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         memset(&opt, 0, sizeof(opt));
  48
  49         while (argc > 0) {
  50                 if (strcmp(*argv, "quantum") == 0) {
  51                         NEXT_ARG();
  52                         if (get_size(&opt.v0.quantum, *argv)) {
  53                                 fprintf(stderr, "Illegal \"limit\"\n");
  54                                 return -1;
  55                         }
  56                         ok++;
  57                 } else if (strcmp(*argv, "perturb") == 0) {
  58                         NEXT_ARG();
  59                         if (get_integer(&opt.v0.perturb_period, *argv, 0)) {
  60                                 fprintf(stderr, "Illegal \"perturb\"\n");
  61                                 return -1;
  62                         }
  63                         ok++;
  64                 } else if (strcmp(*argv, "limit") == 0) {
  65                         NEXT_ARG();
  66                         if (get_u32(&opt.v0.limit, *argv, 0)) {
  67                                 fprintf(stderr, "Illegal \"limit\"\n");
  68                                 return -1;
  69                         }
  70                         if (opt.v0.limit < 2) {
  71                                 fprintf(stderr, "Illegal \"limit\", must be > 1\n");
  72                                 return -1;
  73                         }
  74                         ok++;
  75                 } else if (strcmp(*argv, "divisor") == 0) {
  76                         NEXT_ARG();
  77                         if (get_u32(&opt.v0.divisor, *argv, 0)) {
  78                                 fprintf(stderr, "Illegal \"divisor\"\n");
  79                                 return -1;
  80                         }
  81                         ok++;
  82                 } else if (strcmp(*argv, "flows") == 0) {
  83                         NEXT_ARG();
  84                         if (get_u32(&opt.v0.flows, *argv, 0)) {
  85                                 fprintf(stderr, "Illegal \"flows\"\n");
  86                                 return -1;
  87                         }
  88                         ok++;
  89                 } else if (strcmp(*argv, "depth") == 0) {
  90                         NEXT_ARG();
  91                         if (get_u32(&opt.depth, *argv, 0)) {
  92                                 fprintf(stderr, "Illegal \"flows\"\n");
  93                                 return -1;
  94                         }
  95                         ok++;
  96                 } else if (strcmp(*argv, "headdrop") == 0) {
  97                         opt.headdrop = 1;
  98                         ok++;
  99                 } else if (strcmp(*argv, "redflowlimit") == 0) {
 100                         NEXT_ARG();
 101                         if (get_u32(&opt.limit, *argv, 0)) {
 102                                 fprintf(stderr, "Illegal \"redflowlimit\"\n");
 103                                 return -1;
 104                         }
 105                         red++;
 106                 } else if (strcmp(*argv, "min") == 0) {
 107                         NEXT_ARG();
 108                         if (get_u32(&opt.qth_min, *argv, 0)) {
 109                                 fprintf(stderr, "Illegal \"min\"\n");
 110                                 return -1;
 111                         }
 112                         red++;
 113                 } else if (strcmp(*argv, "max") == 0) {
 114                         NEXT_ARG();
 115                         if (get_u32(&opt.qth_max, *argv, 0)) {
 116                                 fprintf(stderr, "Illegal \"max\"\n");
 117                                 return -1;
 118                         }
 119                         red++;
 120                 } else if (strcmp(*argv, "burst") == 0) {
 121                         NEXT_ARG();
 122                         if (get_unsigned(&burst, *argv, 0)) {
 123                                 fprintf(stderr, "Illegal \"burst\"\n");
 124                                 return -1;
 125                         }
 126                         red++;
 127                 } else if (strcmp(*argv, "avpkt") == 0) {
 128                         NEXT_ARG();
 129                         if (get_size(&avpkt, *argv)) {
 130                                 fprintf(stderr, "Illegal \"avpkt\"\n");
 131                                 return -1;
 132                         }
 133                         red++;
 134                 } else if (strcmp(*argv, "probability") == 0) {
 135                         NEXT_ARG();
 136                         if (sscanf(*argv, "%lg", &probability) != 1) {
 137                                 fprintf(stderr, "Illegal \"probability\"\n");
 138                                 return -1;
 139                         }
 140                         red++;
 141                 } else if (strcmp(*argv, "ecn") == 0) {
 142                         opt.flags |= TC_RED_ECN;
 143                         red++;
 144                 } else if (strcmp(*argv, "harddrop") == 0) {
 145                         opt.flags |= TC_RED_HARDDROP;
 146                         red++;
 147                 } else if (strcmp(*argv, "help") == 0) {
 148                         explain();
 149                         return -1;
 150                 } else {
