Hi,
this patch series tries to improve devfreq statistics:
- do conversion to use 64-bit jiffies for storing elapsed time and prevent
counters overflow,
- add ability to reset statistics using sysfs,
- move statistics data to separate structure for improved code
readability and maintenance.
Changes in v3:
- changed types of cur_time and last_stats_updated to u64 as this is
returned by get_jiffies_64() in 1/3
- add checks for zero in input and clear stats only when zero is written
to trans_stats
- change documentation of trans_stat in sysfs
- removed freq_table and max_state from struct devfreq_stats as they are
already present in struct devfreq_dev_profile
- renamed last_stat_updated to last_update, as 'stat' is already present
in struct devfreq_stats
- define struct devfreq_stats stats; in devfreq as there is only one
stats per devfreq
- improve descriptions of devfreq_stats and stats
- use profile instead of devfreq->profile in devfreq_add_device, as this
var is already parameter
- added Reviewed-by: Matthias Kaehlcke <[email protected]> to 3/3
Changes in v2:
- added Acked-by to first patch
- dropped spinlock patch, there is mutex used for protecting stats data
- rewrite clearing statistics, suggested by Chanwoo Choi: reuse
trans_stats sysfs file, any write to it will clear devfreq stats
- dropped change var name last_stat_updated
- squashed three last patches into one, as it turned out that freq_table
from devfreq_profile is used by other drivers
- rebased on linux-next
Kamil Konieczny (3):
devfreq: change time stats to 64-bit
devfreq: add clearing transitions stats
devfreq: move statistics to separate struct
Documentation/ABI/testing/sysfs-class-devfreq | 11 ++-
drivers/devfreq/devfreq.c | 92 ++++++++++++-------
include/linux/devfreq.h | 26 ++++--
3 files changed, 83 insertions(+), 46 deletions(-)
--
2.24.0
Count time and transitions between devfreq frequencies in separate struct
for improved code readability and maintenance.
Signed-off-by: Kamil Konieczny <[email protected]>
Reviewed-by: Matthias Kaehlcke <[email protected]>
---
Changes in v3:
- removed freq_table and max_state from struct devfreq_stats as they are
already present in struct devfreq_dev_profile
- renamed last_stat_updated to last_update, as 'stat' is already present
in struct devfreq_stats
- define struct devfreq_stats stats; in devfreq as there is only one
stats per devfreq
- improve descriptions of devfreq_stats and stats
- use profile instead of devfreq->profile in devfreq_add_device, as this
var is already parameter
- added Reviewed-by: Matthias Kaehlcke <[email protected]>
Changes in v2:
- squash three patches into one, do not modify devfreq_profile and separate stats
into devfreq_stats
---
drivers/devfreq/devfreq.c | 67 ++++++++++++++++++++-------------------
include/linux/devfreq.h | 26 +++++++++------
2 files changed, 51 insertions(+), 42 deletions(-)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 218eb64d7f28..bcd7e92d2cf3 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -198,6 +198,7 @@ static int set_freq_table(struct devfreq *devfreq)
*/
int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
{
+ struct devfreq_stats *stats = &devfreq->stats;
int lev, prev_lev, ret = 0;
u64 cur_time;
@@ -214,9 +215,7 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
goto out;
}
- devfreq->time_in_state[prev_lev] +=
- cur_time - devfreq->last_stat_updated;
-
+ stats->time_in_state[prev_lev] += cur_time - stats->last_update;
lev = devfreq_get_freq_level(devfreq, freq);
if (lev < 0) {
ret = lev;
@@ -224,13 +223,13 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
}
if (lev != prev_lev) {
- devfreq->trans_table[(prev_lev *
- devfreq->profile->max_state) + lev]++;
- devfreq->total_trans++;
+ stats->trans_table[(prev_lev * devfreq->profile->max_state) +
+ lev]++;
+ stats->total_trans++;
}
out:
- devfreq->last_stat_updated = cur_time;
+ stats->last_update = cur_time;
return ret;
}
EXPORT_SYMBOL(devfreq_update_status);
@@ -525,7 +524,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
msecs_to_jiffies(devfreq->profile->polling_ms));
out_update:
- devfreq->last_stat_updated = get_jiffies_64();
+ devfreq->stats.last_update = get_jiffies_64();
devfreq->stop_polling = false;
if (devfreq->profile->get_cur_freq &&
@@ -735,28 +734,29 @@ struct devfreq *devfreq_add_device(struct device *dev,
goto err_out;
}
- devfreq->trans_table = devm_kzalloc(&devfreq->dev,
+ devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev,
array3_size(sizeof(unsigned int),
