Hello, Tao. On Tue, 08 Sep 2026 18:01:35 +0800, Tao Cui wrote:
> 4. One model system-wide vs named models selectable per device (as > tcp-cc names are per-socket)? The struct_ops instance should be per-device. Loading a model for a device should switch it to BPF automatically. Switching back to the builtin model should detach the struct_ops. > 2. Per-cgroup state lifetime: iocg_id is the css id and is recycled > once the cgroup is removed, so models must treat it as a > transient key. Does the interface need a release(iocg_id) > callback so models can clean up per-cgroup state instead of > detecting reuse, or is per-cgroup bpf local storage, which > carries its own lifetime, the better home for model state? I'd pass blkcg as a kptr and add online/offline callbacks so the model can manage its per-cgroup state. > return value of 0 delegates the IO back to the builtin formula, so a > model which only handles some IO types cannot make the rest free. I don't think mixing BPF and builtin pricing makes sense, either per IO or between charging and request sizing. It seems convoluted and error-prone. Implementing the linear model in BPF is straightforward. Please combine the interface, registration, dispatch and configuration changes into one patch. These patches are small and implement one feature. Thanks. -- tejun
