iproute2/tc/q_etf.c
Vinicius Costa Gomes 7da5ef2200 tc: Add support for the ETF Qdisc
The "Earliest TxTime First" (ETF) queueing discipline allows precise
control of the transmission time of packets by providing a sorted
time-based scheduling of packets.

The syntax is:

tc qdisc add dev DEV parent NODE etf delta <DELTA>
                     clockid <CLOCKID> [offload] [deadline_mode]

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
2018-07-11 17:50:10 -07:00

182 lines
4.4 KiB
C

/*
* q_etf.c Earliest TxTime First (ETF).
*
* 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: Vinicius Costa Gomes <vinicius.gomes@intel.com>
* Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include "utils.h"
#include "tc_util.h"
#define CLOCKID_INVALID (-1)
static const struct static_clockid {
const char *name;
clockid_t clockid;
} clockids_sysv[] = {
{ "REALTIME", CLOCK_REALTIME },
{ "TAI", CLOCK_TAI },
{ "BOOTTIME", CLOCK_BOOTTIME },
{ "MONOTONIC", CLOCK_MONOTONIC },
{ NULL }
};
static void explain(void)
{
fprintf(stderr, "Usage: ... etf delta NANOS clockid CLOCKID [offload] [deadline_mode]\n");
fprintf(stderr, "CLOCKID must be a valid SYS-V id (i.e. CLOCK_TAI)\n");
}
static void explain1(const char *arg, const char *val)
{
fprintf(stderr, "etf: illegal value for \"%s\": \"%s\"\n", arg, val);
}
static void explain_clockid(const char *val)
{
fprintf(stderr, "etf: illegal value for \"clockid\": \"%s\".\n", val);
fprintf(stderr, "It must be a valid SYS-V id (i.e. CLOCK_TAI)\n");
}
static int get_clockid(__s32 *val, const char *arg)
{
const struct static_clockid *c;
/* Drop the CLOCK_ prefix if that is being used. */
if (strcasestr(arg, "CLOCK_") != NULL)
arg += sizeof("CLOCK_") - 1;
for (c = clockids_sysv; c->name; c++) {
if (strcasecmp(c->name, arg) == 0) {
*val = c->clockid;
return 0;
}
}
return -1;
}
static const char* get_clock_name(clockid_t clockid)
{
const struct static_clockid *c;
for (c = clockids_sysv; c->name; c++) {
if (clockid == c->clockid)
return c->name;
}
return "invalid";
}
static int etf_parse_opt(struct qdisc_util *qu, int argc,
char **argv, struct nlmsghdr *n, const char *dev)
{
struct tc_etf_qopt opt = {
.clockid = CLOCKID_INVALID,
};
struct rtattr *tail;
while (argc > 0) {
if (matches(*argv, "offload") == 0) {
if (opt.flags & TC_ETF_OFFLOAD_ON) {
fprintf(stderr, "etf: duplicate \"offload\" specification\n");
return -1;
}
opt.flags |= TC_ETF_OFFLOAD_ON;
} else if (matches(*argv, "deadline_mode") == 0) {
if (opt.flags & TC_ETF_DEADLINE_MODE_ON) {
fprintf(stderr, "etf: duplicate \"deadline_mode\" specification\n");
return -1;
}
opt.flags |= TC_ETF_DEADLINE_MODE_ON;
} else if (matches(*argv, "delta") == 0) {
NEXT_ARG();
if (opt.delta) {
fprintf(stderr, "etf: duplicate \"delta\" specification\n");
return -1;
}
if (get_s32(&opt.delta, *argv, 0)) {
explain1("delta", *argv);
return -1;
}
} else if (matches(*argv, "clockid") == 0) {
NEXT_ARG();
if (opt.clockid != CLOCKID_INVALID) {
fprintf(stderr, "etf: duplicate \"clockid\" specification\n");
return -1;
}
if (get_clockid(&opt.clockid, *argv)) {
explain_clockid(*argv);
return -1;
}
} else if (strcmp(*argv, "help") == 0) {
explain();
return -1;
} else {
fprintf(stderr, "etf: unknown parameter \"%s\"\n", *argv);
explain();
return -1;
}
argc--; argv++;
}
tail = NLMSG_TAIL(n);
addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
addattr_l(n, 2024, TCA_ETF_PARMS, &opt, sizeof(opt));
tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
return 0;
}
static int etf_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
{
struct rtattr *tb[TCA_ETF_MAX+1];
struct tc_etf_qopt *qopt;
if (opt == NULL)
return 0;
parse_rtattr_nested(tb, TCA_ETF_MAX, opt);
if (tb[TCA_ETF_PARMS] == NULL)
return -1;
qopt = RTA_DATA(tb[TCA_ETF_PARMS]);
if (RTA_PAYLOAD(tb[TCA_ETF_PARMS]) < sizeof(*qopt))
return -1;
print_string(PRINT_ANY, "clockid", "clockid %s ",
get_clock_name(qopt->clockid));
print_uint(PRINT_ANY, "delta", "delta %d ", qopt->delta);
print_string(PRINT_ANY, "offload", "offload %s ",
(qopt->flags & TC_ETF_OFFLOAD_ON) ? "on" : "off");
print_string(PRINT_ANY, "deadline_mode", "deadline_mode %s",
(qopt->flags & TC_ETF_DEADLINE_MODE_ON) ? "on" : "off");
return 0;
}
struct qdisc_util etf_qdisc_util = {
.id = "etf",
.parse_qopt = etf_parse_opt,
.print_qopt = etf_print_opt,
};