[PATCH iproute2 net-next v1 0/6] introduce the taprio scheduler

[PATCH iproute2 net-next v1 0/6] introduce the taprio scheduler

[Vinicius Costa Gomes]

Hi,

Changes from RFC:
  - Removed support for the sched-file parameter, in favor of
    supporting the batch mode feature;

This is the iproute2 side of the taprio v1 series.

Please see the kernel side cover letter for more information about how
to test this.

Cheers,

[PATCH iproute2 net-next v1 1/6] utils: Implement get_s64()

[Vinicius Costa Gomes]

Add this helper to read signed 64-bit integers from a string.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
---
 include/utils.h |  1 +
 lib/utils.c     | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/include/utils.h b/include/utils.h
index 8cb4349e..58574a05 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -139,6 +139,7 @@ int get_time_rtt(unsigned *val, const char *arg, int *raw);
 #define get_byte get_u8
 #define get_ushort get_u16
 #define get_short get_s16
+int get_s64(__s64 *val, const char *arg, int base);
 int get_u64(__u64 *val, const char *arg, int base);
 int get_u32(__u32 *val, const char *arg, int base);
 int get_s32(__s32 *val, const char *arg, int base);
diff --git a/lib/utils.c b/lib/utils.c
index e87ecf31..1b84b801 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -383,6 +383,27 @@ int get_u8(__u8 *val, const char *arg, int base)
 	return 0;
 }
 
+int get_s64(__s64 *val, const char *arg, int base)
+{
+	long res;
+	char *ptr;
+
+	errno = 0;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtoll(arg, &ptr, base);
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+	if ((res == LLONG_MIN || res == LLONG_MAX) && errno == ERANGE)
+		return -1;
+	if (res > INT64_MAX || res < INT64_MIN)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
 int get_s32(__s32 *val, const char *arg, int base)
 {
 	long res;
-- 
2.19.0

[PATCH iproute2 net-next v1 2/6] include: Add helper to retrieve a __s64 from a netlink msg

[Vinicius Costa Gomes]

This allows signed 64-bit integers to be retrieved from a netlink
message.
---
 include/libnetlink.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/libnetlink.h b/include/libnetlink.h
index 9d9249e6..88164975 100644
--- a/include/libnetlink.h
+++ b/include/libnetlink.h
@@ -185,6 +185,13 @@ static inline __u64 rta_getattr_u64(const struct rtattr *rta)
 	memcpy(&tmp, RTA_DATA(rta), sizeof(__u64));
 	return tmp;
 }
+static inline __s64 rta_getattr_s64(const struct rtattr *rta)
+{
+	__s64 tmp;
+
+	memcpy(&tmp, RTA_DATA(rta), sizeof(__s64));
+	return tmp;
+}
 static inline const char *rta_getattr_str(const struct rtattr *rta)
 {
 	return (const char *)RTA_DATA(rta);
-- 
2.19.0

[PATCH iproute2 net-next v1 3/6] libnetlink: Add helper for getting a __s32 from netlink msgs

[Vinicius Costa Gomes]

From: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>

This function retrieves a signed 32-bit integer from a netlink message
and returns it.

Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
---
 include/libnetlink.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/libnetlink.h b/include/libnetlink.h
index 88164975..79ba793e 100644
--- a/include/libnetlink.h
+++ b/include/libnetlink.h
@@ -185,6 +185,10 @@ static inline __u64 rta_getattr_u64(const struct rtattr *rta)
 	memcpy(&tmp, RTA_DATA(rta), sizeof(__u64));
 	return tmp;
 }
+static inline __s32 rta_getattr_s32(const struct rtattr *rta)
+{
+	return *(__s32 *)RTA_DATA(rta);
+}
 static inline __s64 rta_getattr_s64(const struct rtattr *rta)
 {
 	__s64 tmp;
-- 
2.19.0

[PATCH iproute2 net-next v1 4/6] include: add definitions for taprio [DO NOT COMMIT]

[Vinicius Costa Gomes]

