Re: [RESEND PATCH] acpi-cpufreq: get the cur_freq from acpi_processor_performance states

From: Rafael J. Wysocki
Date: Fri Sep 26 2014 - 19:01:56 EST


On Thursday, August 21, 2014 01:55:15 PM Wang Weidong wrote:
> As the initialized freq_tables maybe different from the p-states
> values, so the array index is different as well.
>
> p-states value: [2400 2400 2000 ...], while the freq_tables:
> [2400 2000 ... CPUFREQ_TABLE_END]. After setted the freqs 2000,
> the perf->state is 3 while the freqs_table's index should be 2.
> So when call the get_cur_freq_on_cpu, the freqs value we get
> is 2400.
>
> So, fix the problem with the correct tables.

What you're saying is basically that freq_table and perf->states
diverge at one point. Shouldn't we re-generate freq_table in that
case instead of fixing up get_cur_freq_on_cpu() only in a quite
indirect way?

> Signed-off-by: Wang Weidong <wangweidong1@xxxxxxxxxx>
> ---
> drivers/cpufreq/acpi-cpufreq.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
> index b0c18ed..ac93885 100644
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -365,6 +365,7 @@ static u32 get_cur_val(const struct cpumask *mask)
> static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
> {
> struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
> + struct acpi_processor_performance *perf;
> unsigned int freq;
> unsigned int cached_freq;
>
> @@ -375,7 +376,8 @@ static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
> return 0;
> }
>
> - cached_freq = data->freq_table[data->acpi_data->state].frequency;
> + perf = data->acpi_data;
> + cached_freq = perf->states[perf->state].core_frequency * 1000;
> freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
> if (freq != cached_freq) {
> /*
>

--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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