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 "frescan_bwres_mode_change.h"
  69 #include "frescan_data.h"
  70 #include "frescan_servers.h"
  71 #include "frescan_bwres_messages.h"
  72 #include <misc/linux_list.h>
  73
  74
  75 int frescan_bwres_budget_change(frescan_request_data_t *req_data,
  76                                 frescan_node_t node,
  77                                 frescan_sa_mode_change_type_t mode_change_type);
  78
  79 /**
  80  * frescan_bwres_mode_change_protocol() - performs the mode change
  81  *
  82  * Follow the mode change protocol described in the paper.
  83  *
  84  */
  85
  86 int frescan_bwres_mode_change_protocol(frescan_request_data_t *req_data)
  87 {
  88         int ret, i;
  89         frescan_node_t node;
  90         frescan_sa_vres_t *vres;
  91         frsh_sa_vres_data_t *sa_vres_data;
  92         frsh_sa_time_t max_period_in_budget_dec;
  93         frsh_sa_time_t max_period_in_budget_inc;
  94         struct timespec start_timestamp, next_activation;
  95
  96         for(node=0; node<FRESCAN_MX_NODES; node++) {
  97                 INIT_LIST_HEAD(&the_networks[req_data->net].
  98                                 mode_change_budget_inc_list_head[node]);
  99
 100                 INIT_LIST_HEAD(&the_networks[req_data->net].
 101                                 mode_change_budget_dec_list_head[node]);
 102         }
 103
 104         max_period_in_budget_dec = (frsh_sa_time_t)0;
 105         max_period_in_budget_inc = (frsh_sa_time_t)0;
 106
 107         list_for_each_entry
 108                         (vres,
 109                          &the_networks[req_data->net].scenario.vres_head.list,
 110                          list)
 111         {
 112                 sa_vres_data = &the_networks[req_data->net].
 113                                 scenario.fsa_scenario.sa_vres_alloc
 114                                                 [vres->fsa_vres_global_id];
 115
 116                 vres->mode_change_type = 0;
 117
 118                 if (sa_vres_data->c > vres->old_c) {
 119                         vres->mode_change_type |= FRESCAN_SA_BUDGET_INC;
 120
 121                         if (sa_vres_data->t > max_period_in_budget_inc) {
 122                                 max_period_in_budget_inc = sa_vres_data->t;
 123                         }
 124
 125                         list_add_tail
 126                             (&(vres->mode_change_list),
 127                              &(the_networks[req_data->net].
 128                                mode_change_budget_inc_list_head[vres->node]));
 129                 } else {
 130                         vres->mode_change_type |= FRESCAN_SA_BUDGET_DEC;
 131
 132                         if (sa_vres_data->t > max_period_in_budget_dec) {
 133                                 max_period_in_budget_dec = sa_vres_data->t;
 134                         }
 135
 136                         list_add_tail
 137                             (&(vres->mode_change_list),
 138                              &(the_networks[req_data->net].
 139                                mode_change_budget_dec_list_head[vres->node]));
 140                 }
 141
 142                 if (sa_vres_data->t > vres->old_t) {
 143                         vres->mode_change_type |= FRESCAN_SA_PERIOD_INC;
 144                 } else {
 145                         vres->mode_change_type |= FRESCAN_SA_PERIOD_DEC;
 146                 }
 147
 148                 if (sa_vres_data->p > vres->old_p) {
 149                         vres->mode_change_type |= FRESCAN_SA_PRIO_INC;
 150                 } else {
 151                         vres->mode_change_type |= FRESCAN_SA_PRIO_DEC;
 152                 }
 153
 154                 vres->old_c = sa_vres_data->c;
 155                 vres->old_t = sa_vres_data->t;
 156                 vres->old_p = sa_vres_data->p;
 157         }
 158
 159         // 1.- mode change for B- members
 160         for(i=(FRESCAN_MX_NODES-1); i>=0; i--) {
 161                 ret = frescan_bwres_budget_change(req_data,
 162                                                   (frescan_node_t)i,
 163                                                   FRESCAN_SA_BUDGET_DEC);
 164                 if (ret != 0) return -1;
 165         }
 166
 167         // 2.- wait the time needed to keep schedulability
 168         ret = clock_gettime(CLOCK_MONOTONIC,
 169                             &start_timestamp);
 170         if (ret != 0) return -1;
 171
 172         add_timespec(next_activation,
 173                      frsh_rel_time_to_timespec(frsh_sa_time_to_rel_time
 174                                                 (max_period_in_budget_inc)),
 175                      frsh_rel_time_to_timespec(frsh_sa_time_to_rel_time
 176                                                 (max_period_in_budget_dec)));
 177
 178         incr_timespec(next_activation, start_timestamp);
 179
 180         ret = clock_nanosleep(CLOCK_MONOTONIC,
 181                               TIMER_ABSTIME,
 182                               &next_activation,
 183                               NULL);
 184         if (ret != 0) return -1;
 185
 186         // 3-. mode change for B+ members
 187         for(i=(FRESCAN_MX_NODES-1); i>=0; i--) {
 188                 ret = frescan_bwres_budget_change(req_data,
 189                                                   (frescan_node_t)i,
 190                                                   FRESCAN_SA_BUDGET_INC);
 191                 if (ret != 0) return -1;
 192         }
 193
 194         return 0;
 195 }
 196
 197 int frescan_bwres_budget_change
 198                 (frescan_request_data_t *req_data,
 199                  frescan_node_t node,
 200                  frescan_sa_mode_change_type_t mode_change_type)
 201 {
 202         int ret;
 203         frescan_server_params_t server_params;
 204         frescan_sa_vres_t *vres;
 205         frescan_request_data_t tmp_req_data;
 206         struct timespec start_timestamp, next_activation;
 207         struct list_head *the_mode_change_list;
 208         frescan_node_t me = the_networks[req_data->net].local_node;
 209
 210         if (mode_change_type == FRESCAN_SA_BUDGET_INC) {
 211                 the_mode_change_list = &the_networks[req_data->net].
