path: root/net/ipv4/tcp_bbr.c
diff options
authorKevin Yang <yyd@google.com>2018-08-22 17:43:15 -0400
committerDavid S. Miller <davem@davemloft.net>2018-08-22 21:45:32 -0700
commit5490b32dce6932ea7ee8e3b2f76db2957c92af6e (patch)
treeb574deed86b5ef6c358e8531c02656ebcff8638d /net/ipv4/tcp_bbr.c
parenttcp_bbr: add bbr_check_probe_rtt_done() helper (diff)
tcp_bbr: in restart from idle, see if we should exit PROBE_RTT
This patch fix the case where BBR does not exit PROBE_RTT mode when it restarts from idle. When BBR restarts from idle and if BBR is in PROBE_RTT mode, BBR should check if it's time to exit PROBE_RTT. If yes, then BBR should exit PROBE_RTT mode and restore the cwnd to its full value. Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control") Signed-off-by: Kevin Yang <yyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_bbr.c')
1 files changed, 4 insertions, 0 deletions
diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c
index fd7bccf36a26..1d4bdd3b5e4d 100644
--- a/net/ipv4/tcp_bbr.c
+++ b/net/ipv4/tcp_bbr.c
@@ -174,6 +174,8 @@ static const u32 bbr_lt_bw_diff = 4000 / 8;
/* If we estimate we're policed, use lt_bw for this many round trips: */
static const u32 bbr_lt_bw_max_rtts = 48;
+static void bbr_check_probe_rtt_done(struct sock *sk);
/* Do we estimate that STARTUP filled the pipe? */
static bool bbr_full_bw_reached(const struct sock *sk)
@@ -308,6 +310,8 @@ static void bbr_cwnd_event(struct sock *sk, enum tcp_ca_event event)
if (bbr->mode == BBR_PROBE_BW)
bbr_set_pacing_rate(sk, bbr_bw(sk), BBR_UNIT);
+ else if (bbr->mode == BBR_PROBE_RTT)
+ bbr_check_probe_rtt_done(sk);