From: Vinicius Costa Gomes <vinicius.go...@intel.com>
The Time Based Scheduler (TBS) queueing discipline allows precise
control of the transmission time of packets.
The syntax is:
tc qdisc add dev DEV parent NODE tbs delta <DELTA>
clockid <CLOCKID> [offload] [sorting]
Signed-off-by: Vinicius Costa Gomes <vinicius.go...@intel.com>
Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palen...@intel.com>
---
tc/Makefile | 1 +
tc/q_tbs.c | 200 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 201 insertions(+)
create mode 100644 tc/q_tbs.c
diff --git a/tc/Makefile b/tc/Makefile
index 3716dd6a..3c87b0dc 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -71,6 +71,7 @@ TCMODULES += q_clsact.o
TCMODULES += e_bpf.o
TCMODULES += f_matchall.o
TCMODULES += q_cbs.o
+TCMODULES += q_tbs.o
TCSO :=
ifeq ($(TC_CONFIG_ATM),y)
diff --git a/tc/q_tbs.c b/tc/q_tbs.c
new file mode 100644
index 00000000..b0823dc9
--- /dev/null
+++ b/tc/q_tbs.c
@@ -0,0 +1,200 @@
+/*
+ * q_tbs.c TBS.
+ *
+ * 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.go...@intel.com>
+ * Jesus Sanchez-Palencia <jesus.sanchez-palen...@intel.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <linux/ptp_clock.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include "utils.h"
+#include "tc_util.h"
+
+/* clockid is invalid if bits 0, 1, 2 are set as described by posix-timers.h */
+#define CLOCKID_INVALID (BIT(0) | BIT(1) | BIT(2))
+#define PTP_MAX_DEV_PATH 16
+
+/* fd to clockid helpers. Copied from posix-timers.h. */
+#define CLOCKFD 3
+static inline clockid_t make_process_cpuclock(const unsigned int pid,
+ const clockid_t clock)
+{
+ return ((~pid) << 3) | clock;
+}
+
+static inline clockid_t fd_to_clockid(const int fd)
+{
+ return make_process_cpuclock((unsigned int) fd, CLOCKFD);
+}
+
+static void explain(void)
+{
+ fprintf(stderr, "Usage: ... tbs delta NANOS clockid CLOCKID [offload]
[sorting]\n");
+ fprintf(stderr, "CLOCKID must be a valid SYS-V id (i.e. CLOCK_TAI) or \
+ a dynamic clock (i.e. /dev/ptp0).\n");
+}
+
+static void explain1(const char *arg, const char *val)
+{
+ fprintf(stderr, "tbs: illegal value for \"%s\": \"%s\"\n", arg, val);
+}
+
+static void explain_clockid(const char *val)
+{
+ fprintf(stderr, "tbs: illegal value for \"clockid\": \"%s\".\n", val);
+ fprintf(stderr, "It must be a valid SYS-V id (i.e. CLOCK_TAI) or "\
+ "dynamic clock (i.e. /dev/ptp0).\n");
+}
+
+static int get_clockid(__s32 *val, const char *arg)
+{
+ const struct static_clockid {
+ const char *name;
+ clockid_t clockid;
+ } clockids_sysv[] = {
+ { "CLOCK_REALTIME", CLOCK_REALTIME },
+ { "CLOCK_TAI", CLOCK_TAI },
+ { "CLOCK_BOOTTIME", CLOCK_BOOTTIME },
+ { "CLOCK_MONOTONIC", CLOCK_MONOTONIC },
+ { NULL }
+ };
+
+ struct ptp_clock_caps capabilities;
+ char ptp_path[PTP_MAX_DEV_PATH];
+ const struct static_clockid *c;
+ int fd_ptp;
+
+ for (c = clockids_sysv; c->name; c++) {
+ if (strncasecmp(c->name, arg, 25) == 0) {
+ *val = c->clockid;
+
+ return 0;
+ }
+ }
+
+ snprintf(ptp_path, sizeof(ptp_path), "%s", arg);
+ fd_ptp = open(ptp_path, O_RDONLY);
+
+ /* Make sure the path provided points to a PTP chardev. */
+ if (fd_ptp < 0 || ioctl(fd_ptp, PTP_CLOCK_GETCAPS, &capabilities) < 0) {
+ return -1;
+ }
+
+ *val = fd_to_clockid(fd_ptp);
+ return 0;
+}
+
+
+static int tbs_parse_opt(struct qdisc_util *qu, int argc,
+ char **argv, struct nlmsghdr *n, const char *dev)
+{
+ struct tc_tbs_qopt opt = {
+ .clockid = CLOCKID_INVALID,
+ };
+ struct rtattr *tail;
+
+ while (argc > 0) {
+ if (matches(*argv, "offload") == 0) {
+ if (opt.flags & TC_TBS_OFFLOAD_ON) {
+ fprintf(stderr, "tbs: duplicate \"offload\"
specification\n");
+ return -1;
+ }
+
+ opt.flags |= TC_TBS_OFFLOAD_ON;
+ } else if (matches(*argv, "sorting") == 0) {
+ if (opt.flags & TC_TBS_SORTING_ON) {
+ fprintf(stderr, "tbs: duplicate \"sorting\"
specification\n");
+ return -1;
+ }
+
+ opt.flags |= TC_TBS_SORTING_ON;
+ } else if (matches(*argv, "delta") == 0) {
+ NEXT_ARG();
+ if (opt.delta) {
+ fprintf(stderr, "tbs: 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, "tbs: 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, "tbs: 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_TBS_PARMS, &opt, sizeof(opt));
+ tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
+ return 0;
+}
+
+static int tbs_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
+{
+ struct rtattr *tb[TCA_TBS_MAX+1];
+ struct tc_tbs_qopt *qopt;
+
+ if (opt == NULL)
+ return 0;
+
+ parse_rtattr_nested(tb, TCA_TBS_MAX, opt);
+
+ if (tb[TCA_TBS_PARMS] == NULL)
+ return -1;
+
+ qopt = RTA_DATA(tb[TCA_TBS_PARMS]);
+ if (RTA_PAYLOAD(tb[TCA_TBS_PARMS]) < sizeof(*qopt))
+ return -1;
+
+ fprintf(f, "clockid ");
+ if (qopt->clockid == CLOCKID_INVALID)
+ fprintf(f, "invalid ");
+ else
+ fprintf(f, "%d ", qopt->clockid);
+
+ fprintf(f, "delta %d ", qopt->delta);
+ fprintf(f, "offload %s ", (qopt->flags & TC_TBS_OFFLOAD_ON) ?
+ "on" : "off");
+ fprintf(f, "sorting %s", (qopt->flags & TC_TBS_SORTING_ON) ?
+ "on" : "off");
+
+ return 0;
+}
+
+struct qdisc_util tbs_qdisc_util = {
+ .id = "tbs",
+ .parse_qopt = tbs_parse_opt,
+ .print_qopt = tbs_print_opt,
+};
--
2.16.2
