integ/base/linuxptp/debian/patches/0037-Enhance-phc2sys-to-accept-multiple-ptp4l-inputs.patch

From 2a6ddfe1b9700ce8e0c62da8a7a4f2edcd4e1cad Mon Sep 17 00:00:00 2001
From: Andre Mauricio Zelak <andre.zelak@windriver.com>
Date: Sun, 18 Jun 2023 20:58:34 -0300
Subject: [PATCH 37/47] Enhance phc2sys to accept multiple ptp4l inputs

A new configuration option called ha_enabled was created. When it is set 1
multiple ptp4l inputs are accepted and the high availability algorithms
are enabled.

In addition to ha_enabled 1 a set of interfaces must also be provided.
Each interface is one-to-one mapped to a clock source, and must be
associated to an unique ptp4l instance using the ha_uds_address
configuration option.

For example:

ha_enabled 1

[ens1f1]
ha_uds_address /var/run/ptp4l-ptp-inst1

[ens1f2]
ha_uds_address /var/run/ptp4l-ptp-inst2

A maximum of 128 interfaces is supported.

Regression: verify non HA phc2sys configuration
PASS: Verify auto configuration is still accepted.
PASS: Verify manual configuration with a single clock is still accepted.
PASS: Verify mix of manual and auto configuration is denied.
PASS: Verify manual configuration with zero clock sources is denied.

Test Plan: verify HA configuration
PASS: Verify HA is disabled by default.
PASS: Verify HA configuration with 1 or more clock source is accepted.
PASS: Verify ha_uds_address default value.

Reviewed-by: Cole Walker <cole.walker@windriver.com>
Reviewed-by: Andre Fernando Zanella Kantek <andrefernandozanella.kantek@windriver.com>
Signed-off-by: Andre Mauricio Zelak <andre.zelak@windriver.com>

[commit 705fe12b294216c7b5797f48d83ff97fcc076294 upstream]
[commit e730f006cb56ac55932220c1afff5470de875200 upstream]
[commit df8fa0492771f6babb75254619337edb6041daea upstream]
[commit 0201340fa5abc17634bfb4d0b2a386d218d3095b upstream]
[commit dd7400f4eb548dfb2acfb6ebaf53a6d77b9c5da2 upstream]
[commit 904fb44ecebd448f9b2952dd287ac2b5db8249db upstream]
[commit 56dcd671d5241b589dc44b776fec9b2752496477 upstream]
[commit 7e5617afe8837b77629cc04c9e3abb38ae64678c upstream]
[commit 5ea8af40b8b5e4680d8a8e1a19482c28f95ce6b3 upstream]
[commit 3d38367a3151845ec543ab9125e2d0a0aefa2f56 upstream]
[commit 17a4d6805597fd6ddb911b8246e7b131a42f9191 upstream]
[commit 1650d972f4fe9bb39807536df2594d1a85aabf9c upstream]

Signed-off-by: Andre Mauricio Zelak <andre.zelak@windriver.com>
---
 config.c    |  17 +++
 config.h    |   2 +
 phc2sys.c   | 337 +++++++++++++++++++++++++++++++++++++---------------
 pmc_agent.c |  17 ---
 pmc_agent.h |  21 +++-
 uds.c       |  19 ++-
 6 files changed, 294 insertions(+), 119 deletions(-)

diff --git a/config.c b/config.c
index d45e948..b97e5d7 100644
--- a/config.c
+++ b/config.c
@@ -250,6 +250,8 @@ struct config_item config_tab[] = {
 	GLOB_ITEM_INT("G.8275.defaultDS.localPriority", 128, 1, UINT8_MAX),
 	PORT_ITEM_INT("G.8275.portDS.localPriority", 128, 1, UINT8_MAX),
 	GLOB_ITEM_INT("gmCapable", 1, 0, 1),
+	GLOB_ITEM_INT("ha_enabled", 0, 0, 1),
+	PORT_ITEM_STR("ha_uds_address", "/var/run/ptp4l"),
 	GLOB_ITEM_ENU("hwts_filter", HWTS_FILTER_NORMAL, hwts_filter_enu),
 	PORT_ITEM_INT("hybrid_e2e", 0, 0, 1),
 	PORT_ITEM_INT("ignore_source_id", 0, 0, 1),
@@ -996,6 +998,21 @@ char *config_get_string(struct config *cfg, const char *section,
 	return ci->val.s;
 }
 
