tc/q_gred.c

   1 /*
   2  * q_gred.c             GRED.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:    J Hadi Salim(hadi@nortelnetworks.com)
  10  *             code ruthlessly ripped from
  11  *             Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  12  *
  13  */
  14
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <unistd.h>
  18 #include <syslog.h>
  19 #include <fcntl.h>
  20 #include <sys/socket.h>
  21 #include <netinet/in.h>
  22 #include <arpa/inet.h>
  23 #include <string.h>
  24 #include <math.h>
  25
  26 #include "utils.h"
  27 #include "tc_util.h"
  28
  29 #include "tc_red.h"
  30
  31
  32 #if 0
  33 #define DPRINTF(format,args...) fprintf(stderr,format,##args)
  34 #else
  35 #define DPRINTF(format,args...)
  36 #endif
  37
  38 static void explain(void)
  39 {
  40         fprintf(stderr, "Usage: ... gred DP drop-probability limit BYTES "
  41             "min BYTES max BYTES\n");
  42         fprintf(stderr, "    avpkt BYTES burst PACKETS probability PROBABILITY "
  43             "bandwidth KBPS\n");
  44         fprintf(stderr, "    [prio value]\n");
  45         fprintf(stderr," OR ...\n");
  46         fprintf(stderr," gred setup DPs <num of DPs> default <default DP> "
  47             "[grio]\n");
  48 }
  49
  50 static int init_gred(struct qdisc_util *qu, int argc, char **argv,
  51                      struct nlmsghdr *n)
  52 {
  53
  54         struct rtattr *tail;
  55         struct tc_gred_sopt opt = { 0 };
  56
  57         opt.def_DP = MAX_DPs;
  58
  59         while (argc > 0) {
  60                 DPRINTF(stderr,"init_gred: invoked with %s\n",*argv);
  61                 if (strcmp(*argv, "DPs") == 0) {
  62                         NEXT_ARG();
  63                         if (get_unsigned(&opt.DPs, *argv, 10)) {
  64                                 fprintf(stderr, "Illegal \"DPs\"\n");
  65                                 return -1;
  66                         } else if (opt.DPs > MAX_DPs) {
  67                                 fprintf(stderr, "GRED: only %u DPs are "
  68                                         "currently supported\n", MAX_DPs);
  69                                 return -1;
  70                         }
  71                 } else if (strcmp(*argv, "default") == 0) {
  72                         if (opt.DPs == 0) {
  73                                 fprintf(stderr, "\"default\" must be defined "
  74                                         "after \"DPs\"\n");
  75                                 return -1;
  76                         }
  77                         NEXT_ARG();
  78                         if (get_unsigned(&opt.def_DP, *argv, 10)) {
  79                                 fprintf(stderr, "Illegal \"default\"\n");
  80                                 return -1;
  81                         } else if (opt.def_DP >= opt.DPs) {
  82                                 fprintf(stderr, "\"default\" must be less than "
  83                                         "\"DPs\"\n");
  84                                 return -1;
  85                         }
  86                 } else if (strcmp(*argv, "grio") == 0) {
  87                         opt.grio = 1;
  88                 } else if (strcmp(*argv, "help") == 0) {
  89                         explain();
  90                         return -1;
  91                 } else {
  92                         fprintf(stderr, "What is \"%s\"?\n", *argv);
  93                         explain();
  94                         return -1;
  95                 }
  96                 argc--; argv++;
  97         }
  98
  99         if (!opt.DPs || opt.def_DP == MAX_DPs) {
 100                 fprintf(stderr, "Illegal gred setup parameters \n");
 101                 return -1;
 102         }
 103
 104         DPRINTF("TC_GRED: sending DPs=%u def_DP=%u\n",opt.DPs,opt.def_DP);
 105         n->nlmsg_flags|=NLM_F_CREATE;
 106         tail = NLMSG_TAIL(n);
 107         addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
 108         addattr_l(n, 1024, TCA_GRED_DPS, &opt, sizeof(struct tc_gred_sopt));
 109         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 110         return 0;
 111 }
 112 /*
 113 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 114 */
 115 static int gred_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
 116 {
 117         int ok=0;
 118         struct tc_gred_qopt opt = { 0 };
 119         unsigned burst = 0;
 120         unsigned avpkt = 0;
 121         double probability = 0.02;
 122         unsigned rate = 0;
 123         int parm;
 124         __u8 sbuf[256];
 125         struct rtattr *tail;
 126         __u32 max_P;
 127
 128         opt.DP = MAX_DPs;
 129
 130         while (argc > 0) {
 131                 if (strcmp(*argv, "limit") == 0) {
