blob: a234d2e017080274b272cda29d5941639d36f232 [file] [log] [blame]
/*
* q_choke.c CHOKE.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Stephen Hemminger <shemminger@vyatta.com>
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <syslog.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <math.h>
#include "utils.h"
#include "tc_util.h"
#include "tc_red.h"
static void explain(void)
{
fprintf(stderr, "Usage: ... choke limit PACKETS bandwidth KBPS [ecn]\n");
fprintf(stderr, " [ min PACKETS ] [ max PACKETS ] [ burst PACKETS ]\n");
}
static int choke_parse_opt(struct qdisc_util *qu, int argc, char **argv,
struct nlmsghdr *n)
{
struct tc_red_qopt opt = {};
unsigned int burst = 0;
unsigned int avpkt = 1000;
double probability = 0.02;
unsigned int rate = 0;
int ecn_ok = 0;
int wlog;
__u8 sbuf[256];
__u32 max_P;
struct rtattr *tail;
while (argc > 0) {
if (strcmp(*argv, "limit") == 0) {
NEXT_ARG();
if (get_unsigned(&opt.limit, *argv, 0)) {
fprintf(stderr, "Illegal \"limit\"\n");
return -1;
}
} else if (strcmp(*argv, "bandwidth") == 0) {
NEXT_ARG();
if (get_rate(&rate, *argv)) {
fprintf(stderr, "Illegal \"bandwidth\"\n");
return -1;
}
} else if (strcmp(*argv, "ecn") == 0) {
ecn_ok = 1;
} else if (strcmp(*argv, "min") == 0) {
NEXT_ARG();
if (get_unsigned(&opt.qth_min, *argv, 0)) {
fprintf(stderr, "Illegal \"min\"\n");
return -1;
}
} else if (strcmp(*argv, "max") == 0) {
NEXT_ARG();
if (get_unsigned(&opt.qth_max, *argv, 0)) {
fprintf(stderr, "Illegal \"max\"\n");
return -1;
}
} else if (strcmp(*argv, "burst") == 0) {
NEXT_ARG();
if (get_unsigned(&burst, *argv, 0)) {
fprintf(stderr, "Illegal \"burst\"\n");
return -1;
}
} else if (strcmp(*argv, "avpkt") == 0) {
NEXT_ARG();
if (get_size(&avpkt, *argv)) {
fprintf(stderr, "Illegal \"avpkt\"\n");
return -1;
}
} else if (strcmp(*argv, "probability") == 0) {
NEXT_ARG();
if (sscanf(*argv, "%lg", &probability) != 1) {
fprintf(stderr, "Illegal \"probability\"\n");
return -1;
}
} else if (strcmp(*argv, "help") == 0) {
explain();
return -1;
} else {
fprintf(stderr, "What is \"%s\"?\n", *argv);
explain();
return -1;
}
argc--; argv++;
}
if (!rate || !opt.limit) {
fprintf(stderr, "Required parameter (bandwidth, limit) is missing\n");
return -1;
}
/* Compute default min/max thresholds based on
Sally Floyd's recommendations:
http://www.icir.org/floyd/REDparameters.txt
*/
if (!opt.qth_max)
opt.qth_max = opt.limit / 4;
if (!opt.qth_min)
opt.qth_min = opt.qth_max / 3;
if (!burst)
burst = (2 * opt.qth_min + opt.qth_max) / 3;
if (opt.qth_max > opt.limit) {
fprintf(stderr, "\"max\" is larger than \"limit\"\n");
return -1;
}
if (opt.qth_min >= opt.qth_max) {
fprintf(stderr, "\"min\" is not smaller than \"max\"\n");
return -1;
}
wlog = tc_red_eval_ewma(opt.qth_min*avpkt, burst, avpkt);
if (wlog < 0) {
fprintf(stderr, "CHOKE: failed to calculate EWMA constant.\n");
return -1;
}
if (wlog >= 10)
fprintf(stderr, "CHOKE: WARNING. Burst %d seems to be too large.\n", burst);
opt.Wlog = wlog;
wlog = tc_red_eval_P(opt.qth_min*avpkt, opt.qth_max*avpkt, probability);
if (wlog < 0) {
fprintf(stderr, "CHOKE: failed to calculate probability.\n");
return -1;
}
opt.Plog = wlog;
wlog = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf);
if (wlog < 0) {
fprintf(stderr, "CHOKE: failed to calculate idle damping table.\n");
return -1;
}
opt.Scell_log = wlog;
if (ecn_ok)
opt.flags |= TC_RED_ECN;
tail = NLMSG_TAIL(n);
addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
addattr_l(n, 1024, TCA_CHOKE_PARMS, &opt, sizeof(opt));
addattr_l(n, 1024, TCA_CHOKE_STAB, sbuf, 256);
max_P = probability * pow(2, 32);
addattr_l(n, 1024, TCA_CHOKE_MAX_P, &max_P, sizeof(max_P));
tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
return 0;
}
static int choke_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
{
struct rtattr *tb[TCA_CHOKE_MAX+1];
const struct tc_red_qopt *qopt;
__u32 max_P = 0;
if (opt == NULL)
return 0;
parse_rtattr_nested(tb, TCA_CHOKE_MAX, opt);
if (tb[TCA_CHOKE_PARMS] == NULL)
return -1;
qopt = RTA_DATA(tb[TCA_CHOKE_PARMS]);
if (RTA_PAYLOAD(tb[TCA_CHOKE_PARMS]) < sizeof(*qopt))
return -1;
if (tb[TCA_CHOKE_MAX_P] &&
RTA_PAYLOAD(tb[TCA_CHOKE_MAX_P]) >= sizeof(__u32))
max_P = rta_getattr_u32(tb[TCA_CHOKE_MAX_P]);
fprintf(f, "limit %up min %up max %up ",
qopt->limit, qopt->qth_min, qopt->qth_max);
if (qopt->flags & TC_RED_ECN)
fprintf(f, "ecn ");
if (show_details) {
fprintf(f, "ewma %u ", qopt->Wlog);
if (max_P)
fprintf(f, "probability %g ", max_P / pow(2, 32));
else
fprintf(f, "Plog %u ", qopt->Plog);
fprintf(f, "Scell_log %u", qopt->Scell_log);
}
return 0;
}
static int choke_print_xstats(struct qdisc_util *qu, FILE *f,
struct rtattr *xstats)
{
struct tc_choke_xstats *st;
if (xstats == NULL)
return 0;
if (RTA_PAYLOAD(xstats) < sizeof(*st))
return -1;
st = RTA_DATA(xstats);
fprintf(f, " marked %u early %u pdrop %u other %u matched %u",
st->marked, st->early, st->pdrop, st->other, st->matched);
return 0;
}
struct qdisc_util choke_qdisc_util = {
.id = "choke",
.parse_qopt = choke_parse_opt,
.print_qopt = choke_print_opt,
.print_xstats = choke_print_xstats,
};