Set the input and output buffer sizes and the input buffer watermarks

dynamically depending on the line speed(s).  This should give the old
sizes and watermarks until drivers are changed.

Display the input watermarks in pstat and sicontrol.

4 files changed, 90 insertions, 49 deletions

diff --git a/sys/kern/tty.c b/sys/kern/tty.c
index bac398b..64dcf31 100644
--- a/sys/kern/tty.c
+++ b/sys/kern/tty.c
@@ -1,3 +1,5 @@
+static volatile int ttyverbose = 0;
+
 /*-
  * Copyright (c) 1982, 1986, 1990, 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -36,7 +38,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty.c	8.8 (Berkeley) 1/21/94
- * $Id: tty.c,v 1.99 1997/12/06 13:23:52 bde Exp $
+ * $Id: tty.c,v 1.100 1997/12/16 17:40:24 eivind Exp $
  */
 
 /*-
@@ -190,16 +192,8 @@ static u_char const char_type[] = {
 #define	CLR(t, f)	(t) &= ~(f)
 #define	ISSET(t, f)	((t) & (f))
 
-/*
- * Input control starts when we would not be able to fit the maximum
- * contents of the ping-pong buffers and finishes when we would be able
- * to fit that much plus 1/8 more.
- */
-#define	I_HIGH_WATER	(TTYHOG - 2 * 256)	/* XXX */
-#define	I_LOW_WATER	((TTYHOG - 2 * 256) * 7 / 8)	/* XXX */
-
 #undef MAX_INPUT		/* XXX wrong in <sys/syslimits.h> */
-#define	MAX_INPUT	TTYHOG
+#define	MAX_INPUT	TTYHOG	/* XXX limit is usually larger for !ICANON */
 
 /*
  * Initial open of tty, or (re)entry to standard tty line discipline.
@@ -219,16 +213,7 @@ ttyopen(device, tp)
 			SET(tp->t_state, TS_CONNECTED);
 		bzero(&tp->t_winsize, sizeof(tp->t_winsize));
 	}
-
-	/*
-	 * Initialize or restore a cblock allocation policy suitable for
-	 * the standard line discipline.
-	 */
-	clist_alloc_cblocks(&tp->t_canq, TTYHOG, 512);
-	clist_alloc_cblocks(&tp->t_outq, TTMAXHIWAT + OBUFSIZ + 100,
-			    TTMAXHIWAT + OBUFSIZ + 100);
-	clist_alloc_cblocks(&tp->t_rawq, TTYHOG, TTYHOG);
-
+	ttsetwater(tp);
 	splx(s);
 	return (0);
 }
@@ -318,7 +303,7 @@ ttyinput(c, tp)
 	 * The 3 is slop for PARMRK.
 	 */
 	iflag = tp->t_iflag;
-	if (tp->t_rawq.c_cc + tp->t_canq.c_cc > I_HIGH_WATER - 3 &&
+	if (tp->t_rawq.c_cc + tp->t_canq.c_cc > tp->t_ihiwat - 3 &&
 	    (!ISSET(lflag, ICANON) || tp->t_canq.c_cc != 0) &&
 	    (ISSET(tp->t_cflag, CRTS_IFLOW) || ISSET(iflag, IXOFF)) &&
 	    !ISSET(tp->t_state, TS_TBLOCK))
@@ -556,7 +541,7 @@ parmrk:
 	if (tp->t_rawq.c_cc + tp->t_canq.c_cc >= MAX_INPUT) {
 input_overflow:
 		if (ISSET(iflag, IMAXBEL)) {
-			if (tp->t_outq.c_cc < tp->t_hiwat)
+			if (tp->t_outq.c_cc < tp->t_ohiwat)
 				(void)ttyoutput(CTRL('g'), tp);
 		}
 		goto endcase;
@@ -1055,7 +1040,7 @@ ttypoll(tp, events, p)
 			selrecord(p, &tp->t_rsel);
 
 	if (events & (POLLOUT | POLLWRNORM))
-		if ((tp->t_outq.c_cc <= tp->t_lowat &&
+		if ((tp->t_outq.c_cc <= tp->t_olowat &&
 		     ISSET(tp->t_state, TS_CONNECTED))
 		    || ISSET(tp->t_state, TS_ZOMBIE))
 			revents |= events & (POLLOUT | POLLWRNORM);
@@ -1681,7 +1666,7 @@ out:
 	 */
 	s = spltty();
 	if (ISSET(tp->t_state, TS_TBLOCK) &&
-	    tp->t_rawq.c_cc + tp->t_canq.c_cc <= I_LOW_WATER)
+	    tp->t_rawq.c_cc + tp->t_canq.c_cc <= tp->t_ilowat)
 		ttyunblock(tp);
 	splx(s);
 
@@ -1702,7 +1687,7 @@ ttycheckoutq(tp, wait)
 {
 	int hiwat, s, oldsig;
 