+unsigned int config_get_interfaces(struct config *cfg, char *interfaces[], unsigned int max)
+{
+	struct interface *iface = NULL;
+	unsigned int counter = 0;
+
+	STAILQ_FOREACH(iface, &cfg->interfaces, list) {
+		if (counter == max) {
+			pr_err("bug: too many interfaces!");
+			return (unsigned int)-1;
+		}
+		interfaces[counter++] = interface_name(iface);
+	}
+	return counter;
+}
+
 int config_harmonize_onestep(struct config *cfg)
 {
 	enum timestamp_type tstype = config_get_int(cfg, NULL, "time_stamping");
diff --git a/config.h b/config.h
index 14d2f64..645fb42 100644
--- a/config.h
+++ b/config.h
@@ -64,6 +64,8 @@ int config_get_int(struct config *cfg, const char *section,
 char *config_get_string(struct config *cfg, const char *section,
 			const char *option);
 
+unsigned int config_get_interfaces(struct config *cfg, char *interfaces[], unsigned int max);
+
 int config_harmonize_onestep(struct config *cfg);
 
 static inline struct option *config_long_options(struct config *cfg)
diff --git a/phc2sys.c b/phc2sys.c
index c9fabd7..a4afe01 100644
--- a/phc2sys.c
+++ b/phc2sys.c
@@ -64,6 +64,12 @@
 
 #define PHC_PPS_OFFSET_LIMIT 10000000
 
+#define MAX_SRC_CLOCKS 128
+
+#define PORT_INDEX_TO_PORT_ID(port, index) (((((unsigned int) port) & 0xFF) << 8) || (((unsigned int) index) & 0xFF))
+#define PORT_ID_TO_PORT(id) ((((unsigned int) id) >> 8) & 0xFF)
+#define PORT_ID_TO_INDEX(id) (((unsigned int) id) & 0xFF)
+
 struct clock {
 	LIST_ENTRY(clock) list;
 	LIST_ENTRY(clock) dst_list;
@@ -85,6 +91,7 @@ struct clock {
 	struct stats *freq_stats;
 	struct stats *delay_stats;
 	struct clockcheck *sanity_check;
+	struct pmc_agent *node;
 };
 
 struct port {
@@ -103,7 +110,7 @@ struct phc2sys_private {
 	int forced_sync_offset;
 	int kernel_leap;
 	int state_changed;
-	struct pmc_agent *node;
+	LIST_HEAD(pmc_agent_head, pmc_agent) pmc_agents;
 	LIST_HEAD(port_head, port) ports;
 	LIST_HEAD(clock_head, clock) clocks;
 	LIST_HEAD(dst_clock_head, clock) dst_clocks;
@@ -260,6 +267,18 @@ static struct port *port_get(struct phc2sys_private *priv, unsigned int number)
 	return NULL;
 }
 
+static struct port *port_get_by_clock(struct phc2sys_private *priv, struct clock * clock)
+{
+	struct port *p, *port = NULL;
+	LIST_FOREACH(p, &priv->ports, list) {
+		if (p->clock == clock) {
+			port = p;
+			break;
+		}
+	}
+	return port;
+}
+
 static struct port *port_add(struct phc2sys_private *priv, unsigned int number,
 			     char *device)
 {
@@ -293,6 +312,42 @@ static struct port *port_add(struct phc2sys_private *priv, unsigned int number,
 	return p;
 }
 
