SMP locking for ARP.

1 files changed, 21 insertions, 6 deletions

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index f5e23d5..16780b1 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -130,6 +130,13 @@ static struct llinfo_arp
 static void	in_arpinput(struct mbuf *);
 #endif
 
+static struct	mtx arp_mtx;
+
+#define	ARP_LOCK_INIT()	\
+    mtx_init(&arp_mtx, "arp mutex", NULL, MTX_DEF | MTX_RECURSE)
+#define	ARP_LOCK()	mtx_lock(&arp_mtx)
+#define	ARP_UNLOCK()	mtx_unlock(&arp_mtx)
+
 /*
  * Timeout routine.  Age arp_tab entries periodically.
  */
@@ -138,17 +145,20 @@ static void
 arptimer(ignored_arg)
 	void *ignored_arg;
 {
+	struct llinfo_arp *la, *ola;
 	int s = splnet();
-	register struct llinfo_arp *la = LIST_FIRST(&llinfo_arp);
-	struct llinfo_arp *ola;
 
-	timeout(arptimer, (caddr_t)0, arpt_prune * hz);
-	while ((ola = la) != 0) {
-		register struct rtentry *rt = la->la_rt;
+	ARP_LOCK();
+	la = LIST_FIRST(&llinfo_arp);
+	timeout(arptimer, NULL, arpt_prune * hz);
+	while (la != NULL) {
+		struct rtentry *rt = la->la_rt;
+		ola = la;
 		la = LIST_NEXT(la, la_le);
 		if (rt->rt_expire && rt->rt_expire <= time_second)
-			arptfree(ola); /* timer has expired, clear */
+			arptfree(ola);		/* timer has expired, clear */
 	}
+	ARP_UNLOCK();
 	splx(s);
 }
 
@@ -225,7 +235,9 @@ arp_rtrequest(req, rt, info)
 		Bzero(la, sizeof(*la));
 		la->la_rt = rt;
 		rt->rt_flags |= RTF_LLINFO;
+		ARP_LOCK();
 		LIST_INSERT_HEAD(&llinfo_arp, la, la_le);
+		ARP_UNLOCK();
 
 #ifdef INET
 		/*
@@ -273,7 +285,9 @@ arp_rtrequest(req, rt, info)
 		if (la == 0)
 			break;
 		arp_inuse--;
+		ARP_LOCK();
 		LIST_REMOVE(la, la_le);
+		ARP_UNLOCK();
 		rt->rt_llinfo = 0;
 		rt->rt_flags &= ~RTF_LLINFO;
 		if (la->la_hold)
@@ -951,6 +965,7 @@ arp_init(void)
 	arpintrq.ifq_maxlen = 50;
 	mtx_init(&arpintrq.ifq_mtx, "arp_inq", NULL, MTX_DEF);
 	LIST_INIT(&llinfo_arp);
+	ARP_LOCK_INIT();
 	register_netisr(NETISR_ARP, arpintr);
 }