src/simdag/sd_workstation.c

   1 /* Copyright (c) 2006, 2007, 2008, 2009, 2010. 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
  13 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(sd_workstation, sd,
  14                                 "Logging specific to SimDag (workstation)");
  15
  16 /* Creates a workstation and registers it in SD.
  17  */
  18 SD_workstation_t __SD_workstation_create(void *surf_workstation, void *data)
  19 {
  20
  21   SD_workstation_t workstation;
  22   const char *name;
  23   SD_CHECK_INIT_DONE();
  24   xbt_assert0(surf_workstation != NULL, "surf_workstation is NULL !");
  25
  26   workstation = xbt_new(s_SD_workstation_t, 1);
  27   workstation->surf_workstation = surf_workstation;
  28   workstation->data = data;     /* user data */
  29   workstation->access_mode = SD_WORKSTATION_SHARED_ACCESS;      /* default mode is shared */
  30   workstation->task_fifo = NULL;
  31   workstation->current_task = NULL;
  32
  33   name = SD_workstation_get_name(workstation);
  34   xbt_dict_set(sd_global->workstations, name, workstation, __SD_workstation_destroy);   /* add the workstation to the dictionary */
  35   sd_global->workstation_count++;
  36
  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   SD_CHECK_INIT_DONE();
  51
  52   xbt_assert0(name != NULL, "Invalid parameter");
  53
  54   return xbt_dict_get_or_null(sd_global->workstations, name);
  55 }
  56
  57 /**
  58  * \brief Returns the workstation list
  59  *
  60  * Use SD_workstation_get_number() to know the array size.
  61  *
  62  * \return an array of \ref SD_workstation_t containing all workstations
  63  * \see SD_workstation_get_number()
  64  */
  65 const SD_workstation_t *SD_workstation_get_list(void)
  66 {
  67
  68   xbt_dict_cursor_t cursor;
  69   char *key;
  70   void *data;
  71   int i;
  72
  73   SD_CHECK_INIT_DONE();
  74   xbt_assert0(SD_workstation_get_number() > 0, "There is no workstation!");
  75
  76   if (sd_global->workstation_list == NULL) {    /* this is the first time the function is called */
  77     sd_global->workstation_list =
  78       xbt_new(SD_workstation_t, sd_global->workstation_count);
  79
  80     i = 0;
  81     xbt_dict_foreach(sd_global->workstations, cursor, key, data) {
  82       sd_global->workstation_list[i++] = (SD_workstation_t) data;
  83     }
  84   }
  85   return sd_global->workstation_list;
  86 }
  87
  88 /**
  89  * \brief Returns the number of workstations
  90  *
  91  * \return the number of existing workstations
  92  * \see SD_workstation_get_list()
  93  */
  94 int SD_workstation_get_number(void)
  95 {
  96   SD_CHECK_INIT_DONE();
  97   return sd_global->workstation_count;
  98 }
  99
 100 /**
 101  * \brief Returns the user data of a workstation
 102  *
 103  * \param workstation a workstation
 104  * \return the user data associated with this workstation (can be \c NULL)
 105  * \see SD_workstation_set_data()
 106  */
 107 void *SD_workstation_get_data(SD_workstation_t workstation)
 108 {
 109   SD_CHECK_INIT_DONE();
 110   xbt_assert0(workstation != NULL, "Invalid parameter");
 111   return workstation->data;
 112 }
 113
 114 /**
 115  * \brief Sets the user data of a workstation
 116  *
 117  * The new data can be \c NULL. The old data should have been freed first
 118  * if it was not \c NULL.
 119  *
 120  * \param workstation a workstation
 121  * \param data the new data you want to associate with this workstation
 122  * \see SD_workstation_get_data()
 123  */
 124 void SD_workstation_set_data(SD_workstation_t workstation, void *data)
 125 {
 126   SD_CHECK_INIT_DONE();
 127   xbt_assert0(workstation != NULL, "Invalid parameter");
 128   workstation->data = data;
 129 }
 130
 131 /**
 132  * \brief Returns the name of a workstation
 133  *
 134  * \param workstation a workstation
 135  * \return the name of this workstation (cannot be \c NULL)
 136  */
 137 const char *SD_workstation_get_name(SD_workstation_t workstation)
 138 {
 139   SD_CHECK_INIT_DONE();
 140   xbt_assert0(workstation != NULL, "Invalid parameter");
 141   return surf_resource_name(workstation->surf_workstation);
 142 }
 143
 144 /**
 145  * \brief Returns the value of a given workstation property
 146  *
 147  * \param ws a workstation
 148  * \param name a property name
 149  * \return value of a property (or NULL if property not set)
 150  */
 151 const char *SD_workstation_get_property_value(SD_workstation_t ws,
 152                                               const char *name)
 153 {
 154   return xbt_dict_get_or_null(SD_workstation_get_properties(ws), name);
 155 }
 156
 157
 158 /**
 159  * \brief Returns a #xbt_dict_t consisting of the list of properties assigned to this workstation
 160  *
 161  * \param workstation a workstation
 162  * \return the dictionary containing the properties associated with the workstation
 163  */
 164 xbt_dict_t SD_workstation_get_properties(SD_workstation_t workstation)
 165 {
 166   SD_CHECK_INIT_DONE();
 167   xbt_assert0((workstation != NULL), "Invalid parameters");
 168
 169   return surf_workstation_model->extension.workstation.get_properties(workstation->surf_workstation);
 170
 171 }
 172
 173
 174 /**
 175  * \brief Returns the route between two workstations
 176  *
 177  * Use SD_route_get_size() to know the array size.
