src_frescan/frescan_bwres_mode_change.c

   1 /*!
   2  * @file frescan_bwres_analysis.h
   3  *
   4  * @brief FRESCAN bandwith reservation layer: mode change protocol
   5  *
   6  * @version 0.02
   7  *
   8  * @date 19-Jul-2008
   9  *
  10  * @author Daniel Sangorrin <daniel.sangorrin@unican.es>
  11  *
  12  * @comments
  13  *
  14  * This module contains the mode change protocol
  15  *
  16  * @license
  17  *
  18  * -----------------------------------------------------------------------
  19  *  Copyright (C) 2006 - 2008 FRESCOR consortium partners:
  20  *
  21  *    Universidad de Cantabria,              SPAIN
  22  *    University of York,                    UK
  23  *    Scuola Superiore Sant'Anna,            ITALY
  24  *    Kaiserslautern University,             GERMANY
  25  *    Univ. Politécnica  Valencia,           SPAIN
  26  *    Czech Technical University in Prague,  CZECH REPUBLIC
  27  *    ENEA                                   SWEDEN
  28  *    Thales Communication S.A.              FRANCE
  29  *    Visual Tools S.A.                      SPAIN
  30  *    Rapita Systems Ltd                     UK
  31  *    Evidence                               ITALY
  32  *
  33  *    See http://www.frescor.org for a link to partners' websites
  34  *
  35  *           FRESCOR project (FP6/2005/IST/5-034026) is funded
  36  *        in part by the European Union Sixth Framework Programme
  37  *        The European Union is not liable of any use that may be
  38  *        made of this code.
  39  *
  40  *  This file is part of FRESCAN
  41  *
  42  *  FRESCAN is free software; you can  redistribute it and/or  modify
  43  *  it under the terms of  the GNU General Public License as published by
  44  *  the Free Software Foundation;  either  version 2, or (at  your option)
  45  *  any later version.
  46  *
  47  *  FRESCAN  is distributed  in  the hope  that  it  will  be useful,  but
  48  *  WITHOUT  ANY  WARRANTY;     without  even the   implied   warranty  of
  49  *  MERCHANTABILITY  or  FITNESS FOR  A  PARTICULAR PURPOSE. See  the  GNU
  50  *  General Public License for more details.
  51  *
  52  *  You should have  received a  copy of  the  GNU  General Public License
  53  *  distributed  with  FRESCAN;  see file COPYING.   If not,  write to the
  54  *  Free Software  Foundation,  59 Temple Place  -  Suite 330,  Boston, MA
  55  *  02111-1307, USA.
  56  *
  57  * As a special exception, including FRESCAN header files in a file,
  58  * instantiating FRESCAN generics or templates, or linking other files
  59  * with FRESCAN objects to produce an executable application, does not
  60  * by itself cause the resulting executable application to be covered
  61  * by the GNU General Public License. This exception does not
  62  * however invalidate any other reasons why the executable file might be
  63  * covered by the GNU Public License.
  64  * -----------------------------------------------------------------------
  65  *
  66  */
  67
  68 #include <misc/linux_list.h>
  69 #include <stdbool.h>
  70
  71 #include "frescan_data.h"
  72 #include "frescan_servers.h"
  73 #include "frescan_bwres_messages.h"
  74 #include "frescan_bwres_mode_change.h"
  75 #include "frescan_debug.h"
  76
  77 int frescan_bwres_budget_change(frescan_request_data_t *req_data,
  78                                 frescan_node_t node,
  79                                 frescan_sa_mode_change_type_t mode_change_type);
  80
  81 /**
  82  * frescan_bwres_mode_change_protocol() - performs the mode change
  83  *
  84  * Follow the mode change protocol described in the paper.
  85  *
  86  */
  87
  88 int frescan_bwres_mode_change_protocol(frescan_request_data_t *req_data)
  89 {
  90         int ret, i;
  91         frescan_node_t node;
  92         frescan_sa_vres_t *vres;
  93         frsh_sa_vres_data_t *sa_vres_data;
  94         frsh_sa_time_t max_period_in_budget_dec;
  95         frsh_sa_time_t max_period_in_budget_inc;
  96         struct timespec start_timestamp, next_activation;
  97
  98         DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG, "starting mode change\n");
  99
 100         for(node=0; node<FRESCAN_MX_NODES; node++) {
 101                 INIT_LIST_HEAD(&the_networks[req_data->net].
 102                                 mode_change_budget_inc_list_head[node]);
 103
 104                 INIT_LIST_HEAD(&the_networks[req_data->net].
 105                                 mode_change_budget_dec_list_head[node]);
 106         }
 107
 108         max_period_in_budget_dec = (frsh_sa_time_t)0;
 109         max_period_in_budget_inc = (frsh_sa_time_t)0;
 110
 111         list_for_each_entry
 112                         (vres,
 113                          &the_networks[req_data->net].scenario.vres_head.list,
 114                          list)
 115         {
 116                 sa_vres_data = &the_networks[req_data->net].
