added new lock test to check do i hold functionality. tested on incorrect implementation, fails. tested on correct implementation, passed.

kern/test/synchtest.c

@@ -238,6 +238,29 @@ fail2:
 	return;
 }
 
+static
+void
+locktestthread2(void *junk, unsigned long num)
+{
+    (void)junk;
+
+    if(num == 0){
+        lock_acquire(testlock);
+    }
+    else{
+        if(lock_do_i_hold(testlock)){
+            goto fail;
+        }
+    }
+
+    V(donesem);
+    return;
+
+fail:
+    failif(true);
+    V(donesem);
+    return;
+}
 
 int
 locktest(int nargs, char **args)
@@ -314,7 +337,7 @@ locktest2(int nargs, char **args) {
 
 	return 0;
 }
-
+    
 int
 locktest3(int nargs, char **args) {
 	(void)nargs;
@@ -341,6 +364,51 @@ locktest3(int nargs, char **args) {
 	return 0;
 }
 
+int 
+locktest4(int nargs, char **args) {
+    (void) nargs;
+    (void) args;
+
+    kprintf_n("Starting lt4...\n");
+    
+    test_status = TEST161_SUCCESS;
+
+    testlock = lock_create("testlock");
+    if(testlock == NULL) {
+        panic("lt4: lock_create failed\n");
+    }
+
+    donesem = sem_create("donesem", 0);
+    if (donesem == NULL) {
+        lock_destroy(testlock);
+		panic("lt1: sem_create failed\n");
+	}
+
+    int i, result;
+	for (i=0; i<2; i++) {
+		kprintf_t(".");
+		result = thread_fork("lt4", NULL, locktestthread2, NULL, i);
+		if (result) {
+			panic("lt1: thread_fork failed: %s\n", strerror(result));
+		}
+	}
+
+    for(i=0; i<2; i++) {
+        kprintf_t(".");
+        P(donesem);
+    }
+    
+    lock_destroy(testlock);
+    sem_destroy(donesem);
+	testlock = NULL;
+    donesem = NULL;
+
+	kprintf_t("\n");
+	success(test_status, SECRET, "lt1");
+
+    return 0;
+}
+
 static
 void
 cvtestthread(void *junk, unsigned long num)