On Wed, May 16, 2018 at 6:49 AM, Srinivas Pandruvada <[email protected]> wrote: > When a busy task migrates to a new CPU boost HWP prformance to max. This > helps workloads on servers with per core P-states, which saturates all > CPUs and then they migrate frequently. But changing limits has extra over > head of issuing new HWP Request MSR, which takes 1000+ > cycles. So this change limits setting HWP Request MSR. > Rate control in setting HWP Requests: > - If the current performance is around P1, simply ignore. > - Once set wait till hold time, till remove boost. While the boost > is on, another flags is notified, it will prolong boost. > - The task migrates needs to have some utilzation which is more > than threshold utilization, which will trigger P-state above minimum. > > Signed-off-by: Srinivas Pandruvada <[email protected]> > --- > drivers/cpufreq/intel_pstate.c | 37 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 36 insertions(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > index d418265..ec455af 100644 > --- a/drivers/cpufreq/intel_pstate.c > +++ b/drivers/cpufreq/intel_pstate.c > @@ -227,6 +227,7 @@ struct global_params { > * defines callback and arguments > * @hwp_boost_active: HWP performance is boosted on this CPU > * @last_io_update: Last time when IO wake flag was set > + * @migrate_hint: Set when scheduler indicates thread migration > * > * This structure stores per CPU instance data for all CPUs. > */ > @@ -263,6 +264,7 @@ struct cpudata { > call_single_data_t csd; > bool hwp_boost_active; > u64 last_io_update; > + bool migrate_hint;
Why do you need this in the struct? It looks like it only is used locally in intel_pstate_update_util_hwp(). > };
