Change the initialization methodology for global variables scheduled

for virtualization.

Instead of initializing the affected global variables at instatiation,
assign initial values to them in initializer functions.  As a rule,
initialization at instatiation for such variables should never be
introduced again from now on.  Furthermore, enclose all instantiations
of such global variables in #ifdef VIMAGE_GLOBALS blocks.

Essentialy, this change should have zero functional impact.  In the next
phase of merging network stack virtualization infrastructure from
p4/vimage branch, the new initialization methology will allow us to
switch between using global variables and their counterparts residing in
virtualization containers with minimum code churn, and in the long run
allow us to intialize multiple instances of such container structures.

Discussed at:	devsummit Strassburg
Reviewed by:	bz, julian
Approved by:	julian (mentor)
Obtained from:	//depot/projects/vimage-commit2/...
X-MFC after:	never
Sponsored by:	NLnet Foundation, The FreeBSD Foundation

1 files changed, 22 insertions, 10 deletions

diff --git a/sys/net/if_gif.c b/sys/net/if_gif.c
index db8835e..57bfaab 100644
--- a/sys/net/if_gif.c
+++ b/sys/net/if_gif.c
@@ -94,7 +94,18 @@
  */
 static struct mtx gif_mtx;
 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
+
+#ifdef VIMAGE_GLOBALS
 static LIST_HEAD(, gif_softc) gif_softc_list;
+static int max_gif_nesting;
+static int parallel_tunnels;
+#ifdef INET
+int ip_gif_ttl;
+#endif
+#ifdef INET6
+int ip6_gif_hlim;
+#endif
+#endif
 
 void	(*ng_gif_input_p)(struct ifnet *ifp, struct mbuf **mp, int af);
 void	(*ng_gif_input_orphan_p)(struct ifnet *ifp, struct mbuf *m, int af);
@@ -123,9 +134,6 @@ SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
  */
 #define MAX_GIF_NEST 1
 #endif
-#ifndef VIMAGE
-static int max_gif_nesting = MAX_GIF_NEST;
-#endif
 SYSCTL_V_INT(V_NET, vnet_gif, _net_link_gif, OID_AUTO, max_nesting,
     CTLFLAG_RW, max_gif_nesting, 0, "Max nested tunnels");
 
@@ -140,11 +148,6 @@ SYSCTL_V_INT(V_NET, vnet_gif, _net_inet6_ip6, IPV6CTL_GIF_HLIM,
  * pair of addresses.  Some applications require this functionality so
  * we allow control over this check here.
  */
-#ifdef XBONEHACK
-static int parallel_tunnels = 1;
-#else
-static int parallel_tunnels = 0;
-#endif
 SYSCTL_V_INT(V_NET, vnet_gif, _net_link_gif, OID_AUTO, parallel_tunnels,
     CTLFLAG_RW, parallel_tunnels, 0, "Allow parallel tunnels?");
 
@@ -251,12 +254,21 @@ gifmodevent(mod, type, data)
 	switch (type) {
 	case MOD_LOAD:
 		mtx_init(&gif_mtx, "gif_mtx", NULL, MTX_DEF);
-		LIST_INIT(&V_gif_softc_list);
-		if_clone_attach(&gif_cloner);
 
+		LIST_INIT(&V_gif_softc_list);
+		V_max_gif_nesting = MAX_GIF_NEST;
+#ifdef XBONEHACK
+		V_parallel_tunnels = 1;
+#else
+		V_parallel_tunnels = 0;
+#endif
+#ifdef INET
+		V_ip_gif_ttl = GIF_TTL;
+#endif
 #ifdef INET6
 		V_ip6_gif_hlim = GIF_HLIM;
 #endif
+		if_clone_attach(&gif_cloner);
 
 		break;
 	case MOD_UNLOAD: