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	diff --git a/sys/net/if_llatbl.h b/sys/net/if_llatbl.h
	--- a/sys/net/if_llatbl.h
	+++ b/sys/net/if_llatbl.h
	@@ -268,6 +268,7 @@
	void llentry_request_feedback(struct llentry *lle);
	void llentry_mark_used(struct llentry *lle);
	time_t llentry_get_hittime(struct llentry *lle);
	+int llentry_get_upper_family(const struct llentry *lle, int default_family);

	/*
	* Notify the LLE code that the entry was used by datapath.
	diff --git a/sys/net/if_llatbl.c b/sys/net/if_llatbl.c
	--- a/sys/net/if_llatbl.c
	+++ b/sys/net/if_llatbl.c
	@@ -59,6 +59,7 @@
	#include <net/if_var.h>
	#include <net/route.h>
	#include <net/route/route_ctl.h>
	+#include <net/route/route_debug.h>
	#include <net/vnet.h>
	#include <netinet/if_ether.h>
	#include <netinet6/in6_var.h>
	@@ -418,6 +419,67 @@
	return (NULL);
	}

	+/*
	+ * Retrieves upper protocol family for the llentry.
	+ * By default, all "normal" (e.g. upper_family == transport_family)
	+ * llentries have r_family set to 0.
	+ * Thus, use @default_family in that regard, otherwise use r_family.
	+ *
	+ * Returns upper protocol family
	+ */
	+int
	+llentry_get_upper_family(const struct llentry *lle, int default_family)
	+{
	+ return (lle->r_family == 0 ? default_family : lle->r_family);
	+}
	+
	+/*
	+ * Prints llentry @lle data into provided buffer.
	+ * Example: lle/inet/valid/em0/1.2.3.4
	+ *
	+ * Returns @buf.
	+ */
	+char *
	+llentry_print_buf(const struct llentry lle, struct ifnet ifp, int family,
	+ char *buf, size_t bufsize)
	+{
	+ char abuf[INET6_ADDRSTRLEN];
	+
	+ const char *valid = (lle->r_flags & RLLE_VALID) ? "valid" : "no_l2";
	+ const char *upper_str = rib_print_family(llentry_get_upper_family(lle, family));
	+
	+ switch (family) {
	+#ifdef INET
	+ case AF_INET:
	+ inet_ntop(AF_INET, &lle->r_l3addr.addr4, abuf, sizeof(abuf));
	+ snprintf(buf, bufsize, "lle/%s/%s/%s/%s", upper_str,
	+ valid, if_name(ifp), abuf);
	+ break;
	+#endif
	+#ifdef INET6
	+ case AF_INET6:
	+ inet_ntop(AF_INET6, &lle->r_l3addr.addr6, abuf, sizeof(abuf));
	+ snprintf(buf, bufsize, "lle/%s/%s/%s/%s", upper_str,
	+ valid, if_name(ifp), abuf);
	+ break;
	+#endif
	+ default:
	+ snprintf(buf, bufsize, "lle/%s/%s/%s/????", upper_str,
	+ valid, if_name(ifp));
	+ break;
	+ }
	+
	+ return (buf);
	+}
	+
	+char *
	+llentry_print_buf_lltable(const struct llentry lle, char buf, size_t bufsize)
	+{
	+ struct lltable *tbl = lle->lle_tbl;
	+
	+ return (llentry_print_buf(lle, lltable_get_ifp(tbl), lltable_get_af(tbl), buf, bufsize));
	+}
	+
	/*
	* Requests feedback from the datapath.
	* First packet using @lle should result in
	diff --git a/sys/net/route.h b/sys/net/route.h
	--- a/sys/net/route.h
	+++ b/sys/net/route.h
	@@ -448,6 +448,7 @@
	void rib_flush_routes_family(int family);
	struct nhop_object rib_lookup(uint32_t fibnum, const struct sockaddr dst,
	uint32_t flags, uint32_t flowid);
	+const char *rib_print_family(int family);
	#endif