 178  *
 179  * \param src a workstation
 180  * \param dst another workstation
 181  * \return a new array of \ref SD_link_t representating the route between these two workstations
 182  * \see SD_route_get_size(), SD_link_t
 183  */
 184 const SD_link_t *SD_route_get_list(SD_workstation_t src, SD_workstation_t dst)
 185 {
 186   void *surf_src;
 187   void *surf_dst;
 188   xbt_dynar_t surf_route;
 189   const char *link_name;
 190   void *surf_link;
 191   unsigned int cpt;
 192
 193   SD_CHECK_INIT_DONE();
 194
 195   if (sd_global->recyclable_route == NULL) {
 196     /* first run */
 197     sd_global->recyclable_route = xbt_new(SD_link_t, SD_link_get_number());
 198   }
 199
 200   surf_src = src->surf_workstation;
 201   surf_dst = dst->surf_workstation;
 202   surf_route = surf_workstation_model->extension.workstation.get_route(surf_src,surf_dst);
 203
 204   xbt_dynar_foreach(surf_route, cpt, surf_link) {
 205     link_name = surf_resource_name(surf_link);
 206     sd_global->recyclable_route[cpt] =
 207       xbt_dict_get(sd_global->links, link_name);
 208   }
 209   return sd_global->recyclable_route;
 210 }
 211
 212 /**
 213  * \brief Returns the number of links on the route between two workstations
 214  *
 215  * \param src a workstation
 216  * \param dst another workstation
 217  * \return the number of links on the route between these two workstations
 218  * \see SD_route_get_list()
 219  */
 220 int SD_route_get_size(SD_workstation_t src, SD_workstation_t dst)
 221 {
 222   SD_CHECK_INIT_DONE();
 223   return xbt_dynar_length(surf_workstation_model->extension.workstation.get_route(
 224         src->surf_workstation,dst->surf_workstation));
 225 }
 226
 227 /**
 228  * \brief Returns the total power of a workstation
 229  *
 230  * \param workstation a workstation
 231  * \return the total power of this workstation
 232  * \see SD_workstation_get_available_power()
 233  */
 234 double SD_workstation_get_power(SD_workstation_t workstation)
 235 {
 236   SD_CHECK_INIT_DONE();
 237   xbt_assert0(workstation != NULL, "Invalid parameter");
 238   return surf_workstation_model->extension.workstation.
 239     get_speed(workstation->surf_workstation, 1.0);
 240 }
 241
 242 /**
 243  * \brief Returns the proportion of available power in a workstation
 244  *
 245  * \param workstation a workstation
 246  * \return the proportion of power currently available in this workstation (normally a number between 0 and 1)
 247  * \see SD_workstation_get_power()
 248  */
 249 double SD_workstation_get_available_power(SD_workstation_t workstation)
 250 {
 251   SD_CHECK_INIT_DONE();
 252   xbt_assert0(workstation != NULL, "Invalid parameter");
 253   return surf_workstation_model->extension.
 254     workstation.get_available_speed(workstation->surf_workstation);
 255 }
 256
 257 /**
 258  * \brief Returns an approximative estimated time for the given computation amount on a workstation
 259  *
 260  * \param workstation a workstation
 261  * \param computation_amount the computation amount you want to evaluate (in flops)
 262  * \return an approximative astimated computation time for the given computation amount on this workstation (in seconds)
 263  */
 264 double SD_workstation_get_computation_time(SD_workstation_t workstation,
 265                                            double computation_amount)
 266 {
 267   SD_CHECK_INIT_DONE();
 268   xbt_assert0(workstation != NULL, "Invalid parameter");
 269   xbt_assert0(computation_amount >= 0,
 270               "computation_amount must be greater than or equal to zero");
 271   return computation_amount / SD_workstation_get_power(workstation);
 272 }
 273
 274 /**
 275  * \brief Returns the latency of the route between two workstations, i.e. the sum of all link latencies
 276  * between the workstations.
