Hi, The timing of this is not perfect (sorry about that), but here's a refresh of this series.
The majority of the previous cover letter still applies: On Monday, December 7, 2020 5:25:38 PM CET Rafael J. Wysocki wrote: > > This is based on the RFC posted a few days ago: > > https://lore.kernel.org/linux-pm/1817571.2o5Kk4Ohv2@kreacher/ > > Using intel_pstate in the passive mode with HWP enabled, in particular under > the schedutil governor, is still kind of problematic, because it has to > assume > that it should not allow the frequency to fall below the one requested by the > governor. For this reason, it translates the target frequency into > HWP.REQ.MIN > which generally causes the processor to run a bit too fast. > > Moreover, this allows the HWP algorithm to use any frequency between the > target > one and HWP.REQ.MAX that corresponds to the policy max limit and some > workloads > cause it to go for the max turbo frequency prematurely which hurts energy- > efficiency without improving performance, even though the schedutil governor > itself would not allow the frequency to ramp up so fast. > > This patch series attempts to improve the situation by introducing a new > driver > callback allowing the driver to receive more information from the governor. > In > particular, this allows the min (required) and target (desired) performance > levels to be passed to it and those can be used to give better hints to the > hardware. In this second revision there are three patches (one preparatory patch for schedutil that hasn't changed since the v1, the introduction of the new callback and schedutil changes in patch [2/3] and the intel_pstate changes in patch [3/3] that are the same as before. Please see patch changelogs for details. Thanks!