	#endif
	diff --git a/sys/net/route/nhop_ctl.c b/sys/net/route/nhop_ctl.c
	--- a/sys/net/route/nhop_ctl.c
	+++ b/sys/net/route/nhop_ctl.c
	@@ -52,6 +52,11 @@
	#include <net/route/nhop_var.h>
	#include <net/vnet.h>

	+#define DEBUG_MOD_NAME nhop_ctl
	+#define DEBUG_MAX_LEVEL LOG_DEBUG
	+#include <net/route/route_debug.h>
	+_DECLARE_DEBUG(LOG_INFO);
	+
	/*
	* This file contains core functionality for the nexthop ("nhop") route subsystem.
	* The business logic needed to create nexhop objects is implemented here.
	@@ -91,8 +96,6 @@
	static void destroy_nhop_epoch(epoch_context_t ctx);
	static void destroy_nhop(struct nhop_priv *nh_priv);

	-static void print_nhop(const char prefix, const struct nhop_object nh);
	-
	_Static_assert(__offsetof(struct nhop_object, nh_ifp) == 32,
	"nhop_object: wrong nh_ifp offset");
	_Static_assert(sizeof(struct nhop_object) <= 128,
	@@ -139,7 +142,7 @@
	nh->gw_sa.sa_family == AF_LINK) {
	aifp = ifnet_byindex(nh->gwl_sa.sdl_index);
	if (aifp == NULL) {
	- DPRINTF("unable to get aifp for %s index %d",
	+ FIB_NH_LOG(LOG_WARNING, nh, "unable to get aifp for %s index %d",
	if_name(nh->nh_ifp), nh->gwl_sa.sdl_index);
	}
	}
	@@ -226,7 +229,7 @@
	struct sockaddr_dl sdl = (struct sockaddr_dl )gw;
	struct ifnet *ifp = ifnet_byindex(sdl->sdl_index);
	if (ifp == NULL) {
	- DPRINTF("invalid ifindex %d", sdl->sdl_index);
	+ FIB_NH_LOG(LOG_WARNING, nh, "invalid ifindex %d", sdl->sdl_index);
	return (EINVAL);
	}
	fill_sdl_from_ifp(&nh->gwl_sa, ifp);
	@@ -244,7 +247,7 @@
	* happy.
	*/
	if (gw->sa_len > sizeof(struct sockaddr_in6)) {
	- DPRINTF("nhop SA size too big: AF %d len %u",
	+ FIB_NH_LOG(LOG_WARNING, nh, "nhop SA size too big: AF %d len %u",
	gw->sa_family, gw->sa_len);
	return (ENOMEM);
	}
	@@ -525,7 +528,7 @@
	ifa_free(nh->nh_ifa);
	return (false);
	}
	- DPRINTF("AIFP: %p nh_ifp %p", nh->nh_aifp, nh->nh_ifp);
	+ FIB_NH_LOG(LOG_DEBUG, nh, "AIFP: %p nh_ifp %p", nh->nh_aifp, nh->nh_ifp);
	if (!if_try_ref(nh->nh_ifp)) {
	ifa_free(nh->nh_ifa);
	if_rele(nh->nh_aifp);
	@@ -552,7 +555,7 @@
	if (nh->nh_pksent == NULL) {
	uma_zfree(nhops_zone, nh);
	RTSTAT_INC(rts_nh_alloc_failure);
	- DPRINTF("nh_alloc_finalize failed");
	+ FIB_NH_LOG(LOG_WARNING, nh, "counter_u64_alloc() failed");
	return (ENOMEM);
	}

	@@ -560,7 +563,7 @@
	counter_u64_free(nh->nh_pksent);
	uma_zfree(nhops_zone, nh);
	RTSTAT_INC(rts_nh_alloc_failure);
	- DPRINTF("nh_alloc_finalize failed - reference failure");
	+ FIB_NH_LOG(LOG_WARNING, nh, "interface reference failed");
	return (EAGAIN);
	}