- devfreq->profile->max_state,
- devfreq->profile->max_state),
+ profile->max_state,
+ profile->max_state),
GFP_KERNEL);
- if (!devfreq->trans_table) {
+ if (!devfreq->stats.trans_table) {
mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_devfreq;
}
- devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
- devfreq->profile->max_state,
- sizeof(*devfreq->time_in_state),
+ devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev,
+ profile->max_state,
+ sizeof(*devfreq->stats.time_in_state),
GFP_KERNEL);
- if (!devfreq->time_in_state) {
+ if (!devfreq->stats.time_in_state) {
mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_devfreq;
}
- devfreq->last_stat_updated = get_jiffies_64();
+ devfreq->stats.last_update = get_jiffies_64();
+ devfreq->stats.total_trans = 0;
srcu_init_notifier_head(&devfreq->transition_notifier_list);
@@ -1435,9 +1435,11 @@ static ssize_t trans_stat_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct devfreq *devfreq = to_devfreq(dev);
+ struct devfreq_stats *stats = &devfreq->stats;
+ unsigned int max_state = devfreq->profile->max_state;
+ unsigned long *freq_table = devfreq->profile->freq_table;
ssize_t len;
int i, j;
- unsigned int max_state = devfreq->profile->max_state;
if (max_state == 0)
return sprintf(buf, "Not Supported.\n");
@@ -1453,29 +1455,27 @@ static ssize_t trans_stat_show(struct device *dev,
len = sprintf(buf, " From : To\n");
len += sprintf(buf + len, " :");
for (i = 0; i < max_state; i++)
- len += sprintf(buf + len, "%10lu",
- devfreq->profile->freq_table[i]);
+ len += sprintf(buf + len, "%10lu", freq_table[i]);
len += sprintf(buf + len, " time(ms)\n");
for (i = 0; i < max_state; i++) {
- if (devfreq->profile->freq_table[i]
- == devfreq->previous_freq) {
+ if (freq_table[i] == devfreq->previous_freq)
len += sprintf(buf + len, "*");
- } else {
+ else
len += sprintf(buf + len, " ");
- }
- len += sprintf(buf + len, "%10lu:",
- devfreq->profile->freq_table[i]);
+
+ len += sprintf(buf + len, "%10lu:", freq_table[i]);
for (j = 0; j < max_state; j++)
len += sprintf(buf + len, "%10u",
- devfreq->trans_table[(i * max_state) + j]);
+ stats->trans_table[(i * max_state) + j]);
+
len += sprintf(buf + len, "%10llu\n", (u64)
- jiffies64_to_msecs(devfreq->time_in_state[i]));
+ jiffies64_to_msecs(stats->time_in_state[i]));
}
len += sprintf(buf + len, "Total transition : %u\n",
- devfreq->total_trans);
+ stats->total_trans);
return len;
}
@@ -1484,6 +1484,7 @@ static ssize_t trans_stat_store(struct device *dev,
const char *buf, size_t count)
{
struct devfreq *df = to_devfreq(dev);
+ struct devfreq_stats *stats = &df->stats;
unsigned int cnt = df->profile->max_state;
int err, value;
@@ -1495,10 +1496,10 @@ static ssize_t trans_stat_store(struct device *dev,
return count;
mutex_lock(&df->lock);
- memset(df->time_in_state, 0, cnt * sizeof(u64));
- memset(df->trans_table, 0, cnt * cnt * sizeof(int));
- df->last_stat_updated = get_jiffies_64();
- df->total_trans = 0;
+ memset(stats->time_in_state, 0, cnt * sizeof(u64));
+ memset(stats->trans_table, 0, cnt * cnt * sizeof(int));
+ stats->last_update = get_jiffies_64();
+ stats->total_trans = 0;
mutex_unlock(&df->lock);
return count;
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 41f15e7a22b8..de2fdc56aa5b 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -106,6 +106,20 @@ struct devfreq_dev_profile {
unsigned int max_state;
};
+/**
+ * struct devfreq_stats - Statistics of devfreq device behavior
+ * @total_trans: Number of devfreq transitions.
+ * @trans_table: Statistics of devfreq transitions.
+ * @time_in_state: Statistics of devfreq states.
+ * @last_update: The last time stats were updated.
+ */
+struct devfreq_stats {
+ unsigned int total_trans;
+ unsigned int *trans_table;
+ u64 *time_in_state;
+ u64 last_update;
+};
+
/**
* struct devfreq - Device devfreq structure
* @node: list node - contains the devices with devfreq that have been
@@ -131,10 +145,7 @@ struct devfreq_dev_profile {
* @suspend_freq: frequency of a device set during suspend phase.
* @resume_freq: frequency of a device set in resume phase.
* @suspend_count: suspend requests counter for a device.
- * @total_trans: Number of devfreq transitions
- * @trans_table: Statistics of devfreq transitions
- * @time_in_state: Statistics of devfreq states
- * @last_stat_updated: The last time stat updated
+ * @stats: Statistics of devfreq device behavior
* @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
*
* This structure stores the devfreq information for a give device.
