Introduce a per-VNET flag to enable/disable netisr prcessing on that VNET.

Add accessor functions to toggle the state per VNET.
The base system (vnet0) will always enable itself with the normal
registration. We will share the registered protocol handlers in all
VNETs minimising duplication and management.
Upon disabling netisr processing for a VNET drain the netisr queue from
packets for that VNET.

Update netisr consumers to (de)register on a per-VNET start/teardown using
VNET_SYS(UN)INIT functionality.

The change should be transparent for non-VIMAGE kernels.

Reviewed by:	gnn (, hiren)
Obtained from:	projects/vnet
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D6691

1 files changed, 23 insertions, 5 deletions

diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index c074603..91158b0 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -191,15 +191,33 @@ SYSCTL_PROC(_net_route, OID_AUTO, netisr_maxqlen, CTLTYPE_INT|CTLFLAG_RW,
     "maximum routing socket dispatch queue length");
 
 static void
-rts_init(void)
+vnet_rts_init(void)
 {
 	int tmp;
 
-	if (TUNABLE_INT_FETCH("net.route.netisr_maxqlen", &tmp))
-		rtsock_nh.nh_qlimit = tmp;
-	netisr_register(&rtsock_nh);
+	if (IS_DEFAULT_VNET(curvnet)) {
+		if (TUNABLE_INT_FETCH("net.route.netisr_maxqlen", &tmp))
+			rtsock_nh.nh_qlimit = tmp;
+		netisr_register(&rtsock_nh);
+	}
+#ifdef VIMAGE
+	 else
+		netisr_register_vnet(&rtsock_nh);
+#endif
+}
+VNET_SYSINIT(vnet_rtsock, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD,
+    vnet_rts_init, 0);
+
+#ifdef VIMAGE
+static void
+vnet_rts_uninit(void)
+{
+
+	netisr_unregister_vnet(&rtsock_nh);
 }
-SYSINIT(rtsock, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, rts_init, 0);
+VNET_SYSUNINIT(vnet_rts_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD,
+    vnet_rts_uninit, 0);
+#endif
 
 static int
 raw_input_rts_cb(struct mbuf *m, struct sockproto *proto, struct sockaddr *src,