DO NOT COMMIT

This patch exists only to ease the testing, until this header is
updated with the definitions from the kernel.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
---
 include/uapi/linux/pkt_sched.h | 52 ++++++++++++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 3 deletions(-)

diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h
index 8975fd1a..89ee47c2 100644
--- a/include/uapi/linux/pkt_sched.h
+++ b/include/uapi/linux/pkt_sched.h
@@ -395,9 +395,9 @@ enum {
 struct tc_htb_xstats {
 	__u32 lends;
 	__u32 borrows;
-	__u32 giants;	/* too big packets (rate will not be accurate) */
-	__u32 tokens;
-	__u32 ctokens;
+	__u32 giants;	/* unused since 'Make HTB scheduler work with TSO.' */
+	__s32 tokens;
+	__s32 ctokens;
 };
 
 /* HFSC section */
@@ -1084,4 +1084,50 @@ enum {
 	CAKE_ATM_MAX
 };
 
+
+/* TAPRIO */
+enum {
+	TC_TAPRIO_CMD_SET_GATES = 0x00,
+	TC_TAPRIO_CMD_SET_AND_HOLD = 0x01,
+	TC_TAPRIO_CMD_SET_AND_RELEASE = 0x02,
+};
+
+enum {
+	TCA_TAPRIO_SCHED_ENTRY_UNSPEC,
+	TCA_TAPRIO_SCHED_ENTRY_INDEX, /* u32 */
+	TCA_TAPRIO_SCHED_ENTRY_CMD, /* u8 */
+	TCA_TAPRIO_SCHED_ENTRY_GATE_MASK, /* u32 */
+	TCA_TAPRIO_SCHED_ENTRY_INTERVAL, /* u32 */
+	__TCA_TAPRIO_SCHED_ENTRY_MAX,
+};
+#define TCA_TAPRIO_SCHED_ENTRY_MAX (__TCA_TAPRIO_SCHED_ENTRY_MAX - 1)
+
+/* The format for schedule entry list is:
+ * [TCA_TAPRIO_SCHED_ENTRY_LIST]
+ *   [TCA_TAPRIO_SCHED_ENTRY]
+ *     [TCA_TAPRIO_SCHED_ENTRY_CMD]
+ *     [TCA_TAPRIO_SCHED_ENTRY_GATES]
+ *     [TCA_TAPRIO_SCHED_ENTRY_INTERVAL]
+ */
+enum {
+	TCA_TAPRIO_SCHED_UNSPEC,
+	TCA_TAPRIO_SCHED_ENTRY,
+	__TCA_TAPRIO_SCHED_MAX,
+};
+
+#define TCA_TAPRIO_SCHED_MAX (__TCA_TAPRIO_SCHED_MAX - 1)
+
+enum {
+	TCA_TAPRIO_ATTR_UNSPEC,
+	TCA_TAPRIO_ATTR_PRIOMAP, /* struct tc_mqprio_qopt */
+	TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST, /* nested of entry */
+	TCA_TAPRIO_ATTR_SCHED_BASE_TIME, /* s64 */
+	TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY, /* single entry */
+	TCA_TAPRIO_ATTR_SCHED_CLOCKID, /* s32 */
+	TCA_TAPRIO_PAD,
+	__TCA_TAPRIO_ATTR_MAX,
+};
+
+#define TCA_TAPRIO_ATTR_MAX (__TCA_TAPRIO_ATTR_MAX - 1)
+
 #endif
-- 
2.19.0

[PATCH iproute2 net-next v1 5/6] tc: Add support for configuring the taprio scheduler

[Vinicius Costa Gomes]

This traffic scheduler allows traffic classes states (transmission
allowed/not allowed, in the simplest case) to be scheduled, according
to a pre-generated time sequence. This is the basis of the IEEE
802.1Qbv specification.

