Build on Jeff Roberson's linker-set based dynamic per-CPU allocator

(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)

1 files changed, 27 insertions, 43 deletions

diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index 0e93aec..9c97988 100644
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -72,7 +72,6 @@ __FBSDID("$FreeBSD$");
 #include <netinet6/scope6_var.h>
 #include <netinet6/nd6.h>
 #include <netinet/icmp6.h>
-#include <netinet6/vinet6.h>
 
 #include <sys/limits.h>
 
@@ -83,32 +82,32 @@ __FBSDID("$FreeBSD$");
 
 #define SIN6(s) ((struct sockaddr_in6 *)s)
 
-#ifdef VIMAGE_GLOBALS
-int nd6_prune;
-int nd6_delay;
-int nd6_umaxtries;
-int nd6_mmaxtries;
-int nd6_useloopback;
-int nd6_gctimer;
+VNET_DEFINE(int, nd6_prune);
+VNET_DEFINE(int, nd6_delay);
+VNET_DEFINE(int, nd6_umaxtries);
+VNET_DEFINE(int, nd6_mmaxtries);
+VNET_DEFINE(int, nd6_useloopback);
+VNET_DEFINE(int, nd6_gctimer);
 
 /* preventing too many loops in ND option parsing */
-int nd6_maxndopt;
+static VNET_DEFINE(int, nd6_maxndopt);
+VNET_DEFINE(int, nd6_maxnudhint);
+static VNET_DEFINE(int, nd6_maxqueuelen);
+#define	V_nd6_maxndopt			VNET_GET(nd6_maxndopt)
+#define	V_nd6_maxqueuelen		VNET_GET(nd6_maxqueuelen)
 
-int nd6_maxnudhint;
-int nd6_maxqueuelen;
-
-int nd6_debug;
+VNET_DEFINE(int, nd6_debug);
 
 /* for debugging? */
 #if 0
 static int nd6_inuse, nd6_allocated;
 #endif
 
-struct nd_drhead nd_defrouter;
-struct nd_prhead nd_prefix;
+VNET_DEFINE(struct nd_drhead, nd_defrouter);
+VNET_DEFINE(struct nd_prhead, nd_prefix);
 
-int nd6_recalc_reachtm_interval;
-#endif /* VIMAGE_GLOBALS */
+VNET_DEFINE(int, nd6_recalc_reachtm_interval);
+#define	V_nd6_recalc_reachtm_interval	VNET_GET(nd6_recalc_reachtm_interval)
 
 static struct sockaddr_in6 all1_sa;
 
@@ -121,18 +120,19 @@ static struct llentry *nd6_free(struct llentry *, int);
 static void nd6_llinfo_timer(void *);
 static void clear_llinfo_pqueue(struct llentry *);
 
-#ifdef VIMAGE_GLOBALS
-struct callout nd6_slowtimo_ch;
-struct callout nd6_timer_ch;
-extern struct callout in6_tmpaddrtimer_ch;
-extern int dad_ignore_ns;
-extern int dad_maxtry;
-#endif
+static VNET_DEFINE(struct callout, nd6_slowtimo_ch);
+#define	V_nd6_slowtimo_ch		VNET_GET(nd6_slowtimo_ch)
+
+VNET_DEFINE(struct callout, nd6_timer_ch);
+
+VNET_DECLARE(int, dad_ignore_ns);
+VNET_DECLARE(int, dad_maxtry);
+#define	V_dad_ignore_ns			VNET_GET(dad_ignore_ns)
+#define	V_dad_maxtry			VNET_GET(dad_maxtry)
 
 void
 nd6_init(void)
 {
-	INIT_VNET_INET6(curvnet);
 	int i;
 
 	V_nd6_prune	= 1;	/* walk list every 1 seconds */
@@ -193,7 +193,6 @@ nd6_init(void)
 void
 nd6_destroy()
 {
-	INIT_VNET_INET6(curvnet);
 
 	callout_drain(&V_nd6_slowtimo_ch);
 	callout_drain(&V_nd6_timer_ch);
@@ -249,7 +248,6 @@ nd6_setmtu(struct ifnet *ifp)
 void
 nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi)
 {
-	INIT_VNET_INET6(ifp->if_vnet);
 	u_int32_t omaxmtu;
 
 	omaxmtu = ndi->maxmtu;
@@ -358,7 +356,6 @@ nd6_option(union nd_opts *ndopts)
 int
 nd6_options(union nd_opts *ndopts)
 {
-	INIT_VNET_INET6(curvnet);
 	struct nd_opt_hdr *nd_opt;
 	int i = 0;
 
