quiche/recovery/congestion/bbr2/

per_transmit.rs

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use super::*;

use std::time::Instant;

// BBR2 Functions when trasmitting packets.
//
// 4.2.2.  Per-Transmit Steps
pub fn bbr2_on_transmit(
    r: &mut Congestion, bytes_in_flight: usize, now: Instant,
) {
    bbr2_handle_restart_from_idle(r, bytes_in_flight, now);
}

// 4.4.3.  Logic
fn bbr2_handle_restart_from_idle(
    r: &mut Congestion, bytes_in_flight: usize, now: Instant,
) {
    if bytes_in_flight == 0 && r.delivery_rate.app_limited() {
        r.bbr2_state.idle_restart = true;
        r.bbr2_state.extra_acked_interval_start = now;

        if per_ack::bbr2_is_in_a_probe_bw_state(r) {
            pacing::bbr2_set_pacing_rate_with_gain(r, 1.0);
        } else if r.bbr2_state.state == BBR2StateMachine::ProbeRTT {
            per_ack::bbr2_check_probe_rtt_done(r, now);
        }
    }
}