 212                                 mode_change_budget_inc_list_head[node];
 213         } else {
 214                 the_mode_change_list = &the_networks[req_data->net].
 215                                 mode_change_budget_dec_list_head[node];
 216         }
 217
 218         list_for_each_entry(vres, the_mode_change_list, mode_change_list)
 219         {
 220                 server_params.budget = frsh_rel_time_to_usec(
 221                                 frsh_sa_time_to_rel_time(vres->old_c)) /
 222                                 FRESCAN_FRAME_TX_TIME_US;
 223                 server_params.period = frsh_sa_time_to_rel_time(vres->old_t);
 224                 server_params.prio   = vres->old_p;
 225
 226                 if (node == me) {
 227                         if (mode_change_type == FRESCAN_SA_BUDGET_INC) {
 228                                 ret = frescan_servers_update(req_data->net,
 229                                                              &server_params,
 230                                                              vres->ss);
 231                                 if (ret != 0) return ret;
 232                         } else {
 233                                 ret = frescan_servers_set_perceived
 234                                      (req_data->net, &server_params, vres->ss);
 235                                 if (ret != 0) return ret;
 236                         }
 237                 } else {
 238                         if ((node == req_data->request_node) &&
 239                             (vres->ss == req_data->ss)) {
 240                                 // External: send reply to reneg
 241                                 req_data->type = FRESCAN_REP_NEG;
 242                                 req_data->final_values = server_params;
 243
 244                                 ret = frescan_messages_send_request(req_data);
 245                                 if (ret != 0) return -1;
 246                         } else {
 247                                 // External: send SC change update
 248                                 tmp_req_data.net  = req_data->net;
 249                                 tmp_req_data.request_node = node;
 250
 251                                 if (mode_change_type == FRESCAN_SA_BUDGET_INC) {
 252                                         tmp_req_data.type =
 253                                                         FRESCAN_REP_INC_BUDGET;
 254                                 } else {
 255                                         tmp_req_data.type =
 256                                                         FRESCAN_REP_DEC_BUDGET;
 257                                 }
 258
 259                                 ret = frescan_messages_send_request
 260                                                                (&tmp_req_data);
 261                                 if (ret != 0) return -1;
 262                         }
 263                 }
 264         }
 265
 266         if (mode_change_type == FRESCAN_SA_BUDGET_INC) return 0;
 267
 268         if (node == me) {
 269                 ret = clock_gettime(CLOCK_MONOTONIC, &start_timestamp);
 270                 if (ret != 0) return -1;
 271
 272                 list_for_each_entry
 273                         (vres, the_mode_change_list, mode_change_list)
 274                 {
 275                         add_timespec(next_activation,
 276                                      start_timestamp,
 277                                      frsh_rel_time_to_timespec
 278                                                 (frsh_sa_time_to_rel_time
 279                                                         (vres->old_t)));
 280
 281                         ret = clock_nanosleep(CLOCK_MONOTONIC,
 282                                               TIMER_ABSTIME,
 283                                               &next_activation,
 284                                               NULL);
 285                         if (ret != 0) return -1;
 286
 287                         ret = frescan_servers_commit_perceived(req_data->net,
 288                                                                vres->ss);
 289                         if (ret != 0) return ret;
 290                 }
 291         }
 292
 293         return 0;
 294 }