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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2009-11-08 10:17:58 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-11-08 20:53:06 -0800 |
| commit | 512615b6b843ff3ff5ad583f34c39b3f302f5f26 (patch) | |
| tree | 7420705a314bc691bc478225148935dc67f71904 /include/net/udp.h | |
| parent | d4cada4ae1c012815f95fa507eb86a0ae9d607d7 (diff) | |
| download | lwn-512615b6b843ff3ff5ad583f34c39b3f302f5f26.tar.gz lwn-512615b6b843ff3ff5ad583f34c39b3f302f5f26.zip | |
udp: secondary hash on (local port, local address)
Extends udp_table to contain a secondary hash table.
socket anchor for this second hash is free, because UDP
doesnt use skc_bind_node : We define an union to hold
both skc_bind_node & a new hlist_nulls_node udp_portaddr_node
udp_lib_get_port() inserts sockets into second hash chain
(additional cost of one atomic op)
udp_lib_unhash() deletes socket from second hash chain
(additional cost of one atomic op)
Note : No spinlock lockdep annotation is needed, because
lock for the secondary hash chain is always get after
lock for primary hash chain.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/udp.h')
| -rw-r--r-- | include/net/udp.h | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/include/net/udp.h b/include/net/udp.h index 9167281e47dc..af41850f742a 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -63,10 +63,19 @@ struct udp_hslot { spinlock_t lock; } __attribute__((aligned(2 * sizeof(long)))); +/** + * struct udp_table - UDP table + * + * @hash: hash table, sockets are hashed on (local port) + * @hash2: hash table, sockets are hashed on (local port, local address) + * @mask: number of slots in hash tables, minus 1 + * @log: log2(number of slots in hash table) + */ struct udp_table { struct udp_hslot *hash; - unsigned int mask; - unsigned int log; + struct udp_hslot *hash2; + unsigned int mask; + unsigned int log; }; extern struct udp_table udp_table; extern void udp_table_init(struct udp_table *, const char *); @@ -75,6 +84,15 @@ static inline struct udp_hslot *udp_hashslot(struct udp_table *table, { return &table->hash[udp_hashfn(net, num, table->mask)]; } +/* + * For secondary hash, net_hash_mix() is performed before calling + * udp_hashslot2(), this explains difference with udp_hashslot() + */ +static inline struct udp_hslot *udp_hashslot2(struct udp_table *table, + unsigned int hash) +{ + return &table->hash2[hash & table->mask]; +} /* Note: this must match 'valbool' in sock_setsockopt */ #define UDP_CSUM_NOXMIT 1 |