	@@ -574,8 +577,6 @@

	nh_priv->nh_fibnum = ctl->ctl_rh->rib_fibnum;

	- print_nhop("FINALIZE", nh);
	-
	if (link_nhop(ctl, nh_priv) == 0) {
	/*
	* Adding nexthop to the datastructures
	@@ -583,47 +584,20 @@
	* the epoch end, as nexthop is not used
	* and return.
	*/
	- DPRINTF("link_nhop failed!");
	+ char nhbuf[48];
	+ FIB_NH_LOG(LOG_WARNING, nh, "failed to link %s",
	+ nhop_print_buf(nh, nhbuf, sizeof(nhbuf)));
	destroy_nhop(nh_priv);

	return (ENOBUFS);
	}

	- return (0);
	-}
	-
	-static void
	-print_nhop_sa(char buf, size_t buflen, const struct sockaddr sa)
	-{
	-
	- if (sa->sa_family == AF_INET) {
	- const struct sockaddr_in *sin4;
	- sin4 = (const struct sockaddr_in *)sa;
	- inet_ntop(AF_INET, &sin4->sin_addr, buf, buflen);
	- } else if (sa->sa_family == AF_INET6) {
	- const struct sockaddr_in6 *sin6;
	- sin6 = (const struct sockaddr_in6 *)sa;
	- inet_ntop(AF_INET6, &sin6->sin6_addr, buf, buflen);
	- } else if (sa->sa_family == AF_LINK) {
	- const struct sockaddr_dl *sdl;
	- sdl = (const struct sockaddr_dl *)sa;
	- snprintf(buf, buflen, "if#%d", sdl->sdl_index);
	- } else
	- snprintf(buf, buflen, "af:%d", sa->sa_family);
	-}
	-
	-static void
	-print_nhop(const char prefix, const struct nhop_object nh)
	-{
	- char src_buf[INET6_ADDRSTRLEN], addr_buf[INET6_ADDRSTRLEN];
	-
	- print_nhop_sa(src_buf, sizeof(src_buf), nh->nh_ifa->ifa_addr);
	- print_nhop_sa(addr_buf, sizeof(addr_buf), &nh->gw_sa);
	+#if DEBUG_MAX_LEVEL >= LOG_DEBUG
	+ char nhbuf[48];
	+ FIB_NH_LOG(LOG_DEBUG, nh, "finalized: %s", nhop_print_buf(nh, nhbuf, sizeof(nhbuf)));
	+#endif

	- DPRINTF("%s nhop priv %p: AF %d ifp %p %s addr %s src %p %s aifp %p %s mtu %d nh_flags %X",
	- prefix, nh->nh_priv, nh->nh_priv->nh_upper_family, nh->nh_ifp,
	- if_name(nh->nh_ifp), addr_buf, nh->nh_ifa, src_buf, nh->nh_aifp,
	- if_name(nh->nh_aifp), nh->nh_mtu, nh->nh_flags);
	+ return (0);
	}

	static void
	@@ -633,8 +607,6 @@

	nh = nh_priv->nh;

	- print_nhop("DEL", nh);
	-
	if_rele(nh->nh_ifp);
	if_rele(nh->nh_aifp);
	ifa_free(nh->nh_ifa);
	@@ -682,6 +654,11 @@
	if (!refcount_release(&nh_priv->nh_refcnt))
	return;

	+#if DEBUG_MAX_LEVEL >= LOG_DEBUG
	+ char nhbuf[48];
	+ FIB_NH_LOG(LOG_DEBUG, nh, "deleting %s", nhop_print_buf(nh, nhbuf, sizeof(nhbuf)));
	+#endif
	+
	/*
	* There are only 2 places, where nh_linked can be decreased:
	* rib destroy (nhops_destroy_rib) and this function.
	@@ -706,7 +683,9 @@
	ctl = nh_priv->nh_control;
	if (unlink_nhop(ctl, nh_priv) == NULL) {
	/* Do not try to reclaim */
	- DPRINTF("Failed to unlink nexhop %p", nh_priv);
	+ char nhbuf[48];
	+ FIB_NH_LOG(LOG_WARNING, nh, "failed to unlink %s",
	+ nhop_print_buf(nh, nhbuf, sizeof(nhbuf)));
	NET_EPOCH_EXIT(et);
	return;
	}
	@@ -844,6 +823,45 @@

