gfe-relnote: (n/a) Refactor Bbr2ProbeBwMode::OnCongestionEvent such that it only has one return point. No behavior change, not protected.
This makes it easier to do things when bbr2 switches phases.
PiperOrigin-RevId: 282350548
Change-Id: Ic94ccbf2328ba0c791a8162b096511889e317024
diff --git a/quic/core/congestion_control/bbr2_probe_bw.cc b/quic/core/congestion_control/bbr2_probe_bw.cc
index 887d553..7f9cd1f 100644
--- a/quic/core/congestion_control/bbr2_probe_bw.cc
+++ b/quic/core/congestion_control/bbr2_probe_bw.cc
@@ -48,6 +48,8 @@
}
}
+ bool switch_to_probe_rtt = false;
+
if (cycle_.phase == CyclePhase::PROBE_UP) {
UpdateProbeUp(prior_in_flight, congestion_event);
} else if (cycle_.phase == CyclePhase::PROBE_DOWN) {
@@ -55,7 +57,7 @@
// Maybe transition to PROBE_RTT at the end of this cycle.
if (cycle_.phase != CyclePhase::PROBE_DOWN &&
model_->MaybeExpireMinRtt(congestion_event)) {
- return Bbr2Mode::PROBE_RTT;
+ switch_to_probe_rtt = true;
}
} else if (cycle_.phase == CyclePhase::PROBE_CRUISE) {
UpdateProbeCruise(congestion_event);
@@ -63,10 +65,14 @@
UpdateProbeRefill(congestion_event);
}
- model_->set_pacing_gain(PacingGainForPhase(cycle_.phase));
- model_->set_cwnd_gain(Params().probe_bw_cwnd_gain);
+ // Do not need to set the gains if switching to PROBE_RTT, they will be set
+ // when Bbr2ProbeRttMode::Enter is called.
+ if (!switch_to_probe_rtt) {
+ model_->set_pacing_gain(PacingGainForPhase(cycle_.phase));
+ model_->set_cwnd_gain(Params().probe_bw_cwnd_gain);
+ }
- return Bbr2Mode::PROBE_BW;
+ return switch_to_probe_rtt ? Bbr2Mode::PROBE_RTT : Bbr2Mode::PROBE_BW;
}
Limits<QuicByteCount> Bbr2ProbeBwMode::GetCwndLimits() const {
