PERFORCE change 171474 for review

[Alexander Motin]

http://p4web.freebsd.org/chv.cgi?CH=171474

Change 171474 by mav at mav_mavtest on 2009/12/06 23:25:51

	Be more polite to freeze underruns in production.
	It is bad, but not fatal.

Affected files ...

.. //depot/projects/scottl-camlock/src/sys/cam/cam_xpt.c#133 edit

Differences ...

==== //depot/projects/scottl-camlock/src/sys/cam/cam_xpt.c#133 (text+ko) ====

@@ -4152,7 +4152,10 @@
 	KASSERT(count <= dev->ccbq.queue.qfrozen_cnt,
 	    ("xpt_release_devq: requested %u > present %u\n",
 	    count, dev->ccbq.queue.qfrozen_cnt));
-	dev->ccbq.queue.qfrozen_cnt -= count;
+	if (count <= dev->ccbq.queue.qfrozen_cnt)
+		dev->ccbq.queue.qfrozen_cnt -= count;
+	else
+		dev->ccbq.queue.qfrozen_cnt = 0;
 	if (dev->ccbq.queue.qfrozen_cnt == 0) {
 		/*
 		 * No longer need to wait for a successful
@@ -4190,7 +4193,8 @@
 	KASSERT(sendq->qfrozen_cnt > 0,
 	    ("xpt_release_simq: requested 1 > present %u\n",
 	    sendq->qfrozen_cnt));
-	sendq->qfrozen_cnt--;
+	if (sendq->qfrozen_cnt > 0)
+		sendq->qfrozen_cnt--;
 	if (sendq->qfrozen_cnt == 0) {
 		/*
 		 * If there is a timeout scheduled to release this