+static struct pmc_agent *pmc_agent_get(struct phc2sys_private *priv, unsigned int index)
+{
+	struct pmc_agent *node;
+	LIST_FOREACH(node, &priv->pmc_agents, list) {
+		if (node->index == index) {
+			break;
+		}
+	}
+	return node;
+}
+
+static struct pmc_agent *pmc_agent_add(struct phc2sys_private *priv, unsigned int index)
+{
+	struct pmc_agent *node = pmc_agent_get(priv, index);
+	if (node)
+		return node;
+
+	node = pmc_agent_create();
+	if (!node) {
+		pr_err("failed to allocate memory for a pmc agent");
+		return NULL;
+	}
+
+	node->index = index;
+	LIST_INSERT_HEAD(&priv->pmc_agents, node, list);
+	return node;
+}
+
+static void pmc_agent_cleanup(struct phc2sys_private *priv)
+{
+	struct pmc_agent *node, *tmp;
+	LIST_FOREACH_SAFE(node, &priv->pmc_agents, list, tmp) {
+		pmc_agent_destroy(node);
+	}
+}
+
 static void clock_reinit(struct phc2sys_private *priv, struct clock *clock,
 			 int new_state)
 {
@@ -302,12 +357,17 @@ static void clock_reinit(struct phc2sys_private *priv, struct clock *clock,
 	struct sk_ts_info ts_info;
 	char iface[IFNAMSIZ];
 	clockid_t clkid = CLOCK_INVALID;
+	struct pmc_agent *node;
+	unsigned int pmc_index;
 
 	LIST_FOREACH(p, &priv->ports, list) {
 		if (p->clock != clock) {
 			continue;
 		}
-		err = pmc_agent_query_port_properties(priv->node, 1000,
+
+		pmc_index = PORT_ID_TO_INDEX(p->number);
+		node = pmc_agent_get(priv, pmc_index);
+		err = pmc_agent_query_port_properties(node, 1000,
 						      p->number, &state,
 						      &timestamping, iface);
 		if (!err) {
@@ -638,12 +698,13 @@ static int do_pps_loop(struct phc2sys_private *priv, struct clock *clock,
 	int64_t pps_offset, phc_offset, phc_delay;
 	uint64_t pps_ts, phc_ts;
 	clockid_t src = priv->master->clkid;
+	struct pmc_agent *node = LIST_FIRST(&priv->pmc_agents);
 
 	priv->master->source_label = "pps";
 
 	if (src == CLOCK_INVALID) {
 		/* The sync offset can't be applied with PPS alone. */
-		pmc_agent_set_sync_offset(priv->node, 0);
+		pmc_agent_set_sync_offset(node, 0);
 	} else {
 		enable_pps_output(priv->master->clkid);
 	}
@@ -674,7 +735,7 @@ static int do_pps_loop(struct phc2sys_private *priv, struct clock *clock,
 			pps_offset = pps_ts - phc_ts;
 		}
 
-		if (pmc_agent_update(priv->node) < 0)
+		if (pmc_agent_update(node) < 0)
 			continue;
 		update_clock(priv, clock, pps_offset, pps_ts, -1);
 	}
@@ -706,6 +767,7 @@ static int do_loop(struct phc2sys_private *priv, int subscriptions)
 	uint64_t ts;
 	int64_t offset, delay;
 	int err;
+	struct pmc_agent *node = NULL;
 
 	interval.tv_sec = priv->phc_interval;
 	interval.tv_nsec = (priv->phc_interval - interval.tv_sec) * 1e9;
@@ -713,22 +775,28 @@ static int do_loop(struct phc2sys_private *priv, int subscriptions)
 	while (is_running()) {
 		clock_nanosleep(CLOCK_MONOTONIC, 0, &interval, NULL);
 
-		if (pmc_agent_update(priv->node) < 0) {
-			continue;
-		}
+		LIST_FOREACH(node, &priv->pmc_agents, list) {
+			if (pmc_agent_update(node) < 0) {
+				continue;
+			}
 
-		if (subscriptions) {
-			run_pmc_events(priv->node);
-			if (priv->state_changed) {
-				/* force getting offset, as it may have
-				 * changed after the port state change */
-				if (pmc_agent_query_utc_offset(priv->node, 1000)) {
-					pr_err("failed to get UTC offset");
-					continue;
+			if (subscriptions) {
+				run_pmc_events(node);
+				if (priv->state_changed) {
+					/* force getting offset, as it may have
+					 * changed after the port state change */
+					if (pmc_agent_query_utc_offset(node, 1000)) {
+						pr_err("failed to get UTC offset");
+						continue;
+					}
 				}
-				reconfigure(priv);
 			}
 		}
+
+		if (subscriptions && priv->state_changed) {
+			reconfigure(priv);
+		}
+
 		if (!priv->master)
 			continue;
 
