Eliminate the use of TS_TIMEOUT and ttstrt(). These are for handling

tab delays etc.  pcvt was using them to recover from a (rarely lost)
race.  Use a little more locking to avoid the race.

1 files changed, 13 insertions, 15 deletions

diff --git a/sys/i386/isa/pcvt/pcvt_drv.c b/sys/i386/isa/pcvt/pcvt_drv.c
index d9b69dc..cdf3073 100644
--- a/sys/i386/isa/pcvt/pcvt_drv.c
+++ b/sys/i386/isa/pcvt/pcvt_drv.c
@@ -928,10 +928,6 @@ pcrint(void)
 
 #if PCVT_NETBSD || PCVT_FREEBSD >= 200
 
-#if PCVT_NETBSD == 9
-extern void ttrstrt();
-#endif /* PCVT_NETBSD == 9 */
-
 void
 pcstart(register struct tty *tp)
 {
@@ -950,26 +946,28 @@ pcstart(register struct tty *tp)
 
 	async_update(UPDATE_KERN);
 
+	rbp = &tp->t_outq;
+
 	/*
-	 * We need to do this outside spl since it could be fairly
-	 * expensive and we don't want our serial ports to overflow.
+	 * Call q_to_b() at spltty() to ensure that the queue is empty when
+	 * the loop terminates.
 	 */
 
-	rbp = &tp->t_outq;
+	s = spltty();
 
 	while (len = q_to_b(rbp, buf, PCVT_PCBURST))
+	{
+		/*
+		 * We need to do this outside spl since it could be fairly
+		 * expensive and we don't want our serial ports to overflow.
+		 */
+		splx(s);
 		sput(&buf[0], 0, len, minor(tp->t_dev));
-
-	s = spltty();
+		s = spltty();
+	}
 
 	tp->t_state &= ~TS_BUSY;
 
-	if (rbp->c_cc)
-	{
-		tp->t_state |= TS_TIMEOUT;
-		timeout(ttrstrt, tp, 1);
-	}
-
 #ifndef TS_ASLEEP /* FreeBSD some time after 2.0.5 */
 	ttwwakeup(tp);
 #else