From 849eac52f2e0be6b77cf5756053a9984996edf81 Mon Sep 17 00:00:00 2001
From: mjacob <mjacob@NetBSD.org>
Date: Tue, 18 Sep 2001 20:20:26 +0000
Subject: [PATCH] Rather than run a periph's queue from
 scsipi_periph_timed_thaw which is called via a callout, kick the completion
 thread to run it for us (uses a new flag, SCSIPI_CHAN_KICK).

If we've received BUSY status and we haven't started the completion
thread yet, don't freeze do a callout to scsipi_periph_timed_thaw which
then will try and kick the completion thread- instead treat the command
as if it were a polled command and just call delay for 1 second.

If DIAGNOSTIC is defined, and the periph qfreeze count is less than
zero, panic because some HBA has corrupted the periph structure's
accounting.
---
 sys/dev/scsipi/scsipi_base.c | 42 +++++++++++++++++++++++++++---------
 sys/dev/scsipi/scsipiconf.h  |  4 +++-
 2 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/sys/dev/scsipi/scsipi_base.c b/sys/dev/scsipi/scsipi_base.c
index 43b19baae754..44375e80ab10 100644
--- a/sys/dev/scsipi/scsipi_base.c
+++ b/sys/dev/scsipi/scsipi_base.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: scsipi_base.c,v 1.55 2001/09/01 00:54:38 mjacob Exp $	*/
+/*	$NetBSD: scsipi_base.c,v 1.56 2001/09/18 20:20:26 mjacob Exp $	*/
 
 /*-
  * Copyright (c) 1998, 1999, 2000 The NetBSD Foundation, Inc.
@@ -621,6 +621,14 @@ scsipi_periph_thaw(periph, count)
 
 	s = splbio();
 	periph->periph_qfreeze -= count;
+#ifdef DIAGNOSTIC
+	if (periph->periph_qfreeze < 0) {
+		static const char pc[] = "periph freeze count < 0";
+		scsipi_printaddr(periph);
+		printf("%s\n", pc);
+		panic(pc);
+	}
+#endif
 	if (periph->periph_qfreeze == 0 &&
 	    (periph->periph_flags & PERIPH_WAITING) != 0)
 		wakeup(periph);
@@ -636,17 +644,20 @@ void
 scsipi_periph_timed_thaw(arg)
 	void *arg;
 {
+	int s;
 	struct scsipi_periph *periph = arg;
 
 	callout_stop(&periph->periph_callout);
+
+	s = splbio();
 	scsipi_periph_thaw(periph, 1);
 
 	/*
-	 * Kick the channel's queue here.  Note, we're running in
-	 * interrupt context (softclock), so the adapter driver
-	 * had better not sleep.
+	 * Tell the completion thread to kick the channel's queue here.
 	 */
-	scsipi_run_queue(periph->periph_channel);
+	periph->periph_channel->chan_flags |= SCSIPI_CHAN_KICK;
+	wakeup(&periph->periph_channel->chan_complete);
+	splx(s);
 }
 
 /*
@@ -919,7 +930,6 @@ scsipi_interpret_sense(xs)
 		printf("\n");
 	}
 #else
-
 		scsipi_printaddr(periph);
 		printf("Sense Error Code 0x%x",
 			sense->error_code & SSD_ERRCODE);
@@ -1413,9 +1423,10 @@ scsipi_complete(xs)
 			/*
 			 * Wait one second, and try again.
 			 */
-			if (xs->xs_control & XS_CTL_POLL)
+			if ((xs->xs_control & XS_CTL_POLL) ||
+			    (chan->chan_flags & SCSIPI_CHAN_TACTIVE) == 0) {
 				delay(1000000);
-			else {
+			} else {
 				scsipi_periph_freeze(periph, 1);
 				callout_reset(&periph->periph_callout,
 				    hz, scsipi_periph_timed_thaw, periph);
@@ -1505,7 +1516,7 @@ scsipi_complete(xs)
 		} else {
 			bp->b_error = 0;
 			bp->b_resid = xs->resid;
-		}
+																		}
 		biodone(bp);
 	}
 
@@ -1942,12 +1953,16 @@ scsipi_completion_thread(arg)
 	struct scsipi_xfer *xs;
 	int s;
 
+	s = splbio();
+	chan->chan_flags |= SCSIPI_CHAN_TACTIVE;
+	splx(s);
 	for (;;) {
 		s = splbio();
 		xs = TAILQ_FIRST(&chan->chan_complete);
 		if (xs == NULL &&
 		    (chan->chan_flags &
-		     (SCSIPI_CHAN_SHUTDOWN | SCSIPI_CHAN_CALLBACK)) == 0) {
+		     (SCSIPI_CHAN_SHUTDOWN | SCSIPI_CHAN_CALLBACK |
+		     SCSIPI_CHAN_KICK)) == 0) {
 			(void) tsleep(&chan->chan_complete, PRIBIO,
 			    "sccomp", 0);
 			splx(s);
@@ -1960,6 +1975,13 @@ scsipi_completion_thread(arg)
 			splx(s);
 			continue;
 		}
+		if (chan->chan_flags & SCSIPI_CHAN_KICK) {
+			/* explicitly run the queues for this channel */
+			chan->chan_flags &= ~SCSIPI_CHAN_KICK;
+			scsipi_run_queue(chan);
+			splx(s);
+			continue;
+		}
 		if (chan->chan_flags & SCSIPI_CHAN_SHUTDOWN) {
 			splx(s);
 			break;
diff --git a/sys/dev/scsipi/scsipiconf.h b/sys/dev/scsipi/scsipiconf.h
index 1f04f0e7f195..428300b95086 100644
--- a/sys/dev/scsipi/scsipiconf.h
+++ b/sys/dev/scsipi/scsipiconf.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: scsipiconf.h,v 1.57 2001/09/02 13:11:53 tsutsui Exp $	*/
+/*	$NetBSD: scsipiconf.h,v 1.58 2001/09/18 20:20:26 mjacob Exp $	*/
 
 /*-
  * Copyright (c) 1998, 1999, 2000 The NetBSD Foundation, Inc.
@@ -305,6 +305,8 @@ struct scsipi_channel {
 #define	SCSIPI_CHAN_CANGROW	0x04	/* channel can grow resources */
 #define	SCSIPI_CHAN_NOSETTLE	0x08	/* don't wait for devices to settle */
 #define	SCSIPI_CHAN_CALLBACK	0x10	/* has to call chan_callback() */
+#define	SCSIPI_CHAN_KICK	0x20	/* need to run queues */
+#define	SCSIPI_CHAN_TACTIVE	0x40	/* completion thread is active */
 
 #define	SCSIPI_CHAN_MAX_PERIPH(chan)					\
 	(((chan)->chan_flags & SCSIPI_CHAN_OPENINGS) ?			\