Destroy TCP UMA zones (empty or not) upon network stack teardown

to not leak them, otherwise making UMA/vmstat unhappy with every stoped vnet.
We will still leak pages (especially for zones marked NOFREE).

Reshuffle cleanup order in tcp_destroy() to get rid of what we can
easily free first.

Sponsored by:	ISPsystem
Reviewed by:	rwatson
MFC after:	5 days

sys/netinet/tcp_reass.c

@@ -132,6 +132,15 @@ tcp_reass_init(void)
 	    tcp_reass_zone_change, NULL, EVENTHANDLER_PRI_ANY);
 }
 
+#ifdef VIMAGE
+void
+tcp_reass_destroy(void)
+{
+
+	uma_zdestroy(V_tcp_reass_zone);
+}
+#endif
+
 int
 tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
 {

sys/netinet/tcp_subr.c

@@ -459,15 +459,21 @@ void
 tcp_destroy(void)
 {
 
-	tcp_tw_destroy();
+	tcp_reass_destroy();
 	tcp_hc_destroy();
 	syncache_destroy();
+	tcp_tw_destroy();
 
 	/* XXX check that hashes are empty! */
 	hashdestroy(V_tcbinfo.ipi_hashbase, M_PCB,
 	    V_tcbinfo.ipi_hashmask);
 	hashdestroy(V_tcbinfo.ipi_porthashbase, M_PCB,
 	    V_tcbinfo.ipi_porthashmask);
+
+	uma_zdestroy(V_sack_hole_zone);
+	uma_zdestroy(V_tcpcb_zone);
+	uma_zdestroy(V_tcbinfo.ipi_zone);
+
 	INP_INFO_LOCK_DESTROY(&V_tcbinfo);
 }
 #endif

sys/netinet/tcp_timewait.c

@@ -185,6 +185,8 @@ tcp_tw_destroy(void)
 	while((tw = TAILQ_FIRST(&V_twq_2msl)) != NULL)
 		tcp_twclose(tw, 0);
 	INP_INFO_WUNLOCK(&V_tcbinfo);
+
+	uma_zdestroy(V_tcptw_zone);
 }
 #endif
 

sys/netinet/tcp_var.h

@@ -657,6 +657,9 @@ char 	*tcp_log_addrs(struct in_conninfo *, struct tcphdr *, void *,
 	    const void *);
 int	 tcp_reass(struct tcpcb *, struct tcphdr *, int *, struct mbuf *);
 void	 tcp_reass_init(void);
+#ifdef VIMAGE
+void	 tcp_reass_destroy(void);
+#endif
 void	 tcp_input(struct mbuf *, int);
 u_long	 tcp_maxmtu(struct in_conninfo *, int *);
 u_long	 tcp_maxmtu6(struct in_conninfo *, int *);