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, 12 insertions, 4 deletions

diff --git a/sys/netinet/tcp_reass.c b/sys/netinet/tcp_reass.c
index 6f55e11..5f47be0 100644
--- a/sys/netinet/tcp_reass.c
+++ b/sys/netinet/tcp_reass.c
@@ -74,25 +74,28 @@ __FBSDID("$FreeBSD$");
 #include <netinet/tcp_debug.h>
 #endif /* TCPDEBUG */
 
+#ifdef VIMAGE_GLOBALS
+static int tcp_reass_maxseg;
+int tcp_reass_qsize;
+static int tcp_reass_maxqlen;
+static int tcp_reass_overflows;
+#endif
+
 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW, 0,
     "TCP Segment Reassembly Queue");
 
-static int tcp_reass_maxseg = 0;
 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_tcp_reass, OID_AUTO, maxsegments,
     CTLFLAG_RDTUN, tcp_reass_maxseg, 0,
     "Global maximum number of TCP Segments in Reassembly Queue");
 
-int tcp_reass_qsize = 0;
 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_tcp_reass, OID_AUTO, cursegments,
     CTLFLAG_RD, tcp_reass_qsize, 0,
     "Global number of TCP Segments currently in Reassembly Queue");
 
-static int tcp_reass_maxqlen = 48;
 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_tcp_reass, OID_AUTO, maxqlen,
     CTLFLAG_RW, tcp_reass_maxqlen, 0,
     "Maximum number of TCP Segments per individual Reassembly Queue");
 
-static int tcp_reass_overflows = 0;
 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_tcp_reass, OID_AUTO, overflows,
     CTLFLAG_RD, tcp_reass_overflows, 0,
     "Global number of TCP Segment Reassembly Queue Overflows");
@@ -114,6 +117,11 @@ tcp_reass_init(void)
 {
 	INIT_VNET_INET(curvnet);
 
+	V_tcp_reass_maxseg = 0;
+	V_tcp_reass_qsize = 0;
+	V_tcp_reass_maxqlen = 48;
+	V_tcp_reass_overflows = 0;
+
 	V_tcp_reass_maxseg = nmbclusters / 16;
 	TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments",
 	    &V_tcp_reass_maxseg);