-	hiwat = tp->t_hiwat;
+	hiwat = tp->t_ohiwat;
 	s = spltty();
 	oldsig = wait ? curproc->p_siglist : 0;
 	if (tp->t_outq.c_cc > hiwat + OBUFSIZ + 100)
@@ -1736,7 +1721,7 @@ ttwrite(tp, uio, flag)
 	int i, hiwat, cnt, error, s;
 	char obuf[OBUFSIZ];
 
-	hiwat = tp->t_hiwat;
+	hiwat = tp->t_ohiwat;
 	cnt = uio->uio_resid;
 	error = 0;
 	cc = 0;
@@ -2111,7 +2096,7 @@ ttwwakeup(tp)
 	register struct tty *tp;
 {
 
-	if (tp->t_wsel.si_pid != 0 && tp->t_outq.c_cc <= tp->t_lowat)
+	if (tp->t_wsel.si_pid != 0 && tp->t_outq.c_cc <= tp->t_olowat)
 		selwakeup(&tp->t_wsel);
 	if (ISSET(tp->t_state, TS_BUSY | TS_SO_OCOMPLETE) ==
 	    TS_SO_OCOMPLETE && tp->t_outq.c_cc == 0) {
@@ -2119,7 +2104,7 @@ ttwwakeup(tp)
 		wakeup(TSA_OCOMPLETE(tp));
 	}
 	if (ISSET(tp->t_state, TS_SO_OLOWAT) &&
-	    tp->t_outq.c_cc <= tp->t_lowat) {
+	    tp->t_outq.c_cc <= tp->t_olowat) {
 		CLR(tp->t_state, TS_SO_OLOWAT);
 		wakeup(TSA_OLOWAT(tp));
 	}
@@ -2142,25 +2127,72 @@ ttspeedtab(speed, table)
 }
 
 /*
- * Set tty hi and low water marks.
- *
- * Try to arrange the dynamics so there's about one second
- * from hi to low water.
- *
+ * Set input and output watermarks and buffer sizes.  For input, the
+ * high watermark is about one second's worth of input above empty, the
+ * low watermark is slightly below high water, and the buffer size is a
+ * driver-dependent amount above high water.  For output, the watermarks
+ * are near the ends of the buffer, with about 1 second's worth of input
+ * between them.  All this only applies to the standard line discipline.
  */
 void
 ttsetwater(tp)
 	struct tty *tp;
 {
-	register int cps, x;
+	register int cps, ttmaxhiwat, x;
 
+	/* Input. */
+	clist_alloc_cblocks(&tp->t_canq, TTYHOG, 512);
+	if (ttyverbose)
+		printf("ttsetwater: can: %d, ", TTYHOG);
+	switch (tp->t_ispeedwat) {
+	case (speed_t)-1:
+		cps = tp->t_ispeed / 10;
+		break;
+	case 0:
+		/*
+		 * This case is for old drivers that don't know about
+		 * t_ispeedwat.  Arrange for them to get the old buffer
+		 * sizes and watermarks.
+		 */
+		cps = TTYHOG - 2 * 256;
+		tp->t_ififosize = 2 * 256;
+		break;
+	default:
+		cps = tp->t_ispeedwat / 10;
+		break;
+	}
+	tp->t_ihiwat = cps;
+	tp->t_ilowat = 7 * cps / 8;
+	x = cps + tp->t_ififosize;
+	clist_alloc_cblocks(&tp->t_rawq, x, x);
+	if (ttyverbose)
+		printf("raw: %d, ", x);
+
+	/* Output. */
+	switch (tp->t_ospeedwat) {
+	case (speed_t)-1:
+		cps = tp->t_ospeed / 10;
+		ttmaxhiwat = 200000;
+		break;
+	case 0:
+		cps = tp->t_ospeed / 10;
+		ttmaxhiwat = TTMAXHIWAT;
+		break;
+	default:
+		cps = tp->t_ospeedwat / 10;
+		ttmaxhiwat = 200000;
+		break;
+	}
 #define CLAMP(x, h, l)	((x) > h ? h : ((x) < l) ? l : (x))
-
-	cps = tp->t_ospeed / 10;
-	tp->t_lowat = x = CLAMP(cps / 2, TTMAXLOWAT, TTMINLOWAT);
+	tp->t_olowat = x = CLAMP(cps / 2, TTMAXLOWAT, TTMINLOWAT);
 	x += cps;
-	x = CLAMP(x, TTMAXHIWAT, TTMINHIWAT);
-	tp->t_hiwat = roundup(x, CBSIZE);
+	x = CLAMP(x, ttmaxhiwat, TTMINHIWAT);	/* XXX clamps are too magic */
+	tp->t_ohiwat = roundup(x, CBSIZE);	/* XXX for compat */
+	x = imax(tp->t_ohiwat, TTMAXHIWAT);	/* XXX for compat/safety */
+	x += OBUFSIZ + 100;
+	clist_alloc_cblocks(&tp->t_outq, x, x);
+	if (ttyverbose)
+		printf("out: %d\n", x);
 #undef	CLAMP
 }
 
diff --git a/sys/sys/tty.h b/sys/sys/tty.h
index bf0ec88..b7a59e8 100644
--- a/sys/sys/tty.h
+++ b/sys/sys/tty.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty.h	8.6 (Berkeley) 1/21/94
- * $Id: tty.h,v 1.39 1997/09/14 02:25:41 peter Exp $
+ * $Id: tty.h,v 1.40 1997/10/12 20:26:06 phk Exp $
  */
 
