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

@ -205,6 +205,7 @@ void inet_put_port(struct sock *sk);
void inet_hashinfo_init(struct inet_hashinfo *h);
int inet_ehash_insert(struct sock *sk, struct sock *osk);
void __inet_hash_nolisten(struct sock *sk, struct sock *osk);
void __inet_hash(struct sock *sk, struct sock *osk);
void inet_hash(struct sock *sk);