path: root/net/ipv4/tcp_illinois.c
diff options
authorStephen Hemminger <shemminger@linux-foundation.org>2007-07-25 23:49:34 -0700
committerDavid S. Miller <davem@sunset.davemloft.net>2007-07-31 02:27:57 -0700
commit30cfd0baf0a0c4329fff1ef4b622919297969ec8 (patch)
tree945a72f636ced1b443d894495704237e4cb7816d /net/ipv4/tcp_illinois.c
parentMerge master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6.23 (diff)
[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')
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)
- rtt = ktime_to_us(net_timedelta(last));
/* ignore bogus values, this prevents wraparound in alpha math */
if (rtt > RTT_MAX)
rtt = RTT_MAX;