@@ -171,11 +182,8 @@ struct devfreq {
unsigned long resume_freq;
atomic_t suspend_count;
- /* information for device frequency transition */
- unsigned int total_trans;
- unsigned int *trans_table;
- u64 *time_in_state;
- u64 last_stat_updated;
+ /* information for device frequency transitions */
+ struct devfreq_stats stats;
struct srcu_notifier_head transition_notifier_list;
};
--
2.24.0
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 <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
---
Changes in v3:
- changed types of cur_time and last_stats_updated to u64 as this is
returned by get_jiffies_64()
Changes in v2:
- added Acked-by, rebased on linux-next
---
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 bdeb4189c978..abecadeb3dc2 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -199,10 +199,10 @@ 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)
@@ -525,7 +525,7 @@ 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 &&
@@ -748,7 +748,7 @@ 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);
@@ -756,7 +756,7 @@ 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);
@@ -1470,8 +1470,8 @@ 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 2bae9ed3c783..41f15e7a22b8 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -174,8 +174,8 @@ 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;
};
--
2.24.0
On 12/5/19 11:55 PM, Kamil Konieczny wrote:
> 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 <[email protected]>
> Acked-by: Chanwoo Choi <[email protected]>
> ---
> Changes in v3:
> - changed types of cur_time and last_stats_updated to u64 as this is
> returned by get_jiffies_64()
>
> Changes in v2:
> - added Acked-by, rebased on linux-next
> ---
> 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 bdeb4189c978..abecadeb3dc2 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -199,10 +199,10 @@ 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)
> @@ -525,7 +525,7 @@ 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 &&
> @@ -748,7 +748,7 @@ 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);
> @@ -756,7 +756,7 @@ 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);
>
> @@ -1470,8 +1470,8 @@ 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 2bae9ed3c783..41f15e7a22b8 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -174,8 +174,8 @@ 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;
> };
>
Applied it. Thanks.
--
Best Regards,
Chanwoo Choi
Samsung Electronics
From: Kamil Konieczny <[email protected]>
Add clearing transition table and time in states devfreq statistics
by writing 0 (zero) to trans_stat file in devfreq sysfs. An example use
is like following:
echo 0 > /sys/class/devfreq/devfreqX/trans_stat
Signed-off-by: Kamil Konieczny <[email protected]>
[cw00.choi: Edit return value if entering the wrong value for reset
and use arrary3_size() to get the size of 3-dimensional array]
Signed-off-by: Chanwoo Choi <[email protected]>
---
Documentation/ABI/testing/sysfs-class-devfreq | 11 ++++---
drivers/devfreq/devfreq.c | 29 ++++++++++++++++++-
2 files changed, 35 insertions(+), 5 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq
index 75897e2fde43..9758eb85ade3 100644
--- a/Documentation/ABI/testing/sysfs-class-devfreq
+++ b/Documentation/ABI/testing/sysfs-class-devfreq
@@ -55,12 +55,15 @@ What: /sys/class/devfreq/.../trans_stat
Date: October 2012
Contact: MyungJoo Ham <[email protected]>
Description:
- This ABI shows the statistics of devfreq behavior on a
- specific device. It shows the time spent in each state and
- the number of transitions between states.
+ This ABI shows or clears the statistics of devfreq behavior
+ on a specific device. It shows the time spent in each state
+ and the number of transitions between states.
In order to activate this ABI, the devfreq target device
driver should provide the list of available frequencies
- with its profile.
+ with its profile. If need to reset the statistics of devfreq
+ behavior on a specific device, enter 0(zero) to 'trans_stat'
+ as following:
+ echo 0 > /sys/class/devfreq/.../trans_stat
What: /sys/class/devfreq/.../userspace/set_freq
Date: September 2011
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index abecadeb3dc2..df31f430051d 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -1478,7 +1478,34 @@ static ssize_t trans_stat_show(struct device *dev,
devfreq->total_trans);
return len;
}
-static DEVICE_ATTR_RO(trans_stat);
+
+static ssize_t trans_stat_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct devfreq *df = to_devfreq(dev);
+ int err, value;
+
+ if (df->profile->max_state == 0)
+ return count;
+
+ err = kstrtoint(buf, 10, &value);
+ if (err || value != 0)
+ return -EINVAL;
+
+ mutex_lock(&df->lock);
+ memset(df->time_in_state, 0, (df->profile->max_state *
+ sizeof(*df->time_in_state)));
+ memset(df->trans_table, 0, array3_size(sizeof(unsigned int),
+ df->profile->max_state,
+ df->profile->max_state));
+ df->total_trans = 0;
+ df->last_stat_updated = get_jiffies_64();
+ mutex_unlock(&df->lock);
+
+ return count;
+}
+static DEVICE_ATTR_RW(trans_stat);
static struct attribute *devfreq_attrs[] = {
&dev_attr_name.attr,
--
2.17.1
On 12/6/19 11:18 AM, Chanwoo Choi wrote:
> From: Kamil Konieczny <[email protected]>
>
> Add clearing transition table and time in states devfreq statistics
> by writing 0 (zero) to trans_stat file in devfreq sysfs. An example use
> is like following:
>
> echo 0 > /sys/class/devfreq/devfreqX/trans_stat
>
> Signed-off-by: Kamil Konieczny <[email protected]>
> [cw00.choi: Edit return value if entering the wrong value for reset
> and use arrary3_size() to get the size of 3-dimensional array]
> Signed-off-by: Chanwoo Choi <[email protected]>
> ---
> Documentation/ABI/testing/sysfs-class-devfreq | 11 ++++---
> drivers/devfreq/devfreq.c | 29 ++++++++++++++++++-
> 2 files changed, 35 insertions(+), 5 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq
> index 75897e2fde43..9758eb85ade3 100644
> --- a/Documentation/ABI/testing/sysfs-class-devfreq
> +++ b/Documentation/ABI/testing/sysfs-class-devfreq
> @@ -55,12 +55,15 @@ What: /sys/class/devfreq/.../trans_stat
> Date: October 2012
> Contact: MyungJoo Ham <[email protected]>
> Description:
> - This ABI shows the statistics of devfreq behavior on a
> - specific device. It shows the time spent in each state and
> - the number of transitions between states.