 277  *
 278  * \param src the first workstation
 279  * \param dst the second workstation
 280  * \return the latency of the route between the two workstations (in seconds)
 281  * \see SD_route_get_current_bandwidth()
 282  */
 283 double SD_route_get_current_latency(SD_workstation_t src,
 284                                     SD_workstation_t dst)
 285 {
 286
 287   const SD_link_t *links;
 288   int nb_links;
 289   double latency;
 290   int i;
 291
 292   SD_CHECK_INIT_DONE();
 293   xbt_assert0(src != NULL && dst != NULL, "Invalid parameter");
 294   links = SD_route_get_list(src, dst);
 295   nb_links = SD_route_get_size(src, dst);
 296   latency = 0.0;
 297
 298   for (i = 0; i < nb_links; i++) {
 299     latency += SD_link_get_current_latency(links[i]);
 300   }
 301
 302   return latency;
 303 }
 304
 305 /**
 306  * \brief Returns the bandwidth of the route between two workstations, i.e. the minimum link bandwidth of all
 307  * between the workstations.
 308  *
 309  * \param src the first workstation
 310  * \param dst the second workstation
 311  * \return the bandwidth of the route between the two workstations (in bytes/second)
 312  * \see SD_route_get_current_latency()
 313  */
 314 double SD_route_get_current_bandwidth(SD_workstation_t src,
 315                                       SD_workstation_t dst)
 316 {
 317
 318   const SD_link_t *links;
 319   int nb_links;
 320   double bandwidth;
 321   double min_bandwidth;
 322   int i;
 323
 324   SD_CHECK_INIT_DONE();
 325   xbt_assert0(src != NULL && dst != NULL, "Invalid parameter");
 326
 327   links = SD_route_get_list(src, dst);
 328   nb_links = SD_route_get_size(src, dst);
 329   bandwidth = min_bandwidth = -1.0;
 330
 331
 332   for (i = 0; i < nb_links; i++) {
 333     bandwidth = SD_link_get_current_bandwidth(links[i]);
 334     if (bandwidth < min_bandwidth || min_bandwidth == -1.0)
 335       min_bandwidth = bandwidth;
 336   }
 337
 338   return min_bandwidth;
 339 }
 340
 341 /**
 342  * \brief Returns an approximative estimated time for the given
 343  * communication amount between two workstations
 344  *
 345  * \param src the first workstation
 346  * \param dst the second workstation
 347  * \param communication_amount the communication amount you want to evaluate (in bytes)
 348  * \return an approximative astimated computation time for the given communication amount
 349  * between the workstations (in seconds)
 350  */
 351 double SD_route_get_communication_time(SD_workstation_t src,
 352                                        SD_workstation_t dst,
 353                                        double communication_amount)
 354 {
 355
 356
 357   /* total time = latency + transmission time of the slowest link
 358      transmission time of a link = communication amount / link bandwidth */
 359
 360   const SD_link_t *links;
 361   int nb_links;
 362   double bandwidth, min_bandwidth;
 363   double latency;
 364   int i;
 365
 366   SD_CHECK_INIT_DONE();
 367   xbt_assert0(src != NULL && dst != NULL, "Invalid parameter");
 368   xbt_assert0(communication_amount >= 0,
 369               "communication_amount must be greater than or equal to zero");
 370
 371
 372
 373   if (communication_amount == 0.0)
 374     return 0.0;
 375
 376   links = SD_route_get_list(src, dst);
 377   nb_links = SD_route_get_size(src, dst);
 378   min_bandwidth = -1.0;
 379   latency = 0;
 380
 381   for (i = 0; i < nb_links; i++) {
 382     latency += SD_link_get_current_latency(links[i]);
 383     bandwidth = SD_link_get_current_bandwidth(links[i]);
 384     if (bandwidth < min_bandwidth || min_bandwidth == -1.0)
 385       min_bandwidth = bandwidth;
 386   }
 387
 388   return latency + (communication_amount / min_bandwidth);
 389 }
 390
 391 /**
 392  * \brief Returns the access mode of this workstation.
 393  *
 394  * \param workstation a workstation
 395  * \return the access mode for the tasks running on this workstation:
 396  * SD_WORKSTATION_SHARED_ACCESS or SD_WORKSTATION_SEQUENTIAL_ACCESS
 397  *
 398  * \see SD_workstation_set_access_mode(), e_SD_workstation_access_mode_t
 399  */
 400 e_SD_workstation_access_mode_t SD_workstation_get_access_mode(SD_workstation_t
 401                                                               workstation)
 402 {
 403   SD_CHECK_INIT_DONE();
 404   xbt_assert0(workstation != NULL, "Invalid parameter");
 405   return workstation->access_mode;
 406 }
 407
 408 /**
 409  * \brief Sets the access mode for the tasks that will be executed on a workstation
 410  *
 411  * By default, a workstation model is shared, i.e. several tasks
 412  * can be executed at the same time on a workstation. The CPU power of
 413  * the workstation is shared between the running tasks on the workstation.