	}

	+/*
	+ * Prints nexthop @nh data in the provided @buf.
	+ * Example: nh#33/inet/em0/192.168.0.1
	+ */
	+char *
	+nhop_print_buf(const struct nhop_object nh, char buf, size_t bufsize)
	+{
	+ char abuf[INET6_ADDRSTRLEN];
	+ struct nhop_priv *nh_priv = nh->nh_priv;
	+ const char *upper_str = rib_print_family(nh->nh_priv->nh_upper_family);
	+
	+ switch (nh->gw_sa.sa_family) {
	+#ifdef INET
	+ case AF_INET:
	+ inet_ntop(AF_INET, &nh->gw4_sa.sin_addr, abuf, sizeof(abuf));
	+ snprintf(buf, bufsize, "nh#%d/%s/%s/%s", nh_priv->nh_idx, upper_str,
	+ if_name(nh->nh_ifp), abuf);
	+ break;
	+#endif
	+#ifdef INET6
	+ case AF_INET6:
	+ inet_ntop(AF_INET6, &nh->gw6_sa.sin6_addr, abuf, sizeof(abuf));
	+ snprintf(buf, bufsize, "nh#%d/%s/%s/%s", nh_priv->nh_idx, upper_str,
	+ if_name(nh->nh_ifp), abuf);
	+ break;
	+#endif
	+ case AF_LINK:
	+ snprintf(buf, bufsize, "nh#%d/%s/%s/resolve", nh_priv->nh_idx, upper_str,
	+ if_name(nh->nh_ifp));
	+ break;
	+ default:
	+ snprintf(buf, bufsize, "nh#%d/%s/%s/????", nh_priv->nh_idx, upper_str,
	+ if_name(nh->nh_ifp));
	+ break;
	+ }
	+
	+ return (buf);
	+}
	+
	/*
	* Dumps a single entry to sysctl buffer.
	*
	@@ -866,8 +884,6 @@
	size_t addrs_len;
	int error;

	- //DPRINTF("Dumping: head %p nh %p flags %X req %p\n", rh, nh, nh->nh_flags, w);
	-
	memset(&arpc, 0, sizeof(arpc));

	arpc.rtm.rtm_msglen = sizeof(arpc);
	@@ -949,7 +965,10 @@
	ctl = rh->nh_control;

	NHOPS_RLOCK(ctl);
	- DPRINTF("NHDUMP: count=%u", ctl->nh_head.items_count);
	+#if DEBUG_MAX_LEVEL >= LOG_DEBUG
	+ FIB_LOG(LOG_DEBUG, rh->rib_fibnum, rh->rib_family, "dump %u items",
	+ ctl->nh_head.items_count);
	+#endif
	CHT_SLIST_FOREACH(&ctl->nh_head, nhops, nh_priv) {
	error = dump_nhop_entry(rh, nh_priv->nh, w);
	if (error != 0) {
	diff --git a/sys/net/route/route_ctl.c b/sys/net/route/route_ctl.c
	--- a/sys/net/route/route_ctl.c
	+++ b/sys/net/route/route_ctl.c
	@@ -118,6 +118,9 @@
	VNET_DEFINE_STATIC(uma_zone_t, rtzone);
	#define V_rtzone VNET(rtzone)

	+/* Debug bits */
	+SYSCTL_NODE(_net_route, OID_AUTO, debug, CTLFLAG_RD \| CTLFLAG_MPSAFE, 0, "");
	+
	void
	vnet_rtzone_init()
	{
	@@ -1430,6 +1433,20 @@
	}
	}