> + This ABI shows or clears the statistics of devfreq behavior
> + on a specific device. It shows the time spent in each state
> + and the number of transitions between states.
> In order to activate this ABI, the devfreq target device
> driver should provide the list of available frequencies
> - with its profile.
> + with its profile. If need to reset the statistics of devfreq
> + behavior on a specific device, enter 0(zero) to 'trans_stat'
> + as following:
> + echo 0 > /sys/class/devfreq/.../trans_stat
>
> What: /sys/class/devfreq/.../userspace/set_freq
> Date: September 2011
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index abecadeb3dc2..df31f430051d 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -1478,7 +1478,34 @@ static ssize_t trans_stat_show(struct device *dev,
> devfreq->total_trans);
> return len;
> }
> -static DEVICE_ATTR_RO(trans_stat);
> +
> +static ssize_t trans_stat_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct devfreq *df = to_devfreq(dev);
> + int err, value;
> +
> + if (df->profile->max_state == 0)
> + return count;
> +
> + err = kstrtoint(buf, 10, &value);
> + if (err || value != 0)
> + return -EINVAL;
> +
> + mutex_lock(&df->lock);
> + memset(df->time_in_state, 0, (df->profile->max_state *
> + sizeof(*df->time_in_state)));
> + memset(df->trans_table, 0, array3_size(sizeof(unsigned int),
> + df->profile->max_state,
> + df->profile->max_state));
> + df->total_trans = 0;
> + df->last_stat_updated = get_jiffies_64();
> + mutex_unlock(&df->lock);
> +
> + return count;
> +}
> +static DEVICE_ATTR_RW(trans_stat);
>
> static struct attribute *devfreq_attrs[] = {
> &dev_attr_name.attr,
>
Applied it. Thanks.
--
Best Regards,
Chanwoo Choi
Samsung Electronics
Hi,
Looks good. But, it include the some clean-up code
regardless of 'struct stats'. So, I modified them as following by myself:
- Remove the code touched the 'devfreq->profile' in this patch
- Use 'devfreq->stats.*' style instead of 'stats->*' in order to
keep the consistent coding style.
On 12/5/19 11:55 PM, Kamil Konieczny wrote:
> Count time and transitions between devfreq frequencies in separate struct
> for improved code readability and maintenance.
>
> Signed-off-by: Kamil Konieczny <[email protected]>
> Reviewed-by: Matthias Kaehlcke <[email protected]>
> ---
> Changes in v3:
> - removed freq_table and max_state from struct devfreq_stats as they are
> already present in struct devfreq_dev_profile
> - renamed last_stat_updated to last_update, as 'stat' is already present
> in struct devfreq_stats
> - define struct devfreq_stats stats; in devfreq as there is only one
> stats per devfreq
> - improve descriptions of devfreq_stats and stats
> - use profile instead of devfreq->profile in devfreq_add_device, as this
> var is already parameter
> - added Reviewed-by: Matthias Kaehlcke <[email protected]>
>
> Changes in v2:
> - squash three patches into one, do not modify devfreq_profile and separate stats
> into devfreq_stats
> ---
> drivers/devfreq/devfreq.c | 67 ++++++++++++++++++++-------------------
> include/linux/devfreq.h | 26 +++++++++------
> 2 files changed, 51 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 218eb64d7f28..bcd7e92d2cf3 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -198,6 +198,7 @@ static int set_freq_table(struct devfreq *devfreq)
> */
> int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> {
> + struct devfreq_stats *stats = &devfreq->stats;
> int lev, prev_lev, ret = 0;
> u64 cur_time;
>
> @@ -214,9 +215,7 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> goto out;
> }
>
> - devfreq->time_in_state[prev_lev] +=
> - cur_time - devfreq->last_stat_updated;
> -
> + stats->time_in_state[prev_lev] += cur_time - stats->last_update;
> lev = devfreq_get_freq_level(devfreq, freq);
> if (lev < 0) {
> ret = lev;
> @@ -224,13 +223,13 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> }
>
> if (lev != prev_lev) {
> - devfreq->trans_table[(prev_lev *
> - devfreq->profile->max_state) + lev]++;
> - devfreq->total_trans++;
> + stats->trans_table[(prev_lev * devfreq->profile->max_state) +
> + lev]++;
> + stats->total_trans++;
> }
>
> out:
> - devfreq->last_stat_updated = cur_time;
> + stats->last_update = cur_time;
> return ret;
> }
> EXPORT_SYMBOL(devfreq_update_status);
> @@ -525,7 +524,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
> msecs_to_jiffies(devfreq->profile->polling_ms));
>
> out_update:
> - devfreq->last_stat_updated = get_jiffies_64();
> + devfreq->stats.last_update = get_jiffies_64();
> devfreq->stop_polling = false;
>
> if (devfreq->profile->get_cur_freq &&
> @@ -735,28 +734,29 @@ struct devfreq *devfreq_add_device(struct device *dev,
> goto err_out;
> }
>
> - devfreq->trans_table = devm_kzalloc(&devfreq->dev,
> + devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev,
> array3_size(sizeof(unsigned int),
> - devfreq->profile->max_state,
> - devfreq->profile->max_state),
It is not good touching the 'devfreq->profile' variable
that is not related to 'struct devfreq_stats'. Just keep the previous code.