 151                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 152                         explain();
 153                         return -1;
 154                 }
 155                 argc--; argv++;
 156         }
 157         if (red) {
 158                 if (!opt.limit) {
 159                         fprintf(stderr, "Required parameter (redflowlimit) is missing\n");
 160                         return -1;
 161                 }
 162                 /* Compute default min/max thresholds based on
 163                    Sally Floyd's recommendations:
 164                    http://www.icir.org/floyd/REDparameters.txt
 165                 */
 166                 if (!opt.qth_max)
 167                         opt.qth_max = opt.limit / 4;
 168                 if (!opt.qth_min)
 169                         opt.qth_min = opt.qth_max / 3;
 170                 if (!burst)
 171                         burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 172
 173                 if (opt.qth_max > opt.limit) {
 174                         fprintf(stderr, "\"max\" is larger than \"limit\"\n");
 175                         return -1;
 176                 }
 177
 178                 if (opt.qth_min >= opt.qth_max) {
 179                         fprintf(stderr, "\"min\" is not smaller than \"max\"\n");
 180                         return -1;
 181                 }
 182
 183                 wlog = tc_red_eval_ewma(opt.qth_min, burst, avpkt);
 184                 if (wlog < 0) {
 185                         fprintf(stderr, "SFQ: failed to calculate EWMA constant.\n");
 186                         return -1;
 187                 }
 188                 if (wlog >= 10)
 189                         fprintf(stderr, "SFQ: WARNING. Burst %u seems to be too large.\n", burst);
 190                 opt.Wlog = wlog;
 191
 192                 wlog = tc_red_eval_P(opt.qth_min, opt.qth_max, probability);
 193                 if (wlog < 0) {
 194                         fprintf(stderr, "SFQ: failed to calculate probability.\n");
 195                         return -1;
 196                 }
 197                 opt.Plog = wlog;
 198                 opt.max_P = probability * pow(2, 32);
 199         }
 200
 201         if (ok || red)
 202                 addattr_l(n, 1024, TCA_OPTIONS, &opt, sizeof(opt));
 203         return 0;
 204 }
 205
 206 static int sfq_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 207 {
 208         struct tc_sfq_qopt *qopt;
 209         struct tc_sfq_qopt_v1 *qopt_ext = NULL;
 210         SPRINT_BUF(b1);
 211         SPRINT_BUF(b2);
 212         SPRINT_BUF(b3);
 213         if (opt == NULL)
 214                 return 0;
 215
 216         if (RTA_PAYLOAD(opt)  < sizeof(*qopt))
 217                 return -1;
 218         if (RTA_PAYLOAD(opt) >= sizeof(*qopt_ext))
 219                 qopt_ext = RTA_DATA(opt);
 220         qopt = RTA_DATA(opt);
 221         fprintf(f, "limit %up ", qopt->limit);
 222         fprintf(f, "quantum %s ", sprint_size(qopt->quantum, b1));
 223         if (qopt_ext && qopt_ext->depth)
 224                 fprintf(f, "depth %u ", qopt_ext->depth);
 225         if (qopt_ext && qopt_ext->headdrop)
 226                 fprintf(f, "headdrop ");
 227
 228         if (show_details) {
 229                 fprintf(f, "flows %u/%u ", qopt->flows, qopt->divisor);
 230         }
 231         fprintf(f, "divisor %u ", qopt->divisor);
 232         if (qopt->perturb_period)
 233                 fprintf(f, "perturb %dsec ", qopt->perturb_period);
 234         if (qopt_ext && qopt_ext->qth_min) {
 235                 fprintf(f, "\n ewma %u ", qopt_ext->Wlog);
 236                 fprintf(f, "min %s max %s probability %g ",
 237                         sprint_size(qopt_ext->qth_min, b2),
 238                         sprint_size(qopt_ext->qth_max, b3),
 239                         qopt_ext->max_P / pow(2, 32));
 240                 if (qopt_ext->flags & TC_RED_ECN)
 241                         fprintf(f, "ecn ");
 242                 if (show_stats) {
 243                         fprintf(f, "\n prob_mark %u prob_mark_head %u prob_drop %u",
 244                                 qopt_ext->stats.prob_mark,
 245                                 qopt_ext->stats.prob_mark_head,
 246                                 qopt_ext->stats.prob_drop);
 247                         fprintf(f, "\n forced_mark %u forced_mark_head %u forced_drop %u",
 248                                 qopt_ext->stats.forced_mark,
 249                                 qopt_ext->stats.forced_mark_head,
 250                                 qopt_ext->stats.forced_drop);
 251                 }
 252         }
 253         return 0;
 254 }
 255
 256 static int sfq_print_xstats(struct qdisc_util *qu, FILE *f,
 257                             struct rtattr *xstats)
 258 {
 259         struct tc_sfq_xstats *st;
 260
 261         if (xstats == NULL)
 262                 return 0;
 263         if (RTA_PAYLOAD(xstats) < sizeof(*st))
 264                 return -1;
 265         st = RTA_DATA(xstats);
 266
 267         fprintf(f, " allot %d ", st->allot);
 268         fprintf(f, "\n");
 269         return 0;
 270 }
 271
 272 struct qdisc_util sfq_qdisc_util = {
 273         .id             = "sfq",
 274         .parse_qopt     = sfq_parse_opt,
 275         .print_qopt     = sfq_print_opt,
 276         .print_xstats   = sfq_print_xstats,
 277 };