mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 08:02:07 +00:00
e0386005ff
Use cmpxchg() to get rid of spinlocks in inet_add_protocol() and friends. inet_protos[] & inet6_protos[] are moved to read_mostly section Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
53 lines
1.5 KiB
C
53 lines
1.5 KiB
C
/*
|
|
* 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.
|
|
*
|
|
* PF_INET6 protocol dispatch tables.
|
|
*
|
|
* Authors: Pedro Roque <roque@di.fc.ul.pt>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
/*
|
|
* Changes:
|
|
*
|
|
* Vince Laviano (vince@cs.stanford.edu) 16 May 2001
|
|
* - Removed unused variable 'inet6_protocol_base'
|
|
* - Modified inet6_del_protocol() to correctly maintain copy bit.
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/spinlock.h>
|
|
#include <net/protocol.h>
|
|
|
|
const struct inet6_protocol *inet6_protos[MAX_INET_PROTOS] __read_mostly;
|
|
|
|
int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char protocol)
|
|
{
|
|
int hash = protocol & (MAX_INET_PROTOS - 1);
|
|
|
|
return !cmpxchg(&inet6_protos[hash], NULL, prot) ? 0 : -1;
|
|
}
|
|
EXPORT_SYMBOL(inet6_add_protocol);
|
|
|
|
/*
|
|
* Remove a protocol from the hash tables.
|
|
*/
|
|
|
|
int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char protocol)
|
|
{
|
|
int ret, hash = protocol & (MAX_INET_PROTOS - 1);
|
|
|
|
ret = (cmpxchg(&inet6_protos[hash], prot, NULL) == prot) ? 0 : -1;
|
|
|
|
synchronize_net();
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(inet6_del_protocol);
|