 322 /**
 323  * \brief Returns the bandwidth of the route between two workstations, i.e. the minimum link bandwidth of all
 324  * between the workstations.
 325  *
 326  * \param src the first workstation
 327  * \param dst the second workstation
 328  * \return the bandwidth of the route between the two workstations (in bytes/second)
 329  * \see SD_route_get_current_latency()
 330  */
 331 double SD_route_get_current_bandwidth(SD_workstation_t src,
 332                                       SD_workstation_t dst)
 333 {
 334
 335   const SD_link_t *links;
 336   int nb_links;
 337   double bandwidth;
 338   double min_bandwidth;
 339   int i;
 340
 341   links = SD_route_get_list(src, dst);
 342   nb_links = SD_route_get_size(src, dst);
 343   bandwidth = min_bandwidth = -1.0;
 344
 345
 346   for (i = 0; i < nb_links; i++) {
 347     bandwidth = SD_link_get_current_bandwidth(links[i]);
 348     if (bandwidth < min_bandwidth || min_bandwidth == -1.0)
 349       min_bandwidth = bandwidth;
 350   }
 351
 352   return min_bandwidth;
 353 }
 354
 355 /**
 356  * \brief Returns an approximative estimated time for the given
 357  * communication amount between two workstations
 358  *
 359  * \param src the first workstation
 360  * \param dst the second workstation
 361  * \param communication_amount the communication amount you want to evaluate (in bytes)
 362  * \return an approximative astimated computation time for the given communication amount
 363  * between the workstations (in seconds)
 364  */
 365 double SD_route_get_communication_time(SD_workstation_t src,
 366                                        SD_workstation_t dst,
 367                                        double communication_amount)
 368 {
 369
 370
 371   /* total time = latency + transmission time of the slowest link
 372      transmission time of a link = communication amount / link bandwidth */
 373
 374   const SD_link_t *links;
 375   int nb_links;
 376   double bandwidth, min_bandwidth;
 377   double latency;
 378   int i;
 379
 380   xbt_assert(communication_amount >= 0,
 381               "communication_amount must be greater than or equal to zero");
 382
 383
 384
 385   if (communication_amount == 0.0)
 386     return 0.0;
 387
 388   links = SD_route_get_list(src, dst);
 389   nb_links = SD_route_get_size(src, dst);
 390   min_bandwidth = -1.0;
 391   latency = 0;
 392
 393   for (i = 0; i < nb_links; i++) {
 394     latency += SD_link_get_current_latency(links[i]);
 395     bandwidth = SD_link_get_current_bandwidth(links[i]);
 396     if (bandwidth < min_bandwidth || min_bandwidth == -1.0)
 397       min_bandwidth = bandwidth;
 398   }
 399
 400   return latency + (communication_amount / min_bandwidth);
 401 }
 402
 403 /**
 404  * \brief Returns the access mode of this workstation.
 405  *
 406  * \param workstation a workstation
 407  * \return the access mode for the tasks running on this workstation:
 408  * SD_WORKSTATION_SHARED_ACCESS or SD_WORKSTATION_SEQUENTIAL_ACCESS
 409  *
 410  * \see SD_workstation_set_access_mode(), e_SD_workstation_access_mode_t
 411  */
 412 e_SD_workstation_access_mode_t
 413 SD_workstation_get_access_mode(SD_workstation_t workstation)
 414 {
 415   return workstation->access_mode;
 416 }
 417
 418 /**
 419  * \brief Sets the access mode for the tasks that will be executed on a workstation
 420  *
 421  * By default, a workstation model is shared, i.e. several tasks
 422  * can be executed at the same time on a workstation. The CPU power of
 423  * the workstation is shared between the running tasks on the workstation.
 424  * In sequential mode, only one task can use the workstation, and the other
 425  * tasks wait in a FIFO.
 426  *
 427  * \param workstation a workstation
 428  * \param access_mode the access mode you want to set to this workstation:
 429  * SD_WORKSTATION_SHARED_ACCESS or SD_WORKSTATION_SEQUENTIAL_ACCESS
 430  *
 431  * \see SD_workstation_get_access_mode(), e_SD_workstation_access_mode_t
 432  */
 433 void SD_workstation_set_access_mode(SD_workstation_t workstation,
 434                                     e_SD_workstation_access_mode_t
 435                                     access_mode)
 436 {
 437   if (access_mode == workstation->access_mode) {
 438     return;                     // nothing is changed
 439   }
 440
 441   workstation->access_mode = access_mode;
 442
 443   if (access_mode == SD_WORKSTATION_SHARED_ACCESS) {
 444     xbt_fifo_free(workstation->task_fifo);
 445     workstation->task_fifo = NULL;
 446   } else {
 447     workstation->task_fifo = xbt_fifo_new();
 448   }
 449 }
 450
 451 /* Returns whether a task can start now on a workstation.
 452                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               *//*
 453                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    int __SD_workstation_can_start(SD_workstation_t workstation, SD_task_t task) {
 454                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    SD_CHECK_INIT_DONE();
 455                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    xbt_assert(workstation != NULL && task != NULL, "Invalid parameter");
 456
 457                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    return !__SD_workstation_is_busy(workstation) &&
 458                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    (xbt_fifo_size(workstation->task_fifo) == 0) || xbt_fifo_get_first_item(workstation->task_fifo) == task);
 459                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    }
 460                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  */
 461
 462 /* Returns whether a workstation is busy. A workstation is busy is it is
 463  * in sequential mode and a task is running on it or the fifo is not empty.
 464  */
 465 int __SD_workstation_is_busy(SD_workstation_t workstation)
 466 {
 467   XBT_DEBUG
 468       ("Workstation '%s' access mode: '%s', current task: %s, fifo size: %d",
 469        SD_workstation_get_name(workstation),
 470        (workstation->access_mode ==
 471         SD_WORKSTATION_SHARED_ACCESS) ? "SHARED" : "FIFO",
 472        (workstation->current_task ?
 473         SD_task_get_name(workstation->current_task)
 474         : "none"),
 475        (workstation->task_fifo ? xbt_fifo_size(workstation->task_fifo) :
 476         0));
 477
 478   return workstation->access_mode == SD_WORKSTATION_SEQUENTIAL_ACCESS &&
 479       (workstation->current_task != NULL
 480        || xbt_fifo_size(workstation->task_fifo) > 0);
 481 }
 482
 483 /* Destroys a workstation.
 484  */
 485 void __SD_workstation_destroy(void *workstation)
 486 {
 487
 488   SD_workstation_t w;
 489
 490   /* workstation->surf_workstation is freed by surf_exit and workstation->data is freed by the user */
 491
 492   w = (SD_workstation_t) workstation;
 493
 494   if (w->access_mode == SD_WORKSTATION_SEQUENTIAL_ACCESS) {
 495     xbt_fifo_free(w->task_fifo);
 496   }
 497   xbt_free(w);
 498 }
 499
 500 /**
 501  * \brief Returns the kind of the task currently running on a workstation
 502  * Only call this with sequential access mode set
 503  * \param workstation a workstation */
 504 SD_task_t SD_workstation_get_current_task(SD_workstation_t workstation)
 505 {
 506   xbt_assert(workstation->access_mode == SD_WORKSTATION_SEQUENTIAL_ACCESS,
 507               "Access mode must be set to SD_WORKSTATION_SEQUENTIAL_ACCESS"
 508               " to use this function");
 509
 510   return (workstation->current_task);
 511 }