From b90e3102ae22c0d68582e20f73faec5c72f229eb Mon Sep 17 00:00:00 2001
From: yasuoka <yasuoka@openbsd.org>
Date: Sat, 12 Jul 2014 21:06:34 +0000
Subject: [PATCH] Resize the pcb hashtable automatically.  The table size will
 be doubled when the number of the hash entries reaches 75% of the table size.

ok dlg henning, 'commit in' claudio
---
 sys/netinet/in_pcb.c     | 44 +++++++++++++++++++++++++++++++++++++++-
 sys/netinet/in_pcb.h     |  3 ++-
 sys/netinet/tcp_subr.c   |  9 ++++----
 sys/netinet/udp_usrreq.c |  9 ++++----
 4 files changed, 53 insertions(+), 12 deletions(-)

diff --git a/sys/netinet/in_pcb.c b/sys/netinet/in_pcb.c
index 6bc1601b983..24305d94441 100644
--- a/sys/netinet/in_pcb.c
+++ b/sys/netinet/in_pcb.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in_pcb.c,v 1.156 2014/06/04 13:45:47 mpi Exp $	*/
+/*	$OpenBSD: in_pcb.c,v 1.157 2014/07/12 21:06:34 yasuoka Exp $	*/
 /*	$NetBSD: in_pcb.c,v 1.25 1996/02/13 23:41:53 christos Exp $	*/
 
 /*
@@ -118,6 +118,10 @@ struct baddynamicports baddynamicports;
 struct pool inpcb_pool;
 int inpcb_pool_initialized = 0;
 
+int in_pcbresize (struct inpcbtable *, int);
+
+#define	INPCBHASH_LOADFACTOR(_x)	(((_x) * 3) / 4)
+
 #define	INPCBHASH(table, faddr, fport, laddr, lport, rdom) \
 	&(table)->inpt_hashtbl[(ntohl((faddr)->s_addr) + \
 	ntohs((fport)) + ntohs((lport)) + (rdom)) & (table->inpt_hash)]
@@ -144,6 +148,7 @@ in_pcbinit(struct inpcbtable *table, int hashsize)
 	if (table->inpt_lhashtbl == NULL)
 		panic("in_pcbinit: hashinit failed for lport");
 	table->inpt_lastport = 0;
+	table->inpt_count = 0;
 }
 
 /*
@@ -191,6 +196,9 @@ in_pcballoc(struct socket *so, struct inpcbtable *table)
 	inp->inp_seclevel[SL_IPCOMP] = IPSEC_IPCOMP_LEVEL_DEFAULT;
 	inp->inp_rtableid = curproc->p_p->ps_rtableid;
 	s = splnet();
+	if (table->inpt_hash != 0 &&
+	    table->inpt_count++ > INPCBHASH_LOADFACTOR(table->inpt_hash))
+		(void)in_pcbresize(table, (table->inpt_hash + 1) * 2);
 	TAILQ_INSERT_HEAD(&table->inpt_queue, inp, inp_queue);
 	LIST_INSERT_HEAD(INPCBLHASH(table, inp->inp_lport,
 	    inp->inp_rtableid), inp, inp_lhash);
@@ -502,6 +510,7 @@ in_pcbdetach(struct inpcb *inp)
 	LIST_REMOVE(inp, inp_lhash);
 	LIST_REMOVE(inp, inp_hash);
 	TAILQ_REMOVE(&inp->inp_table->inpt_queue, inp, inp_queue);
+	inp->inp_table->inpt_count--;
 	splx(s);
 	pool_put(&inpcb_pool, inp);
 }
@@ -880,6 +889,39 @@ in_pcbrehash(struct inpcb *inp)
 	splx(s);
 }
 