@@ -859,55 +927,65 @@ static int auto_init_ports(struct phc2sys_private *priv, int add_rt)
 	struct clock *clock;
 	struct port *port;
 	unsigned int i;
+	struct pmc_agent *node = NULL;
+	unsigned int retries, port_number;
 
-	while (1) {
-		if (!is_running()) {
-			return -1;
-		}
-		err = pmc_agent_query_dds(priv->node, 1000);
-		if (!err) {
-			break;
-		}
-		if (err == -ETIMEDOUT) {
-			pr_notice("Waiting for ptp4l...");
-		} else {
-			return -1;
+	LIST_FOREACH(node, &priv->pmc_agents, list) {
+		retries = 0;
+		while(retries < 10) {
+			if (!is_running()) {
+				return -1;
+			}
+			err = pmc_agent_query_dds(node, 1000);
+			if (!err) {
+				break;
+			}
+			if (err == -ETIMEDOUT) {
+				pr_notice("Waiting for ptp4l...");
+				retries++;
+			} else {
+				return -1;
+			}
 		}
-	}
 
-	number_ports = pmc_agent_get_number_ports(priv->node);
-	if (number_ports <= 0) {
-		pr_err("failed to get number of ports");
-		return -1;
-	}
-
-	err = pmc_agent_subscribe(priv->node, 1000);
-	if (err) {
-		pr_err("failed to subscribe");
-		return -1;
-	}
-
-	for (i = 1; i <= number_ports; i++) {
-		err = pmc_agent_query_port_properties(priv->node, 1000, i,
-						      &state, &timestamping,
-						      iface);
-		if (err == -ENODEV) {
-			/* port does not exist, ignore the port */
+		number_ports = pmc_agent_get_number_ports(node);
+		if (number_ports <= 0) {
+			pr_err("failed to get number of ports");
 			continue;
 		}
+
+		err = pmc_agent_subscribe(node, 1000);
 		if (err) {
-			pr_err("failed to get port properties");
-			return -1;
-		}
-		if (timestamping == TS_SOFTWARE) {
-			/* ignore ports with software time stamping */
+			pr_err("failed to subscribe");
 			continue;
 		}
-		port = port_add(priv, i, iface);
-		if (!port)
-			return -1;
-		port->state = normalize_state(state);
+
+		for (i = 1; i <= number_ports; i++) {
+			err = pmc_agent_query_port_properties(node, 1000, i,
+								&state, &timestamping,
+								iface);
+			if (err == -ENODEV) {
+				/* port does not exist, ignore the port */
+				continue;
+			}
+			if (err) {
+				pr_err("failed to get port properties");
+				break;
+			}
+			if (timestamping == TS_SOFTWARE) {
+				/* ignore ports with software time stamping */
+				continue;
+			}
+			port_number = PORT_INDEX_TO_PORT_ID(i, node->index);
+			port = port_add(priv, port_number, iface);
+			if (!port)
+				return -1;
+			port->state = normalize_state(state);
+			/* map clock to pmc agent node */
+			port->clock->node = node;
+		}
 	}
+
 	if (LIST_EMPTY(&priv->clocks)) {
 		pr_err("no suitable ports available");
 		return -1;
@@ -926,9 +1004,11 @@ static int auto_init_ports(struct phc2sys_private *priv, int add_rt)
 	}
 
 	/* get initial offset */
-	if (pmc_agent_query_utc_offset(priv->node, 1000)) {
-		pr_err("failed to get UTC offset");
-		return -1;
+	LIST_FOREACH(node, &priv->pmc_agents, list) {
+		if (pmc_agent_query_utc_offset(node, 1000)) {
+			pr_err("failed to get UTC offset");
+			continue;
+		}
 	}
 	return 0;
 }
@@ -937,9 +1017,12 @@ static int auto_init_ports(struct phc2sys_private *priv, int add_rt)
 static int clock_handle_leap(struct phc2sys_private *priv, struct clock *clock,
 			     int64_t offset, uint64_t ts)
 {
-	int clock_leap, node_leap = pmc_agent_get_leap(priv->node);
+	int clock_leap, node_leap;
+	struct pmc_agent *node = priv->master->node;
+
+	node_leap = pmc_agent_get_leap(node);
 