 #ifndef _SYS_TTY_H_
@@ -92,8 +92,13 @@ struct tty {
 	void	*t_sc;			/* XXX: net/if_sl.c:sl_softc. */
 	int	t_column;		/* Tty output column. */
 	int	t_rocount, t_rocol;	/* Tty. */
-	int	t_hiwat;		/* High water mark. */
-	int	t_lowat;		/* Low water mark. */
+	int	t_ififosize;		/* Total size of upstream fifos. */
+	int	t_ihiwat;		/* High water mark for input. */
+	int	t_ilowat;		/* Low water mark for input. */
+	speed_t	t_ispeedwat;		/* t_ispeed override for watermarks. */
+	int	t_ohiwat;		/* High water mark for output. */
+	int	t_olowat;		/* Low water mark for output. */
+	speed_t	t_ospeedwat;		/* t_ospeed override for watermarks. */
 	int	t_gen;			/* Generation number. */
 };
 
diff --git a/usr.sbin/pstat/pstat.c b/usr.sbin/pstat/pstat.c
index 7fc3f08..d5a26a6 100644
--- a/usr.sbin/pstat/pstat.c
+++ b/usr.sbin/pstat/pstat.c
@@ -42,7 +42,7 @@ static const char copyright[] =
 static char sccsid[] = "@(#)pstat.c	8.16 (Berkeley) 5/9/95";
 #endif
 static const char rcsid[] =
-	"$Id: pstat.c,v 1.33 1997/11/12 05:42:33 julian Exp $";
+	"$Id: pstat.c,v 1.34 1998/01/06 05:33:28 dyson Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -727,7 +727,8 @@ kinfo_vnodes(avnodes)
 	return ((struct e_vnode *)vbuf);
 }
 
-char hdr[]="  LINE RAW CAN OUT  HWT LWT     COL STATE  SESS      PGID DISC\n";
+char hdr[] =
+"  LINE RAW CAN OUT IHWT LWT OHWT LWT     COL STATE  SESS      PGID DISC\n";
 int ttyspace = 128;
 
 void
@@ -894,8 +895,9 @@ ttyprt(tp, line)
 	else
 		(void)printf("%7s ", name);
 	(void)printf("%2d %3d ", tp->t_rawq.c_cc, tp->t_canq.c_cc);
-	(void)printf("%3d %4d %3d %7d ", tp->t_outq.c_cc,
-		tp->t_hiwat, tp->t_lowat, tp->t_column);
+	(void)printf("%3d %4d %3d %4d %3d %7d ", tp->t_outq.c_cc,
+		tp->t_ihiwat, tp->t_ilowat, tp->t_ohiwat, tp->t_olowat,
+		tp->t_column);
 	for (i = j = 0; ttystates[i].flag; i++)
 		if (tp->t_state&ttystates[i].flag)
 			state[j++] = ttystates[i].val;
diff --git a/usr.sbin/sicontrol/sicontrol.c b/usr.sbin/sicontrol/sicontrol.c
index eb93819..cda0346 100644
--- a/usr.sbin/sicontrol/sicontrol.c
+++ b/usr.sbin/sicontrol/sicontrol.c
@@ -33,7 +33,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-	"$Id$";
+	"$Id: sicontrol.c,v 1.7 1997/10/15 06:43:54 charnier Exp $";
 #endif /* not lint */
 
 #include <ctype.h>
@@ -488,8 +488,10 @@ char **av;
 	printf("\tt_dev 0x%x\n", TTY.t_dev);		/* dev_t t_dev */
 	printf("\tt_flags 0x%x\n", TTY.t_flags);	/* int	t_flags */
 	printf("\tt_state 0x%x\n", TTY.t_state);	/* int	t_state */
-	printf("\tt_hiwat %d.\n", TTY.t_hiwat);		/* short t_hiwat */
-	printf("\tt_lowat %d.\n", TTY.t_lowat);		/* short t_lowat */
+	printf("\tt_ihiwat %d.\n", TTY.t_ihiwat);	/* int	t_ihiwat */
+	printf("\tt_ilowat %d.\n", TTY.t_ilowat);	/* int	t_ilowat */
+	printf("\tt_ohiwat %d.\n", TTY.t_ohiwat);	/* int	t_ohiwat */
+	printf("\tt_olowat %d.\n", TTY.t_olowat);	/* int	t_olowat */
 	printf("\tt_iflag 0x%x\n", TTY.t_iflag);	/* t_iflag */
 	printf("\tt_oflag 0x%x\n", TTY.t_oflag);	/* t_oflag */
 	printf("\tt_cflag 0x%x\n", TTY.t_cflag);	/* t_cflag */