On Fri, May 20, 2022 at 9:25 AM T.J. Mercier <tjmercier@xxxxxxxxxx> wrote: > > On Fri, May 20, 2022 at 12:47 AM Tejun Heo <tj@xxxxxxxxxx> wrote: > > > > Hello, > > > > On Tue, May 17, 2022 at 04:30:29PM -0700, T.J. Mercier wrote: > > > Thanks for your suggestion. This almost works. "dmabuf" as a key could > > > work, but I'd actually like to account for each heap. Since heaps can > > > be dynamically added, I can't accommodate every potential heap name by > > > hardcoding registrations in the misc controller. > > > > On its own, that's a pretty weak reason to be adding a separate gpu > > controller especially given that it doesn't really seem to be one with > > proper abstractions for gpu resources. We don't want to keep adding random > > keys to misc controller but can definitely add limited flexibility. What > > kind of keys do you need? > > > Well the dmabuf-from-heaps component of this is the initial use case. > I was envisioning we'd have additional keys as discussed here: > https://lore.kernel.org/lkml/20220328035951.1817417-1-tjmercier@xxxxxxxxxx/T/#m82e5fe9d8674bb60160701e52dae4356fea2ddfa > So we'd end up with a well-defined core set of keys like "system", and > then drivers would be free to use their own keys for their own unique > purposes which could be complementary or orthogonal to the core set. > Yesterday I was talking with someone who is interested in limiting gpu > cores and bus IDs in addition to gpu memory. How to define core keys > is the part where it looks like there's trouble. > > For my use case it would be sufficient to have current and maximum > values for an arbitrary number of keys - one per heap. So the only > part missing from the misc controller (for my use case) is the ability > to register a new key at runtime as heaps are added. Instead of > keeping track of resources with enum misc_res_type, requesting a > resource handle/ID from the misc controller at runtime is what I think > would be required instead. > Quick update: I'm going to make an attempt to modify the misc controller to support a limited amount of dynamic resource registration/tracking in place of the new controller in this series. Thanks everyone for the feedback. -T.J. > > Thanks. > > > > -- > > tejun
