From: Frédéric Lécaille <flecaille@haproxy.com>
Date: Thu, 11 Aug 2022 09:40:01 +0000 (+0200)
Subject: MINOR: quic: Remove useless lock for RX packets
X-Git-Tag: v2.7-dev4~59
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a6920a25d98d8b126fe029620e0165d0d2ad15b2;p=thirdparty%2Fhaproxy.git

MINOR: quic: Remove useless lock for RX packets

This lock was there be able to handle the RX packets for a connetion
from several threads. This is no more needed since a QUIC connection
is always handled by the same thread.

May be backported to 2.6
---

diff --git a/include/haproxy/xprt_quic-t.h b/include/haproxy/xprt_quic-t.h
index 2b219eaa1a..f6fcf95e59 100644
--- a/include/haproxy/xprt_quic-t.h
+++ b/include/haproxy/xprt_quic-t.h
@@ -517,8 +517,6 @@ struct quic_enc_level {
 		/* The packets received by the listener I/O handler
 		   with header protection removed. */
 		struct eb_root pkts;
-		/* <pkts> root must be protected from concurrent accesses */
-		__decl_thread(HA_RWLOCK_T pkts_rwlock);
 		/* Liste of QUIC packets with protected header. */
 		struct mt_list pqpkts;
 		/* Crypto frames */
diff --git a/include/haproxy/xprt_quic.h b/include/haproxy/xprt_quic.h
index a9e29cbcd0..4f85be876d 100644
--- a/include/haproxy/xprt_quic.h
+++ b/include/haproxy/xprt_quic.h
@@ -667,9 +667,7 @@ static inline int qc_el_rx_pkts(struct quic_enc_level *qel)
 {
 	int ret;
 
-	HA_RWLOCK_RDLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 	ret = !eb_is_empty(&qel->rx.pkts);
-	HA_RWLOCK_RDUNLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 
 	return ret;
 }
@@ -728,7 +726,6 @@ static inline void qc_el_rx_pkts_del(struct quic_enc_level *qel)
 {
 	struct eb64_node *node;
 
-	HA_RWLOCK_WRLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 	node = eb64_first(&qel->rx.pkts);
 	while (node) {
 		struct quic_rx_packet *pkt =
@@ -738,14 +735,12 @@ static inline void qc_el_rx_pkts_del(struct quic_enc_level *qel)
 		eb64_delete(&pkt->pn_node);
 		quic_rx_packet_refdec(pkt);
 	}
-	HA_RWLOCK_WRUNLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 }
 
 static inline void qc_list_qel_rx_pkts(struct quic_enc_level *qel)
 {
 	struct eb64_node *node;
 
-	HA_RWLOCK_RDLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 	node = eb64_first(&qel->rx.pkts);
 	while (node) {
 		struct quic_rx_packet *pkt;
@@ -755,7 +750,6 @@ static inline void qc_list_qel_rx_pkts(struct quic_enc_level *qel)
 		        pkt, pkt->type, (ull)pkt->pn_node.key);
 		node = eb64_next(node);
 	}
-	HA_RWLOCK_RDUNLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 }
 
 static inline void qc_list_all_rx_pkts(struct quic_conn *qc)
diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index 436f701710..05ff1e7efc 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -3697,10 +3697,8 @@ static inline void qc_rm_hp_pkts(struct quic_conn *qc, struct quic_enc_level *el
 			pqpkt->aad_len = pqpkt->pn_offset + pqpkt->pnl;
 			/* Store the packet into the tree of packets to decrypt. */
 			pqpkt->pn_node.key = pqpkt->pn;
-			HA_RWLOCK_WRLOCK(QUIC_LOCK, &el->rx.pkts_rwlock);
 			eb64_insert(&el->rx.pkts, &pqpkt->pn_node);
 			quic_rx_packet_refinc(pqpkt);
-			HA_RWLOCK_WRUNLOCK(QUIC_LOCK, &el->rx.pkts_rwlock);
 			TRACE_DEVEL("hp removed", QUIC_EV_CONN_ELRMHP, qc, pqpkt);
 		}
 		MT_LIST_DELETE_SAFE(pkttmp1);
@@ -3769,7 +3767,6 @@ int qc_treat_rx_pkts(struct quic_enc_level *cur_el, struct quic_enc_level *next_
 	if (!qel)
 		goto out;
 
-	HA_RWLOCK_WRLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 	node = eb64_first(&qel->rx.pkts);
 	while (node) {
 		struct quic_rx_packet *pkt;
@@ -3811,7 +3808,6 @@ int qc_treat_rx_pkts(struct quic_enc_level *cur_el, struct quic_enc_level *next_
 		eb64_delete(&pkt->pn_node);
 		quic_rx_packet_refdec(pkt);
 	}
-	HA_RWLOCK_WRUNLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 
 	if (largest_pn != -1 && largest_pn > qel->pktns->rx.largest_pn) {
 		/* Update the largest packet number. */
@@ -4325,7 +4321,6 @@ static int quic_conn_enc_level_init(struct quic_conn *qc,
 	qel->tls_ctx.flags = 0;
 
 	qel->rx.pkts = EB_ROOT;
-	HA_RWLOCK_INIT(&qel->rx.pkts_rwlock);
 	MT_LIST_INIT(&qel->rx.pqpkts);
 	qel->rx.crypto.offset = 0;
 	qel->rx.crypto.frms = EB_ROOT_UNIQUE;
@@ -4931,9 +4926,7 @@ static void qc_pkt_insert(struct quic_conn *qc,
 
 	pkt->pn_node.key = pkt->pn;
 	quic_rx_packet_refinc(pkt);
-	HA_RWLOCK_WRLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 	eb64_insert(&qel->rx.pkts, &pkt->pn_node);
-	HA_RWLOCK_WRUNLOCK(QUIC_LOCK, &qel->rx.pkts_rwlock);
 
 	TRACE_LEAVE(QUIC_EV_CONN_RXPKT, qc);
 }