tc/q_sfq.c

   1 /*
   2  * q_sfq.c              SFQ.
   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:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <syslog.h>
  17 #include <fcntl.h>
  18 #include <sys/socket.h>
  19 #include <netinet/in.h>
  20 #include <arpa/inet.h>
  21 #include <string.h>
  22 #include <math.h>
  23
  24 #include "utils.h"
  25 #include "tc_util.h"
  26 #include "tc_red.h"
  27
  28 static void explain(void)
  29 {
  30         fprintf(stderr, "Usage: ... sfq [ limit NUMBER ] [ perturb SECS ] [ quantum BYTES ]\n");
  31         fprintf(stderr, "               [ divisor NUMBER ] [ flows NUMBER] [ depth NUMBER ]\n");
  32         fprintf(stderr, "               [ headdrop ]\n");
  33         fprintf(stderr, "               [ redflowlimit BYTES ] [ min BYTES ] [ max BYTES ]\n");
  34         fprintf(stderr, "               [ avpkt BYTES ] [ burst PACKETS ] [ probability P ]\n");
  35         fprintf(stderr, "               [ ecn ] [ harddrop ]\n");
  36 }
  37
  38 static int sfq_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
  39 {
  40         int ok = 0, red = 0;
  41         struct tc_sfq_qopt_v1 opt = {};
  42         unsigned int burst = 0;
  43         int wlog;
  44         unsigned int avpkt = 1000;
  45         double probability = 0.02;
  46
  47         while (argc > 0) {
  48                 if (strcmp(*argv, "quantum") == 0) {
  49                         NEXT_ARG();
  50                         if (get_size(&opt.v0.quantum, *argv)) {
  51                                 fprintf(stderr, "Illegal \"limit\"\n");
  52                                 return -1;
  53                         }
  54                         ok++;
  55                 } else if (strcmp(*argv, "perturb") == 0) {
  56                         NEXT_ARG();
  57                         if (get_integer(&opt.v0.perturb_period, *argv, 0)) {
  58                                 fprintf(stderr, "Illegal \"perturb\"\n");
  59                                 return -1;
  60                         }
  61                         ok++;
  62                 } else if (strcmp(*argv, "limit") == 0) {
  63                         NEXT_ARG();
  64                         if (get_u32(&opt.v0.limit, *argv, 0)) {
  65                                 fprintf(stderr, "Illegal \"limit\"\n");
  66                                 return -1;
  67                         }
  68                         if (opt.v0.limit < 2) {
  69                                 fprintf(stderr, "Illegal \"limit\", must be > 1\n");
  70                                 return -1;
  71                         }
  72                         ok++;
  73                 } else if (strcmp(*argv, "divisor") == 0) {
  74                         NEXT_ARG();
  75                         if (get_u32(&opt.v0.divisor, *argv, 0)) {
  76                                 fprintf(stderr, "Illegal \"divisor\"\n");
  77                                 return -1;
  78                         }
  79                         ok++;
  80                 } else if (strcmp(*argv, "flows") == 0) {
  81                         NEXT_ARG();
  82                         if (get_u32(&opt.v0.flows, *argv, 0)) {
  83                                 fprintf(stderr, "Illegal \"flows\"\n");
  84                                 return -1;
  85                         }
  86                         ok++;
  87                 } else if (strcmp(*argv, "depth") == 0) {
  88                         NEXT_ARG();
  89                         if (get_u32(&opt.depth, *argv, 0)) {
  90                                 fprintf(stderr, "Illegal \"flows\"\n");
  91                                 return -1;
  92                         }
  93                         ok++;
  94                 } else if (strcmp(*argv, "headdrop") == 0) {
  95                         opt.headdrop = 1;
  96                         ok++;
  97                 } else if (strcmp(*argv, "redflowlimit") == 0) {
  98                         NEXT_ARG();
  99                         if (get_u32(&opt.limit, *argv, 0)) {
 100                                 fprintf(stderr, "Illegal \"redflowlimit\"\n");
 101                                 return -1;
 102                         }
 103                         red++;
 104                 } else if (strcmp(*argv, "min") == 0) {
 105                         NEXT_ARG();
 106                         if (get_u32(&opt.qth_min, *argv, 0)) {
 107                                 fprintf(stderr, "Illegal \"min\"\n");
 108                                 return -1;
 109                         }
 110                         red++;
 111                 } else if (strcmp(*argv, "max") == 0) {
 112                         NEXT_ARG();
 113                         if (get_u32(&opt.qth_max, *argv, 0)) {
 114                                 fprintf(stderr, "Illegal \"max\"\n");
 115                                 return -1;
 116                         }
 117                         red++;
 118                 } else if (strcmp(*argv, "burst") == 0) {
 119                         NEXT_ARG();
 120                         if (get_unsigned(&burst, *argv, 0)) {
 121                                 fprintf(stderr, "Illegal \"burst\"\n");
 122                                 return -1;
 123                         }
 124                         red++;
 125                 } else if (strcmp(*argv, "avpkt") == 0) {
 126                         NEXT_ARG();
 127                         if (get_size(&avpkt, *argv)) {
 128                                 fprintf(stderr, "Illegal \"avpkt\"\n");
 129                                 return -1;
 130                         }
 131                         red++;
 132                 } else if (strcmp(*argv, "probability") == 0) {
 133                         NEXT_ARG();
 134                         if (sscanf(*argv, "%lg", &probability) != 1) {
 135                                 fprintf(stderr, "Illegal \"probability\"\n");
