Remove kernel locks from the ARP input path. Caller if_netisr()

grabs the exclusive netlock and that is sufficent for in_arpinput()
and arpcache().
with kn@; OK mvs@; tested by Hrvoje Popovski

diff --git a/sys/net/if.c b/sys/net/if.c
index dbd9890..ab0ec63 100644 (file)
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if.c,v 1.686 2023/04/05 19:35:23 bluhm Exp $  */
+/*     $OpenBSD: if.c,v 1.687 2023/04/07 22:02:58 bluhm Exp $  */
 /*     $NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $  */
 
 /*
@@ -927,11 +927,8 @@ if_netisr(void *unused)
                atomic_clearbits_int(&netisr, n);
 
 #if NETHER > 0
-               if (n & (1 << NETISR_ARP)) {
-                       KERNEL_LOCK();
+               if (n & (1 << NETISR_ARP))
                        arpintr();
-                       KERNEL_UNLOCK();
-               }
 #endif
                if (n & (1 << NETISR_IP))
                        ipintr();

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index 46aa3c2..5614636 100644 (file)
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_ether.c,v 1.260 2023/04/05 21:51:47 bluhm Exp $    */
+/*     $OpenBSD: if_ether.c,v 1.261 2023/04/07 22:02:58 bluhm Exp $    */
 /*     $NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $    */
 
 /*
@@ -609,12 +609,7 @@ in_arpinput(struct ifnet *ifp, struct mbuf *m)
                    "address %s\n", addr, ether_sprintf(ea->arp_sha));
                itaddr = isaddr;
        } else if (rt != NULL) {
-               int error;
-
-               KERNEL_LOCK();
-               error = arpcache(ifp, ea, rt);
-               KERNEL_UNLOCK();
-               if (error)
+               if (arpcache(ifp, ea, rt))
                        goto out;
        }
 
@@ -656,7 +651,7 @@ arpcache(struct ifnet *ifp, struct ether_arp *ea, struct rtentry *rt)
        time_t uptime;
        int changed = 0;
 
-       KERNEL_ASSERT_LOCKED();
+       NET_ASSERT_LOCKED_EXCLUSIVE();
        KASSERT(sdl != NULL);
 
        /*