diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-07-20 05:45:50 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-07-20 10:59:41 -0700 |
| commit | 6f458dfb409272082c9bfa412f77ff2fc21c626f (patch) | |
| tree | 7475cd12eb01023b9852cbc957080b9aa7cfdc64 /include/net | |
| parent | 9dc274151a548ffd215caecec5a8872db8799447 (diff) | |
tcp: improve latencies of timer triggered events
Modern TCP stack highly depends on tcp_write_timer() having a small
latency, but current implementation doesn't exactly meet the
expectations.
When a timer fires but finds the socket is owned by the user, it rearms
itself for an additional delay hoping next run will be more
successful.
tcp_write_timer() for example uses a 50ms delay for next try, and it
defeats many attempts to get predictable TCP behavior in term of
latencies.
Use the recently introduced tcp_release_cb(), so that the user owning
the socket will call various handlers right before socket release.
This will permit us to post a followup patch to address the
tcp_tso_should_defer() syndrome (some deferred packets have to wait
RTO timer to be transmitted, while cwnd should allow us to send them
sooner)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: John Heffner <johnwheffner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/tcp.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index bc7c134ec05..e19124b84cd 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -350,6 +350,8 @@ extern int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, extern int tcp_sendpage(struct sock *sk, struct page *page, int offset, size_t size, int flags); extern void tcp_release_cb(struct sock *sk); +extern void tcp_write_timer_handler(struct sock *sk); +extern void tcp_delack_timer_handler(struct sock *sk); extern int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg); extern int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, const struct tcphdr *th, unsigned int len); |