 414  * In sequential mode, only one task can use the workstation, and the other
 415  * tasks wait in a FIFO.
 416  *
 417  * \param workstation a workstation
 418  * \param access_mode the access mode you want to set to this workstation:
 419  * SD_WORKSTATION_SHARED_ACCESS or SD_WORKSTATION_SEQUENTIAL_ACCESS
 420  *
 421  * \see SD_workstation_get_access_mode(), e_SD_workstation_access_mode_t
 422  */
 423 void SD_workstation_set_access_mode(SD_workstation_t workstation,
 424                                     e_SD_workstation_access_mode_t
 425                                     access_mode)
 426 {
 427   SD_CHECK_INIT_DONE();
 428   xbt_assert0(workstation != NULL, "Invalid parameter");
 429
 430   if (access_mode == workstation->access_mode) {
 431     return;                     // nothing is changed
 432   }
 433
 434   workstation->access_mode = access_mode;
 435
 436   if (access_mode == SD_WORKSTATION_SHARED_ACCESS) {
 437     xbt_fifo_free(workstation->task_fifo);
 438     workstation->task_fifo = NULL;
 439   } else {
 440     workstation->task_fifo = xbt_fifo_new();
 441   }
 442 }
 443
 444 /* Returns whether a task can start now on a workstation.
 445                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               *//*
 446                                                                                                                                                                                                                                                                                                                                                                                                    int __SD_workstation_can_start(SD_workstation_t workstation, SD_task_t task) {
 447                                                                                                                                                                                                                                                                                                                                                                                                    SD_CHECK_INIT_DONE();
 448                                                                                                                                                                                                                                                                                                                                                                                                    xbt_assert0(workstation != NULL && task != NULL, "Invalid parameter");
 449
 450                                                                                                                                                                                                                                                                                                                                                                                                    return !__SD_workstation_is_busy(workstation) &&
 451                                                                                                                                                                                                                                                                                                                                                                                                    (xbt_fifo_size(workstation->task_fifo) == 0) || xbt_fifo_get_first_item(workstation->task_fifo) == task);
 452                                                                                                                                                                                                                                                                                                                                                                                                    }
 453                                                                                                                                                                                                                                                                                                                                                                                                  */
 454
 455 /* Returns whether a workstation is busy. A workstation is busy is it is
 456  * in sequential mode and a task is running on it or the fifo is not empty.
 457  */
 458 int __SD_workstation_is_busy(SD_workstation_t workstation)
 459 {
 460   SD_CHECK_INIT_DONE();
 461   xbt_assert0(workstation != NULL, "Invalid parameter");
 462
 463   DEBUG4
 464     ("Workstation '%s' access mode: '%s', current task: %s, fifo size: %d",
 465      SD_workstation_get_name(workstation),
 466      (workstation->access_mode ==
 467       SD_WORKSTATION_SHARED_ACCESS) ? "SHARED" : "FIFO",
 468      (workstation->current_task ? SD_task_get_name(workstation->current_task)
 469       : "none"),
 470      (workstation->task_fifo ? xbt_fifo_size(workstation->task_fifo) : 0));
 471
 472   return workstation->access_mode == SD_WORKSTATION_SEQUENTIAL_ACCESS &&
 473     (workstation->current_task != NULL
 474      || xbt_fifo_size(workstation->task_fifo) > 0);
 475 }
 476
 477 /* Destroys a workstation.
 478  */
 479 void __SD_workstation_destroy(void *workstation)
 480 {
 481
 482   SD_workstation_t w;
 483
 484   SD_CHECK_INIT_DONE();
 485   xbt_assert0(workstation != NULL, "Invalid parameter");
 486   /* workstation->surf_workstation is freed by surf_exit and workstation->data is freed by the user */
 487
 488   w = (SD_workstation_t) workstation;
 489
 490   if (w->access_mode == SD_WORKSTATION_SEQUENTIAL_ACCESS) {
 491     xbt_fifo_free(w->task_fifo);
 492   }
 493   xbt_free(w);
 494 }
 495
 496 /**
 497  * \brief Returns the kind of the task currently running on a workstation
 498  * Only call this with sequential access mode set
 499  * \param workstation a workstation */
 500 SD_task_t SD_workstation_get_current_task(SD_workstation_t workstation)
 501 {
 502   SD_CHECK_INIT_DONE();
 503   xbt_assert0(workstation != NULL, "Invalid parameter");
 504   xbt_assert0(workstation->access_mode == SD_WORKSTATION_SEQUENTIAL_ACCESS,
 505               "Access mode must be set to SD_WORKSTATION_SEQUENTIAL_ACCESS"
 506               " to use this function");
 507
 508   return (workstation->current_task);
 509 }