	+const char *
	+rib_print_family(int family)
	+{
	+ switch (family) {
	+ case AF_INET:
	+ return ("inet");
	+ case AF_INET6:
	+ return ("inet6");
	+ case AF_LINK:
	+ return ("link");
	+ }
	+ return ("unknown");
	+}
	+
	static void
	rib_notify(struct rib_head *rnh, enum rib_subscription_type type,
	struct rib_cmd_info *rc)
	diff --git a/sys/net/route/route_debug.h b/sys/net/route/route_debug.h
	new file mode 100644
	--- /dev/null
	+++ b/sys/net/route/route_debug.h
	@@ -0,0 +1,141 @@
	+/*-
	+ * Copyright (c) 2021
	+ * Alexander V. Chernikov <melifaro@FreeBSD.org>
	+ *
	+ * Redistribution and use in source and binary forms, with or without
	+ * modification, are permitted provided that the following conditions
	+ * are met:
	+ * 1. Redistributions of source code must retain the above copyright
	+ * notice, this list of conditions and the following disclaimer.
	+ * 2. Redistributions in binary form must reproduce the above copyright
	+ * notice, this list of conditions and the following disclaimer in the
	+ * documentation and/or other materials provided with the distribution.
	+ * 3. Neither the name of the University nor the names of its contributors
	+ * may be used to endorse or promote products derived from this software
	+ * without specific prior written permission.
	+ *
	+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	+ * SUCH DAMAGE.
	+ *
	+ * $FreeBSD$
	+ */
	+
	+#ifndef _NET_ROUTE_DEBUG_H_
	+#define _NET_ROUTE_DEBUG_H_
	+
	+#include <sys/sysctl.h>
	+#include <sys/syslog.h>
	+
	+
	+/* DEBUG logic */
	+#if defined(DEBUG_MOD_NAME) && defined(DEBUG_MAX_LEVEL)
	+
	+#define DEBUG_VAR_NAME _DEBUG_VAR_NAME(DEBUG_MOD_NAME)
	+#define _DEBUG_VAR_NAME(a) _DEBUG_VAR_NAME_INDIRECT(a)
	+#define _DEBUG_VAR_NAME_INDIRECT(prefix) prefix##_debug_level
	+
	+#define DEBUG_PREFIX_NAME _DEBUG_PREFIX_NAME(DEBUG_MOD_NAME)
	+#define _DEBUG_PREFIX_NAME(n) __DEBUG_PREFIX_NAME(n)
	+#define __DEBUG_PREFIX_NAME(n) #n
	+
	+#define _DECLARE_DEBUG(_default_level) \
	+ SYSCTL_DECL(_net_route_debug); \
	+ static int DEBUG_VAR_NAME = _default_level; \
	+ SYSCTL_INT(_net_route_debug, OID_AUTO, DEBUG_VAR_NAME, \
	+ CTLFLAG_RW \| CTLFLAG_RWTUN, \
	+ &(DEBUG_VAR_NAME), 0, "debuglevel")
	+
	+/* Additional tracing levels not defined by log.h */
	+#ifndef LOG_DEBUG2
	+#define LOG_DEBUG2 8
	+#endif
	+#ifndef LOG_DEBUG3
	+#define LOG_DEBUG3 9
	+#endif
	+
	+#define _output printf
	+#define _DEBUG_PASS_MSG(_l) (DEBUG_VAR_NAME >= (_l))
	+
	+/*
	+ * Logging for events specific for particular family and fib
	+ * Example: [nhop_neigh] inet.0 find_lle: nhop nh#4/inet/vtnet0/10.0.0.1: mapped to lle NULL
	+ */
