tcp: add AccECN CE packet counters to tcpinfo

Provide diagnostics information around AccECN into the tcpinfo struct. Event: IETF 115 Hackathon Reviewed By: tuexen, #transport Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D37280
freebsd · Nov 6, 2022 · 22c81cc · 22c81cc
1 parent d56c7ac
commit 22c81cc
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Showing 3 changed files with 18 additions and 2 deletions.
diff --git a/sys/netinet/tcp.h b/sys/netinet/tcp.h
@@ -390,7 +390,8 @@ struct tcp_info {
 	u_int32_t	tcpi_snd_zerowin;	/* Zero-sized windows sent */
 
 	/* Accurate ECN counters. */
-	u_int32_t	__tcpi_received_ce;		/* # of CE marks received */
+	u_int32_t	tcpi_delivered_ce;
+	u_int32_t	tcpi_received_ce;		/* # of CE marks received */
 	u_int32_t	__tcpi_delivered_e1_bytes;
 	u_int32_t	__tcpi_delivered_e0_bytes;
 	u_int32_t	__tcpi_delivered_ce_bytes;

diff --git a/sys/netinet/tcp_ecn.c b/sys/netinet/tcp_ecn.c
@@ -325,8 +325,10 @@ tcp_ecn_input_segment(struct tcpcb *tp, uint16_t thflags, int iptos)
 			}
 		} else {
 			/* RFC3168 ECN handling */
-			if ((thflags & (TH_SYN | TH_ECE)) == TH_ECE)
+			if ((thflags & (TH_SYN | TH_ECE)) == TH_ECE) {
 				delta_ace = 1;
+				tp->t_scep++;
+			}
 			if (thflags & TH_CWR) {
 				tp->t_flags2 &= ~TF2_ECN_SND_ECE;
 				tp->t_flags |= TF_ACKNOW;

diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
@@ -1640,6 +1640,19 @@ tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
 		tcp_offload_tcp_info(tp, ti);
 	}
 #endif
+	/*
+	 * AccECN related counters.
+	 */
+	if ((tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT)) ==
+	    (TF2_ECN_PERMIT | TF2_ACE_PERMIT))
+		/*
+		 * Internal counter starts at 5 for AccECN
+		 * but 0 for RFC3168 ECN.
+		 */
+		ti->tcpi_delivered_ce = tp->t_scep - 5;
+	else
+		ti->tcpi_delivered_ce = tp->t_scep;
+	ti->tcpi_received_ce = tp->t_rcep;
 }
 
 /*