From 19b0efd32d5085fb6a2fdb4618c7a4217c53b4bb Mon Sep 17 00:00:00 2001
From: Pawel Jakub Dawidek <pjd@FreeBSD.org>
Date: Wed, 4 Feb 2004 08:14:58 +0000
Subject: [PATCH] Allow assert that the current thread does not hold the sx(9)
 lock.

Reviewed by:		jhb
In cooperation with:	juli, jhb
Approved by:		jhb, scottl (mentor)
---
 sys/kern/kern_sx.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/sys/kern/kern_sx.c b/sys/kern/kern_sx.c
index fd723ed513c..e744f315b8f 100644
--- a/sys/kern/kern_sx.c
+++ b/sys/kern/kern_sx.c
@@ -344,6 +344,17 @@ _sx_assert(struct sx *sx, int what, const char *file, int line)
 			    sx->sx_object.lo_name, file, line);
 		mtx_unlock(sx->sx_lock);
 		break;
+	case SX_UNLOCKED:
+#ifdef WITNESS
+		witness_assert(&sx->sx_object, what, file, line);
+#else
+		mtx_lock(sx->sx_lock);
+		if (sx->sx_cnt != 0 && sx->sx_xholder == curthread)
+			printf("Lock %s locked @ %s:%d\n",
+			    sx->sx_object.lo_name, file, line);
+		mtx_unlock(sx->sx_lock);
+#endif
+		break;
 	default:
 		panic("Unknown sx lock assertion: %d @ %s:%d", what, file,
 		    line);