-	clock->sync_offset = pmc_agent_get_sync_offset(priv->node);
+	clock->sync_offset = pmc_agent_get_sync_offset(node);
 
 	if ((node_leap || clock->leap_set) &&
 	    clock->is_utc != priv->master->is_utc) {
@@ -980,7 +1063,7 @@ static int clock_handle_leap(struct phc2sys_private *priv, struct clock *clock,
 		}
 	}
 
-	if (pmc_agent_utc_offset_traceable(priv->node) &&
+	if (pmc_agent_utc_offset_traceable(node) &&
 	    clock->utc_offset_set != clock->sync_offset) {
 		if (clock->clkid == CLOCK_REALTIME)
 			sysclk_set_tai_offset(clock->sync_offset);
@@ -1034,7 +1117,8 @@ static void usage(char *progname)
 
 int main(int argc, char *argv[])
 {
-	char *config = NULL, *dst_name = NULL, *progname, *src_name = NULL;
+	char *config = NULL, *dst_name = NULL, *progname;
+	char *src_names[MAX_SRC_CLOCKS];
 	char uds_local[MAX_IFNAME_SIZE + 1];
 	int autocfg = 0, c, domain_number = 0, index, ntpshm_segment, offset;
 	int pps_fd = -1, print_level = LOG_INFO, r = -1, rt = 0;
@@ -1047,7 +1131,11 @@ int main(int argc, char *argv[])
 	struct phc2sys_private priv = {
 		.phc_readings = 5,
 		.phc_interval = 1.0,
+		.master = NULL,
 	};
+	struct pmc_agent *node = NULL;
+	unsigned int i, src_cnt = 0;
+	int ha_enabled = 0;
 
 	handle_term_signals();
 
@@ -1055,8 +1143,8 @@ int main(int argc, char *argv[])
 	if (!cfg) {
 		return -1;
 	}
-	priv.node = pmc_agent_create();
-	if (!priv.node) {
+	node = pmc_agent_add(&priv, 0);
+	if (!node) {
 		return -1;
 	}
 
@@ -1102,7 +1190,11 @@ int main(int argc, char *argv[])
 				"'-i' has been deprecated. please use '-s' instead.\n");
             /* fallthrough */
 		case 's':
-			src_name = strdup(optarg);
+			if (src_cnt == MAX_SRC_CLOCKS) {
+				fprintf(stderr, "too many source clocks\n");
+				goto bad_usage;
+			}
+			src_names[src_cnt++] = optarg;
 			break;
 		case 'E':
 			if (!strcasecmp(optarg, "pi")) {
@@ -1153,7 +1245,7 @@ int main(int argc, char *argv[])
 			if (get_arg_val_i(c, optarg, &offset, INT_MIN, INT_MAX)) {
 				goto end;
 			}
-			pmc_agent_set_sync_offset(priv.node, offset);
+			pmc_agent_set_sync_offset(node, offset);
 			priv.forced_sync_offset = -1;
 			break;
 		case 'L':
@@ -1241,12 +1333,22 @@ int main(int argc, char *argv[])
 		return c;
 	}
 
-	if (autocfg && (src_name || dst_name || pps_fd >= 0 || wait_sync || priv.forced_sync_offset)) {
+	if (src_cnt == 0) {
+		/* get the source interface list from configuration file */
+		src_cnt = config_get_interfaces(cfg, src_names, MAX_SRC_CLOCKS);
+		if (src_cnt == (unsigned int)-1) {
+			fprintf(stderr, "too many interfaces in configuration file\n");
+			fprintf(stderr, "maximum number of interfaces is %u\n", MAX_SRC_CLOCKS);
+			goto bad_usage;
+		}
+	}
+
+	if (autocfg && (src_cnt > 0 || dst_name || pps_fd >= 0 || wait_sync || priv.forced_sync_offset)) {
 		fprintf(stderr,
 			"autoconfiguration cannot be mixed with manual config options.\n");
 		goto bad_usage;
 	}
-	if (!autocfg && pps_fd < 0 && !src_name) {
+	if (!autocfg && pps_fd < 0 && src_cnt == 0) {
 		fprintf(stderr,
 			"autoconfiguration or valid source clock must be selected.\n");
 		goto bad_usage;
@@ -1282,7 +1384,7 @@ int main(int argc, char *argv[])
 		 getpid());
 
 	if (autocfg) {
-		if (init_pmc_node(cfg, priv.node, uds_local,
+		if (init_pmc_node(cfg, node, uds_local,
 				  phc2sys_recv_subscribed, &priv))
 			goto end;
 		if (auto_init_ports(&priv, rt) < 0)
@@ -1291,15 +1393,26 @@ int main(int argc, char *argv[])
 		goto end;
 	}
 
