[PATCH v4 09/16] PM / devfreq: tegra: Avoid inconsistency of current frequency value

Dmitry Osipenko
2019-05-01T23:42:53Z

The frequency value potentially could change in-between. It doesn't
cause any real problem at all right now, but that could change in the
future. Hence let's avoid the inconsistency.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/devfreq/tegra-devfreq.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c
index ea0da05cd7f2..5265d735419f 100644
--- a/drivers/devfreq/tegra-devfreq.c
+++ b/drivers/devfreq/tegra-devfreq.c
@@ -509,13 +509,15 @@ static int tegra_devfreq_get_dev_status(struct device *dev,
{
struct tegra_devfreq *tegra = dev_get_drvdata(dev);
struct tegra_devfreq_device *actmon_dev;
+ unsigned long cur_freq;

- stat->current_frequency = tegra->cur_freq * KHZ;
+ cur_freq = READ_ONCE(tegra->cur_freq);

/* To be used by the tegra governor */
stat->private_data = tegra;

/* The below are to be used by the other governors */
+ stat->current_frequency = cur_freq * KHZ;

actmon_dev = &tegra->devices[MCALL];

@@ -526,7 +528,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev,
stat->busy_time *= 100 / BUS_SATURATION_RATIO;

/* Number of cycles in a sampling period */
- stat->total_time = ACTMON_SAMPLING_PERIOD * tegra->cur_freq;
+ stat->total_time = ACTMON_SAMPLING_PERIOD * cur_freq;

stat->busy_time = min(stat->busy_time, stat->total_time);

--
2.21.0