[lltable] Unify datapath feedback mechamism.

Use newly-create llentry_request_feedback(),
 llentry_mark_used() and llentry_get_hittime() to
 request datapatch usage check and fetch the results
 in the same fashion both in IPv4 and IPv6.

While here, simplify llentry_provide_feedback() wrapper
 by eliminating 1 condition check.

Differential Revision: https://reviews.freebsd.org/D31390

(cherry picked from commit f3a3b061216936b6233d1624dfdba03240d7c045)

2 files changed, 8 insertions, 32 deletions

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index ef50ec9ca964..3eb9d7210afb 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -207,7 +207,6 @@ arptimer(void *arg)
 {
 	struct llentry *lle = (struct llentry *)arg;
 	struct ifnet *ifp;
-	int r_skip_req;
 
 	if (lle->la_flags & LLE_STATIC) {
 		return;
@@ -240,27 +239,17 @@ arptimer(void *arg)
 
 		/*
 		 * Expiration time is approaching.
-		 * Let's try to refresh entry if it is still
-		 * in use.
-		 *
-		 * Set r_skip_req to get feedback from
-		 * fast path. Change state and re-schedule
-		 * ourselves.
+		 * Request usage feedback from the datapath.
+		 * Change state and re-schedule ourselves.
 		 */
-		LLE_REQ_LOCK(lle);
-		lle->r_skip_req = 1;
-		LLE_REQ_UNLOCK(lle);
+		llentry_request_feedback(lle);
 		lle->ln_state = ARP_LLINFO_VERIFY;
 		callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit);
 		LLE_WUNLOCK(lle);
 		CURVNET_RESTORE();
 		return;
 	case ARP_LLINFO_VERIFY:
-		LLE_REQ_LOCK(lle);
-		r_skip_req = lle->r_skip_req;
-		LLE_REQ_UNLOCK(lle);
-
-		if (r_skip_req == 0 && lle->la_preempt > 0) {
+		if (llentry_get_hittime(lle) > 0 && lle->la_preempt > 0) {
 			/* Entry was used, issue refresh request */
 			struct epoch_tracker et;
 			struct in_addr dst;
@@ -532,7 +521,7 @@ arpresolve_full(struct ifnet *ifp, int is_gw, int flags, struct mbuf *m,
 		bcopy(lladdr, desten, ll_len);
 
 		/* Notify LLE code that the entry was used by datapath */
-		llentry_mark_used(la);
+		llentry_provide_feedback(la);
 		if (pflags != NULL)
 			*pflags = la->la_flags & (LLE_VALID|LLE_IFADDR);
 		if (plle) {
@@ -656,7 +645,7 @@ arpresolve(struct ifnet *ifp, int is_gw, struct mbuf *m,
 		if (pflags != NULL)
 			*pflags = LLE_VALID | (la->r_flags & RLLE_IFADDR);
 		/* Notify the LLE handling code that the entry was used. */
-		llentry_mark_used(la);
+		llentry_provide_feedback(la);
 		if (plle) {
 			LLE_ADDREF(la);
 			*plle = la;
@@ -1225,7 +1214,7 @@ arp_check_update_lle(struct arphdr *ah, struct in_addr isaddr, struct ifnet *ifp
 			return;
 
 		/* Clear fast path feedback request if set */
-		la->r_skip_req = 0;
+		llentry_mark_used(la);
 	}
 
 	arp_mark_lle_reachable(la);
diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index bcf071a81e0e..d1dd2b31b6ef 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -1265,19 +1265,6 @@ in_lltable_destroy_lle_unlocked(epoch_context_t ctx)
 }
 
 /*
- * Called by the datapath to indicate that
- * the entry was used.
- */
-static void
-in_lltable_mark_used(struct llentry *lle)
-{
-
-	LLE_REQ_LOCK(lle);
-	lle->r_skip_req = 0;
-	LLE_REQ_UNLOCK(lle);
-}
-
-/*
  * Called by LLE_FREE_LOCKED when number of references
  * drops to zero.
  */
@@ -1681,7 +1668,7 @@ in_lltattach(struct ifnet *ifp)
 	llt->llt_fill_sa_entry = in_lltable_fill_sa_entry;
 	llt->llt_free_entry = in_lltable_free_entry;
 	llt->llt_match_prefix = in_lltable_match_prefix;
-	llt->llt_mark_used = in_lltable_mark_used;
+	llt->llt_mark_used = llentry_mark_used;
  	lltable_link(llt);
 
 	return (llt);