- find_lock_in_path() tries to find whether a lock class is in the path. - find_next_dep_in_path() returns the next dependency after a given dependency in the path.
Signed-off-by: Yuyang Du <duyuy...@gmail.com> --- kernel/locking/lockdep.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 1805017..9fa38fb 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1463,6 +1463,37 @@ static inline int get_lock_depth(struct lock_list *child) } /* + * Return the dependency if @lock is in the path, otherwise NULL. + */ +static inline struct lock_list * +find_lock_in_path(struct lock_class *lock, struct lock_list *target) +{ + while ((target = get_lock_parent(target))) + if (fw_dep_class(target) == lock) + return target; + + return NULL; +} + +/* + * Walk back to the next dependency after @source from @target. Note + * that @source must be in the path, and @source can not be the same as + * @target, otherwise this is going to fail and reutrn NULL. + */ +static inline struct lock_list * +find_next_dep_in_path(struct lock_list *source, struct lock_list *target) +{ + while (get_lock_parent(target) != source) { + target = get_lock_parent(target); + + if (!target) + break; + } + + return target; +} + +/* * Return the forward or backward dependency list. * * @lock: the lock_list to get its class's dependency list -- 1.8.3.1