tcp: bind() use stronger condition for bind_conflict
We must try harder to get unique (addr, port) pairs when
doing port autoselection for sockets with SO_REUSEADDR
option set.
We achieve this by adding a relaxation parameter to
inet_csk_bind_conflict. When 'relax' parameter is off
we return a conflict whenever the current searched
pair (addr, port) is not unique.
This tries to address the problems reported in patch:
8d238b25b1ec22a73b1c2206f111df2faaff8285
Revert "tcp: bind() fix when many ports are bound"
Tests where ran for creating and binding(0) many sockets
on 100 IPs. The results are, on average:
* 60000 sockets, 600 ports / IP:
* 0.210 s, 620 (IP, port) duplicates without patch
* 0.219 s, no duplicates with patch
* 100000 sockets, 1000 ports / IP:
* 0.371 s, 1720 duplicates without patch
* 0.373 s, no duplicates with patch
* 200000 sockets, 2000 ports / IP:
* 0.766 s, 6900 duplicates without patch
* 0.768 s, no duplicates with patch
* 500000 sockets, 5000 ports / IP:
* 2.227 s, 41500 duplicates without patch
* 2.284 s, no duplicates with patch
Signed-off-by: Alex Copot <alex.mihai.c@gmail.com>
Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index dbf9aab..46c9e2c 100644
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -60,7 +60,7 @@
#endif
void (*addr2sockaddr)(struct sock *sk, struct sockaddr *);
int (*bind_conflict)(const struct sock *sk,
- const struct inet_bind_bucket *tb);
+ const struct inet_bind_bucket *tb, bool relax);
};
/** inet_connection_sock - INET connection oriented sock
@@ -245,7 +245,7 @@
const __be32 raddr,
const __be32 laddr);
extern int inet_csk_bind_conflict(const struct sock *sk,
- const struct inet_bind_bucket *tb);
+ const struct inet_bind_bucket *tb, bool relax);
extern int inet_csk_get_port(struct sock *sk, unsigned short snum);
extern struct dst_entry* inet_csk_route_req(struct sock *sk,