> + profile->max_state,
> + profile->max_state),
> GFP_KERNEL);
> - if (!devfreq->trans_table) {
> + if (!devfreq->stats.trans_table) {
> mutex_unlock(&devfreq->lock);
> err = -ENOMEM;
> goto err_devfreq;
> }
>
> - devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
> - devfreq->profile->max_state,
> - sizeof(*devfreq->time_in_state),
> + devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev,
> + profile->max_state,
ditto. Just keep the previous code.
> + sizeof(*devfreq->stats.time_in_state),
> GFP_KERNEL);
> - if (!devfreq->time_in_state) {
> + if (!devfreq->stats.time_in_state) {
> mutex_unlock(&devfreq->lock);
> err = -ENOMEM;
> goto err_devfreq;
> }
>
> - devfreq->last_stat_updated = get_jiffies_64();
> + devfreq->stats.last_update = get_jiffies_64();
> + devfreq->stats.total_trans = 0;
>
> srcu_init_notifier_head(&devfreq->transition_notifier_list);
>
> @@ -1435,9 +1435,11 @@ static ssize_t trans_stat_show(struct device *dev,
> struct device_attribute *attr, char *buf)
> {
> struct devfreq *devfreq = to_devfreq(dev);
> + struct devfreq_stats *stats = &devfreq->stats;
> + unsigned int max_state = devfreq->profile->max_state;
> + unsigned long *freq_table = devfreq->profile->freq_table;
> ssize_t len;
> int i, j;
> - unsigned int max_state = devfreq->profile->max_state;
It is not good touching the 'devfreq->profile' variable
that is not related to 'struct devfreq_stats'.
>
> if (max_state == 0)
> return sprintf(buf, "Not Supported.\n");
> @@ -1453,29 +1455,27 @@ static ssize_t trans_stat_show(struct device *dev,
> len = sprintf(buf, " From : To\n");
> len += sprintf(buf + len, " :");
> for (i = 0; i < max_state; i++)
> - len += sprintf(buf + len, "%10lu",
> - devfreq->profile->freq_table[i]);
> + len += sprintf(buf + len, "%10lu", freq_table[i]);
It is not good touching the 'devfreq->profile' variable
that is not related to 'struct devfreq_stats'.
>
> len += sprintf(buf + len, " time(ms)\n");
>
> for (i = 0; i < max_state; i++) {
> - if (devfreq->profile->freq_table[i]
> - == devfreq->previous_freq) {
> + if (freq_table[i] == devfreq->previous_freq)
ditto.
> len += sprintf(buf + len, "*");
> - } else {
Don't touch the something if it is not related to 'struct devfreq_stats'
> + else
> len += sprintf(buf + len, " ");
> - }
ditto.
> - len += sprintf(buf + len, "%10lu:",
> - devfreq->profile->freq_table[i]);
> +
> + len += sprintf(buf + len, "%10lu:", freq_table[i]);
ditto.
> for (j = 0; j < max_state; j++)
> len += sprintf(buf + len, "%10u",
> - devfreq->trans_table[(i * max_state) + j]);
> + stats->trans_table[(i * max_state) + j]);
> +
> len += sprintf(buf + len, "%10llu\n", (u64)
> - jiffies64_to_msecs(devfreq->time_in_state[i]));
> + jiffies64_to_msecs(stats->time_in_state[i]));
> }
>
> len += sprintf(buf + len, "Total transition : %u\n",
> - devfreq->total_trans);
> + stats->total_trans);
> return len;
> }
>
> @@ -1484,6 +1484,7 @@ static ssize_t trans_stat_store(struct device *dev,
> const char *buf, size_t count)
> {
> struct devfreq *df = to_devfreq(dev);
> + struct devfreq_stats *stats = &df->stats;
> unsigned int cnt = df->profile->max_state;
> int err, value;
>
> @@ -1495,10 +1496,10 @@ static ssize_t trans_stat_store(struct device *dev,
> return count;
>
> mutex_lock(&df->lock);
> - memset(df->time_in_state, 0, cnt * sizeof(u64));
> - memset(df->trans_table, 0, cnt * cnt * sizeof(int));
> - df->last_stat_updated = get_jiffies_64();
> - df->total_trans = 0;
> + memset(stats->time_in_state, 0, cnt * sizeof(u64));
> + memset(stats->trans_table, 0, cnt * cnt * sizeof(int));
> + stats->last_update = get_jiffies_64();
> + stats->total_trans = 0;
> mutex_unlock(&df->lock);
>
> return count;
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index 41f15e7a22b8..de2fdc56aa5b 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -106,6 +106,20 @@ struct devfreq_dev_profile {
> unsigned int max_state;
> };
>
> +/**
> + * struct devfreq_stats - Statistics of devfreq device behavior
> + * @total_trans: Number of devfreq transitions.
