PERFORCE change 103893 for review

[John Baldwin]

http://perforce.freebsd.org/chv.cgi?CH=103893

Change 103893 by jhb at jhb_mutex on 2006/08/14 19:53:56

	Add a mutex cycle.

Affected files ...

.. //depot/projects/smpng/sys/modules/crash2/crash2.c#12 edit

Differences ...

==== //depot/projects/smpng/sys/modules/crash2/crash2.c#12 (text+ko) ====

@@ -88,6 +88,7 @@
 static int event[NTHREADS];
 static struct rwlock foo;
 static struct mtx bar;
+static struct mtx abc, def, ghi, jkl;
 static struct sx one, two, three, four;
 static struct lock fee, fi, fo, fum;
 
@@ -99,6 +100,19 @@
 
 /* Events. */
 
+static struct mtx *mtxen[] = { &abc, &def, &ghi, &jkl };
+
+static void
+mtx_deadlock(int thread)
+{
+
+	mtx_lock(mtxen[thread % 4]);
+	tsleep(mtxen, 0, "mtx_dead", hz/10);
+	mtx_lock(mtxen[(thread + 1) % 4]);
+}
+CRASH2_EVENT("mutex cycle", mtx_deadlock, mtx_deadlock, mtx_deadlock,
+    mtx_deadlock);
+
 static struct lock *locks[] = { &fee, &fi, &fo, &fum };
 static struct sx *sxs[] = { &one, &two, &three, &four };
 
@@ -124,7 +138,7 @@
 {
 
 	lockmgr(locks[thread % 4], LK_EXCLUSIVE, NULL, curthread);
-	tsleep(sxs, 0, "lk_dead", hz/10);
+	tsleep(locks, 0, "lk_dead", hz/10);
 	lockmgr(locks[(thread + 1) % 4], LK_EXCLUSIVE, NULL, curthread);
 }
 CRASH2_EVENT("lockmgr cycle", lockmgr_deadlock, lockmgr_deadlock,
@@ -367,6 +381,10 @@
 
 	rw_init(&foo, "foo");
 	mtx_init(&bar, "bar", NULL, MTX_DEF);
+	mtx_init(&abc, "abc", NULL, MTX_DEF);
+	mtx_init(&def, "def", NULL, MTX_DEF);
+	mtx_init(&ghi, "ghi", NULL, MTX_DEF);
+	mtx_init(&jkl, "jkl", NULL, MTX_DEF);	
 	sx_init(&one, "one");
 	sx_init(&two, "two");
 	sx_init(&three, "three");
@@ -414,6 +432,10 @@
 	sx_destroy(&three);
 	sx_destroy(&two);
 	sx_destroy(&one);
+	mtx_destroy(&jkl);
+	mtx_destroy(&ghi);
+	mtx_destroy(&def);
+	mtx_destroy(&abc);
 	mtx_destroy(&bar);
 	rw_destroy(&foo);
 	return (0);