 132                         NEXT_ARG();
 133                         if (get_size(&opt.limit, *argv)) {
 134                                 fprintf(stderr, "Illegal \"limit\"\n");
 135                                 return -1;
 136                         }
 137                         ok++;
 138                 } else if (strcmp(*argv, "setup") == 0) {
 139                         if (ok) {
 140                                 fprintf(stderr, "Illegal \"setup\"\n");
 141                                 return -1;
 142                         }
 143                         return init_gred(qu, argc-1, argv+1, n);
 144                 } else if (strcmp(*argv, "min") == 0) {
 145                         NEXT_ARG();
 146                         if (get_size(&opt.qth_min, *argv)) {
 147                                 fprintf(stderr, "Illegal \"min\"\n");
 148                                 return -1;
 149                         }
 150                         ok++;
 151                 } else if (strcmp(*argv, "max") == 0) {
 152                         NEXT_ARG();
 153                         if (get_size(&opt.qth_max, *argv)) {
 154                                 fprintf(stderr, "Illegal \"max\"\n");
 155                                 return -1;
 156                         }
 157                         ok++;
 158                 } else if (strcmp(*argv, "DP") == 0) {
 159                         NEXT_ARG();
 160                         if (get_unsigned(&opt.DP, *argv, 10)) {
 161                                 fprintf(stderr, "Illegal \"DP\"\n");
 162                                 return -1;
 163                         } else if (opt.DP >= MAX_DPs) {
 164                                 fprintf(stderr, "GRED: only %u DPs are "
 165                                         "currently supported\n", MAX_DPs);
 166                                 return -1;
 167                         } /* need a better error check */
 168                         ok++;
 169                 } else if (strcmp(*argv, "burst") == 0) {
 170                         NEXT_ARG();
 171                         if (get_unsigned(&burst, *argv, 0)) {
 172                                 fprintf(stderr, "Illegal \"burst\"\n");
 173                                 return -1;
 174                         }
 175                         ok++;
 176                 } else if (strcmp(*argv, "avpkt") == 0) {
 177                         NEXT_ARG();
 178                         if (get_size(&avpkt, *argv)) {
 179                                 fprintf(stderr, "Illegal \"avpkt\"\n");
 180                                 return -1;
 181                         }
 182                         ok++;
 183                 } else if (strcmp(*argv, "probability") == 0) {
 184                         NEXT_ARG();
 185                         if (sscanf(*argv, "%lg", &probability) != 1) {
 186                                 fprintf(stderr, "Illegal \"probability\"\n");
 187                                 return -1;
 188                         }
 189                         ok++;
 190                 } else if (strcmp(*argv, "prio") == 0) {
 191                         NEXT_ARG();
 192                         opt.prio=strtol(*argv, (char **)NULL, 10);
 193                         /* some error check here */
 194                         ok++;
 195                 } else if (strcmp(*argv, "bandwidth") == 0) {
 196                         NEXT_ARG();
 197                         if (get_rate(&rate, *argv)) {
 198                                 fprintf(stderr, "Illegal \"bandwidth\"\n");
 199                                 return -1;
 200                         }
 201                         ok++;
 202                 } else if (strcmp(*argv, "help") == 0) {
 203                         explain();
 204                         return -1;
 205                 } else {
 206                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 207                         explain();
 208                         return -1;
 209                 }
 210                 argc--; argv++;
 211         }
 212
 213         if (!ok) {
 214                 explain();
 215                 return -1;
 216         }
 217         if (opt.DP == MAX_DPs || !opt.limit || !opt.qth_min || !opt.qth_max ||
 218             !avpkt) {
 219                 fprintf(stderr, "Required parameter (DP, limit, min, max, "
 220                         "avpkt) is missing\n");
 221                 return -1;
 222         }
 223         if (!burst) {
 224                 burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 225                 fprintf(stderr, "GRED: set burst to %u\n", burst);
 226         }
 227         if (!rate) {
