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linux/include/net/inet_common.h
Eric Dumazet 90ddc4f047 [NET]: move struct proto_ops to const
I noticed that some of 'struct proto_ops' used in the kernel may share
a cache line used by locks or other heavily modified data. (default
linker alignement is 32 bytes, and L1_CACHE_LINE is 64 or 128 at
least)

This patch makes sure a 'struct proto_ops' can be declared as const,
so that all cpus can share all parts of it without false sharing.

This is not mandatory : a driver can still use a read/write structure
if it needs to (and eventually a __read_mostly)

I made a global stubstitute to change all existing occurences to make
them const.

This should reduce the possibility of false sharing on SMP, and
speedup some socket system calls.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03 13:11:15 -08:00

49 lines
1.4 KiB
C

#ifndef _INET_COMMON_H
#define _INET_COMMON_H
extern const struct proto_ops inet_stream_ops;
extern const struct proto_ops inet_dgram_ops;
/*
* INET4 prototypes used by INET6
*/
struct msghdr;
struct sock;
struct sockaddr;
struct socket;
extern void inet_remove_sock(struct sock *sk1);
extern void inet_put_sock(unsigned short num,
struct sock *sk);
extern int inet_release(struct socket *sock);
extern int inet_stream_connect(struct socket *sock,
struct sockaddr * uaddr,
int addr_len, int flags);
extern int inet_dgram_connect(struct socket *sock,
struct sockaddr * uaddr,
int addr_len, int flags);
extern int inet_accept(struct socket *sock,
struct socket *newsock, int flags);
extern int inet_sendmsg(struct kiocb *iocb,
struct socket *sock,
struct msghdr *msg,
size_t size);
extern int inet_shutdown(struct socket *sock, int how);
extern unsigned int inet_poll(struct file * file, struct socket *sock, struct poll_table_struct *wait);
extern int inet_listen(struct socket *sock, int backlog);
extern void inet_sock_destruct(struct sock *sk);
extern int inet_bind(struct socket *sock,
struct sockaddr *uaddr, int addr_len);
extern int inet_getname(struct socket *sock,
struct sockaddr *uaddr,
int *uaddr_len, int peer);
extern int inet_ioctl(struct socket *sock,
unsigned int cmd, unsigned long arg);
#endif