 117                                 scenario.fsa_scenario.sa_vres_alloc
 118                                                 [vres->fsa_vres_global_id];
 119
 120                 vres->mode_change_type = 0;
 121
 122                 if (sa_vres_data->c > vres->old_c) {
 123                         vres->mode_change_type |= FRESCAN_SA_BUDGET_INC;
 124
 125                         if (sa_vres_data->t > max_period_in_budget_inc) {
 126                                 max_period_in_budget_inc = sa_vres_data->t;
 127                         }
 128
 129                         list_add_tail
 130                             (&(vres->mode_change_list),
 131                              &(the_networks[req_data->net].
 132                                mode_change_budget_inc_list_head[vres->node]));
 133                 } else if (sa_vres_data->c < vres->old_c) {
 134                         vres->mode_change_type |= FRESCAN_SA_BUDGET_DEC;
 135
 136                         if (sa_vres_data->t > max_period_in_budget_dec) {
 137                                 max_period_in_budget_dec = sa_vres_data->t;
 138                         }
 139
 140                         list_add_tail
 141                             (&(vres->mode_change_list),
 142                              &(the_networks[req_data->net].
 143                                mode_change_budget_dec_list_head[vres->node]));
 144                 }
 145
 146                 if (sa_vres_data->t > vres->old_t) {
 147                         vres->mode_change_type |= FRESCAN_SA_PERIOD_INC;
 148                 } else if (sa_vres_data->t < vres->old_t) {
 149                         vres->mode_change_type |= FRESCAN_SA_PERIOD_DEC;
 150                 }
 151
 152                 if (sa_vres_data->p > vres->old_p) {
 153                         vres->mode_change_type |= FRESCAN_SA_PRIO_INC;
 154                 } else if (sa_vres_data->p < vres->old_p) {
 155                         vres->mode_change_type |= FRESCAN_SA_PRIO_DEC;
 156                 }
 157
 158                 vres->old_c = sa_vres_data->c;
 159                 vres->old_t = sa_vres_data->t;
 160                 vres->old_p = sa_vres_data->p;
 161
 162                 DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 163                       "vres: %u type: %X budget_change: %s\n",
 164                       vres->fsa_vres_global_id,
 165                       vres->mode_change_type,
 166                       ((vres->mode_change_type & FRESCAN_SA_BUDGET_INC) ==
 167                        FRESCAN_SA_BUDGET_INC) ? "inc" : "dec");
 168         }
 169
 170         // 1.- mode change for B- members
 171         for(i=(FRESCAN_MX_NODES-1); i>=0; i--) {
 172                 ret = frescan_bwres_budget_change(req_data,
 173                                                   (frescan_node_t)i,
 174                                                   FRESCAN_SA_BUDGET_DEC);
 175                 if (ret != 0) return -1;
 176         }
 177
 178         // 2.- wait the time needed to keep schedulability
 179         ret = clock_gettime(CLOCK_MONOTONIC,
 180                             &start_timestamp);
 181         if (ret != 0) return -1;
 182
 183         add_timespec(next_activation,
 184                      frsh_rel_time_to_timespec(frsh_sa_time_to_rel_time
 185                                                 (max_period_in_budget_inc)),
 186                      frsh_rel_time_to_timespec(frsh_sa_time_to_rel_time
 187                                                 (max_period_in_budget_dec)));
 188
 189         incr_timespec(next_activation, start_timestamp);
 190
 191         ret = clock_nanosleep(CLOCK_MONOTONIC,
 192                               TIMER_ABSTIME,
 193                               &next_activation,
 194                               NULL);
 195         if (ret != 0) return -1;
 196
 197         // 3-. mode change for B+ members
 198         for(i=(FRESCAN_MX_NODES-1); i>=0; i--) {
 199                 ret = frescan_bwres_budget_change(req_data,
 200                                                   (frescan_node_t)i,
 201                                                   FRESCAN_SA_BUDGET_INC);
 202                 if (ret != 0) return -1;
 203         }
 204
 205         return 0;
 206 }
 207
 208 int frescan_bwres_budget_change
 209                 (frescan_request_data_t *req_data,
 210                  frescan_node_t node,
 211                  frescan_sa_mode_change_type_t mode_change_type)
 212 {
 213         int ret;
 214         frescan_server_params_t server_params;
 215         frescan_sa_vres_t *vres;
 216         frescan_request_data_t tmp_req_data;
 217         struct timespec start_timestamp, next_activation;
 218         struct list_head *the_mode_change_list;
 219         frescan_node_t me = the_networks[req_data->net].local_node;
 220         bool is_increase;
 221
 222         is_increase = (mode_change_type & FRESCAN_SA_BUDGET_INC) ==
 223                        FRESCAN_SA_BUDGET_INC;
 224
 225         DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 226               "budget change node: %u (me: %u) type: '%s'\n",
 227                node, me, is_increase ? "inc" : "dec");
 228
 229         if (is_increase) {
 230                 the_mode_change_list = &the_networks[req_data->net].
