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, 13 insertions, 1 deletions

diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index d7fc9eeaf33a..a897d6c3e1d3 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -217,8 +217,15 @@ ip6_init(void)
 	V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR;
 
 	/* Skip global initialization stuff for non-default instances. */
-	if (!IS_DEFAULT_VNET(curvnet))
+#ifdef VIMAGE
+	if (!IS_DEFAULT_VNET(curvnet)) {
+		netisr_register_vnet(&ip6_nh);
+#ifdef RSS
+		netisr_register_vnet(&ip6_direct_nh);
+#endif
 		return;
+	}
+#endif
 
 	pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
 	if (pr == NULL)
@@ -310,6 +317,11 @@ ip6_destroy(void *unused __unused)
 {
 	int error;
 
+#ifdef RSS
+	netisr_unregister_vnet(&ip6_direct_nh);
+#endif
+	netisr_unregister_vnet(&ip6_nh);
+
 	if ((error = pfil_head_unregister(&V_inet6_pfil_hook)) != 0)
 		printf("%s: WARNING: unable to unregister pfil hook, "
 		    "error %d\n", __func__, error);