tcp/dccp: install syn_recv requests into ehash table

In this patch, we insert request sockets into TCP/DCCP
regular ehash table (where ESTABLISHED and TIMEWAIT sockets
are) instead of using the per listener hash table.

ACK packets find SYN_RECV pseudo sockets without having
to find and lock the listener.

In nominal conditions, this halves pressure on listener lock.

Note that this will allow for SO_REUSEPORT refinements,
so that we can select a listener using cpu/numa affinities instead
of the prior 'consistent hash', since only SYN packets will
apply this selection logic.

We will shrink listen_sock in the following patch to ease
code review.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ying Cai <ycai@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
2015-10-02 11:43:32 -07:00
committed by David S. Miller
parent 2feda34192
commit 079096f103
15 changed files with 163 additions and 504 deletions

View File

@@ -1618,7 +1618,6 @@ static inline bool tcp_stream_is_thin(struct tcp_sock *tp)
/* /proc */
enum tcp_seq_states {
TCP_SEQ_STATE_LISTENING,
TCP_SEQ_STATE_OPENREQ,
TCP_SEQ_STATE_ESTABLISHED,
};
@@ -1717,8 +1716,6 @@ struct tcp_request_sock_ops {
int (*send_synack)(const struct sock *sk, struct dst_entry *dst,
struct flowi *fl, struct request_sock *req,
u16 queue_mapping, struct tcp_fastopen_cookie *foc);
void (*queue_hash_add)(struct sock *sk, struct request_sock *req,
const unsigned long timeout);
};
#ifdef CONFIG_SYN_COOKIES