 231                                 mode_change_budget_inc_list_head[node];
 232         } else {
 233                 the_mode_change_list = &the_networks[req_data->net].
 234                                 mode_change_budget_dec_list_head[node];
 235         }
 236
 237         list_for_each_entry(vres, the_mode_change_list, mode_change_list)
 238         {
 239                 DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 240                       "vres %u\n", vres->fsa_vres_global_id);
 241
 242                 server_params.budget = frsh_rel_time_to_usec(
 243                                 frsh_sa_time_to_rel_time(vres->old_c)) /
 244                                 FRESCAN_FRAME_TX_TIME_US;
 245                 server_params.period = frsh_sa_time_to_rel_time(vres->old_t);
 246                 server_params.prio   = vres->old_p;
 247
 248                 if (node == me) {
 249                         if (is_increase) {
 250                                 DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 251                                       "Local: update server\n");
 252                                 ret = frescan_servers_update(req_data->net,
 253                                                              &server_params,
 254                                                              vres->ss);
 255                                 if (ret != 0) return ret;
 256                         } else {
 257                                 DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 258                                       "Local: set perceived\n");
 259                                 ret = frescan_servers_set_perceived
 260                                      (req_data->net, &server_params, vres->ss);
 261                                 if (ret != 0) return ret;
 262                         }
 263                 } else {
 264                         if ((node == req_data->request_node) &&
 265                             (vres->ss == req_data->ss)) {
 266                                 DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 267                                       "External: send reply to reneg\n");
 268                                 req_data->type = FRESCAN_REP_NEG;
 269                                 req_data->final_values = server_params;
 270
 271                                 ret = frescan_messages_send_request(req_data);
 272                                 if (ret != 0) return -1;
 273                         } else {
 274                                 DEBUG(FRESCAN_MODECHANGE_ENABLE_DEBUG,
 275                                       "External: send SC change update\n");
 276                                 tmp_req_data.net  = req_data->net;
 277                                 tmp_req_data.request_node = node;
 278
 279                                 if (is_increase) {
 280                                         tmp_req_data.type =
 281                                                         FRESCAN_REP_INC_BUDGET;
 282                                 } else {
 283                                         tmp_req_data.type =
 284                                                         FRESCAN_REP_DEC_BUDGET;
 285                                 }
 286
 287                                 ret = frescan_messages_send_request
 288                                                                (&tmp_req_data);
 289                                 if (ret != 0) return -1;
 290                         }
 291                 }
 292         }
 293
 294         if (is_increase) return 0;
 295
 296         if (node == me) {
 297                 ret = clock_gettime(CLOCK_MONOTONIC, &start_timestamp);
 298                 if (ret != 0) return -1;
 299
 300                 list_for_each_entry
 301                         (vres, the_mode_change_list, mode_change_list)
 302                 {
 303                         add_timespec(next_activation,
 304                                      start_timestamp,
 305                                      frsh_rel_time_to_timespec
 306                                                 (frsh_sa_time_to_rel_time
 307                                                         (vres->old_t)));
 308
 309                         ret = clock_nanosleep(CLOCK_MONOTONIC,
 310                                               TIMER_ABSTIME,
 311                                               &next_activation,
 312                                               NULL);
 313                         if (ret != 0) return -1;
 314
 315                         ret = frescan_servers_commit_perceived(req_data->net,
 316                                                                vres->ss);
 317                         if (ret != 0) return ret;
 318                 }
 319         }
 320
 321         return 0;
 322 }