linux/net/netlink/af_netlink.h
Ying Xue c5adde9468 netlink: eliminate nl_sk_hash_lock
As rhashtable_lookup_compare_insert() can guarantee the process
of search and insertion is atomic, it's safe to eliminate the
nl_sk_hash_lock. After this, object insertion or removal will
be protected with per bucket lock on write side while object
lookup is guarded with rcu read lock on read side.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Thomas Graf <tgraf@suug.ch>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-13 14:01:00 -05:00

79 lines
1.8 KiB
C

#ifndef _AF_NETLINK_H
#define _AF_NETLINK_H
#include <linux/rhashtable.h>
#include <net/sock.h>
#define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
#define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long))
struct netlink_ring {
void **pg_vec;
unsigned int head;
unsigned int frames_per_block;
unsigned int frame_size;
unsigned int frame_max;
unsigned int pg_vec_order;
unsigned int pg_vec_pages;
unsigned int pg_vec_len;
atomic_t pending;
};
struct netlink_sock {
/* struct sock has to be the first member of netlink_sock */
struct sock sk;
u32 portid;
u32 dst_portid;
u32 dst_group;
u32 flags;
u32 subscriptions;
u32 ngroups;
unsigned long *groups;
unsigned long state;
size_t max_recvmsg_len;
wait_queue_head_t wait;
bool cb_running;
struct netlink_callback cb;
struct mutex *cb_mutex;
struct mutex cb_def_mutex;
void (*netlink_rcv)(struct sk_buff *skb);
int (*netlink_bind)(struct net *net, int group);
void (*netlink_unbind)(struct net *net, int group);
struct module *module;
#ifdef CONFIG_NETLINK_MMAP
struct mutex pg_vec_lock;
struct netlink_ring rx_ring;
struct netlink_ring tx_ring;
atomic_t mapped;
#endif /* CONFIG_NETLINK_MMAP */
struct rhash_head node;
struct rcu_head rcu;
};
static inline struct netlink_sock *nlk_sk(struct sock *sk)
{
return container_of(sk, struct netlink_sock, sk);
}
struct netlink_table {
struct rhashtable hash;
struct hlist_head mc_list;
struct listeners __rcu *listeners;
unsigned int flags;
unsigned int groups;
struct mutex *cb_mutex;
struct module *module;
int (*bind)(struct net *net, int group);
void (*unbind)(struct net *net, int group);
bool (*compare)(struct net *net, struct sock *sock);
int registered;
};
extern struct netlink_table *nl_table;
extern rwlock_t nl_table_lock;
#endif