 228                 get_rate(&rate, "10Mbit");
 229                 fprintf(stderr, "GRED: set bandwidth to 10Mbit\n");
 230         }
 231         if ((parm = tc_red_eval_ewma(opt.qth_min, burst, avpkt)) < 0) {
 232                 fprintf(stderr, "GRED: failed to calculate EWMA constant.\n");
 233                 return -1;
 234         }
 235         if (parm >= 10)
 236                 fprintf(stderr, "GRED: WARNING. Burst %u seems to be too "
 237                     "large.\n", burst);
 238         opt.Wlog = parm;
 239         if ((parm = tc_red_eval_P(opt.qth_min, opt.qth_max, probability)) < 0) {
 240                 fprintf(stderr, "GRED: failed to calculate probability.\n");
 241                 return -1;
 242         }
 243         opt.Plog = parm;
 244         if ((parm = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf)) < 0)
 245             {
 246                 fprintf(stderr, "GRED: failed to calculate idle damping "
 247                     "table.\n");
 248                 return -1;
 249         }
 250         opt.Scell_log = parm;
 251
 252         tail = NLMSG_TAIL(n);
 253         addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
 254         addattr_l(n, 1024, TCA_GRED_PARMS, &opt, sizeof(opt));
 255         addattr_l(n, 1024, TCA_GRED_STAB, sbuf, 256);
 256         max_P = probability * pow(2, 32);
 257         addattr32(n, 1024, TCA_GRED_MAX_P, max_P);
 258         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 259         return 0;
 260 }
 261
 262 static int gred_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 263 {
 264         struct rtattr *tb[TCA_GRED_MAX + 1];
 265         struct tc_gred_sopt *sopt;
 266         struct tc_gred_qopt *qopt;
 267         __u32 *max_p = NULL;
 268         unsigned i;
 269         SPRINT_BUF(b1);
 270         SPRINT_BUF(b2);
 271         SPRINT_BUF(b3);
 272
 273         if (opt == NULL)
 274                 return 0;
 275
 276         parse_rtattr_nested(tb, TCA_GRED_MAX, opt);
 277
 278         if (tb[TCA_GRED_PARMS] == NULL)
 279                 return -1;
 280
 281         if (tb[TCA_GRED_MAX_P] &&
 282             RTA_PAYLOAD(tb[TCA_GRED_MAX_P]) >= sizeof(__u32) * MAX_DPs)
 283                 max_p = RTA_DATA(tb[TCA_GRED_MAX_P]);
 284
 285         sopt = RTA_DATA(tb[TCA_GRED_DPS]);
 286         qopt = RTA_DATA(tb[TCA_GRED_PARMS]);
 287         if (RTA_PAYLOAD(tb[TCA_GRED_DPS]) < sizeof(*sopt) ||
 288             RTA_PAYLOAD(tb[TCA_GRED_PARMS]) < sizeof(*qopt)*MAX_DPs) {
 289                 fprintf(f,"\n GRED received message smaller than expected\n");
 290                 return -1;
 291         }
 292
 293 /* Bad hack! should really return a proper message as shown above*/
 294
 295         fprintf(f, "DPs %u default %u %s",
 296                 sopt->DPs,
 297                 sopt->def_DP,
 298                 sopt->grio ? "grio " : "");
 299
 300         for (i=0;i<MAX_DPs;i++, qopt++) {
 301                 if (qopt->DP >= MAX_DPs) continue;
 302                 fprintf(f, "\n DP %u prio %hhu limit %s min %s max %s ",
 303                         qopt->DP,
 304                         qopt->prio,
 305                         sprint_size(qopt->limit, b1),
 306                         sprint_size(qopt->qth_min, b2),
 307                         sprint_size(qopt->qth_max, b3));
 308                 if (show_details) {
 309                         fprintf(f, "ewma %u ", qopt->Wlog);
 310                         if (max_p)
 311                                 fprintf(f, "probability %lg ", max_p[i] / pow(2, 32));
 312                         else
 313                                 fprintf(f, "Plog %u ", qopt->Plog);
 314                         fprintf(f, "Scell_log %u ", qopt->Scell_log);
 315                 }
 316                 if (show_stats) {
 317                         fprintf(f, "\n  Queue size: average %s current %s ",
 318                                 sprint_size(qopt->qave, b1),
 319                                 sprint_size(qopt->backlog, b2));
 320                         fprintf(f, "\n  Dropped packets: forced %u early %u pdrop %u other %u ",
 321                                 qopt->forced,
 322                                 qopt->early,
 323                                 qopt->pdrop,
 324                                 qopt->other);
 325                         fprintf(f, "\n  Total packets: %u (%s) ",
 326                                 qopt->packets,
 327                                 sprint_size(qopt->bytesin, b1));
 328                 }
 329         }
 330         return 0;
 331 }
 332
 333 struct qdisc_util gred_qdisc_util = {
 334         .id             = "gred",
 335         .parse_qopt     = gred_parse_opt,
 336         .print_qopt     = gred_print_opt,
 337 };