Re: [PATCH v7 17/19] PM / devfreq: tegra30: Support variable polling interval

From: Michał Mirosław
Date: Fri Nov 01 2019 - 17:58:21 EST


On Wed, Oct 30, 2019 at 01:00:17AM +0300, Dmitry Osipenko wrote:
> The ACTMON governor is interrupt-driven and currently hardware's polling
> interval is fixed to 16ms in the driver. Devfreq supports variable polling
> interval by the generic governors, let's re-use the generic interface for
> changing of the polling interval. Now the polling interval can be changed
> dynamically via /sys/class/devfreq/devfreq0/polling_interval.
[...]
> @@ -308,7 +308,7 @@ static unsigned long actmon_device_target_freq(struct tegra_devfreq *tegra,
> unsigned int avg_sustain_coef;
> unsigned long target_freq;
>
> - target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD;
> + target_freq = dev->avg_count / tegra->devfreq->profile->polling_ms;
> avg_sustain_coef = 100 * 100 / dev->config->boost_up_threshold;
> target_freq = do_percent(target_freq, avg_sustain_coef);
> target_freq += dev->boost_freq;

Noting a comment in patch 13, if this is hot path you could try reciprocal_divide().

Best Regards,
Michał Mirosław