Commit 304a1618 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo Committed by David S. Miller
Browse files

[INET]: Move the TCP ehash functions to include/net/inet_hashtables.h 



To be shared with DCCP (and others), this is the start of a series of patches
that will expose the already generic TCP hash table routines.

The few changes noticed when calling gcc -S before/after on a pentium4 were of
this type:

        movl    40(%esp), %edx
        cmpl    %esi, 472(%edx)
        je      .L168
-       pushl   $291
+       pushl   $272
        pushl   $.LC0
        pushl   $.LC1
        pushl   $.LC2

[acme@toy net-2.6.14]$ size net/ipv4/tcp_ipv4.before.o net/ipv4/tcp_ipv4.after.o
   text    data     bss     dec     hex filename
  17804     516     140   18460    481c net/ipv4/tcp_ipv4.before.o
  17804     516     140   18460    481c net/ipv4/tcp_ipv4.after.o

Holler if some weird architecture has issues with things like this 8)

Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0597f268

include/net/inet_hashtables.h

0 → 100644
+40 −0
Original line number Diff line number Diff line 
/*

 * INET		An implementation of the TCP/IP protocol suite for the LINUX

 *		operating system.  INET is implemented using the BSD Socket

 *		interface as the means of communication with the user level.

 *

 * Authors:	Lotsa people, from code originally in tcp

 *

 *	This program is free software; you can redistribute it and/or

 *      modify it under the terms of the GNU General Public License

 *      as published by the Free Software Foundation; either version

 *      2 of the License, or (at your option) any later version.

 */



#ifndef _INET_HASHTABLES_H

#define _INET_HASHTABLES_H



#include <linux/types.h>



static inline int inet_ehashfn(const __u32 laddr, const __u16 lport,

			       const __u32 faddr, const __u16 fport,

			       const int ehash_size)

{

	int h = (laddr ^ lport) ^ (faddr ^ fport);

	h ^= h >> 16;

	h ^= h >> 8;

	return h & (ehash_size - 1);

}



static inline int inet_sk_ehashfn(const struct sock *sk, const int ehash_size)

{

	const struct inet_sock *inet = inet_sk(sk);

	const __u32 laddr = inet->rcv_saddr;

	const __u16 lport = inet->num;

	const __u32 faddr = inet->daddr;

	const __u16 fport = inet->dport;



	return inet_ehashfn(laddr, lport, faddr, fport, ehash_size);

}



#endif /* _INET_HASHTABLES_H */

net/ipv4/tcp_ipv4.c

+5 −23
Original line number Diff line number Diff line
@@ -64,6 +64,7 @@ 
#include <linux/times.h>



#include <net/icmp.h>

#include <net/inet_hashtables.h>

#include <net/tcp.h>

#include <net/ipv6.h>

#include <net/inet_common.h>
@@ -104,26 +105,6 @@ struct tcp_hashinfo __cacheline_aligned tcp_hashinfo = { 
int sysctl_local_port_range[2] = { 1024, 4999 };

int tcp_port_rover = 1024 - 1;



static __inline__ int tcp_hashfn(__u32 laddr, __u16 lport,

				 __u32 faddr, __u16 fport)

{

	int h = (laddr ^ lport) ^ (faddr ^ fport);

	h ^= h >> 16;

	h ^= h >> 8;

	return h & (tcp_ehash_size - 1);

}



static __inline__ int tcp_sk_hashfn(struct sock *sk)

{

	struct inet_sock *inet = inet_sk(sk);

	__u32 laddr = inet->rcv_saddr;

	__u16 lport = inet->num;

	__u32 faddr = inet->daddr;

	__u16 fport = inet->dport;



	return tcp_hashfn(laddr, lport, faddr, fport);

}



/* Allocate and initialize a new TCP local port bind bucket.

 * The bindhash mutex for snum's hash chain must be held here.

 */
@@ -367,7 +348,8 @@ static __inline__ void __tcp_v4_hash(struct sock *sk, const int listen_possible) 
		lock = &tcp_lhash_lock;

		tcp_listen_wlock();

	} else {

		list = &tcp_ehash[(sk->sk_hashent = tcp_sk_hashfn(sk))].chain;

		sk->sk_hashent = inet_sk_ehashfn(sk, tcp_ehash_size);

		list = &tcp_ehash[sk->sk_hashent].chain;

		lock = &tcp_ehash[sk->sk_hashent].lock;

		write_lock(lock);

	}
@@ -500,7 +482,7 @@ static inline struct sock *__tcp_v4_lookup_established(u32 saddr, u16 sport, 
	/* Optimize here for direct hit, only listening connections can

	 * have wildcards anyways.

	 */

	int hash = tcp_hashfn(daddr, hnum, saddr, sport);

	const int hash = inet_ehashfn(daddr, hnum, saddr, sport, tcp_ehash_size);

	head = &tcp_ehash[hash];

	read_lock(&head->lock);

	sk_for_each(sk, node, &head->chain) {
@@ -563,7 +545,7 @@ static int __tcp_v4_check_established(struct sock *sk, __u16 lport, 
	int dif = sk->sk_bound_dev_if;

	TCP_V4_ADDR_COOKIE(acookie, saddr, daddr)

	__u32 ports = TCP_COMBINED_PORTS(inet->dport, lport);

	int hash = tcp_hashfn(daddr, lport, saddr, inet->dport);

	const int hash = inet_ehashfn(daddr, lport, saddr, inet->dport, tcp_ehash_size);

	struct tcp_ehash_bucket *head = &tcp_ehash[hash];

	struct sock *sk2;

	struct hlist_node *node;

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