lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[TCP]: TCP_DEFER_ACCEPT updates - process as established

Browse Source 
Change TCP_DEFER_ACCEPT implementation so that it transitions a
connection to ESTABLISHED after handshake is complete instead of
leaving it in SYN-RECV until some data arrvies. Place connection in
accept queue when first data packet arrives from slow path.

Benefits:
  - established connection is now reset if it never makes it
   to the accept queue

 - diagnostic state of established matches with the packet traces
   showing completed handshake

 - TCP_DEFER_ACCEPT timeouts are expressed in seconds and can now be
   enforced with reasonable accuracy instead of rounding up to next
   exponential back-off of syn-ack retry.

Signed-off-by: Patrick McManus <mcmanus@ducksong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McManus
2008-03-21 16:33:01 -07:00
committed by David S. Miller
parent e4c7884028
commit ec3c0982a2
9 changed files with 99 additions and 33 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
net/ipv4/tcp.c
View File

@@ -2105,15 +2105,12 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
break;
case TCP_DEFER_ACCEPT:
icsk->icsk_accept_queue.rskq_defer_accept = 0;
if (val > 0) {
/* Translate value in seconds to number of
* retransmits */
while (icsk->icsk_accept_queue.rskq_defer_accept < 32 &&
val > ((TCP_TIMEOUT_INIT / HZ) <<
icsk->icsk_accept_queue.rskq_defer_accept))
icsk->icsk_accept_queue.rskq_defer_accept++;
icsk->icsk_accept_queue.rskq_defer_accept++;
if (val < 0) {
err = -EINVAL;
} else {
if (val > MAX_TCP_ACCEPT_DEFERRED)
val = MAX_TCP_ACCEPT_DEFERRED;
icsk->icsk_accept_queue.rskq_defer_accept = val;
}
break;
@@ -2295,8 +2292,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
val = (val ? : sysctl_tcp_fin_timeout) / HZ;
break;
case TCP_DEFER_ACCEPT:
val = !icsk->icsk_accept_queue.rskq_defer_accept ? 0 :
((TCP_TIMEOUT_INIT / HZ) << (icsk->icsk_accept_queue.rskq_defer_accept - 1));
val = icsk->icsk_accept_queue.rskq_defer_accept;
break;
case TCP_WINDOW_CLAMP:
val = tp->window_clamp;