On Sun, Jun 15, 2025 at 5:24 PM Tingmao Wang <m@xxxxxxxxxx> wrote: [...] > > > > I would not want it in the first place. But I have a deep seated > > aversion to exposing two different variants. > > Hi Christian, Jan, Song, > > I do appreciate your thoughts here and thanks for taking the time to > explain. I just have some specific points which I would like you to > consider: > > Taking a step back, maybe the specific designs need a bit more thought, > but are you at all open to the idea of letting other subsystems take > advantage of a rcu-based parent walk? I cannot really speak for VFS folks, but I guess rcu-based parent walk out of fs/ is not preferred. > Testing shows that for specific > cases of a deep directory hierarchy the speedup (for time in Landlock) can > be almost 60%, and still very significant for the average case. [1] [...] > I'm happy to wait till Song's current patch is finished before continuing > this, but if there is strong objection to two separate APIs, I would > really appreciate if we can end up in a state where further change to > implement this is possible. In v5, path_walk_parent API is not exported. We can easily change it in the future. Therefore, I don't think we need to rush into a rcu-walk design before landing path_walk_parent. Thanks, Song [...]