> + * @trans_table: Statistics of devfreq transitions.
> + * @time_in_state: Statistics of devfreq states.
> + * @last_update: The last time stats were updated.
> + */
> +struct devfreq_stats {
> + unsigned int total_trans;
> + unsigned int *trans_table;
> + u64 *time_in_state;
> + u64 last_update;
> +};
> +
> /**
> * struct devfreq - Device devfreq structure
> * @node: list node - contains the devices with devfreq that have been
> @@ -131,10 +145,7 @@ struct devfreq_dev_profile {
> * @suspend_freq: frequency of a device set during suspend phase.
> * @resume_freq: frequency of a device set in resume phase.
> * @suspend_count: suspend requests counter for a device.
> - * @total_trans: Number of devfreq transitions
> - * @trans_table: Statistics of devfreq transitions
> - * @time_in_state: Statistics of devfreq states
> - * @last_stat_updated: The last time stat updated
> + * @stats: Statistics of devfreq device behavior
> * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
> *
> * This structure stores the devfreq information for a give device.
> @@ -171,11 +182,8 @@ struct devfreq {
> unsigned long resume_freq;
> atomic_t suspend_count;
>
> - /* information for device frequency transition */
> - unsigned int total_trans;
> - unsigned int *trans_table;
> - u64 *time_in_state;
> - u64 last_stat_updated;
> + /* information for device frequency transitions */
> + struct devfreq_stats stats;
>
> struct srcu_notifier_head transition_notifier_list;
> };
>
--
Best Regards,
Chanwoo Choi
Samsung Electronics
From: Kamil Konieczny <[email protected]>
Count time and transitions between devfreq frequencies in separate
struct devfreq_stats for improved code readability and maintenance.
Signed-off-by: Kamil Konieczny <[email protected]>
Reviewed-by: Matthias Kaehlcke <[email protected]>
[cw00.choi: Fix the merge conflict in trasn_stat_store]
Signed-off-by: Chanwoo Choi <[email protected]>
---
drivers/devfreq/devfreq.c | 44 ++++++++++++++++++++-------------------
include/linux/devfreq.h | 26 +++++++++++++++--------
2 files changed, 40 insertions(+), 30 deletions(-)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index df31f430051d..1786a86b1779 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -214,8 +214,8 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
goto out;
}
- devfreq->time_in_state[prev_lev] +=
- cur_time - devfreq->last_stat_updated;
+ devfreq->stats.time_in_state[prev_lev] +=
+ cur_time - devfreq->stats.last_update;
lev = devfreq_get_freq_level(devfreq, freq);
if (lev < 0) {
@@ -224,13 +224,13 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
}
if (lev != prev_lev) {
- devfreq->trans_table[(prev_lev *
- devfreq->profile->max_state) + lev]++;
- devfreq->total_trans++;
+ devfreq->stats.trans_table[
+ (prev_lev * devfreq->profile->max_state) + lev]++;
+ devfreq->stats.total_trans++;
}
out:
- devfreq->last_stat_updated = cur_time;
+ devfreq->stats.last_update = cur_time;
return ret;
}
EXPORT_SYMBOL(devfreq_update_status);
@@ -525,7 +525,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
msecs_to_jiffies(devfreq->profile->polling_ms));
out_update:
- devfreq->last_stat_updated = get_jiffies_64();
+ devfreq->stats.last_update = get_jiffies_64();
devfreq->stop_polling = false;
if (devfreq->profile->get_cur_freq &&
@@ -735,28 +735,29 @@ struct devfreq *devfreq_add_device(struct device *dev,
goto err_out;
}
- devfreq->trans_table = devm_kzalloc(&devfreq->dev,
+ devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev,
array3_size(sizeof(unsigned int),
devfreq->profile->max_state,
devfreq->profile->max_state),
GFP_KERNEL);
- if (!devfreq->trans_table) {
+ if (!devfreq->stats.trans_table) {
mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_devfreq;
}
- devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
+ devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev,
devfreq->profile->max_state,
- sizeof(*devfreq->time_in_state),
+ sizeof(*devfreq->stats.time_in_state),
GFP_KERNEL);
- if (!devfreq->time_in_state) {
+ if (!devfreq->stats.time_in_state) {
mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_devfreq;
}
- devfreq->last_stat_updated = get_jiffies_64();
+ devfreq->stats.total_trans = 0;
+ devfreq->stats.last_update = get_jiffies_64();
srcu_init_notifier_head(&devfreq->transition_notifier_list);
@@ -1469,13 +1470,14 @@ static ssize_t trans_stat_show(struct device *dev,
devfreq->profile->freq_table[i]);
for (j = 0; j < max_state; j++)
len += sprintf(buf + len, "%10u",
