maple_tree: update check_forking() and bench_forking()

Updated check_forking() and bench_forking() to use __mt_dup() to duplicate
maple tree.

Link: https://lkml.kernel.org/r/20231027033845.90608-9-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

tools/include/linux/rwsem.h

@@ -37,4 +37,8 @@ static inline int up_write(struct rw_semaphore *sem)
 {
 	return pthread_rwlock_unlock(&sem->lock);
 }
+
+#define down_read_nested(sem, subclass)		down_read(sem)
+#define down_write_nested(sem, subclass)	down_write(sem)
+
 #endif /* _TOOLS_RWSEM_H */