[PATCH AUTOSEL 5.5 269/542] PM / devfreq: Change time stats to 64-bit

From: Sasha Levin
Date: Fri Feb 14 2020 - 10:54:55 EST


From: Kamil Konieczny <k.konieczny@xxxxxxxxxxx>

[ Upstream commit b76b3479dab948bea0a98b6d263eb56d8f358528 ]

Change time stats counting to bigger type by using 64-bit jiffies.
This will make devfreq stats code look similar to cpufreq stats and
prevents overflow (for HZ = 1000 after 49.7 days).

Signed-off-by: Kamil Konieczny <k.konieczny@xxxxxxxxxxx>
Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/devfreq/devfreq.c | 14 +++++++-------
include/linux/devfreq.h | 4 ++--
2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 07602083c743e..554d155106a5f 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -209,10 +209,10 @@ static int set_freq_table(struct devfreq *devfreq)
int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
{
int lev, prev_lev, ret = 0;
- unsigned long cur_time;
+ u64 cur_time;

lockdep_assert_held(&devfreq->lock);
- cur_time = jiffies;
+ cur_time = get_jiffies_64();

/* Immediately exit if previous_freq is not initialized yet. */
if (!devfreq->previous_freq)
@@ -535,7 +535,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
msecs_to_jiffies(devfreq->profile->polling_ms));

out_update:
- devfreq->last_stat_updated = jiffies;
+ devfreq->last_stat_updated = get_jiffies_64();
devfreq->stop_polling = false;

if (devfreq->profile->get_cur_freq &&
@@ -820,7 +820,7 @@ struct devfreq *devfreq_add_device(struct device *dev,

devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
devfreq->profile->max_state,
- sizeof(unsigned long),
+ sizeof(*devfreq->time_in_state),
GFP_KERNEL);
if (!devfreq->time_in_state) {
mutex_unlock(&devfreq->lock);
@@ -828,7 +828,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
goto err_devfreq;
}

- devfreq->last_stat_updated = jiffies;
+ devfreq->last_stat_updated = get_jiffies_64();

srcu_init_notifier_head(&devfreq->transition_notifier_list);

@@ -1589,8 +1589,8 @@ static ssize_t trans_stat_show(struct device *dev,
for (j = 0; j < max_state; j++)
len += sprintf(buf + len, "%10u",
devfreq->trans_table[(i * max_state) + j]);
- len += sprintf(buf + len, "%10u\n",
- jiffies_to_msecs(devfreq->time_in_state[i]));
+ len += sprintf(buf + len, "%10llu\n", (u64)
+ jiffies64_to_msecs(devfreq->time_in_state[i]));
}

len += sprintf(buf + len, "Total transition : %u\n",
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index fb376b5b72819..95816a8e3d266 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -177,8 +177,8 @@ struct devfreq {
/* information for device frequency transition */
unsigned int total_trans;
unsigned int *trans_table;
- unsigned long *time_in_state;
- unsigned long last_stat_updated;
+ u64 *time_in_state;
+ u64 last_stat_updated;

struct srcu_notifier_head transition_notifier_list;

--
2.20.1