Re: [PATCH] cpufreq : powernv: Report Pmax throttling if capped below nominal frequency

From: Viresh Kumar
Date: Mon Sep 14 2015 - 03:06:32 EST


On 14-09-15, 10:47, Shilpasri G Bhat wrote:
> Log a 'critical' message if the max frequency is reduced below nominal
> frequency. We already log 'info' message if the max frequency is
> capped below turbo frequency. CPU should guarantee atleast nominal
> frequency, but not turbo frequency in all system configurations and
> environments. So report the pmax throttling with severity when Pmax is
> dipped below nominal frequency.
>
> Signed-off-by: Shilpasri G Bhat <shilpa.bhat@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/cpufreq/powernv-cpufreq.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
> index 64994e1..2d9ed42 100644
> --- a/drivers/cpufreq/powernv-cpufreq.c
> +++ b/drivers/cpufreq/powernv-cpufreq.c
> @@ -327,8 +327,13 @@ static void powernv_cpufreq_throttle_check(void *data)
> if (chips[i].throttled)
> goto next;
> chips[i].throttled = true;
> - pr_info("CPU %d on Chip %u has Pmax reduced to %d\n", cpu,
> - chips[i].id, pmsr_pmax);
> + if (pmsr_pmax < powernv_pstate_info.nominal)
> + pr_crit("CPU %d on Chip %u has Pmax reduced to %d\n",
> + cpu, chips[i].id, pmsr_pmax);
> + else
> + pr_info("CPU %d on Chip %u has Pmax reduced to %d\n",
> + cpu, chips[i].id, pmsr_pmax);

I think the messages here can be improved a bit here to something
like:

pr_warn("CPU %d on Chip %u has Pmax reduced below nominal freq (%d < %d)\n",
cpu, chips[i].id, pmsr_pmax, powernv_pstate_info.nominal);

And similarly for the pr_info case as well.

--
viresh
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