	+#define FIB_LOG(_l, _fib, _fam, _fmt, ...) FIB_LOG_##_l(_l, _fib, _fam, _fmt, ## __VA_ARGS__)
	+#define _FIB_LOG(_l, _fib, _fam, _fmt, ...) if (_DEBUG_PASS_MSG(_l)) { \
	+ _output("[" DEBUG_PREFIX_NAME "] %s.%u %s: " _fmt "\n", rib_print_family(_fam), _fib, __func__, ##__VA_ARGS__); \
	+}
	+
	+/* Same as FIB_LOG, but uses nhop to get fib and family */
	+#define FIB_NH_LOG(_l, _nh, _fmt, ...) FIB_LOG_##_l(_l, nhop_get_fibnum(_nh), nhop_get_upper_family(_nh), _fmt, ## __VA_ARGS__)
	+
	+/*
	+ * Generic logging for routing subsystem
	+ * Example: [nhop_neigh] nhops_update_neigh: L2 prepend update from lle/inet/valid/vtnet0/10.0.0.157
	+ */
	+#define RT_LOG(_l, _fmt, ...) RT_LOG_##_l(_l, _fmt, ## __VA_ARGS__)
	+#define _RT_LOG(_l, _fmt, ...) if (_DEBUG_PASS_MSG(_l)) { \
	+ _output("[" DEBUG_PREFIX_NAME "] %s: " _fmt "\n", __func__, ##__VA_ARGS__); \
	+}
	+
	+
	+/*
	+ * Wrapper logic to avoid compiling high levels of debugging messages for production systems.
	+ */
	+#if DEBUG_MAX_LEVEL>=LOG_DEBUG2
	+#define FIB_LOG_LOG_DEBUG3 _FIB_LOG
	+#define RT_LOG_LOG_DEBUG3 _RT_LOG
	+#else
	+#define FIB_LOG_LOG_DEBUG3(_l, _fib, _fam, _fmt, ...)
	+#define RT_LOG_LOG_DEBUG3(_l, _fmt, ...)
	+#endif
	+#if DEBUG_MAX_LEVEL>=LOG_DEBUG2
	+#define FIB_LOG_LOG_DEBUG2 _FIB_LOG
	+#define RT_LOG_LOG_DEBUG2 _RT_LOG
	+#else
	+#define FIB_LOG_LOG_DEBUG2(_l, _fib, _fam, _fmt, ...)
	+#define RT_LOG_LOG_DEBUG2(_l, _fmt, ...)
	+#endif
	+#if DEBUG_MAX_LEVEL>=LOG_DEBUG
	+#define FIB_LOG_LOG_DEBUG _FIB_LOG
	+#define RT_LOG_LOG_DEBUG _RT_LOG
	+#else
	+#define FIB_LOG_LOG_DEBUG(_l, _fib, _fam, _fmt, ...)
	+#define RT_LOG_LOG_DEBUG(_l, _fmt, ...)
	+#endif
	+#if DEBUG_MAX_LEVEL>=LOG_INFO
	+#define FIB_LOG_LOG_INFO _FIB_LOG
	+#define RT_LOG_LOG_INFO _RT_LOG
	+#else
	+#define FIB_LOG_LOG_INFO(_l, _fib, _fam, _fmt, ...)
	+#define RT_LOG_LOG_INFO(_l, _fmt, ...)
	+#endif
	+#define FIB_LOG_LOG_NOTICE _FIB_LOG
	+#define FIB_LOG_LOG_ERR _FIB_LOG
	+#define FIB_LOG_LOG_WARNING _FIB_LOG
	+#define RT_LOG_LOG_NOTICE _RT_LOG
	+#define RT_LOG_LOG_ERR _RT_LOG
	+#define RT_LOG_LOG_WARNING _RT_LOG
	+
	+#endif
	+
	+/* Helpers for fancy-printing various objects */
	+struct nhop_object;
	+struct llentry;
	+struct nhop_neigh;
	+
	+char nhop_print_buf(const struct nhop_object nh, char *buf, size_t bufsize);
	+char llentry_print_buf(const struct llentry lle, struct ifnet ifp, int family, char buf,
	+ size_t bufsize);
	+char llentry_print_buf_lltable(const struct llentry lle, char *buf, size_t bufsize);
	+char neigh_print_buf(const struct nhop_neigh nn, char *buf, size_t bufsize);
	+
	+#endif

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