- devfreq->trans_table[(i * max_state) + j]);
+ devfreq->stats.trans_table[(i * max_state) + j]);
+
len += sprintf(buf + len, "%10llu\n", (u64)
- jiffies64_to_msecs(devfreq->time_in_state[i]));
+ jiffies64_to_msecs(devfreq->stats.time_in_state[i]));
}
len += sprintf(buf + len, "Total transition : %u\n",
- devfreq->total_trans);
+ devfreq->stats.total_trans);
return len;
}
@@ -1494,13 +1496,13 @@ static ssize_t trans_stat_store(struct device *dev,
return -EINVAL;
mutex_lock(&df->lock);
- memset(df->time_in_state, 0, (df->profile->max_state *
- sizeof(*df->time_in_state)));
- memset(df->trans_table, 0, array3_size(sizeof(unsigned int),
+ memset(df->stats.time_in_state, 0, (df->profile->max_state *
+ sizeof(*df->stats.time_in_state)));
+ memset(df->stats.trans_table, 0, array3_size(sizeof(unsigned int),
df->profile->max_state,
df->profile->max_state));
- df->total_trans = 0;
- df->last_stat_updated = get_jiffies_64();
+ df->stats.total_trans = 0;
+ df->stats.last_update = get_jiffies_64();
mutex_unlock(&df->lock);
return count;
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 41f15e7a22b8..de2fdc56aa5b 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -106,6 +106,20 @@ struct devfreq_dev_profile {
unsigned int max_state;
};
+/**
+ * struct devfreq_stats - Statistics of devfreq device behavior
+ * @total_trans: Number of devfreq transitions.
+ * @trans_table: Statistics of devfreq transitions.
+ * @time_in_state: Statistics of devfreq states.
+ * @last_update: The last time stats were updated.
+ */
+struct devfreq_stats {
+ unsigned int total_trans;
+ unsigned int *trans_table;
+ u64 *time_in_state;
+ u64 last_update;
+};
+
/**
* struct devfreq - Device devfreq structure
* @node: list node - contains the devices with devfreq that have been
@@ -131,10 +145,7 @@ struct devfreq_dev_profile {
* @suspend_freq: frequency of a device set during suspend phase.
* @resume_freq: frequency of a device set in resume phase.
* @suspend_count: suspend requests counter for a device.
- * @total_trans: Number of devfreq transitions
- * @trans_table: Statistics of devfreq transitions
- * @time_in_state: Statistics of devfreq states
- * @last_stat_updated: The last time stat updated
+ * @stats: Statistics of devfreq device behavior
* @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
*
* This structure stores the devfreq information for a give device.
@@ -171,11 +182,8 @@ struct devfreq {
unsigned long resume_freq;
atomic_t suspend_count;
- /* information for device frequency transition */
- unsigned int total_trans;
- unsigned int *trans_table;
- u64 *time_in_state;
- u64 last_stat_updated;
+ /* information for device frequency transitions */
+ struct devfreq_stats stats;
struct srcu_notifier_head transition_notifier_list;
};
--
2.17.1
On 12/6/19 2:33 PM, Chanwoo Choi wrote:
> From: Kamil Konieczny <[email protected]>
>
> Count time and transitions between devfreq frequencies in separate
> struct devfreq_stats for improved code readability and maintenance.
>
> Signed-off-by: Kamil Konieczny <[email protected]>
> Reviewed-by: Matthias Kaehlcke <[email protected]>
> [cw00.choi: Fix the merge conflict in trasn_stat_store]
> Signed-off-by: Chanwoo Choi <[email protected]>
> ---
> drivers/devfreq/devfreq.c | 44 ++++++++++++++++++++-------------------
> include/linux/devfreq.h | 26 +++++++++++++++--------
> 2 files changed, 40 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index df31f430051d..1786a86b1779 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -214,8 +214,8 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> goto out;
> }
>
> - devfreq->time_in_state[prev_lev] +=
> - cur_time - devfreq->last_stat_updated;
> + devfreq->stats.time_in_state[prev_lev] +=
> + cur_time - devfreq->stats.last_update;
>
> lev = devfreq_get_freq_level(devfreq, freq);
> if (lev < 0) {
> @@ -224,13 +224,13 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> }
>
> if (lev != prev_lev) {
> - devfreq->trans_table[(prev_lev *
> - devfreq->profile->max_state) + lev]++;
> - devfreq->total_trans++;
> + devfreq->stats.trans_table[
> + (prev_lev * devfreq->profile->max_state) + lev]++;
> + devfreq->stats.total_trans++;
> }
>
> out:
> - devfreq->last_stat_updated = cur_time;
> + devfreq->stats.last_update = cur_time;
> return ret;
> }
> EXPORT_SYMBOL(devfreq_update_status);
> @@ -525,7 +525,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
> msecs_to_jiffies(devfreq->profile->polling_ms));
