Re: [PATCH V6 3/7] cpufreq: amd-pstate: Enable amd-pstate preferred core supporting.

From: Peter Zijlstra
Date: Sat Sep 09 2023 - 13:59:25 EST


On Fri, Sep 08, 2023 at 03:46:49PM +0800, Meng Li wrote:
> +static void amd_pstate_init_prefcore(void)
> +{
> + int cpu, ret;
> + u64 highest_perf;
> +
> + if (!prefcore)
> + return;
> +
> + for_each_online_cpu(cpu) {
> + ret = amd_pstate_get_highest_perf(cpu, &highest_perf);
> + if (ret)
> + break;
> +
> + sched_set_itmt_core_prio(highest_perf, cpu);
> +
> + /* check if CPPC preferred core feature is enabled*/
> + if (highest_perf == AMD_PSTATE_MAX_CPPC_PERF) {
> + pr_debug("AMD CPPC preferred core is unsupported!\n");
> + hw_prefcore = false;
> + prefcore = false;
> + return;
> + }
> + }
> +
> + /*
> + * This code can be run during CPU online under the
> + * CPU hotplug locks, so sched_set_amd_prefcore_support()
> + * cannot be called from here. Queue up a work item
> + * to invoke it.
> + */
> + schedule_work(&sched_prefcore_work);
> +}

Brilliant, repost without addressing prior feedback.. :-(