+int
+in_pcbresize(struct inpcbtable *table, int hashsize)
+{
+	u_long nhash, nlhash;
+	void *nhashtbl, *nlhashtbl, *ohashtbl, *olhashtbl;
+	struct inpcb *inp0, *inp1;
+
+	ohashtbl = table->inpt_hashtbl;
+	olhashtbl = table->inpt_lhashtbl;
+
+	nhashtbl = hashinit(hashsize, M_PCB, M_NOWAIT, &nhash);
+	nlhashtbl = hashinit(hashsize, M_PCB, M_NOWAIT, &nlhash);
+	if (nhashtbl == NULL || nlhashtbl == NULL) {
+		if (nhashtbl != NULL)
+			free(nhashtbl, M_PCB, 0);
+		if (nlhashtbl != NULL)
+			free(nlhashtbl, M_PCB, 0);
+		return (ENOBUFS);
+	}
+	table->inpt_hashtbl = nhashtbl;
+	table->inpt_lhashtbl = nlhashtbl;
+	table->inpt_hash = nhash;
+	table->inpt_lhash = nlhash;
+
+	TAILQ_FOREACH_SAFE(inp0, &table->inpt_queue, inp_queue, inp1) {
+		in_pcbrehash(inp0);
+	}
+	free(ohashtbl, M_PCB, 0);
+	free(olhashtbl, M_PCB, 0);
+
+	return (0);
+}
+
 #ifdef DIAGNOSTIC
 int	in_pcbnotifymiss = 0;
 #endif
diff --git a/sys/netinet/in_pcb.h b/sys/netinet/in_pcb.h
index 0c27f51c397..4923eac1a6a 100644
--- a/sys/netinet/in_pcb.h
+++ b/sys/netinet/in_pcb.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in_pcb.h,v 1.85 2014/04/18 10:48:29 jca Exp $	*/
+/*	$OpenBSD: in_pcb.h,v 1.86 2014/07/12 21:06:34 yasuoka Exp $	*/
 /*	$NetBSD: in_pcb.h,v 1.14 1996/02/13 23:42:00 christos Exp $	*/
 
 /*
@@ -158,6 +158,7 @@ struct inpcbtable {
 	LIST_HEAD(inpcbhead, inpcb) *inpt_hashtbl, *inpt_lhashtbl;
 	u_long	  inpt_hash, inpt_lhash;
 	u_int16_t inpt_lastport;
+	int	  inpt_count;
 };
 
 /* flags in inp_flags: */
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index 74d8d7264c9..72ea22b354c 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tcp_subr.c,v 1.130 2014/07/12 18:44:23 tedu Exp $	*/
+/*	$OpenBSD: tcp_subr.c,v 1.131 2014/07/12 21:06:34 yasuoka Exp $	*/
 /*	$NetBSD: tcp_subr.c,v 1.22 1996/02/13 23:44:00 christos Exp $	*/
 
 /*
@@ -118,10 +118,9 @@ int	tcp_do_rfc3390 = 2;	/* Increase TCP's Initial Window to 10*mss */
 
 u_int32_t	tcp_now = 1;
 
-#ifndef TCBHASHSIZE
-#define	TCBHASHSIZE	128
+#ifndef TCB_INITIAL_HASH_SIZE
+#define	TCB_INITIAL_HASH_SIZE	128
 #endif
-int	tcbhashsize = TCBHASHSIZE;
 
 /* syn hash parameters */
 #define	TCP_SYN_HASH_SIZE	293
@@ -162,7 +161,7 @@ tcp_init()
 	    NULL);
 	pool_sethardlimit(&sackhl_pool, tcp_sackhole_limit, NULL, 0);
 #endif /* TCP_SACK */
-	in_pcbinit(&tcbtable, tcbhashsize);
+	in_pcbinit(&tcbtable, TCB_INITIAL_HASH_SIZE);
 
 #ifdef INET6
 	/*
diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index e553b4ac5ce..162f7be93f1 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: udp_usrreq.c,v 1.187 2014/07/11 13:15:34 bluhm Exp $	*/
+/*	$OpenBSD: udp_usrreq.c,v 1.188 2014/07/12 21:06:34 yasuoka Exp $	*/
 /*	$NetBSD: udp_usrreq.c,v 1.28 1996/03/16 23:54:03 christos Exp $	*/
 
 /*
@@ -139,15 +139,14 @@ int	udp_output(struct inpcb *, struct mbuf *, struct mbuf *, struct mbuf *);
 void	udp_detach(struct inpcb *);
 void	udp_notify(struct inpcb *, int);
 
-#ifndef	UDBHASHSIZE
-#define	UDBHASHSIZE	128
+#ifndef	UDB_INITIAL_HASH_SIZE
+#define	UDB_INITIAL_HASH_SIZE	128
 #endif
-int	udbhashsize = UDBHASHSIZE;
 
 void
 udp_init()
 {
-	in_pcbinit(&udbtable, udbhashsize);
+	in_pcbinit(&udbtable, UDB_INITIAL_HASH_SIZE);
 }
 
 #ifdef INET6
-- 
2.20.1