-	src = clock_add(&priv, src_name);
-	free(src_name);
-	if (!src) {
-		fprintf(stderr,
-			"valid source clock must be selected.\n");
+	ha_enabled = config_get_int(cfg, NULL, "ha_enabled");
+	if (!ha_enabled && src_cnt > 1) {
+		fprintf(stderr, "too many source clocks\n");
+		fprintf(stderr, "Use 'ha_enabled 1' to accept more than one source clocks\n");
 		goto bad_usage;
 	}
-	src->state = PS_SLAVE;
-	priv.master = src;
+
+	for (i = 0; i < src_cnt; ++i) {
+		src = clock_add(&priv, src_names[i]);
+		if (!src) {
+			fprintf(stderr,
+				"invalid source clock '%s'.\n", src_names[i]);
+			goto bad_usage;
+		}
+		src->state = PS_SLAVE;
+		/* select the first clock */
+		if (priv.master == NULL) {
+			priv.master = src;
+		}
+	}
 
 	dst = clock_add(&priv, dst_name ? dst_name : "CLOCK_REALTIME");
 	free(dst_name);
@@ -1320,32 +1433,58 @@ int main(int argc, char *argv[])
 	r = -1;
 
 	if (wait_sync) {
-		if (init_pmc_node(cfg, priv.node, uds_local,
-				  phc2sys_recv_subscribed, &priv))
-			goto end;
+		i = 0;
+		for (src = LIST_FIRST(&priv.clocks);
+			 src != NULL;
+			 src = LIST_NEXT(src, list)) {
 
-		while (is_running()) {
-			r = run_pmc_wait_sync(priv.node, 1000);
-			if (r < 0)
-				goto end;
-			if (r > 0)
-				break;
-			else
-				pr_notice("Waiting for ptp4l...");
-		}
+			/* skip dst clock */
+			if (src == dst) {
+				continue;
+			}
 
-		if (!priv.forced_sync_offset) {
-			r = pmc_agent_query_utc_offset(priv.node, 1000);
-			if (r) {
-				pr_err("failed to get UTC offset");
+			if (i > 0) {
+				node = pmc_agent_add(&priv, i);
+				if (!node)
+					goto end;
+			}
+
+			/* uds local is formated '/var/run/phc2sys.<pid>.<source_interface>' */
+			snprintf(uds_local, sizeof(uds_local), "/var/run/phc2sys.%d.%s",
+				getpid(), src->device);
+
+			if (init_pmc_node(cfg, node, uds_local,
+					phc2sys_recv_subscribed, &priv))
 				goto end;
+
+			/* map clock to pmc agent node */
+			src->node = node;
+
+			while (is_running()) {
+				r = run_pmc_wait_sync(node, 1000);
+				if (r < 0)
+					goto end;
+				if (r > 0)
+					break;
+				else
+					pr_notice("Waiting for ptp4l...");
+			}
+
+			if (!priv.forced_sync_offset) {
+				r = pmc_agent_query_utc_offset(node, 1000);
+				if (r) {
+					pr_err("failed to get UTC offset");
+					goto end;
+				}
+			}
+
+			if (priv.forced_sync_offset ||
+				(src->clkid != CLOCK_REALTIME && dst->clkid != CLOCK_REALTIME) ||
+				src->clkid == CLOCK_INVALID) {
+				pmc_agent_disable(node);
 			}
-		}
 
-		if (priv.forced_sync_offset ||
-		    (src->clkid != CLOCK_REALTIME && dst->clkid != CLOCK_REALTIME) ||
-		    src->clkid == CLOCK_INVALID) {
-			pmc_agent_disable(priv.node);
+			++i;
 		}
 	}
 
