Partial MFC r316676 and the required r313045

MFC r316676:

Use estimated RTT for receive buffer auto resizing instead of timestamps.
This is a partial MFC as stable/10 doesn't include the TCP stack
modularisation.

MFC r313045:

Add an mbuf to ipinfo_t translator to finish cleanup of mbuf passing to TCP
probes. This is a partial MFC (missing debug__output & debug__drop changes)
due to the massive amount of additional dtrace changes that would be
required for a full MFC.

Relnotes:	Yes
Sponsored by:	Multiplay

1 files changed, 63 insertions, 58 deletions

diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c
index 254454f..95c4d53 100644
--- a/sys/netinet/tcp_input.c
+++ b/sys/netinet/tcp_input.c
@@ -1469,6 +1469,68 @@ drop:
 		m_freem(m);
 }
 
+/*
+ * Automatic sizing of receive socket buffer.  Often the send
+ * buffer size is not optimally adjusted to the actual network
+ * conditions at hand (delay bandwidth product).  Setting the
+ * buffer size too small limits throughput on links with high
+ * bandwidth and high delay (eg. trans-continental/oceanic links).
+ *
+ * On the receive side the socket buffer memory is only rarely
+ * used to any significant extent.  This allows us to be much
+ * more aggressive in scaling the receive socket buffer.  For
+ * the case that the buffer space is actually used to a large
+ * extent and we run out of kernel memory we can simply drop
+ * the new segments; TCP on the sender will just retransmit it
+ * later.  Setting the buffer size too big may only consume too
+ * much kernel memory if the application doesn't read() from
+ * the socket or packet loss or reordering makes use of the
+ * reassembly queue.
+ *
+ * The criteria to step up the receive buffer one notch are:
+ *  1. Application has not set receive buffer size with
+ *     SO_RCVBUF. Setting SO_RCVBUF clears SB_AUTOSIZE.
+ *  2. the number of bytes received during the time it takes
+ *     one timestamp to be reflected back to us (the RTT);
+ *  3. received bytes per RTT is within seven eighth of the
+ *     current socket buffer size;
+ *  4. receive buffer size has not hit maximal automatic size;
+ *
+ * This algorithm does one step per RTT at most and only if
+ * we receive a bulk stream w/o packet losses or reorderings.
+ * Shrinking the buffer during idle times is not necessary as
+ * it doesn't consume any memory when idle.
+ *
+ * TODO: Only step up if the application is actually serving
+ * the buffer to better manage the socket buffer resources.
+ */
+int
+tcp_autorcvbuf(struct mbuf *m, struct tcphdr *th, struct socket *so,
+    struct tcpcb *tp, int tlen)
+{
+	int newsize = 0;
+
+	if (V_tcp_do_autorcvbuf && (so->so_rcv.sb_flags & SB_AUTOSIZE) &&
+	    tp->t_srtt != 0 && tp->rfbuf_ts != 0 &&
+	    TCP_TS_TO_TICKS(tcp_ts_getticks() - tp->rfbuf_ts) >
+	    (tp->t_srtt >> TCP_RTT_SHIFT)) {
+		if (tp->rfbuf_cnt > (so->so_rcv.sb_hiwat / 8 * 7) &&
+		    so->so_rcv.sb_hiwat < V_tcp_autorcvbuf_max) {
+			newsize = min(so->so_rcv.sb_hiwat +
+			    V_tcp_autorcvbuf_inc, V_tcp_autorcvbuf_max);
+		}
+		TCP_PROBE6(receive__autoresize, NULL, tp, m, tp, th, newsize);
+
+		/* Start over with next RTT. */
+		tp->rfbuf_ts = 0;
+		tp->rfbuf_cnt = 0;
+	} else {
+		tp->rfbuf_cnt += tlen;	/* add up */
+	}
+
+	return (newsize);
+}
+
 static void
 tcp_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so,
     struct tcpcb *tp, int drop_hdrlen, int tlen, uint8_t iptos,
@@ -1811,60 +1873,7 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so,
 				tcp_trace(TA_INPUT, ostate, tp,
 				    (void *)tcp_saveipgen, &tcp_savetcp, 0);
 #endif
-		/*
-		 * Automatic sizing of receive socket buffer.  Often the send
-		 * buffer size is not optimally adjusted to the actual network
-		 * conditions at hand (delay bandwidth product).  Setting the
-		 * buffer size too small limits throughput on links with high
-		 * bandwidth and high delay (eg. trans-continental/oceanic links).
-		 *
-		 * On the receive side the socket buffer memory is only rarely
-		 * used to any significant extent.  This allows us to be much
-		 * more aggressive in scaling the receive socket buffer.  For
-		 * the case that the buffer space is actually used to a large
-		 * extent and we run out of kernel memory we can simply drop
-		 * the new segments; TCP on the sender will just retransmit it
-		 * later.  Setting the buffer size too big may only consume too
-		 * much kernel memory if the application doesn't read() from
-		 * the socket or packet loss or reordering makes use of the
-		 * reassembly queue.
-		 *
-		 * The criteria to step up the receive buffer one notch are:
-		 *  1. the number of bytes received during the time it takes
-		 *     one timestamp to be reflected back to us (the RTT);
-		 *  2. received bytes per RTT is within seven eighth of the
-		 *     current socket buffer size;
-		 *  3. receive buffer size has not hit maximal automatic size;
-		 *
-		 * This algorithm does one step per RTT at most and only if
-		 * we receive a bulk stream w/o packet losses or reorderings.
-		 * Shrinking the buffer during idle times is not necessary as
-		 * it doesn't consume any memory when idle.
-		 *
-		 * TODO: Only step up if the application is actually serving
-		 * the buffer to better manage the socket buffer resources.
-		 */
-			if (V_tcp_do_autorcvbuf &&
-			    (to.to_flags & TOF_TS) &&
-			    to.to_tsecr &&
-			    (so->so_rcv.sb_flags & SB_AUTOSIZE)) {
-				if (TSTMP_GT(to.to_tsecr, tp->rfbuf_ts) &&
-				    to.to_tsecr - tp->rfbuf_ts < hz) {
-					if (tp->rfbuf_cnt >
-					    (so->so_rcv.sb_hiwat / 8 * 7) &&
-					    so->so_rcv.sb_hiwat <
-					    V_tcp_autorcvbuf_max) {
-						newsize =
-						    min(so->so_rcv.sb_hiwat +
-						    V_tcp_autorcvbuf_inc,
-						    V_tcp_autorcvbuf_max);
-					}
-					/* Start over with next RTT. */
-					tp->rfbuf_ts = 0;
-					tp->rfbuf_cnt = 0;
-				} else
-					tp->rfbuf_cnt += tlen;	/* add up */
-			}
+			newsize = tcp_autorcvbuf(m, th, so, tp, tlen);
 
 			/* Add data to socket buffer. */
 			SOCKBUF_LOCK(&so->so_rcv);
@@ -1905,10 +1914,6 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so,
 		win = 0;
 	tp->rcv_wnd = imax(win, (int)(tp->rcv_adv - tp->rcv_nxt));
 
-	/* Reset receive buffer auto scaling when not in bulk receive mode. */
-	tp->rfbuf_ts = 0;
-	tp->rfbuf_cnt = 0;
-
 	switch (tp->t_state) {
 
 	/*