PERFORCE change 94944 for review

[John Baldwin]

http://perforce.freebsd.org/chv.cgi?CH=94944

Change 94944 by jhb at jhb_slimer on 2006/04/10 19:16:57

	Various upgrade/downgrade tests for rwlocks.

Affected files ...

.. //depot/projects/smpng/sys/modules/crash/crash.c#31 edit

Differences ...

==== //depot/projects/smpng/sys/modules/crash/crash.c#31 (text+ko) ====

@@ -86,6 +86,73 @@
 
 /* Events. */
 
+static void
+upgrade_baz(void)
+{
+	rw_init(&baz, "baz");
+	rw_rlock(&baz);
+	if (rw_try_upgrade(&baz) == 0) {
+		printf("crash: umm, upgrade failed?\n");
+		rw_runlock(&baz);
+	} else
+		rw_wunlock(&baz);
+	rw_destroy(&baz);
+}
+CRASH_EVENT("rlock baz, upgrade, and release", upgrade_baz);
+
+static void
+downgrade_baz(void)
+{
+	rw_init(&baz, "baz");
+	rw_wlock(&baz);
+	rw_downgrade(&baz);
+	rw_runlock(&baz);
+	rw_destroy(&baz);
+}
+CRASH_EVENT("wlock baz, downgrade, and release", downgrade_baz);
+
+static void
+upgrade_excl_baz(void)
+{
+	rw_init(&baz, "baz");
+	rw_wlock(&baz);
+	rw_try_upgrade(&baz);
+	rw_destroy(&baz);
+}
+CRASH_EVENT("wlock baz, upgrade", upgrade_excl_baz);
+
+static void
+downgrade_shared_baz(void)
+{
+	rw_init(&baz, "baz");
+	rw_rlock(&baz);
+	rw_downgrade(&baz);
+	rw_destroy(&baz);
+}
+CRASH_EVENT("rlock baz, downgrade", downgrade_shared_baz);
+
+static void
+runlock_upgraded_baz(void)
+{
+	rw_init(&baz, "baz");
+	rw_rlock(&baz);
+	rw_try_upgrade(&baz);
+	rw_runlock(&baz);
+	rw_destroy(&baz);
+}
+CRASH_EVENT("rlock baz, upgrade, runlock", runlock_upgraded_baz);
+
+static void
+wunlock_downgraded_baz(void)
+{
+	rw_init(&baz, "baz");
+	rw_wlock(&baz);
+	rw_downgrade(&baz);
+	rw_wunlock(&baz);
+	rw_destroy(&baz);
+}
+CRASH_EVENT("wlock baz, downgrade, wunlock", wunlock_downgraded_baz);
+
 #ifdef WITNESS
 
 static void
@@ -356,8 +423,8 @@
 	if (sx_try_upgrade(&foo) == 0) {
 		printf("crash: umm, upgrade failed?\n");
 		sx_sunlock(&foo);
-	}
-	sx_xunlock(&foo);
+	} else
+		sx_xunlock(&foo);
 }
 CRASH_EVENT("slock foo, upgrade, and release", upgrade_foo);