ml_purge for netinet/if_ether.c

[David Gwynne]

ml_purge returns how many mbufs they freed, so we can decrement the
la_hold_total with that instead of inside an ml_dequeue/m_freem
loop.

ok?

Index: netinet/if_ether.c
===================================================================
RCS file: /cvs/src/sys/netinet/if_ether.c,v
retrieving revision 1.182
diff -u -p -r1.182 if_ether.c
--- netinet/if_ether.c  2 Nov 2015 15:05:23 -0000       1.182
+++ netinet/if_ether.c  3 Nov 2015 06:15:03 -0000
@@ -141,7 +141,6 @@ arp_rtrequest(struct ifnet *ifp, int req
        struct sockaddr *gate = rt->rt_gateway;
        struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
        struct ifaddr *ifa;
-       struct mbuf *m;
 
        if (!arpinit_done) {
                static struct timeout arptimer_to;
@@ -243,10 +242,7 @@ arp_rtrequest(struct ifnet *ifp, int req
                LIST_REMOVE(la, la_list);
                rt->rt_llinfo = 0;
                rt->rt_flags &= ~RTF_LLINFO;
-               while ((m = ml_dequeue(&la->la_ml)) != NULL) {
-                       la_hold_total--;
-                       m_freem(m);
-               }
+               la_hold_total -= ml_purge(&la->la_ml);
                pool_put(&arp_pool, la);
        }
 }
@@ -395,10 +391,7 @@ arpresolve(struct ifnet *ifp, struct rte
                ml_enqueue(&la->la_ml, m);
                la_hold_total++;
        } else {
-               while ((mh = ml_dequeue(&la->la_ml)) != NULL) {
-                       la_hold_total--;
-                       m_freem(mh);
-               }
+               la_hold_total -= ml_purge(&la->la_ml);
                m_freem(m);
        }
 
@@ -431,10 +424,7 @@ arpresolve(struct ifnet *ifp, struct rte
                                rt->rt_flags |= RTF_REJECT;
                                rt->rt_expire += arpt_down;
                                la->la_asked = 0;
-                               while ((mh = ml_dequeue(&la->la_ml)) != NULL) {
-                                       la_hold_total--;
-                                       m_freem(mh);
-                               }
+                               la_hold_total -= ml_purge(&la->la_ml);
                        }
                }
        }