refscale: Provide for initialization failure

Current tests all have init() functions that are guaranteed to succeed.
But upcoming tests will need to allocate memory, thus possibly failing.
This commit therefore handles init() function failure.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

kernel/rcu/refscale.c

@@ -124,7 +124,7 @@ static int exp_idx;
 
 // Operations vector for selecting different types of tests.
 struct ref_scale_ops {
-	void (*init)(void);
+	bool (*init)(void);
 	void (*cleanup)(void);
 	void (*readsection)(const int nloops);
 	void (*delaysection)(const int nloops, const int udl, const int ndl);
@@ -162,8 +162,9 @@ static void ref_rcu_delay_section(const int nloops, const int udl, const int ndl
 	}
 }
 
-static void rcu_sync_scale_init(void)
+static bool rcu_sync_scale_init(void)
 {
+	return true;
 }
 
 static struct ref_scale_ops rcu_ops = {
@@ -315,9 +316,10 @@ static struct ref_scale_ops refcnt_ops = {
 // Definitions for rwlock
 static rwlock_t test_rwlock;
 
-static void ref_rwlock_init(void)
+static bool ref_rwlock_init(void)
 {
 	rwlock_init(&test_rwlock);
+	return true;
 }
 
 static void ref_rwlock_section(const int nloops)
@@ -351,9 +353,10 @@ static struct ref_scale_ops rwlock_ops = {
 // Definitions for rwsem
 static struct rw_semaphore test_rwsem;
 
-static void ref_rwsem_init(void)
+static bool ref_rwsem_init(void)
 {
 	init_rwsem(&test_rwsem);
+	return true;
 }
 
 static void ref_rwsem_section(const int nloops)
@@ -833,7 +836,10 @@ ref_scale_init(void)
 		goto unwind;
 	}
 	if (cur_ops->init)
-		cur_ops->init();
+		if (!cur_ops->init()) {
+			firsterr = -EUCLEAN;
+			goto unwind;
+		}
 
 	ref_scale_print_module_parms(cur_ops, "Start of test");