resources/disk_bfq/mngr/diskbfq_mngr.c

   1 /**************************************************************************/
   2 /* ---------------------------------------------------------------------- */
   3 /* Copyright (C) 2006 - 2008 FRESCOR consortium partners:                 */
   4 /*                                                                        */
   5 /*   Universidad de Cantabria,              SPAIN                         */
   6 /*   University of York,                    UK                            */
   7 /*   Scuola Superiore Sant'Anna,            ITALY                         */
   8 /*   Kaiserslautern University,             GERMANY                       */
   9 /*   Univ. Politécnica  Valencia,           SPAIN                        */
  10 /*   Czech Technical University in Prague,  CZECH REPUBLIC                */
  11 /*   ENEA                                   SWEDEN                        */
  12 /*   Thales Communication S.A.              FRANCE                        */
  13 /*   Visual Tools S.A.                      SPAIN                         */
  14 /*   Rapita Systems Ltd                     UK                            */
  15 /*   Evidence                               ITALY                         */
  16 /*                                                                        */
  17 /*   See http://www.frescor.org for a link to partners' websites          */
  18 /*                                                                        */
  19 /*          FRESCOR project (FP6/2005/IST/5-034026) is funded             */
  20 /*       in part by the European Union Sixth Framework Programme          */
  21 /*       The European Union is not liable of any use that may be          */
  22 /*       made of this code.                                               */
  23 /*                                                                        */
  24 /*                                                                        */
  25 /*  This file is part of FRESCOR BFQ disk bandwidth reservation           */
  26 /*                                                                        */
  27 /* FWP is free software; you can redistribute it and/or modify it         */
  28 /* under terms of the GNU General Public License as published by the      */
  29 /* Free Software Foundation; either version 2, or (at your option) any    */
  30 /* later version.  FWP is distributed in the hope that it will be         */
  31 /* useful, but WITHOUT ANY WARRANTY; without even the implied warranty    */
  32 /* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU    */
  33 /* General Public License for more details. You should have received a    */
  34 /* copy of the GNU General Public License along with FWP; see file        */
  35 /* COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,  */
  36 /* Cambridge, MA 02139, USA.                                              */
  37 /*                                                                        */
  38 /* As a special exception, including FWP header files in a file,          */
  39 /* instantiating FWP generics or templates, or linking other files        */
  40 /* with FWP objects to produce an executable application, does not        */
  41 /* by itself cause the resulting executable application to be covered     */
  42 /* by the GNU General Public License. This exception does not             */
  43 /* however invalidate any other reasons why the executable file might be  */
  44 /* covered by the GNU Public License.                                     */
  45 /**************************************************************************/
  46 #include <frm_generic.h>
  47 #include <forb.h>
  48 #include <error.h>
  49 #include <errno.h>
  50 #include <fres_sa_scenario.h>
  51 #include <stdbool.h>
  52 #include <ul_log.h>
  53 #include <stdio.h>
  54 #include <math.h>
  55 #include "res_disk.h"
  56
  57 UL_LOG_CUST(ulogd_frm_diskbfq);
  58 ul_log_domain_t ulogd_fra_fwp = {UL_LOGL_DEB, "frm_diskbfq"};
  59
  60 struct disk_data {
  61         long throughput;
  62         int budget;
  63 };
  64
  65 static int bandwidth_to_weight(struct disk_data *data,
  66                                unsigned long budget,
  67                                unsigned long period)
  68 {
  69         float th, weight;
  70         //unsigned long q_i, p_i;
  71         int b, w_i;
  72
  73         th = data->throughput / 10E9;
  74         b = data->budget;
  75
  76         /* Convert to nanoseconds! */
  77         //q_i *= 1000;
  78         //p_i *= 1000;
  79
  80         if (period < b / th)
  81                 return -1;
  82
  83         weight = (DISKBFQ_WEIGHT_MAX * budget) / (period - (b / th));
  84         w_i = floor(weight);
  85         if (weight != w_i)
  86                 w_i++;
  87
  88         return w_i;
  89 }
  90
  91 static int weight_to_ioprio(int weight)
  92 {
  93         if (weight >= 100)
  94                 return 0;
  95         if (weight > 14)
  96                 return 1;
  97         if (weight == -1)
  98                 return -1;
  99
 100         return 8 - 1 - (weight / 2);
 101 }
 102
 103 static int diskbfq_admtest(struct fres_sa_scenario *scenario,
 104                            void *priv,
 105                            bool *schedulable)
 106 {
 107         struct fres_sa_contract *c;
 108         long int period, budget;
 109         long int sum_weight = 0;
 110         struct disk_data *data = priv;
 111
 112         fres_sa_scenario_for_each_contract(scenario, c) {
 113                 fres_block_basic *basic;
 114                 fres_block_resource *resource;
 115                 fres_block_disk_sched *disk_sched;
 116                 char id[40];
 117
 118                 fres_contract_id_to_string(id, &c->contract->id, sizeof(id));
 119                 basic = fres_contract_get_basic(c->contract);
