diff options
| author | Stephen Hemminger <shemminger@linux-foundation.org> | 2007-07-25 23:49:34 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-07-31 02:27:57 -0700 |
| commit | 30cfd0baf0a0c4329fff1ef4b622919297969ec8 (patch) | |
| tree | 945a72f636ced1b443d894495704237e4cb7816d /net/ipv4/tcp_illinois.c | |
| parent | 6a302358d87fedaf7bda12b8e909265ebf1ce674 (diff) | |
| download | linux-30cfd0baf0a0c4329fff1ef4b622919297969ec8.tar.bz2 | |
[TCP]: congestion control API pass RTT in microseconds
This patch changes the API for the callback that is done after an ACK is
received. It solves a couple of issues:
* Some congestion controls want higher resolution value of RTT
(controlled by TCP_CONG_RTT_SAMPLE flag). These don't really want a ktime, but
all compute a RTT in microseconds.
* Other congestion control could use RTT at jiffies resolution.
To keep API consistent the units should be the same for both cases, just the
resolution should change.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_illinois.c')
| -rw-r--r-- | net/ipv4/tcp_illinois.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/net/ipv4/tcp_illinois.c b/net/ipv4/tcp_illinois.c index cc5de6f69d46..64f1cbaf96e8 100644 --- a/net/ipv4/tcp_illinois.c +++ b/net/ipv4/tcp_illinois.c @@ -83,18 +83,16 @@ static void tcp_illinois_init(struct sock *sk) } /* Measure RTT for each ack. */ -static void tcp_illinois_acked(struct sock *sk, u32 pkts_acked, ktime_t last) +static void tcp_illinois_acked(struct sock *sk, u32 pkts_acked, s32 rtt) { struct illinois *ca = inet_csk_ca(sk); - u32 rtt; ca->acked = pkts_acked; - if (ktime_equal(last, net_invalid_timestamp())) + /* dup ack, no rtt sample */ + if (rtt < 0) return; - rtt = ktime_to_us(net_timedelta(last)); - /* ignore bogus values, this prevents wraparound in alpha math */ if (rtt > RTT_MAX) rtt = RTT_MAX; |