Example configuration:

tc qdisc replace dev enp3s0 parent root handle 100 taprio \
          num_tc 3 \
	  map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \
	  queues 1@0 1@1 2@2 \
	  base-time 1528743495910289987 \
	  sched-entry S 01 300000 \
	  sched-entry S 02 300000 \
	  sched-entry S 04 300000 \
	  clockid CLOCK_TAI

The configuration format is similar to mqprio. The main difference is
the presence of a schedule, built by multiple "sched-entry"
definitions, each entry has the following format:

     sched-entry <CMD> <GATE MASK> <INTERVAL>

The only supported <CMD> is "S", which means "SetGateStates",
following the IEEE 802.1Qbv-2015 definition (Table 8-6). <GATE MASK>
is a bitmask where each bit is a associated with a traffic class, so
bit 0 (the least significant bit) being "on" means that traffic class
0 is "active" for that schedule entry. <INTERVAL> is a time duration
in nanoseconds that specifies for how long that state defined by <CMD>
and <GATE MASK> should be held before moving to the next entry.

This schedule is circular, that is, after the last entry is executed
it starts from the first one, indefinitely.

The other parameters can be defined as follows:

 - base-time: specifies the instant when the schedule starts, if
  'base-time' is a time in the past, the schedule will start at

 	      base-time + (N * cycle-time)

   where N is the smallest integer so the resulting time is greater
   than "now", and "cycle-time" is the sum of all the intervals of the
   entries in the schedule;

 - clockid: specifies the reference clock to be used;

The parameters should be similar to what the IEEE 802.1Q family of
specification defines.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
---
 tc/Makefile   |   1 +
 tc/q_taprio.c | 410 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 411 insertions(+)
 create mode 100644 tc/q_taprio.c

diff --git a/tc/Makefile b/tc/Makefile
index 5a1a7ff9..25a28284 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -74,6 +74,7 @@ TCMODULES += e_bpf.o
 TCMODULES += f_matchall.o
 TCMODULES += q_cbs.o
 TCMODULES += q_etf.o
+TCMODULES += q_taprio.o
 