>
> out_update:
> - devfreq->last_stat_updated = get_jiffies_64();
> + devfreq->stats.last_update = get_jiffies_64();
> devfreq->stop_polling = false;
>
> if (devfreq->profile->get_cur_freq &&
> @@ -735,28 +735,29 @@ struct devfreq *devfreq_add_device(struct device *dev,
> goto err_out;
> }
>
> - devfreq->trans_table = devm_kzalloc(&devfreq->dev,
> + devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev,
> array3_size(sizeof(unsigned int),
> devfreq->profile->max_state,
> devfreq->profile->max_state),
> GFP_KERNEL);
> - if (!devfreq->trans_table) {
> + if (!devfreq->stats.trans_table) {
> mutex_unlock(&devfreq->lock);
> err = -ENOMEM;
> goto err_devfreq;
> }
>
> - devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
> + devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev,
> devfreq->profile->max_state,
> - sizeof(*devfreq->time_in_state),
> + sizeof(*devfreq->stats.time_in_state),
> GFP_KERNEL);
> - if (!devfreq->time_in_state) {
> + if (!devfreq->stats.time_in_state) {
> mutex_unlock(&devfreq->lock);
> err = -ENOMEM;
> goto err_devfreq;
> }
>
> - devfreq->last_stat_updated = get_jiffies_64();
> + devfreq->stats.total_trans = 0;
> + devfreq->stats.last_update = get_jiffies_64();
>
> srcu_init_notifier_head(&devfreq->transition_notifier_list);
>
> @@ -1469,13 +1470,14 @@ static ssize_t trans_stat_show(struct device *dev,
> devfreq->profile->freq_table[i]);
> for (j = 0; j < max_state; j++)
> len += sprintf(buf + len, "%10u",
> - devfreq->trans_table[(i * max_state) + j]);
> + devfreq->stats.trans_table[(i * max_state) + j]);
> +
> len += sprintf(buf + len, "%10llu\n", (u64)
> - jiffies64_to_msecs(devfreq->time_in_state[i]));
> + jiffies64_to_msecs(devfreq->stats.time_in_state[i]));
> }
>
> len += sprintf(buf + len, "Total transition : %u\n",
> - devfreq->total_trans);
> + devfreq->stats.total_trans);
> return len;
> }
>
> @@ -1494,13 +1496,13 @@ static ssize_t trans_stat_store(struct device *dev,
> return -EINVAL;
>
> mutex_lock(&df->lock);
> - memset(df->time_in_state, 0, (df->profile->max_state *
> - sizeof(*df->time_in_state)));
> - memset(df->trans_table, 0, array3_size(sizeof(unsigned int),
> + memset(df->stats.time_in_state, 0, (df->profile->max_state *
> + sizeof(*df->stats.time_in_state)));
> + memset(df->stats.trans_table, 0, array3_size(sizeof(unsigned int),
> df->profile->max_state,
> df->profile->max_state));
> - df->total_trans = 0;
> - df->last_stat_updated = get_jiffies_64();
> + df->stats.total_trans = 0;
> + df->stats.last_update = get_jiffies_64();
> mutex_unlock(&df->lock);
>
> return count;
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index 41f15e7a22b8..de2fdc56aa5b 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -106,6 +106,20 @@ struct devfreq_dev_profile {
> unsigned int max_state;
> };
>
> +/**
> + * struct devfreq_stats - Statistics of devfreq device behavior
> + * @total_trans: Number of devfreq transitions.
> + * @trans_table: Statistics of devfreq transitions.
> + * @time_in_state: Statistics of devfreq states.
> + * @last_update: The last time stats were updated.
> + */
> +struct devfreq_stats {
> + unsigned int total_trans;
> + unsigned int *trans_table;
> + u64 *time_in_state;
> + u64 last_update;
> +};
> +
> /**
> * struct devfreq - Device devfreq structure
> * @node: list node - contains the devices with devfreq that have been
> @@ -131,10 +145,7 @@ struct devfreq_dev_profile {
> * @suspend_freq: frequency of a device set during suspend phase.
> * @resume_freq: frequency of a device set in resume phase.
> * @suspend_count: suspend requests counter for a device.
> - * @total_trans: Number of devfreq transitions
> - * @trans_table: Statistics of devfreq transitions
> - * @time_in_state: Statistics of devfreq states
> - * @last_stat_updated: The last time stat updated
> + * @stats: Statistics of devfreq device behavior
> * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
> *
> * This structure stores the devfreq information for a give device.
> @@ -171,11 +182,8 @@ struct devfreq {
> unsigned long resume_freq;
> atomic_t suspend_count;
>
> - /* information for device frequency transition */
> - unsigned int total_trans;
> - unsigned int *trans_table;
> - u64 *time_in_state;
> - u64 last_stat_updated;
> + /* information for device frequency transitions */
> + struct devfreq_stats stats;
>
> struct srcu_notifier_head transition_notifier_list;
> };
>
Applied it. Thanks.
--
Best Regards,
Chanwoo Choi
Samsung Electronics