svn commit: r184771 - in head/sys: dev/syscons kern sys

[Ed Schouten]

Author: ed
Date: Sat Nov  8 20:40:39 2008
New Revision: 184771
URL: http://svn.freebsd.org/changeset/base/184771

Log:
  Reduce the default baud rate of PTY's to 9600.
  
  On RELENG_6 (and probably RELENG_7) we see our syscons windows and
  pseudo-terminals have the following buffer sizes:
  
  | LINE RAW CAN OUT IHIWT ILOWT OHWT LWT     COL STATE  SESS      PGID DISC
  | ttyv0  0   0   0  7680  6720 2052 256       7 OCcl       1146  1146 term
  | ttyp0  0   0   0  7680  6720 1296 256       0 OCc       82033 82033 term
  
  These buffer sizes make no sense, because we often have much more output
  than input, but I guess having higher input buffer sizes improves
  guarantees of the system.
  
  On MPSAFE TTY I just sent both the input and output buffer sizes to 7
  KB, which is pretty big on a standard FreeBSD install with 8 syscons
  windows and some PTY's. Reduce the baud rate to 9600 baud, which means
  we now have the following buffer sizes:
  
  |  LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   COL  SESS  PGID STATE
  | ttyv0  1920    0    0  192  1984    0  199     7  2401  2401 Oil
  | pts/0  1920    0    0  192  1984    0  199  5631  1305  2526 Oi
  
  This is a lot smaller, but for pseudo-devices this should be good
  enough. You need to do a lot of punching to fill up a 7.5 KB input
  buffer. If it turns out things don't work out this way, we'll just
  switch to 19200 baud.

Modified:
  head/sys/dev/syscons/sysmouse.c
  head/sys/kern/tty.c
  head/sys/sys/ttydefaults.h

Modified: head/sys/dev/syscons/sysmouse.c
==============================================================================
--- head/sys/dev/syscons/sysmouse.c	Sat Nov  8 19:56:32 2008	(r184770)
+++ head/sys/dev/syscons/sysmouse.c	Sat Nov  8 20:40:39 2008	(r184771)
@@ -148,7 +148,7 @@ smdev_param(struct tty *tp, struct termi
 	 * Set the output baud rate to zero. The mouse device supports
 	 * no output, so we don't want to waste buffers.
 	 */
-	t->c_ispeed = TTYDEF_SPEED_PSEUDO;
+	t->c_ispeed = TTYDEF_SPEED;
 	t->c_ospeed = B0;
 
 	return (0);

Modified: head/sys/kern/tty.c
==============================================================================
--- head/sys/kern/tty.c	Sat Nov  8 19:56:32 2008	(r184770)
+++ head/sys/kern/tty.c	Sat Nov  8 20:40:39 2008	(r184771)
@@ -802,7 +802,7 @@ ttydevsw_defparam(struct tty *tp, struct
 {
 
 	/* Use a fake baud rate, we're not a real device. */
-	t->c_ispeed = t->c_ospeed = TTYDEF_SPEED_PSEUDO;
+	t->c_ispeed = t->c_ospeed = TTYDEF_SPEED;
 
 	return (0);
 }

Modified: head/sys/sys/ttydefaults.h
==============================================================================
--- head/sys/sys/ttydefaults.h	Sat Nov  8 19:56:32 2008	(r184770)
+++ head/sys/sys/ttydefaults.h	Sat Nov  8 20:40:39 2008	(r184771)
@@ -52,7 +52,6 @@
 #define	TTYDEF_LFLAG TTYDEF_LFLAG_ECHO
 #define	TTYDEF_CFLAG	(CREAD | CS8 | HUPCL)
 #define	TTYDEF_SPEED	(B9600)
-#define	TTYDEF_SPEED_PSEUDO (B38400)
 
 /*
  * Control Character Defaults