MINOR: quic: remove unused pacing burst in bind_conf/quic_cc_path

Pacing burst size is now dynamic. As such, configuration value has been
removed and related fields in bind_conf and quic_cc_path structures can
be safely removed.

This should be backported up to 3.1.

include/haproxy/listener-t.h

@@ -185,7 +185,6 @@ struct bind_conf {
 	struct quic_cc_algo *quic_cc_algo; /* QUIC control congestion algorithm */
 	size_t max_cwnd;                   /* QUIC maximumu congestion control window size (kB) */
 	enum quic_sock_mode quic_mode;     /* QUIC socket allocation strategy */
-	int quic_pacing_burst;             /* QUIC allowed pacing burst size */
 #endif
 	struct proxy *frontend;    /* the frontend all these listeners belong to, or NULL */
 	const struct mux_proto_list *mux_proto; /* the mux to use for all incoming connections (specified by the "proto" keyword) */

include/haproxy/quic_cc-t.h

@@ -118,8 +118,6 @@ struct quic_cc_path {
 	uint64_t in_flight;
 	/* Number of in flight ack-eliciting packets. */
 	uint64_t ifae_pkts;
-	/* Burst size if pacing is used. Not used if congestion algo handle pacing itself. */
-	uint32_t pacing_burst;
 	uint64_t delivery_rate; /* bytes per second */
 	size_t send_quantum;
 	uint32_t recovery_start_ts;

include/haproxy/quic_cc.h

@@ -39,7 +39,6 @@ void quic_cc_state_trace(struct buffer *buf, const struct quic_cc *cc);
 
 /* Pacing callbacks */
 uint quic_cc_default_pacing_inter(const struct quic_cc *cc);
-uint quic_cc_default_pacing_burst(const struct quic_cc *cc);
 
 static inline const char *quic_cc_state_str(enum quic_cc_algo_state_type state)
 {
@@ -82,7 +81,7 @@ static inline void *quic_cc_priv(const struct quic_cc *cc)
  * which is true for an IPv4 path, if not false for an IPv6 path.
  */
 static inline void quic_cc_path_init(struct quic_cc_path *path, int ipv4, unsigned long max_cwnd,
-                                     struct quic_cc_algo *algo, int burst,
+                                     struct quic_cc_algo *algo,
                                      struct quic_conn *qc)
 {
 	unsigned int max_dgram_sz;
@@ -98,7 +97,6 @@ static inline void quic_cc_path_init(struct quic_cc_path *path, int ipv4, unsign
 	path->prep_in_flight = 0;
 	path->in_flight = 0;
 	path->ifae_pkts = 0;
-	path->pacing_burst = burst;
 	quic_cc_init(&path->cc, algo, qc);
 	path->delivery_rate = 0;
 	path->send_quantum = 64 * 1024;

src/cfgparse-quic.c

@@ -202,9 +202,7 @@ static int bind_parse_quic_cc_algo(char **args, int cur_arg, struct proxy *px,
 					goto fail;
 				}
 
-				conf->quic_pacing_burst = burst;
 				cc_algo->pacing_inter = quic_cc_default_pacing_inter;
-				cc_algo->pacing_burst = quic_cc_default_pacing_burst;
 			}
 
 			if (*end_opt == ')') {

src/listener.c

@@ -2040,7 +2040,6 @@ struct bind_conf *bind_conf_alloc(struct proxy *fe, const char *file,
 	/* Use connection socket for QUIC by default. */
 	bind_conf->quic_mode = QUIC_SOCK_MODE_CONN;
 	bind_conf->max_cwnd = global.tune.quic_frontend_max_window_size;
-	bind_conf->quic_pacing_burst = 0;
 #endif
 	LIST_INIT(&bind_conf->listeners);
 

src/quic_cc.c

@@ -57,15 +57,6 @@ uint quic_cc_default_pacing_inter(const struct quic_cc *cc)
 	return path->loss.srtt * 1000000 / (path->cwnd / path->mtu + 1) + 1;
 }
 
-/* Return the max number of datagrams which can be emitted in a burst with
- * pacing. Must return a strictly positive value.
- */
-uint quic_cc_default_pacing_burst(const struct quic_cc *cc)
-{
-	struct quic_cc_path *path = container_of(cc, struct quic_cc_path, cc);
-	return path->pacing_burst;
-}
-
 /* Returns true if congestion window on path ought to be increased. */
 int quic_cwnd_may_increase(const struct quic_cc_path *path)
 {

src/quic_conn.c

@@ -1225,8 +1225,7 @@ struct quic_conn *qc_new_conn(const struct quic_version *qv, int ipv4,
 	/* Only one path at this time (multipath not supported) */
 	qc->path = &qc->paths[0];
 	quic_cc_path_init(qc->path, ipv4, server ? l->bind_conf->max_cwnd : 0,
-	                  cc_algo ? cc_algo : default_quic_cc_algo,
-	                  l->bind_conf->quic_pacing_burst, qc);
+	                  cc_algo ? cc_algo : default_quic_cc_algo, qc);
 
 	memcpy(&qc->local_addr, local_addr, sizeof(qc->local_addr));
 	memcpy(&qc->peer_addr, peer_addr, sizeof qc->peer_addr);