Re: [PATCH] cpufreq: use last policy after online

Rafael J. Wysocki
2015-12-02T22:51:46Z

On Wednesday, December 02, 2015 08:56:45 AM Srinivas Pandruvada wrote:
> On Wed, 2015-12-02 at 08:23 +0530, Viresh Kumar wrote:
> > On 01-12-15, 16:52, Srinivas Pandruvada wrote:
> > > For cpufreq drivers which use setpolicy interface, after offline->online
> > > the policy is set to default. This can be reproduced by setting the
> > > default policy of intel_pstate or longrun to ondemand and then change to
> > > "performance". After offline and online, the setpolicy will be called with
> > > the policy=ondemand.
> > > For drivers using governors this condition is handled by storing
> > > last_governor, during offline and restoring during online. The same should
> > > be done for drivers using setpolicy interface. Storing last_policy during
> > > offline and restoring during online.
> > >
> > > Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> > > ---
> > > drivers/cpufreq/cpufreq.c | 14 ++++++++++----
> > > include/linux/cpufreq.h | 1 +
> > > 2 files changed, 11 insertions(+), 4 deletions(-)
> >
> > Okay, the problem looks real. But I think it should be solved a bit
> > differently.
> >
> > Try partly reverting the below commit, so that we can use user_policy
> > instead.
> We have to store somewhere. I can, but my approach matching what using
> governors do to store and restore policy. In this way we have consistent
> processing for has_target() and setpolicy() drivers.

Agreed, consistency matters.

OK, patch queued up for 4.4-rc, thanks!

Rafael