gfe-relnote: In QUIC, making sure there are always enough credits for non-loss retransmission. Protected by gfe2_reloadable_flag_quic_grant_enough_credits.
PiperOrigin-RevId: 269791493
Change-Id: I9e841bdc1110ae7600415b428e2371573a8a8687
diff --git a/quic/core/quic_sent_packet_manager.cc b/quic/core/quic_sent_packet_manager.cc
index ee7bb34..8731306 100644
--- a/quic/core/quic_sent_packet_manager.cc
+++ b/quic/core/quic_sent_packet_manager.cc
@@ -67,6 +67,31 @@
(unacked_packets_.perspective() == Perspective::IS_SERVER ? "Server: " \
: "Client: ")
+QuicSentPacketManager::ScopedCreditGrantor::ScopedCreditGrantor(
+ QuicSentPacketManager* manager)
+ : manager_(manager), credits_granted_(false) {
+ if (!GetQuicReloadableFlag(quic_grant_enough_credits)) {
+ return;
+ }
+ QUIC_RELOADABLE_FLAG_COUNT(quic_grant_enough_credits);
+ if (manager_->pending_timer_transmission_count() > 1) {
+ // There are enough credits to retransmit one packet.
+ return;
+ }
+ // Grant 2 credits because a single packet can be transmitted as 2 (if packet
+ // number length changes).
+ manager_->set_pending_timer_transmission_count(2);
+ credits_granted_ = true;
+}
+
+QuicSentPacketManager::ScopedCreditGrantor::~ScopedCreditGrantor() {
+ if (!credits_granted_) {
+ // Do not clear credits if there is no credit granted.
+ return;
+ }
+ manager_->set_pending_timer_transmission_count(0);
+}
+
QuicSentPacketManager::QuicSentPacketManager(
Perspective perspective,
const QuicClock* clock,
@@ -525,6 +550,7 @@
// applications may want to use higher priority stream data for bandwidth
// probing, and some applications want to consider RTO is an indication of
// loss, etc.
+ ScopedCreditGrantor grantor(this);
unacked_packets_.RetransmitFrames(*transmission_info, transmission_type);
return;
}
