Stop grabing the KERNEL_LOCK() for running protocol input routines.

The NET_LOCK() is already held in this thread and is now enough.

People interested in ARP/bridge(4)/switch(4)/pipex(4)/pppoe(4)
performances can now push the KERNEL_LOCK() without depending on
other subsystems/drivers.

Tested by Hrvoje Popovski.

ok bluhm@, visa@

diff --git a/sys/net/if.c b/sys/net/if.c
index 5dc00bd..0c2517a 100644 (file)
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if.c,v 1.535 2018/01/09 06:24:14 dlg Exp $    */
+/*     $OpenBSD: if.c,v 1.536 2018/01/09 17:50:57 mpi Exp $    */
 /*     $NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $  */
 
 /*
@@ -920,7 +920,6 @@ if_netisr(void *unused)
 {
        int n, t = 0;
 
-       KERNEL_LOCK();
        NET_LOCK();
 
        while ((n = netisr) != 0) {
@@ -934,8 +933,11 @@ if_netisr(void *unused)
                atomic_clearbits_int(&netisr, n);
 
 #if NETHER > 0
-               if (n & (1 << NETISR_ARP))
+               if (n & (1 << NETISR_ARP)) {
+                       KERNEL_LOCK();
                        arpintr();
+                       KERNEL_UNLOCK();
+               }
 #endif
                if (n & (1 << NETISR_IP))
                        ipintr();
@@ -944,35 +946,52 @@ if_netisr(void *unused)
                        ip6intr();
 #endif
 #if NPPP > 0
-               if (n & (1 << NETISR_PPP))
+               if (n & (1 << NETISR_PPP)) {
+                       KERNEL_LOCK();
                        pppintr();
+                       KERNEL_UNLOCK();
+               }
 #endif
 #if NBRIDGE > 0
-               if (n & (1 << NETISR_BRIDGE))
+               if (n & (1 << NETISR_BRIDGE)) {
+                       KERNEL_LOCK();
                        bridgeintr();
+                       KERNEL_UNLOCK();
+               }
 #endif
 #if NSWITCH > 0
-               if (n & (1 << NETISR_SWITCH))
+               if (n & (1 << NETISR_SWITCH)) {
+                       KERNEL_LOCK();
                        switchintr();
+                       KERNEL_UNLOCK();
+               }
 #endif
 #if NPPPOE > 0
-               if (n & (1 << NETISR_PPPOE))
+               if (n & (1 << NETISR_PPPOE)) {
+                       KERNEL_LOCK();
                        pppoeintr();
+                       KERNEL_UNLOCK();
+               }
 #endif
 #ifdef PIPEX
-               if (n & (1 << NETISR_PIPEX))
+               if (n & (1 << NETISR_PIPEX)) {
+                       KERNEL_LOCK();
                        pipexintr();
+                       KERNEL_UNLOCK();
+               }
 #endif
                t |= n;
        }
 
 #if NPFSYNC > 0
-       if (t & (1 << NETISR_PFSYNC))
+       if (t & (1 << NETISR_PFSYNC)) {
+               KERNEL_LOCK();
                pfsyncintr();
+               KERNEL_UNLOCK();
+       }
 #endif
 
        NET_UNLOCK();
-       KERNEL_UNLOCK();
 }
 
 void