src_frescan/frescan_bwres.c

   1 /*!
   2  * @file frescan_bwres.c
   3  *
   4  * @brief FRESCAN bandwidth reservation layer
   5  *
   6  * This module contains function to negotiate contracts and get the
   7  * corresponding frescan sporadic servers.
   8  *
   9  * @version 0.01
  10  *
  11  * @date 1-Apr-2008
  12  *
  13  * @author Daniel Sangorrin <daniel.sangorrin@unican.es>
  14  *
  15  */
  16
  17 #include "frescan_bwres.h"
  18 #include "frescan_bwres_requests.h"
  19 #include "frescan_bwres_messages.h"
  20 #include "frescan_bwres_threads.h"
  21 #include "frescan_bwres_analysis.h"
  22 #include "frescan_data.h"
  23 #include "frescan_debug.h"
  24 #include "frescan_config.h"
  25 #include "frescan_servers.h"
  26
  27 /**
  28  * frescan_bwres_init()
  29  *
  30  * Init the frescan bandwidth reservation layer
  31  */
  32
  33 int frescan_bwres_init(frescan_network_t net)
  34 {
  35         int ret;
  36         frescan_server_params_t  server_params;  // TODO: improve this...
  37         frescan_sa_init_params_t sa_init_params; // TODO: improve this...
  38
  39         sa_init_params.max_prio = 30;
  40         sa_init_params.min_prio = 1;
  41
  42         ret = frescan_sa_init(&the_networks[net].scenario,
  43                               &sa_init_params);
  44         if (ret != 0) return ret;
  45
  46         server_params.values.budget = 5;
  47         server_params.values.period.tv_sec = 1;
  48         server_params.values.period.tv_nsec = 0;
  49         server_params.prio = FRESCAN_BWRES_NEG_MESSAGES_PRIO;
  50
  51         ret = frescan_servers_create(net, &server_params,
  52                                      &the_networks[net].neg_messages_ss_id);
  53         if (ret != 0) return ret;
  54
  55         // TODO: we have to add this negotiation contracts to the sa table
  56
  57         ret = frescan_bwres_robjs_init(FRESCAN_REPLY_OBJECTS_MX_CEILING);
  58         if (ret != 0) return ret;
  59
  60         ret = frescan_requests_init(FRESCAN_REQUESTS_MX_CEILING);
  61         if (ret != 0) return ret;
  62
  63         ret = frescan_messages_init(net);
  64         if (ret != 0) return ret;
  65
  66         ret = frescan_manager_thread_create(net);
  67         if (ret != 0) return ret;
  68
  69         ret = frescan_acceptor_thread_create(net);
  70         if (ret != 0) return ret;
  71
  72         return 0;
  73 }
  74
  75 /**
  76  * frescan_bwres_negotiate()
  77  *
  78  * to negotiate a contract we follow the next steps:
  79  *
  80  * 1.- prepare a request
  81  * 2.- enqueue the request
  82  * 3.- wait in the reply object for a reply
  83  * 4.- return the final values and free the request
  84  *
  85  */
  86
  87 int frescan_bwres_negotiate(frescan_network_t net,
  88                             const frescan_contract_t *contract,
  89                             frescan_ss_t *id,
  90                             bool *accepted)
  91 {
  92         int ret;
  93         frescan_request_id_t   req;
  94         frescan_request_data_t *req_data;
  95         frescan_server_params_t server_params;
  96
  97         DEBUG(FRESCAN_BWRES_ENABLE_DEBUG, "preparing a negotiation request\n");
  98
  99         ret = frescan_requests_alloc(&req);
 100         if (ret != 0) return ret;
 101
 102         ret = frescan_requests_get_data(req, &req_data);
 103         if (ret != 0) return ret;
 104
 105         req_data->type         = FRESCAN_REQ_NEG;
 106         req_data->req          = req;
 107         req_data->contract     = (frescan_contract_t *)contract;
 108         req_data->request_node = the_networks[net].local_node;
 109         req_data->net          = net;
 110
 111         ret = frescan_bwres_robjs_alloc(&req_data->robj, FRESCAN_BWRES_MX_PRIO);
 112         if (ret != 0) return ret;
 113
 114         // NOTE: we preallocate a server for the negotiation process
 115         server_params.values.budget = contract->min_values.budget;
 116         server_params.values.period = contract->min_values.period;
 117         server_params.prio          = contract->prio;
 118
 119         ret = frescan_servers_create(net, &server_params, &req_data->ss);
 120         if (ret != 0) return ret;
 121
 122         DEBUG(FRESCAN_BWRES_ENABLE_DEBUG, "enqueue the negotiation request\n");
 123
 124         ret = frescan_requests_enqueue(req);
 125         if (ret != 0) return ret;
 126
 127         DEBUG(FRESCAN_BWRES_ENABLE_DEBUG, "wait for a reply\n");
 128
 129         ret = frescan_bwres_robjs_wait(req_data->robj);
 130         if (ret != 0) return ret;
 131
 132         ret = frescan_bwres_robjs_free(req_data->robj);
 133         if (ret != 0) return ret;
 134
 135         switch (req_data->return_value) {
 136                 case FRESCAN_REQ_ACCEPTED:
 137                         DEBUG(FRESCAN_BWRES_ENABLE_DEBUG, "negotiation OK\n");
 138                         *accepted = true;
 139                         *id = req_data->ss;
 140                         server_params.prio = req_data->final_values.server_prio;
 141                         ret = frescan_servers_update(net, &server_params, *id);
 142                         if (ret != 0) return ret;
 143                         break;
 144
 145                 case FRESCAN_REQ_NOT_ACCEPTED:
 146                         DEBUG(FRESCAN_BWRES_ENABLE_DEBUG, "negotiation FAIL\n");
 147                         *accepted = false;
 148                         ret = frescan_servers_destroy(net, req_data->ss);
 149                         if (ret != 0) return ret;
 150                         break;
 151
 152                 default:
 153                         ERROR("return_value unknown\n");
 154                         return -1;
 155         }
 156
 157         frescan_requests_free(req);
 158         return 0;
 159 }