 TCSO :=
 ifeq ($(TC_CONFIG_ATM),y)
diff --git a/tc/q_taprio.c b/tc/q_taprio.c
new file mode 100644
index 00000000..645a7613
--- /dev/null
+++ b/tc/q_taprio.c
@@ -0,0 +1,410 @@
+/*
+ * q_taprio.c	Time Aware Priority Scheduler
+ *
+ *		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 <syslog.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include "utils.h"
+#include "tc_util.h"
+#include "list.h"
+
+struct sched_entry {
+	struct list_head list;
+	uint32_t index;
+	uint32_t interval;
+	uint32_t gatemask;
+	uint8_t cmd;
+};
+
+#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: ... taprio clockid CLOCKID\n");
+	fprintf(stderr, "                  [num_tc NUMBER] [map P0 P1 ...] ");
+	fprintf(stderr, "                  [queues COUNT@OFFSET COUNT@OFFSET COUNT@OFFSET ...] ");
+	fprintf(stderr, "                  [ [sched-entry index cmd gate-mask interval] ... ] ");
+	fprintf(stderr, "                  [base-time time] ");
+	fprintf(stderr, "\nCLOCKID must be a valid SYS-V id (i.e. CLOCK_TAI)");
+	fprintf(stderr, "\n");
+}
+
+static void explain_clockid(const char *val)
+{
+	fprintf(stderr, "taprio: 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 str_to_entry_cmd(const char *str)
+{
+	if (strcmp(str, "S") == 0)
+		return TC_TAPRIO_CMD_SET_GATES;
+
+	if (strcmp(str, "H") == 0)
+		return TC_TAPRIO_CMD_SET_AND_HOLD;
+
+	if (strcmp(str, "R") == 0)
+		return TC_TAPRIO_CMD_SET_AND_RELEASE;
+
+	return -1;
+}
+
+static int add_sched_list(struct list_head *sched_entries, struct nlmsghdr *n)
+{
+	struct sched_entry *e;
+
+	list_for_each_entry(e, sched_entries, list) {
+		struct rtattr *a;
+
+		a = addattr_nest(n, 1024, TCA_TAPRIO_SCHED_ENTRY);
+
+		addattr_l(n, 1024, TCA_TAPRIO_SCHED_ENTRY_CMD, &e->cmd, sizeof(e->cmd));
+		addattr_l(n, 1024, TCA_TAPRIO_SCHED_ENTRY_GATE_MASK, &e->gatemask, sizeof(e->gatemask));
+		addattr_l(n, 1024, TCA_TAPRIO_SCHED_ENTRY_INTERVAL, &e->interval, sizeof(e->interval));
+
+		addattr_nest_end(n, a);
+	}
+
+	return 0;
+}
+
+static void explain_sched_entry(void)
+{
+	fprintf(stderr, "Usage: ... taprio ... sched-entry <cmd> <gate mask> <interval>\n");
+}
+
+static struct sched_entry *create_entry(uint32_t gatemask, uint32_t interval, uint8_t cmd)
+{
+	struct sched_entry *e;
+
+	e = calloc(1, sizeof(*e));
+	if (!e)
+		return NULL;
+
+	e->gatemask = gatemask;
+	e->interval = interval;
+	e->cmd = cmd;
+
+	return e;
+}
+
+static int taprio_parse_opt(struct qdisc_util *qu, int argc,
+			    char **argv, struct nlmsghdr *n, const char *dev)
+{
+	__s32 clockid = CLOCKID_INVALID;
+	struct tc_mqprio_qopt opt = { };
+	struct list_head sched_entries;
+	struct rtattr *tail;
+	__s64 base_time = 0;
+	int err, idx;
+
+	INIT_LIST_HEAD(&sched_entries);
+
+	while (argc > 0) {
+		idx = 0;
+		if (strcmp(*argv, "num_tc") == 0) {
+			NEXT_ARG();
+			if (get_u8(&opt.num_tc, *argv, 10)) {
+				fprintf(stderr, "Illegal \"num_tc\"\n");
+				return -1;
+			}
+		} else if (strcmp(*argv, "map") == 0) {
+			while (idx < TC_QOPT_MAX_QUEUE && NEXT_ARG_OK()) {
+				NEXT_ARG();
+				if (get_u8(&opt.prio_tc_map[idx], *argv, 10)) {
+					PREV_ARG();
+					break;
+				}
+				idx++;
+			}
+			for ( ; idx < TC_QOPT_MAX_QUEUE; idx++)
+				opt.prio_tc_map[idx] = 0;
+		} else if (strcmp(*argv, "queues") == 0) {
+			char *tmp, *tok;
+
+			while (idx < TC_QOPT_MAX_QUEUE && NEXT_ARG_OK()) {
+				NEXT_ARG();
+
+				tmp = strdup(*argv);
+				if (!tmp)
+					break;
+
+				tok = strtok(tmp, "@");
+				if (get_u16(&opt.count[idx], tok, 10)) {
+					free(tmp);
+					PREV_ARG();
+					break;
+				}
+				tok = strtok(NULL, "@");
+				if (get_u16(&opt.offset[idx], tok, 10)) {
+					free(tmp);
+					PREV_ARG();
+					break;
+				}
+				free(tmp);
+				idx++;
+			}
+		} else if (strcmp(*argv, "sched-entry") == 0) {
+			uint32_t mask, interval;
+			struct sched_entry *e;
+			uint8_t cmd;
+
+			NEXT_ARG();
+			err = str_to_entry_cmd(*argv);
+			if (err < 0) {
+				explain_sched_entry();
+				return  -1;
+			}
+			cmd = err;
+
+			NEXT_ARG();
+			if (get_u32(&mask, *argv, 16)) {
+				explain_sched_entry();
+				return -1;
+			}
+
+			NEXT_ARG();
+			if (get_u32(&interval, *argv, 0)) {
+				explain_sched_entry();
+				return -1;
+			}
+
+			e = create_entry(mask, interval, cmd);
+			if (!e) {
+				fprintf(stderr, "taprio: not enough memory for new schedule entry\n");
+				return -1;
+			}
+
+			list_add_tail(&e->list, &sched_entries);
+
+		} else if (strcmp(*argv, "base-time") == 0) {
+			NEXT_ARG();
+			if (get_s64(&base_time, *argv, 10)) {
+				PREV_ARG();
+				break;
+			}
+		} else if (strcmp(*argv, "clockid") == 0) {
+			NEXT_ARG();
+			if (clockid != CLOCKID_INVALID) {
