MINOR: quic: Add correct ack delay values to ACK frames
A ->time_received new member is added to quic_rx_packet to store the time the
packet are received. ->largest_time_received is added the the packet number
space structure to store this timestamp for the packet with a new largest
packet number to be acknowledged. QUIC_FL_PKTNS_NEW_LARGEST_PN new flag is
added to mark a packet number space as having to acknowledged a packet wih a
new largest packet number. In this case, the packet number space ack delay
must be recalculated.
Add quic_compute_ack_delay_us() function to compute the ack delay from the value
of the time a packet was received. Used only when a packet with a new largest
packet number.
diff --git a/include/haproxy/xprt_quic-t.h b/include/haproxy/xprt_quic-t.h
index 504294f..4db01fc 100644
--- a/include/haproxy/xprt_quic-t.h
+++ b/include/haproxy/xprt_quic-t.h
@@ -395,6 +395,10 @@
#define QUIC_FL_PKTNS_ACK_REQUIRED (1UL << 1)
/* Flag the packet number space as needing probing */
#define QUIC_FL_PKTNS_PROBE_NEEDED (1UL << 2)
+/* Flag the packet number space as having received a packet with a new largest
+ * packet number, to be acknowledege
+ */
+#define QUIC_FL_PKTNS_NEW_LARGEST_PN (1UL << 3)
/* The maximum number of dgrams which may be sent upon PTO expirations. */
#define QUIC_MAX_NB_PTO_DGRAMS 2
@@ -416,6 +420,8 @@
unsigned int pto_probe;
/* In flight bytes for this packet number space. */
size_t in_flight;
+ /* The acknowledgement delay of the packet with the largest packet number */
+ uint64_t ack_delay;
} tx;
struct {
/* Largest packet number */
@@ -424,6 +430,8 @@
int64_t largest_acked_pn;
struct quic_arngs arngs;
unsigned int nb_aepkts_since_last_ack;
+ /* The time the packet with the largest packet number was received */
+ uint64_t largest_time_received;
} rx;
unsigned int flags;
};
@@ -483,6 +491,7 @@
/* Source address of this packet. */
struct sockaddr_storage saddr;
unsigned int flags;
+ unsigned int time_received;
};
/* QUIC datagram handler */
diff --git a/include/haproxy/xprt_quic.h b/include/haproxy/xprt_quic.h
index 6457fa4..2c98ed6 100644
--- a/include/haproxy/xprt_quic.h
+++ b/include/haproxy/xprt_quic.h
@@ -477,6 +477,15 @@
return (ack_frm->ack_delay << conn->tx.params.ack_delay_exponent) / 1000;
}
+/* Returns the <ack_delay> field value in microsecond to be set in an ACK frame
+ * depending on the time the packet with a new largest packet number was received.
+ */
+static inline uint64_t quic_compute_ack_delay_us(unsigned int time_received,
+ struct quic_conn *conn)
+{
+ return ((now_ms - time_received) * 1000) >> conn->tx.params.ack_delay_exponent;
+}
+
/* Initialize <dst> transport parameters with default values (when absent)
* from <quic_dflt_trasports_params>.
* Never fails.
@@ -981,6 +990,7 @@
pktns->tx.time_of_last_eliciting = 0;
pktns->tx.loss_time = TICK_ETERNITY;
pktns->tx.in_flight = 0;
+ pktns->tx.ack_delay = 0;
pktns->rx.largest_pn = -1;
pktns->rx.largest_acked_pn = -1;
@@ -988,6 +998,7 @@
pktns->rx.arngs.sz = 0;
pktns->rx.arngs.enc_sz = 0;
pktns->rx.nb_aepkts_since_last_ack = 0;
+ pktns->rx.largest_time_received = 0;
pktns->flags = 0;
}
diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index ffdbe77..66c3555 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -3621,6 +3621,7 @@
{
struct eb64_node *node;
int64_t largest_pn = -1;
+ unsigned int largest_pn_time_received = 0;
struct quic_conn *qc = ctx->qc;
struct quic_enc_level *qel = cur_el;
@@ -3657,8 +3658,10 @@
qel->pktns->rx.nb_aepkts_since_last_ack++;
qc_idle_timer_rearm(qc, 1);
}
- if (pkt->pn > largest_pn)
+ if (pkt->pn > largest_pn) {
largest_pn = pkt->pn;
+ largest_pn_time_received = pkt->time_received;
+ }
/* Update the list of ranges to acknowledge. */
if (!quic_update_ack_ranges_list(&qel->pktns->rx.arngs, &ar))
TRACE_DEVEL("Could not update ack range list",
@@ -3671,9 +3674,14 @@
}
HA_RWLOCK_WRUNLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
- /* Update the largest packet number. */
- if (largest_pn != -1 && largest_pn > qel->pktns->rx.largest_pn)
+ if (largest_pn != -1 && largest_pn > qel->pktns->rx.largest_pn) {
+ /* Update the largest packet number. */
qel->pktns->rx.largest_pn = largest_pn;
+ /* Update the largest acknowledged packet timestamps */
+ qel->pktns->rx.largest_time_received = largest_pn_time_received;
+ qel->pktns->flags |= QUIC_FL_PKTNS_NEW_LARGEST_PN;
+ }
+
if (!qc_treat_rx_crypto_frms(qel, ctx))
goto err;
@@ -5787,9 +5795,15 @@
/* Build an ACK frame if required. */
ack_frm_len = 0;
if ((qel->pktns->flags & QUIC_FL_PKTNS_ACK_REQUIRED) && !qel->pktns->tx.pto_probe) {
+ struct quic_arngs *arngs = &qel->pktns->rx.arngs;
BUG_ON(eb_is_empty(&qel->pktns->rx.arngs.root));
- ack_frm.tx_ack.ack_delay = 0;
- ack_frm.tx_ack.arngs = &qel->pktns->rx.arngs;
+ ack_frm.tx_ack.arngs = arngs;
+ if (qel->pktns->flags & QUIC_FL_PKTNS_NEW_LARGEST_PN) {
+ qel->pktns->tx.ack_delay =
+ quic_compute_ack_delay_us(qel->pktns->rx.largest_time_received, qc);
+ qel->pktns->flags &= ~QUIC_FL_PKTNS_NEW_LARGEST_PN;
+ }
+ ack_frm.tx_ack.ack_delay = qel->pktns->tx.ack_delay;
/* XXX BE CAREFUL XXX : here we reserved at least one byte for the
* smallest frame (PING) and <*pn_len> more for the packet number. Note
* that from here, we do not know if we will have to send a PING frame.
@@ -6201,6 +6215,7 @@
if (!pkt)
goto err;
+ pkt->time_received = now_ms;
quic_rx_packet_refinc(pkt);
qc_lstnr_pkt_rcv(pos, end, pkt, first_pkt, dgram);
first_pkt = 0;