From owner-freebsd-hackers  Sun Nov  7 19:36:21 1999
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To: freebsd-hackers@FreeBSD.ORG
Subject: SIMPLELOCK_DEBUG and apause
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From: Assar Westerlund <assar@sics.se>
Date: 08 Nov 1999 04:37:24 +0100
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Why trying to debug some locking code of my own I enabled
SIMPLELOCK_DEBUG, only to find out that I was getting lots of
`simple_unlock: lock not held' in lockmgr -> acquire -> apause.

Looking closer at `apause' it seems rather clear that it can cause
this.  I proposed simple change is below.

Comments?

/assar

--- kern_lock.c.orig	Mon Nov  8 03:55:26 1999
+++ kern_lock.c	Mon Nov  8 04:24:13 1999
@@ -116,9 +119,11 @@
 				simple_lock(&lkp->lk_interlock);
 				if ((lkp->lk_flags & flags) == 0)
 					return 0;
+				simple_unlock(&lkp->lk_interlock);
 				break;
 			}
 		}
+		simple_lock(&lkp->lk_interlock);
 	}
 	return 1;
 }


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