Re: [PATCH for-4.22] Revert "xen/cpufreq: fix usages of align_timer() in the on-demand governor"

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 6/16/26 8:47 AM, Roger Pau Monné wrote:
> On Tue, Jun 16, 2026 at 08:30:25AM +0200, Jan Beulich wrote:
> > On 15.06.2026 21:39, Jason Andryuk wrote:
> > > The original commit showed a ~6% regression in a benchmark.  The call to
> > > align_timer(firsttick, period) rounds firsttick up to the next mutiple
> > > of the period, if firsttick % period != 0:
> > >
> > > align_timer(0, period)          -> 0
> > > align_timer(1, period)          -> period
> > > align_timer(period, period)     -> period
> > > align_timer(period + 1, period) -> 2 * period
> > >
> > > So adding the period (sampling_rate) before calling align_timer() will
> > > in most cases incease the expiration to 2 * period (sampling_rate) (the
> > > exception being firsttick % period == 0).  This longer timer slows the
> > > reaction time of the algorithm.
> > >
> > > This reverts commit a0ed5bcfbeee81c91c574ad484faa057054eaf09.
> > >
> > > Signed-off-by: Jason Andryuk <jason.andryuk@xxxxxxx>
> Acked-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
>
> Adding Oleksii for a release-ack.
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

Thanks.

~ Oleksii