+				fprintf(stderr, "taprio: duplicate \"clockid\" specification\n");
+				return -1;
+			}
+			if (get_clockid(&clockid, *argv)) {
+				explain_clockid(*argv);
+				return -1;
+			}
+		} else if (strcmp(*argv, "help") == 0) {
+			explain();
+			return -1;
+		} else {
+			fprintf(stderr, "Unknown argument\n");
+			return -1;
+		}
+		argc--; argv++;
+	}
+
+	tail = NLMSG_TAIL(n);
+	addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
+
+	if (opt.num_tc > 0)
+		addattr_l(n, 1024, TCA_TAPRIO_ATTR_PRIOMAP, &opt, sizeof(opt));
+
+	if (base_time)
+		addattr_l(n, 1024, TCA_TAPRIO_ATTR_SCHED_BASE_TIME, &base_time, sizeof(base_time));
+
+	addattr_l(n, 1024, TCA_TAPRIO_ATTR_SCHED_CLOCKID, &clockid, sizeof(clockid));
+
+	if (!list_empty(&sched_entries)) {
+		struct rtattr *entry_list;
+		entry_list = addattr_nest(n, 1024, TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST | NLA_F_NESTED);
+
+		err = add_sched_list(&sched_entries, n);
+		if (err < 0) {
+			fprintf(stderr, "Could not add schedule to netlink message\n");
+			return -1;
+		}
+
+		addattr_nest_end(n, entry_list);
+	}
+
+	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
+
+	return 0;
+}
+
+static const char *command_to_str(__u8 cmd)
+{
+	switch (cmd) {
+	case TC_TAPRIO_CMD_SET_GATES:
+		return "S";
+	case TC_TAPRIO_CMD_SET_AND_HOLD:
+		return "H";
+	case TC_TAPRIO_CMD_SET_AND_RELEASE:
+		return "R";
+	default:
+		return "Invalid";
+	}
+}
+
+static int print_sched_list(FILE *f, struct rtattr *list)
+{
+	struct rtattr *item;
+	int rem;
+
+	if (list == NULL)
+		return 0;
+
+	rem = RTA_PAYLOAD(list);
+
+	open_json_array(PRINT_JSON, "schedule");
+
+	for (item = RTA_DATA(list); RTA_OK(item, rem); item = RTA_NEXT(item, rem)) {
+		struct rtattr *tb[TCA_TAPRIO_SCHED_ENTRY_MAX + 1];
+		__u32 index = 0, gatemask = 0, interval = 0;
+		__u8 command = 0;
+
+		parse_rtattr_nested(tb, TCA_TAPRIO_SCHED_ENTRY_MAX, item);
+
+		if (tb[TCA_TAPRIO_SCHED_ENTRY_INDEX])
+			index = rta_getattr_u32(tb[TCA_TAPRIO_SCHED_ENTRY_INDEX]);
+
+		if (tb[TCA_TAPRIO_SCHED_ENTRY_CMD])
+			command = rta_getattr_u8(tb[TCA_TAPRIO_SCHED_ENTRY_CMD]);
+
+		if (tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK])
+			gatemask = rta_getattr_u32(tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK]);
+
+		if (tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL])
+			interval = rta_getattr_u32(tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL]);
+
+		open_json_object(NULL);
+		print_uint(PRINT_ANY, "index", "\tindex %u", index);
+		print_string(PRINT_ANY, "cmd", " cmd %s", command_to_str(command));
+		print_0xhex(PRINT_ANY, "gatemask", " gatemask %#x", gatemask);
+		print_uint(PRINT_ANY, "interval", " interval %u", interval);
+		close_json_object();
+
+		print_string(PRINT_FP, NULL, "%s", _SL_);
+	}
+
+	close_json_array(PRINT_ANY, "");
+
+	return 0;
+}
+
+static int taprio_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
+{
+	struct rtattr *tb[TCA_TAPRIO_ATTR_MAX + 1];
+	struct tc_mqprio_qopt *qopt = 0;
+	__s32 clockid = CLOCKID_INVALID;
+	__s64 base_time = 0;
+	int i;
+
+	if (opt == NULL)
+		return 0;
+
+	parse_rtattr_nested(tb, TCA_TAPRIO_ATTR_MAX, opt);
+
+	if (tb[TCA_TAPRIO_ATTR_PRIOMAP] == NULL)
+		return -1;
+
+	qopt = RTA_DATA(tb[TCA_TAPRIO_ATTR_PRIOMAP]);
+
+	print_uint(PRINT_ANY, "tc", "tc %u ", qopt->num_tc);
+
+	open_json_array(PRINT_ANY, "map");
+	for (i = 0; i <= TC_PRIO_MAX; i++)
+		print_uint(PRINT_ANY, NULL, " %u", qopt->prio_tc_map[i]);
+	close_json_array(PRINT_ANY, "");
+
+	print_string(PRINT_FP, NULL, "%s", _SL_);
+
+	open_json_array(PRINT_ANY, "queues");
+	for (i = 0; i < qopt->num_tc; i++) {
+		open_json_object(NULL);
+		print_uint(PRINT_ANY, "offset", " offset %u", qopt->offset[i]);
+		print_uint(PRINT_ANY, "count", " count %u", qopt->count[i]);
+		close_json_object();
+	}
+	close_json_array(PRINT_ANY, "");
+
+	print_string(PRINT_FP, NULL, "%s", _SL_);
+
+	if (tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME])
+		base_time = rta_getattr_s64(tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]);
+
+	if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID])
+		clockid = rta_getattr_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]);
+
+	print_string(PRINT_ANY, "clockid", "clockid %s", get_clock_name(clockid));
+
+	print_lluint(PRINT_ANY, "base_time", " base-time %lld", base_time);
+
+	print_string(PRINT_FP, NULL, "%s", _SL_);
+
+	return print_sched_list(f, tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST]);
+}
+
+struct qdisc_util taprio_qdisc_util = {
+	.id		= "taprio",
+	.parse_qopt	= taprio_parse_opt,
+	.print_qopt	= taprio_print_opt,
+};
-- 
2.19.0

