Re: [RFC/RFT] [PATCH 08/10] cpufreq: intel_pstate: Dyanmically update busy pct
On Tue, May 15, 2018 at 09:49:09PM -0700, Srinivas Pandruvada wrote:
> +static inline void intel_pstate_update_busy_threshold(struct cpudata *cpu)
> +{
> + if (!hwp_boost_threshold_busy_pct) {
> + int min_freq, max_freq;
> +
> + min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
> + update_turbo_state();
> + max_freq = global.turbo_disabled || global.no_turbo ?
> + cpu->pstate.max_freq : cpu->pstate.turbo_freq;
> +
> + /*
> + * We are guranteed to get atleast min P-state.
If we assume
> + * P-state is proportional to load (such that 10% load
> + * increase will result in 10% P-state increase),
we will
> + * get at least min P-state till we have atleast
> + * (min * 100/max) percent cpu load.
turbo makes that story less clear ofcourse.
So any load less than
> + * than this this we shouldn't do any boost. Then boosting
> + * is not free, we will add atleast 20% offset.
This I don't get.. so you want to remain at min P longer?
> + */
> + hwp_boost_threshold_busy_pct = min_freq * 100 / max_freq;
> + hwp_boost_threshold_busy_pct += 20;
> + pr_debug("hwp_boost_threshold_busy_pct = %d\n",
> + hwp_boost_threshold_busy_pct);
> + }
> +}
And then this part should go in the previous patch.
Re: [RFC/RFT] [PATCH 08/10] cpufreq: intel_pstate: Dyanmically update busy pct
On Tue, May 15, 2018 at 09:49:09PM -0700, Srinivas Pandruvada wrote:
> +static inline void intel_pstate_update_busy_threshold(struct cpudata *cpu)
> +{
> + /* P1 percent out of total range of P-states */
> + if (cpu->pstate.max_freq != cpu->pstate.turbo_freq) {
> + hwp_boost_pstate_threshold =
> + cpu->pstate.max_freq * SCHED_CAPACITY_SCALE /
> cpu->pstate.turbo_freq;
> + pr_debug("hwp_boost_pstate_threshold = %d\n",
> + hwp_boost_pstate_threshold);
> + }
> +
> +}
> +
> static inline void intel_pstate_update_util_hwp(struct update_util_data
> *data,
> u64 time, unsigned int flags)
> {
> @@ -2061,8 +2097,10 @@ static int __intel_pstate_cpu_init(struct
> cpufreq_policy *policy)
>
> policy->fast_switch_possible = true;
>
> - if (hwp_active)
> + if (hwp_active) {
> csd_init(cpu);
> + intel_pstate_update_busy_threshold(cpu);
> + }
>
> return 0;
> }
This should go in patch #5 and then you can remove that SKX hack. Which
you left in, even though you now did it right.
