lock_downgrade 378 include/linux/lockdep.h extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip); lock_downgrade 4470 kernel/locking/lockdep.c EXPORT_SYMBOL_GPL(lock_downgrade); lock_downgrade 1596 kernel/locking/rwsem.c lock_downgrade(&sem->dep_map, _RET_IP_);