Re: [PATCH iproute2 net-next v1 5/6] tc: Add support for configuring the taprio scheduler

[David Ahern]

On 9/28/18 7:10 PM, Vinicius Costa Gomes wrote:
> This traffic scheduler allows traffic classes states (transmission
> allowed/not allowed, in the simplest case) to be scheduled, according
> to a pre-generated time sequence. This is the basis of the IEEE
> 802.1Qbv specification.
> 
> Example configuration:
> 
> tc qdisc replace dev enp3s0 parent root handle 100 taprio \
>           num_tc 3 \
> 	  map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \
> 	  queues 1@0 1@1 2@2 \
> 	  base-time 1528743495910289987 \
> 	  sched-entry S 01 300000 \
> 	  sched-entry S 02 300000 \
> 	  sched-entry S 04 300000 \
> 	  clockid CLOCK_TAI
> 
> The configuration format is similar to mqprio. The main difference is
> the presence of a schedule, built by multiple "sched-entry"
> definitions, each entry has the following format:
> 
>      sched-entry <CMD> <GATE MASK> <INTERVAL>
> 
> The only supported <CMD> is "S", which means "SetGateStates",

...

> +static int str_to_entry_cmd(const char *str)
> +{
> +	if (strcmp(str, "S") == 0)
> +		return TC_TAPRIO_CMD_SET_GATES;
> +
> +	if (strcmp(str, "H") == 0)
> +		return TC_TAPRIO_CMD_SET_AND_HOLD;
> +
> +	if (strcmp(str, "R") == 0)
> +		return TC_TAPRIO_CMD_SET_AND_RELEASE;

If 'S' is the only supported command, what are 'H' and 'R'?