 120                 resource = fres_contract_get_resource(c->contract);
 121
 122                 period = fosa_rel_time_to_nsec(basic->period);
 123                 budget = fosa_rel_time_to_nsec(basic->budget);
 124                 printf("processing: id=%s, period=%ld ms, budget=%ld ms\n",
 125                        id, period, budget);
 126
 127                 if (c->contract == c->new) {
 128                         int ret;
 129
 130                         /* Calc weight and IO prio for the new contracts */
 131                         disk_sched = malloc(sizeof(*disk_sched));
 132                         if (!disk_sched) return -1;
 133
 134                         disk_sched->weight = bandwidth_to_weight(data,
 135                                                                  budget,
 136                                                                  period);
 137                         disk_sched->ioprio =
 138                                 weight_to_ioprio(disk_sched->weight);
 139                         ret = fres_contract_add_disk_sched(c->contract,
 140                                                            disk_sched);
 141                         if (ret) {
 142                                 fprintf(stderr,
 143                                         "Cannot add disk_sched block\n");
 144                                 free(disk_sched);
 145                                 return -1;
 146                         }
 147                 } else {
 148                         disk_sched = fres_contract_get_disk_sched(c->contract);
 149                         if (!disk_sched) {
 150                                 fprintf(stderr,
 151                                         "disk_sched is not present\n");
 152                                 return -1;
 153                         }
 154                 }
 155                 sum_weight += disk_sched->weight;
 156         }
 157
 158         printf("sum_weight=%ld, max_weight=%d\n",
 159                sum_weight,
 160                DISKBFQ_WEIGHT_MAX);
 161         *schedulable = sum_weight < DISKBFQ_WEIGHT_MAX;
 162         printf("=>%s\n", (*schedulable) ? "schedulable" : "not schedulable");
 163
 164         return 0;
 165 }
 166
 167 struct disk_data disk;
 168
 169 static struct fres_res_manager frm = {
 170         .res_type = FRSH_RT_DISK,
 171         .res_id = 0,
 172         .admission_test = diskbfq_admtest,
 173         .priv = &disk
 174 };
 175
 176 int main(int argc, char *argv[])
 177 {
 178         forb_orb orb;
 179         FILE* fd;
 180         char disk_name[40];
 181         char path[128], scheduler[128];
 182         int opt, ret;
 183
 184         if (argc < 3) {
 185 err_usage:
 186                 fprintf(stderr, "Usage:\n %s -i disk_id -d disk_dev_name\n",
 187                         argv[0]);
 188                 error(1, EINVAL, "frm_diskbfq");
 189         }
 190
 191         while ((opt = getopt(argc, argv, "i:d:")) != -1) {
 192                 switch (opt) {
 193                         case 'i':
 194                                 frm.res_id = atoi(optarg);
 195                                 break;
 196                         case 'd':
 197                                 strncpy(disk_name,
 198                                         optarg, sizeof(disk_name));
 199                                 break;
 200                         default:
 201                                 goto err_usage;
 202                 }
 203         }
 204
 205         orb = forb_init(&argc, &argv, "frm_diskbfq");
 206         if (!orb) error(1, errno, "forb_init");
 207
 208         /*
 209          * Check if BFQ I/O scheduler is available
 210          *  in the system.
 211          */
 212         snprintf(path, 128,
 213                  SYSFS_BFQ_SCHED_PATH,
 214                  disk_name);
 215         if (!(fd = fopen(path, "rw")))
 216                 error(1, errno, "frm_generic_run");
 217
 218         ret = fscanf(fd, "%128[^\n]", scheduler);
 219         if (ret == 0 || ret == EOF)
 220                 error(1, errno, "frm_generic_run");
 221         if (!strstr(scheduler, SYSFS_BFQ_NAME))
 222                 error(1, errno, "frm_generic_run");
 223
 224         /*
 225          * Now check if BFQ is the default I/O scheduler
 226          *  for the specific disk and set it to so if not.
 227          */
 228         else if (!strstr(scheduler, "[" SYSFS_BFQ_NAME "]")) {
 229                 rewind(fd);
 230                 ret = fprintf(fd, SYSFS_BFQ_NAME);
 231                 if (ret && ret != EOF)
 232                         ret = fflush(fd);
 233                 if (ret == 0 || ret == EOF)
 234                         error(1, errno, "frm_generic_run");
 235         }
 236         fclose(fd);
 237
 238         snprintf(path, sizeof(path),
 239                  SYSFS_BFQ_BUDGET_PATH,
 240                  disk_name);
 241         if (!(fd = fopen(path, "r")))
 242                 error(1, errno, "frm_generic_run");
 243
 244         ret = fscanf(fd, "%d", &disk.budget);
 245         if (ret == 0 || ret == EOF)
 246                 error(1, errno, "frm_generic_run");
 247         fclose(fd);
 248
 249         /*
 250          * TODO:
 251          *  run the benchmark to get the throughput.
 252          */
 253         disk.throughput = 100000;
 254
 255         fprintf(stdout, "disk name: %s\n"
 256                 "scheduler: %s\n"
 257                 "disk aggregate throughput: %ld\n"
 258                 "scheduling budget: %d\n",
 259                 disk_name, SYSFS_BFQ_NAME, disk.throughput, disk.budget);
 260
 261         /* Register fres_block_disk_sched to contract handling
 262          *  functions */
 263         fres_block_register_disk_sched();
 264
 265         ret = frm_register_and_run(orb, &frm);
 266         if (ret) error(1, errno, "frm_generic_run");
 267
 268         return 0;
 269 }
 270