src/frsh/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 <ul_logreg.h>
  54 #include <stdio.h>
  55 #include <math.h>
  56
  57 #include "res_disk.h"
  58 #include "diskbfq_th.h"
  59
  60 UL_LOG_CUST(ulogd_frm_diskbfq);
  61 ul_log_domain_t ulogd_frm_diskbfq = {UL_LOGL_DEB, "frm_diskbfq"};
  62
  63 struct disk_data {
  64         double throughput;
  65         int budget;
  66 };
  67
  68 static int bandwidth_to_weight(struct disk_data *data,
  69                                unsigned long budget,
  70                                unsigned long period)
  71 {
  72         float th, weight;
  73         //unsigned long q_i, p_i;
  74         int b, w_i;
  75
  76         th = data->throughput / 10E9;
  77         b = data->budget;
  78
  79         /* Convert to nanoseconds! */
  80         //q_i *= 1000;
  81         //p_i *= 1000;
  82
  83         if (period < b / th)
  84                 return -1;
  85
  86         weight = (DISKBFQ_WEIGHT_MAX * budget) / (period - (b / th));
  87         w_i = floor(weight);
  88         if (weight != w_i)
  89                 w_i++;
  90
  91         return w_i;
  92 }
  93
  94 static int weight_to_ioprio(int weight)
  95 {
  96         if (weight >= 100)
  97                 return 0;
  98         if (weight > 14)
  99                 return 1;
 100         if (weight == -1)
 101                 return -1;
 102
 103         return 8 - 1 - (weight / 2);
 104 }
 105
 106 static int diskbfq_admtest(struct fres_sa_scenario *scenario,
 107                            void *priv,
 108                            bool *schedulable)
 109 {
 110         struct fres_sa_contract *c;
 111         long int period, budget;
 112         long int sum_weight = 0;
 113         struct disk_data *data = priv;
 114
 115         fres_sa_scenario_for_each_no_cancel_contract(scenario, c) {
 116                 fres_block_basic *basic;
 117                 fres_block_resource *resource;
 118                 fres_block_disk_sched *disk_sched;
 119                 char id[40];
 120
 121                 fres_contract_id_to_string(id, &c->contract->id, sizeof(id));
 122                 basic = fres_contract_get_basic(c->contract);
 123                 resource = fres_contract_get_resource(c->contract);
 124
 125                 period = fosa_rel_time_to_nsec(basic->period);
 126                 budget = fosa_rel_time_to_nsec(basic->budget);
 127                 ul_logmsg("processing: id=%s, period=%ld us, budget=%ld us\n",
 128                        id, period/1000, budget/1000);
 129
 130                 if (c->contract == c->new) {
 131                         int ret;
 132
 133                         /* Calc weight and IO prio for the new contracts */
 134                         disk_sched = malloc(sizeof(*disk_sched));
 135                         if (!disk_sched) return -1;
 136
 137                         disk_sched->weight = bandwidth_to_weight(data,
 138                                                                  budget,
 139                                                                  period);
 140                         disk_sched->ioprio =
 141                                 weight_to_ioprio(disk_sched->weight);
 142                         ret = fres_contract_add_disk_sched(c->contract,
 143                                                            disk_sched);
 144                         if (ret) {
 145                                 ul_logerr("Cannot add disk_sched block\n");
 146                                 free(disk_sched);
 147                                 return -1;
 148                         }
 149                 } else {
 150                         disk_sched = fres_contract_get_disk_sched(c->contract);
 151                         if (!disk_sched) {
 152                                 ul_logerr("disk_sched is not present\n");
 153                                 return -1;
 154                         }
 155                 }
 156                 sum_weight += disk_sched->weight;
 157         }
 158
 159         ul_logmsg("sum_weight=%ld, max_weight=%d\n",
 160                   sum_weight,
 161                   DISKBFQ_WEIGHT_MAX);
 162         *schedulable = sum_weight < DISKBFQ_WEIGHT_MAX;
 163         ul_logmsg("=> %s\n", (*schedulable) ? "schedulable" : "not schedulable");
 164
 165         return 0;
 166 }
 167
 168 struct disk_data disk;
 169
 170 static struct fres_res_manager frm = {
 171         .res_type = FRSH_RT_DISK,
 172         .res_id = 0,
 173         .name = "Disk BFQ",
 174         .admission_test = diskbfq_admtest,
