On 14/10/2020 17:00, Yun Hsiang wrote: > On Tue, Oct 13, 2020 at 10:25:48PM +0200, Dietmar Eggemann wrote: >> Hi Yun, >> >> On 12/10/2020 18:31, Yun Hsiang wrote:
[...] > The tg uclamp value may also change. If top-app's cpu.uclamp.min change > to 50 (~500), then task A's effective uclamp min value is 300 not ~500. > We can set task A's uclamp to 1024, it will be restricted by the tg. > But when task A move to root group, it's effective uclamp min value > will be 1024 not 0. If a task is in root group and it doesn't want to > control it's uclamp, the effective uclamp min value of that task should be 0. > So I think reset functionality is needed. OK, looks like the intended solution { a) or b) in https://lkml.kernel.org/r/87zh4ohnf9.derkl...@matbug.net} is not really feasible. So we do need the uclamp reset to enable throughout the entire lifetime of task p 'p is !user_defined -> p is controlled by taskgroup hierarchy)'.