Clean up unused bandwidth entry in the TCP hostcache.

Submitted by:		Jason Wolfe (j at nitrology dot com)
Reviewed by:		rrs, hiren
Sponsored by:		Limelight Networks
Differential Revision:	https://reviews.freebsd.org/D4154

3 files changed, 5 insertions, 17 deletions

diff --git a/sys/netinet/tcp_hostcache.c b/sys/netinet/tcp_hostcache.c
index a492540..5e8342f 100644
--- a/sys/netinet/tcp_hostcache.c
+++ b/sys/netinet/tcp_hostcache.c
@@ -32,8 +32,8 @@
  * table to a dedicated structure indexed by the remote IP address.  It keeps
  * information on the measured TCP parameters of past TCP sessions to allow
  * better initial start values to be used with later connections to/from the
- * same source.  Depending on the network parameters (delay, bandwidth, max
- * MTU, congestion window) between local and remote sites, this can lead to
+ * same source.  Depending on the network parameters (delay, max MTU,
+ * congestion window) between local and remote sites, this can lead to
  * significant speed-ups for new TCP connections after the first one.
  *
  * Due to the tcp_hostcache, all TCP-specific metrics information in the
@@ -440,7 +440,6 @@ tcp_hc_get(struct in_conninfo *inc, struct hc_metrics_lite *hc_metrics_lite)
 	hc_metrics_lite->rmx_ssthresh = hc_entry->rmx_ssthresh;
 	hc_metrics_lite->rmx_rtt = hc_entry->rmx_rtt;
 	hc_metrics_lite->rmx_rttvar = hc_entry->rmx_rttvar;
-	hc_metrics_lite->rmx_bandwidth = hc_entry->rmx_bandwidth;
 	hc_metrics_lite->rmx_cwnd = hc_entry->rmx_cwnd;
 	hc_metrics_lite->rmx_sendpipe = hc_entry->rmx_sendpipe;
 	hc_metrics_lite->rmx_recvpipe = hc_entry->rmx_recvpipe;
@@ -555,14 +554,6 @@ tcp_hc_update(struct in_conninfo *inc, struct hc_metrics_lite *hcml)
 			    (hc_entry->rmx_ssthresh + hcml->rmx_ssthresh) / 2;
 		TCPSTAT_INC(tcps_cachedssthresh);
 	}
-	if (hcml->rmx_bandwidth != 0) {
-		if (hc_entry->rmx_bandwidth == 0)
-			hc_entry->rmx_bandwidth = hcml->rmx_bandwidth;
-		else
-			hc_entry->rmx_bandwidth =
-			    (hc_entry->rmx_bandwidth + hcml->rmx_bandwidth) / 2;
-		/* TCPSTAT_INC(tcps_cachedbandwidth); */
-	}
 	if (hcml->rmx_cwnd != 0) {
 		if (hc_entry->rmx_cwnd == 0)
 			hc_entry->rmx_cwnd = hcml->rmx_cwnd;
@@ -612,7 +603,7 @@ sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS)
 		SBUF_INCLUDENUL);
 
 	sbuf_printf(&sb,
-	        "\nIP address        MTU  SSTRESH      RTT   RTTVAR BANDWIDTH "
+	        "\nIP address        MTU  SSTRESH      RTT   RTTVAR "
 		"    CWND SENDPIPE RECVPIPE HITS  UPD  EXP\n");
 
 #define msec(u) (((u) + 500) / 1000)
@@ -621,8 +612,8 @@ sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS)
 		TAILQ_FOREACH(hc_entry, &V_tcp_hostcache.hashbase[i].hch_bucket,
 			      rmx_q) {
 			sbuf_printf(&sb,
-			    "%-15s %5lu %8lu %6lums %6lums %9lu %8lu %8lu %8lu "
-			    "%4lu %4lu %4i\n",
+			    "%-15s %5lu %8lu %6lums %6lums %8lu %8lu %8lu %4lu "
+			    "%4lu %4i\n",
 			    hc_entry->ip4.s_addr ? inet_ntoa(hc_entry->ip4) :
 #ifdef INET6
 				ip6_sprintf(ip6buf, &hc_entry->ip6),
@@ -635,7 +626,6 @@ sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS)
 				(RTM_RTTUNIT / (hz * TCP_RTT_SCALE))),
 			    msec(hc_entry->rmx_rttvar *
 				(RTM_RTTUNIT / (hz * TCP_RTTVAR_SCALE))),
-			    hc_entry->rmx_bandwidth * 8,
 			    hc_entry->rmx_cwnd,
 			    hc_entry->rmx_sendpipe,
 			    hc_entry->rmx_recvpipe,
diff --git a/sys/netinet/tcp_hostcache.h b/sys/netinet/tcp_hostcache.h
index 05aea12..44875ff 100644
--- a/sys/netinet/tcp_hostcache.h
+++ b/sys/netinet/tcp_hostcache.h
@@ -57,7 +57,6 @@ struct hc_metrics {
 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
 	u_long	rmx_rtt;	/* estimated round trip time */
 	u_long	rmx_rttvar;	/* estimated rtt variance */
-	u_long	rmx_bandwidth;	/* estimated bandwidth */
 	u_long	rmx_cwnd;	/* congestion window */
 	u_long	rmx_sendpipe;	/* outbound delay-bandwidth product */
 	u_long	rmx_recvpipe;	/* inbound delay-bandwidth product */
diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h
index a298edf..bf8347a 100644
--- a/sys/netinet/tcp_var.h
+++ b/sys/netinet/tcp_var.h
@@ -335,7 +335,6 @@ struct hc_metrics_lite {	/* must stay in sync with hc_metrics */
 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
 	u_long	rmx_rtt;	/* estimated round trip time */
 	u_long	rmx_rttvar;	/* estimated rtt variance */
-	u_long	rmx_bandwidth;	/* estimated bandwidth */
 	u_long	rmx_cwnd;	/* congestion window */
 	u_long	rmx_sendpipe;   /* outbound delay-bandwidth product */
 	u_long	rmx_recvpipe;   /* inbound delay-bandwidth product */