> +
> +	return -1;
> +}
> +

> +
> +static const char *command_to_str(__u8 cmd)
> +{
> +	switch (cmd) {
> +	case TC_TAPRIO_CMD_SET_GATES:
> +		return "S";
> +	case TC_TAPRIO_CMD_SET_AND_HOLD:
> +		return "H";
> +	case TC_TAPRIO_CMD_SET_AND_RELEASE:
> +		return "R";
> +	default:
> +		return "Invalid";
> +	}
> +}

And can you keep str-to-command and command-to-str helpers close
together in the code.

Re: [PATCH iproute2 net-next v1 5/6] tc: Add support for configuring the taprio scheduler

[Vinicius Costa Gomes]

Hi David,

David Ahern <dsahern@gmail.com> writes:

> On 9/28/18 7:10 PM, Vinicius Costa Gomes wrote:
>> This traffic scheduler allows traffic classes states (transmission
>> allowed/not allowed, in the simplest case) to be scheduled, according
>> to a pre-generated time sequence. This is the basis of the IEEE
>> 802.1Qbv specification.
>> 
>> Example configuration:
>> 
>> tc qdisc replace dev enp3s0 parent root handle 100 taprio \
>>           num_tc 3 \
>> 	  map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \
>> 	  queues 1@0 1@1 2@2 \
>> 	  base-time 1528743495910289987 \
>> 	  sched-entry S 01 300000 \
>> 	  sched-entry S 02 300000 \
>> 	  sched-entry S 04 300000 \
>> 	  clockid CLOCK_TAI
>> 
>> The configuration format is similar to mqprio. The main difference is
>> the presence of a schedule, built by multiple "sched-entry"
>> definitions, each entry has the following format:
>> 
>>      sched-entry <CMD> <GATE MASK> <INTERVAL>
>> 
>> The only supported <CMD> is "S", which means "SetGateStates",
>
> ...
>
>> +static int str_to_entry_cmd(const char *str)
>> +{
>> +	if (strcmp(str, "S") == 0)
>> +		return TC_TAPRIO_CMD_SET_GATES;
>> +
>> +	if (strcmp(str, "H") == 0)
>> +		return TC_TAPRIO_CMD_SET_AND_HOLD;
>> +
>> +	if (strcmp(str, "R") == 0)
>> +		return TC_TAPRIO_CMD_SET_AND_RELEASE;
>
> If 'S' is the only supported command, what are 'H' and 'R'?

It is the only command that works (for now): taprio is a software only
implementation now.

Just to give some background, 'H' (Set-And-Hold-MAC) and 'R'
(Set-And-Release-MAC) will be used when Frame Preemption is added, 'H'
means that any preemtible frame should have finished being transmitted
before this "entry" starts and frame preemption is disabled, 'R' means
preemptible frames may be transmitted during this entry's interval and
frame preemption is re-enabled.

Will remove these references for now. 

>
>> +
>> +	return -1;
>> +}
>> +
>
>> +
>> +static const char *command_to_str(__u8 cmd)
>> +{
>> +	switch (cmd) {
>> +	case TC_TAPRIO_CMD_SET_GATES:
>> +		return "S";
>> +	case TC_TAPRIO_CMD_SET_AND_HOLD:
>> +		return "H";
>> +	case TC_TAPRIO_CMD_SET_AND_RELEASE:
>> +		return "R";
>> +	default:
>> +		return "Invalid";
>> +	}
>> +}
>
> And can you keep str-to-command and command-to-str helpers close
> together in the code.

Sure. WIll fix it for v2.


Cheers,

[PATCH iproute2 net-next v1 6/6] taprio: Add manpage for tc-taprio(8)

[Vinicius Costa Gomes]

This documents the parameters and provides an example of usage.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
---
 man/man8/tc-taprio.8 | 142 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 142 insertions(+)
 create mode 100644 man/man8/tc-taprio.8