@@ -1359,7 +1498,7 @@ int main(int argc, char *argv[])
 	}
 
 end:
-	pmc_agent_destroy(priv.node);
+	pmc_agent_cleanup(&priv);
 	clock_cleanup(&priv);
 	port_cleanup(&priv);
 	config_destroy(cfg);
diff --git a/pmc_agent.c b/pmc_agent.c
index 3034f65..d13f569 100644
--- a/pmc_agent.c
+++ b/pmc_agent.c
@@ -34,23 +34,6 @@
  * renewed.
  */
 
-struct pmc_agent {
-	struct pmc *pmc;
-	uint64_t pmc_last_update;
-
-	struct defaultDS dds;
-	bool dds_valid;
-	int leap;
-	int pmc_ds_requested;
-	bool stay_subscribed;
-	int sync_offset;
-	int utc_offset_traceable;
-
-	/* Callback on message reception */
-	pmc_node_recv_subscribed_t *recv_subscribed;
-	void *recv_context;
-};
-
 static void send_subscription(struct pmc_agent *node)
 {
 	struct subscribe_events_np sen;
diff --git a/pmc_agent.h b/pmc_agent.h
index dd34d30..5f25984 100644
--- a/pmc_agent.h
+++ b/pmc_agent.h
@@ -26,11 +26,28 @@
 
 #include "pmc_common.h"
 
-struct pmc_agent;
-
 typedef int pmc_node_recv_subscribed_t(void *context, struct ptp_message *msg,
 				       int excluded);
 
+struct pmc_agent {
+	LIST_ENTRY(pmc_agent) list;
+	struct pmc *pmc;
+	uint64_t pmc_last_update;
+
+	struct defaultDS dds;
+	bool dds_valid;
+	int leap;
+	int pmc_ds_requested;
+	bool stay_subscribed;
+	int sync_offset;
+	int utc_offset_traceable;
+	unsigned int index;
+
+	/* Callback on message reception */
+	pmc_node_recv_subscribed_t *recv_subscribed;
+	void *recv_context;
+};
+
 int init_pmc_node(struct config *cfg, struct pmc_agent *agent, const char *uds,
 		  pmc_node_recv_subscribed_t *recv_subscribed, void *context);
 int run_pmc_wait_sync(struct pmc_agent *agent, int timeout);
diff --git a/uds.c b/uds.c
index 641a672..57d4796 100644
--- a/uds.c
+++ b/uds.c
@@ -55,11 +55,13 @@ static int uds_close(struct transport *t, struct fdarray *fda)
 static int uds_open(struct transport *t, struct interface *iface, struct fdarray *fda,
 		    enum timestamp_type tt)
 {
-	char *uds_path = config_get_string(t->cfg, NULL, "uds_address");
+	char *uds_path = NULL;
 	struct uds *uds = container_of(t, struct uds, t);
 	const char *name = interface_name(iface);
 	struct sockaddr_un sa;
 	int fd, err;
+	char *point = NULL, *source = NULL;
+	int ha_enabled = config_get_int(t->cfg, NULL, "ha_enabled");
 
 	fd = socket(AF_LOCAL, SOCK_DGRAM, 0);
 	if (fd < 0) {
@@ -82,6 +84,21 @@ static int uds_open(struct transport *t, struct interface *iface, struct fdarray
 	/* For client use, pre load the server path. */
 	memset(&sa, 0, sizeof(sa));
 	sa.sun_family = AF_LOCAL;
+
+	if (!ha_enabled) {
+		uds_path = config_get_string(t->cfg, NULL, "uds_address");
+	} else {
+		/* The interface name is formated as '/var/run/phc2sys.<pid>.<source>'.
+		   The last item is the source interface. */
+		point = strtok(name, ".");
+		while(point != NULL) {
+			source = point;
+			point = strtok(NULL, ".");
+		}
+
+		uds_path = config_get_string(t->cfg, source, "ha_uds_address");
+	}
+
 	strncpy(sa.sun_path, uds_path, sizeof(sa.sun_path) - 1);
 	uds->address.sun = sa;
 	uds->address.len = sizeof(sa);
-- 
2.25.1