 136                                 return -1;
 137                         }
 138                         red++;
 139                 } else if (strcmp(*argv, "ecn") == 0) {
 140                         opt.flags |= TC_RED_ECN;
 141                         red++;
 142                 } else if (strcmp(*argv, "harddrop") == 0) {
 143                         opt.flags |= TC_RED_HARDDROP;
 144                         red++;
 145                 } else if (strcmp(*argv, "help") == 0) {
 146                         explain();
 147                         return -1;
 148                 } else {
 149                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 150                         explain();
 151                         return -1;
 152                 }
 153                 argc--; argv++;
 154         }
 155         if (red) {
 156                 if (!opt.limit) {
 157                         fprintf(stderr, "Required parameter (redflowlimit) is missing\n");
 158                         return -1;
 159                 }
 160                 /* Compute default min/max thresholds based on
 161                    Sally Floyd's recommendations:
 162                    http://www.icir.org/floyd/REDparameters.txt
 163                 */
 164                 if (!opt.qth_max)
 165                         opt.qth_max = opt.limit / 4;
 166                 if (!opt.qth_min)
 167                         opt.qth_min = opt.qth_max / 3;
 168                 if (!burst)
 169                         burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 170
 171                 if (opt.qth_max > opt.limit) {
 172                         fprintf(stderr, "\"max\" is larger than \"limit\"\n");
 173                         return -1;
 174                 }
 175
 176                 if (opt.qth_min >= opt.qth_max) {
 177                         fprintf(stderr, "\"min\" is not smaller than \"max\"\n");
 178                         return -1;
 179                 }
 180
 181                 wlog = tc_red_eval_ewma(opt.qth_min, burst, avpkt);
 182                 if (wlog < 0) {
 183                         fprintf(stderr, "SFQ: failed to calculate EWMA constant.\n");
 184                         return -1;
 185                 }
 186                 if (wlog >= 10)
 187                         fprintf(stderr, "SFQ: WARNING. Burst %u seems to be too large.\n", burst);
 188                 opt.Wlog = wlog;
 189
 190                 wlog = tc_red_eval_P(opt.qth_min, opt.qth_max, probability);
 191                 if (wlog < 0) {
 192                         fprintf(stderr, "SFQ: failed to calculate probability.\n");
 193                         return -1;
 194                 }
 195                 opt.Plog = wlog;
 196                 opt.max_P = probability * pow(2, 32);
 197         }
 198
 199         if (ok || red)
 200                 addattr_l(n, 1024, TCA_OPTIONS, &opt, sizeof(opt));
 201         return 0;
 202 }
 203
 204 static int sfq_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 205 {
 206         struct tc_sfq_qopt *qopt;
 207         struct tc_sfq_qopt_v1 *qopt_ext = NULL;
 208
 209         SPRINT_BUF(b1);
 210         SPRINT_BUF(b2);
 211         SPRINT_BUF(b3);
 212         if (opt == NULL)
 213                 return 0;
 214
 215         if (RTA_PAYLOAD(opt)  < sizeof(*qopt))
 216                 return -1;
 217         if (RTA_PAYLOAD(opt) >= sizeof(*qopt_ext))
 218                 qopt_ext = RTA_DATA(opt);
 219         qopt = RTA_DATA(opt);
 220         fprintf(f, "limit %up ", qopt->limit);
 221         fprintf(f, "quantum %s ", sprint_size(qopt->quantum, b1));
 222         if (qopt_ext && qopt_ext->depth)
 223                 fprintf(f, "depth %u ", qopt_ext->depth);
 224         if (qopt_ext && qopt_ext->headdrop)
 225                 fprintf(f, "headdrop ");
 226
 227         if (show_details) {
 228                 fprintf(f, "flows %u/%u ", qopt->flows, qopt->divisor);
 229         }
 230         fprintf(f, "divisor %u ", qopt->divisor);
 231         if (qopt->perturb_period)
 232                 fprintf(f, "perturb %dsec ", qopt->perturb_period);
 233         if (qopt_ext && qopt_ext->qth_min) {
 234                 fprintf(f, "\n ewma %u ", qopt_ext->Wlog);
 235                 fprintf(f, "min %s max %s probability %g ",
 236                         sprint_size(qopt_ext->qth_min, b2),
 237                         sprint_size(qopt_ext->qth_max, b3),
 238                         qopt_ext->max_P / pow(2, 32));
 239                 if (qopt_ext->flags & TC_RED_ECN)
 240                         fprintf(f, "ecn ");
 241                 if (show_stats) {
 242                         fprintf(f, "\n prob_mark %u prob_mark_head %u prob_drop %u",
 243                                 qopt_ext->stats.prob_mark,
 244                                 qopt_ext->stats.prob_mark_head,
 245                                 qopt_ext->stats.prob_drop);
 246                         fprintf(f, "\n forced_mark %u forced_mark_head %u forced_drop %u",
 247                                 qopt_ext->stats.forced_mark,
 248                                 qopt_ext->stats.forced_mark_head,
 249                                 qopt_ext->stats.forced_drop);
 250                 }
 251         }
 252         return 0;
 253 }
 254
 255 static int sfq_print_xstats(struct qdisc_util *qu, FILE *f,
 256                             struct rtattr *xstats)
 257 {
 258         struct tc_sfq_xstats *st;
 259
 260         if (xstats == NULL)
 261                 return 0;
 262         if (RTA_PAYLOAD(xstats) < sizeof(*st))
 263                 return -1;
 264         st = RTA_DATA(xstats);
 265
 266         fprintf(f, " allot %d ", st->allot);
 267         fprintf(f, "\n");
 268         return 0;
 269 }
 270
 271 struct qdisc_util sfq_qdisc_util = {
 272         .id             = "sfq",
 273         .parse_qopt     = sfq_parse_opt,
 274         .print_qopt     = sfq_print_opt,
 275         .print_xstats   = sfq_print_xstats,
 276 };