diff --git a/man/man8/tc-taprio.8 b/man/man8/tc-taprio.8
new file mode 100644
index 00000000..92055b43
--- /dev/null
+++ b/man/man8/tc-taprio.8
@@ -0,0 +1,142 @@
+.TH TAPRIO 8 "25 Sept 2018" "iproute2" "Linux"
+.SH NAME
+TAPRIO \- Time Aware Priority Shaper
+.SH SYNOPSIS
+.B tc qdisc ... dev
+dev
+.B parent
+classid
+.B [ handle
+major:
+.B ] taprio num_tc
+tcs
+.ti +8
+.B map
+P0 P1 P2 ...
+.B queues
+count1@offset1 count2@offset2 ...
+.ti +8
+.B base-time
+base-time
+.B clockid
+clockid
+.ti +8
+.B sched-entry
+<command 1> <gate mask 1> <interval 1>
+.ti +8
+.B sched-entry
+<command 2> <gate mask 2> <interval 2>
+.ti +8
+.B sched-entry
+<command 3> <gate mask 3> <interval 3>
+.ti +8
+.B sched-entry
+<command N> <gate mask N> <interval N>
+
+.SH DESCRIPTION
+The TAPRIO qdisc implements a simplified version of the scheduling
+state machine defined by IEEE 802.1Q-2018 Section 8.6.9, which allows
+configuration of a sequence of gate states, where each gate state
+allows outgoing traffic for a subset (potentially empty) of traffic
+classes.
+
+How traffic is mapped to different hardware queues is similar to
+.BR mqprio(8)
+and so the
+.B map
+and
+.Q queues
+parameters have the same meaning.
+
+The other parameters specify the schedule, and at what point in time
+it should start (it can behave as the schedule started in the past).
+
+.SH PARAMETERS
+.TP
+num_tc
+.BR
+Number of traffic classes to use. Up to 16 classes supported.
+
+.TP
+map
+.br
+The priority to traffic class map. Maps priorities 0..15 to a specified
+traffic class. See
+.BR mqprio(8)
+for more details.
+
+.TP
+queues
+.br
+Provide count and offset of queue range for each traffic class. In the
+format,
+.B count@offset.
+Queue ranges for each traffic classes cannot overlap and must be a
+contiguous range of queues.
+
+.TP
+base-time
+.br
+Specifies the instant in nanoseconds, using the reference of
+.B clockid,
+defining the time when the schedule starts. If 'base-time' is a time
+in the past, the schedule will start at
+
+base-time + (N * cycle-time)
+
+where N is the smallest integer so the resulting time is greater than
+"now", and "cycle-time" is the sum of all the intervals of the entries
+in the schedule;
+
+.TP
+clockid
+.br
+Specifies the clock to be used by qdisc's internal timer for measuring
+time and scheduling events.
+
+.TP
+sched-entry
+.br
+There may multiple
+.B sched-entry
+parameters in a single schedule. Each one has the
+
+sched-entry <command> <gatemask> <interval>
+
+format. The only supported <command> is "S", which
+means "SetGateStates", following the IEEE 802.1Q-2018 definition
+(Table 8-7). <gate mask> is a bitmask where each bit is a associated
+with a traffic class, so bit 0 (the least significant bit) being "on"
+means that traffic class 0 is "active" for that schedule entry.
+<interval> is a time duration, in nanoseconds, that specifies for how
+long that state defined by <command> and <gate mask> should be held
+before moving to the next entry.
+
+.SH EXAMPLES
+
+The following example shows how an traffic schedule with three traffic
+classes ("num_tc 3"), which are separated different traffic classes,
+we are going to call these TC 0, TC 1 and TC 2. We could read the
+"map" parameter below as: traffic with priority 3 is classified as TC
+0, priority 2 is classified as TC 1 and the rest is classified as TC
+2.
+
+The schedule will start at instant 1528743495910289987 using the
+reference CLOCK_TAI. The schedule is composed of three entries each of
+300us duration.
+
+.EX
+# tc qdisc replace dev eth0 parent root handle 100 taprio \\
+              num_tc 3 \\
+              map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \\
+              queues 1@0 1@1 2@2 \\
+              base-time 1528743495910289987 \\
+              sched-entry S 01 300000 \\
+              sched-entry S 02 300000 \\
+              sched-entry S 04 300000 \\
+              clockid CLOCK_TAI
+.EE
+
+
+.SH AUTHORS
+Vinicius Costa Gomes <vinicius.gomes@intel.com>
-- 
2.19.0