@@ -492,7 +489,6 @@ nd6_llinfo_timer(void *arg)
 		panic("ln ifp == NULL");
 
 	CURVNET_SET(ifp->if_vnet);
-	INIT_VNET_INET6(curvnet);
 
 	if (ln->ln_ntick > 0) {
 		if (ln->ln_ntick > INT_MAX) {
@@ -595,7 +591,6 @@ void
 nd6_timer(void *arg)
 {
 	CURVNET_SET((struct vnet *) arg);
-	INIT_VNET_INET6(curvnet);
 	int s;
 	struct nd_defrouter *dr;
 	struct nd_prefix *pr;
@@ -794,7 +789,6 @@ regen_tmpaddr(struct in6_ifaddr *ia6)
 void
 nd6_purge(struct ifnet *ifp)
 {
-	INIT_VNET_INET6(ifp->if_vnet);
 	struct nd_defrouter *dr, *ndr;
 	struct nd_prefix *pr, *npr;
 
@@ -908,7 +902,6 @@ nd6_lookup(struct in6_addr *addr6, int flags, struct ifnet *ifp)
 static int
 nd6_is_new_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
 {
-	INIT_VNET_INET6(ifp->if_vnet);
 	struct nd_prefix *pr;
 	struct ifaddr *dstaddr;
 
@@ -1017,7 +1010,6 @@ nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp)
 static struct llentry *
 nd6_free(struct llentry *ln, int gc)
 {
-	INIT_VNET_INET6(curvnet);
         struct llentry *next;
 	struct nd_defrouter *dr;
 	struct ifnet *ifp=NULL;
@@ -1124,7 +1116,6 @@ nd6_free(struct llentry *ln, int gc)
 void
 nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force)
 {
-	INIT_VNET_INET6(curvnet);
 	struct llentry *ln;
 	struct ifnet *ifp;
 
@@ -1165,7 +1156,6 @@ done:
 int
 nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
 {
-	INIT_VNET_INET6(ifp->if_vnet);
 	struct in6_drlist *drl = (struct in6_drlist *)data;
 	struct in6_oprlist *oprl = (struct in6_oprlist *)data;
 	struct in6_ndireq *ndi = (struct in6_ndireq *)data;
@@ -1406,7 +1396,6 @@ struct llentry *
 nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr,
     int lladdrlen, int type, int code)
 {
-	INIT_VNET_INET6(curvnet);
 	struct llentry *ln = NULL;
 	int is_newentry;
 	int do_update;
@@ -1669,8 +1658,6 @@ static void
 nd6_slowtimo(void *arg)
 {
 	CURVNET_SET((struct vnet *) arg);
-	INIT_VNET_NET((struct vnet *) arg);
-	INIT_VNET_INET6((struct vnet *) arg);
 	struct nd_ifinfo *nd6if;
 	struct ifnet *ifp;
 
@@ -1720,7 +1707,6 @@ nd6_output_lle(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m0,
     struct sockaddr_in6 *dst, struct rtentry *rt0, struct llentry *lle,
 	struct mbuf **chain)
 {
-	INIT_VNET_INET6(curvnet);
 	struct mbuf *m = m0;
 	struct llentry *ln = lle;
 	int error = 0;
@@ -2105,13 +2091,12 @@ SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist,
 	CTLFLAG_RD, nd6_sysctl_drlist, "");
 SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist,
 	CTLFLAG_RD, nd6_sysctl_prlist, "");
-SYSCTL_V_INT(V_NET, vnet_inet6, _net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN,
-	nd6_maxqueuelen, CTLFLAG_RW, nd6_maxqueuelen, 1, "");
+SYSCTL_VNET_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen,
+	CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, "");
 
 static int
 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
 {
-	INIT_VNET_INET6(curvnet);
 	int error;
 	char buf[1024] __aligned(4);
 	struct in6_defrouter *d, *de;
@@ -2152,7 +2137,6 @@ nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
 static int
 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
 {
-	INIT_VNET_INET6(curvnet);
 	int error;
 	char buf[1024] __aligned(4);
 	struct in6_prefix *p, *pe;