 175         .priv = &disk
 176 };
 177
 178 int forb_main(forb_orb orb, int argc, char *argv[])
 179 {
 180         FILE* fd;
 181         int readers = 4;
 182         char disk_dev[40] = {0}, *disk_name = disk_dev;
 183         char path[128], scheduler[128];
 184         int i, opt, ret;
 185
 186         ul_logreg_domain(&ulogd_frm_diskbfq);
 187
 188         if (argc < 3) {
 189 err_usage:
 190                 fprintf(stderr, "Usage:\n %s "
 191                         "-i disk_id -d disk_device [-n readers]\n",
 192                         argv[0]);
 193                 error(1, EINVAL, "frm_diskbfq");
 194         }
 195
 196         while ((opt = getopt(argc, argv, "i:d:n:")) != -1) {
 197                 switch (opt) {
 198                         case 'i':
 199                                 frm.res_id = atoi(optarg);
 200                                 break;
 201                         case 'd':
 202                                 strncpy(disk_dev,
 203                                         optarg, sizeof(disk_dev));
 204
 205                                 for (i = strlen(disk_dev) - 1; i >= 0; i--) {
 206                                         if (disk_dev[i] == '/') {
 207                                                 disk_name = disk_dev + i + 1;
 208                                                 break;
 209                                         }
 210                                 }
 211                                 break;
 212                         case 'n':
 213                                 readers = atoi(optarg);
 214                                 break;
 215                         default:
 216                                 goto err_usage;
 217                 }
 218         }
 219
 220         if (!*disk_name)
 221                 error(1, 0, "Disk device not specified");
 222
 223         /*
 224          * Check if BFQ I/O scheduler is available
 225          *  in the system.
 226          */
 227         snprintf(path, 128,
 228                  SYSFS_BFQ_SCHED_PATH,
 229                  disk_name);
 230         if (!(fd = fopen(path, "r+")))
 231                 error(1, errno, "fopen(%s)", path);
 232
 233         ret = fscanf(fd, "%128[^\n]", scheduler);
 234         if (ret == 0 || ret == EOF)
 235                 error(1, errno, "fscanf: %s", path);
 236         if (!strstr(scheduler, SYSFS_BFQ_NAME))
 237                 error(1, errno, "bfq not available in kernel");
 238
 239         /**
 240          * Now check if BFQ is the default I/O scheduler
 241          *  for the specific disk and set it to so if not.
 242          **/
 243         else if (!strstr(scheduler, "[" SYSFS_BFQ_NAME "]")) {
 244                 rewind(fd);
 245                 ret = fprintf(fd, SYSFS_BFQ_NAME);
 246                 if (ret && ret != EOF)
 247                         ret = fflush(fd);
 248                 if (ret == 0 || ret == EOF)
 249                         error(1, errno, "cannot activate bfq scheduler");
 250         }
 251         fclose(fd);
 252
 253         snprintf(path, sizeof(path),
 254                  SYSFS_BFQ_BUDGET_PATH,
 255                  disk_name);
 256         if (!(fd = fopen(path, "r+")))
 257                 error(1, errno, "fopen(%s)", path);
 258
 259         ret = fprintf(fd, "256");
 260         if (ret == 0)
 261                 error(1, errno, "fprintf: %s", path);
 262
 263         rewind(fd);
 264         ret = fscanf(fd, "%d", &disk.budget);
 265         if (ret == 0 || ret == EOF)
 266                 error(1, errno, "fscanf: %s", path);
 267         fclose(fd);
 268
 269         /**
 270          * Estimate the disk throughput in order to achieve
 271          *  effective weight assignement during runtime.
 272          **/
 273         printf("Throughput estimation...\n");
 274         disk.throughput = estimate_throughput(disk_dev, readers);
 275         if (disk.throughput < 0.0)
 276                 error(1, errno, "throughput estimation error");
 277
 278         fprintf(stdout, "disk name: %s\n"
 279                 "scheduler: %s\n"
 280                 "disk aggregate throughput: %f KiB/s\n"
 281                 "scheduling budget: %d\n",
 282                 disk_name, SYSFS_BFQ_NAME, disk.throughput, disk.budget);
 283
 284         /* Register fres_block_disk_sched to contract handling
 285          *  functions */
 286         fres_block_register_disk_sched();
 287
 288         ret = frm_register_and_run(orb, &frm);
 289         if (ret) error(1, errno, "frm_register_and_run");
 290
 291         return 0;
 292 }
 293