[RFC iproute2 1/2] update headers with CBS API [RFC]

[RFC iproute2 1/2] update headers with CBS API [RFC]

[Vinicius Costa Gomes]

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
---
 include/linux/pkt_sched.h | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/include/linux/pkt_sched.h b/include/linux/pkt_sched.h
index 099bf552..ba6c9a54 100644
--- a/include/linux/pkt_sched.h
+++ b/include/linux/pkt_sched.h
@@ -871,4 +871,33 @@ struct tc_pie_xstats {
 	__u32 maxq;             /* maximum queue size */
 	__u32 ecn_mark;         /* packets marked with ecn*/
 };
+
+/* CBS */
+/* FIXME: this is only for usage with ndo_setup_tc(), this should be
+ * in another header someplace else. Is pkt_cls.h the right place?
+ */
+struct tc_cbs_qopt_offload {
+	__u8		enable;
+	__s32		queue;
+	__s32		hicredit;
+	__s32		locredit;
+	__s32		idleslope;
+	__s32		sendslope;
+};
+
+struct tc_cbs_qopt {
+	__s32		hicredit;
+	__s32		locredit;
+	__s32		idleslope;
+	__s32		sendslope;
+};
+
+enum {
+	TCA_CBS_UNSPEC,
+	TCA_CBS_PARMS,
+	__TCA_CBS_MAX,
+};
+
+#define TCA_CBS_MAX (__TCA_CBS_MAX - 1)
+
 #endif
-- 
2.14.1

[RFC iproute2 2/2] tc: Add support for the CBS qdisc

[Vinicius Costa Gomes]

The Credit Based Shaper (CBS) queueing discipline allows bandwidth
reservation with sub-milisecond precision. It is defined by the
802.1Q-2014 specification (section 8.6.8.2 and Annex L).

The syntax is:

tc qdisc add dev DEV parent NODE cbs locredit <LOCREDIT> hicredit
<HICREDIT> sendslope <SENDSLOPE> idleslope <IDLESLOPE>

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
---
 tc/Makefile |   1 +
 tc/q_cbs.c  | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 135 insertions(+)
 create mode 100644 tc/q_cbs.c

diff --git a/tc/Makefile b/tc/Makefile
index a9b4b8e6..f0091217 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -73,6 +73,7 @@ TCMODULES += q_hhf.o
 TCMODULES += q_clsact.o
 TCMODULES += e_bpf.o
 TCMODULES += f_matchall.o
+TCMODULES += q_cbs.o
 
 TCSO :=
 ifeq ($(TC_CONFIG_ATM),y)
diff --git a/tc/q_cbs.c b/tc/q_cbs.c
new file mode 100644
index 00000000..0120e838
--- /dev/null
+++ b/tc/q_cbs.c
@@ -0,0 +1,134 @@
+/*
+ * q_tbf.c		TBF.
+ *
+ *		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:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#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 "utils.h"
+#include "tc_util.h"
+
+static void explain(void)
+{
+	fprintf(stderr, "Usage: ... tbf hicredit BYTES locredit BYTES sendslope BPS idleslope BPS\n");
+}
+
+static void explain1(const char *arg, const char *val)
+{
+	fprintf(stderr, "cbs: illegal value for \"%s\": \"%s\"\n", arg, val);
+}
+
+static int cbs_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
+{
+	int ok = 0;
+	struct tc_cbs_qopt opt = {};
+	struct rtattr *tail;
+
+	while (argc > 0) {
+		if (matches(*argv, "hicredit") == 0) {
+			NEXT_ARG();
+			if (opt.hicredit) {
+				fprintf(stderr, "cbs: duplicate \"hicredit\" specification\n");
+				return -1;
+			}
+			if (get_s32(&opt.hicredit, *argv, 0)) {
+				explain1("hicredit", *argv);
+				return -1;
+			}
+			ok++;
+		} else if (matches(*argv, "locredit") == 0) {
+			NEXT_ARG();
+			if (opt.locredit) {
+				fprintf(stderr, "cbs: duplicate \"locredit\" specification\n");
+				return -1;
+			}
+			if (get_s32(&opt.locredit, *argv, 0)) {
+				explain1("locredit", *argv);
+				return -1;
+			}
+			ok++;
+		} else if (matches(*argv, "sendslope") == 0) {
+			NEXT_ARG();
+			if (opt.sendslope) {
+				fprintf(stderr, "cbs: duplicate \"sendslope\" specification\n");
+				return -1;
+			}
+			if (get_s32(&opt.sendslope, *argv, 0)) {
+				explain1("sendslope", *argv);
+				return -1;
+			}
+			ok++;
+		} else if (matches(*argv, "idleslope") == 0) {
+			NEXT_ARG();
+			if (opt.idleslope) {
+				fprintf(stderr, "cbs: duplicate \"idleslope\" specification\n");
+				return -1;
+			}
+			if (get_s32(&opt.idleslope, *argv, 0)) {
+				explain1("idleslope", *argv);
+				return -1;
+			}
+			ok++;
+		} else if (strcmp(*argv, "help") == 0) {
+			explain();
+			return -1;
+		} else {
+			fprintf(stderr, "cbs: 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_CBS_PARMS, &opt, sizeof(opt));
+	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
+	return 0;
+}
+
+static int cbs_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
+{
+	struct rtattr *tb[TCA_TBF_MAX+1];
+	struct tc_cbs_qopt *qopt;
+
+	if (opt == NULL)
+		return 0;
+
+	parse_rtattr_nested(tb, TCA_CBS_MAX, opt);
+
+	if (tb[TCA_CBS_PARMS] == NULL)
+		return -1;
+
+	qopt = RTA_DATA(tb[TCA_CBS_PARMS]);
+	if (RTA_PAYLOAD(tb[TCA_CBS_PARMS])  < sizeof(*qopt))
+		return -1;
+
+	fprintf(f, "hicredit %d ", qopt->hicredit);
+	fprintf(f, "locredit %d ", qopt->locredit);
+	fprintf(f, "sendslope %d ", qopt->sendslope);
+	fprintf(f, "idleslope %d ", qopt->idleslope);
+
+	return 0;
+}
+
+struct qdisc_util cbs_qdisc_util = {
+	.id		= "cbs",
+	.parse_qopt	= cbs_parse_opt,
+	.print_qopt	= cbs_print_opt,
+};
-- 
2.14.1