Count time and transitions between devfreq frequencies in separate struct
for improved code readability and maintenance.
Signed-off-by: Kamil Konieczny <[email protected]>
---
drivers/devfreq/devfreq.c | 156 ++++++++++++++++-------------
drivers/devfreq/exynos-bus.c | 6 +-
drivers/devfreq/governor_passive.c | 26 +++--
include/linux/devfreq.h | 43 ++++----
4 files changed, 129 insertions(+), 102 deletions(-)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index d79412b0de59..d85867a91230 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
*/
static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
{
+ struct devfreq_stats *stats = devfreq->profile->stats;
int lev;
- for (lev = 0; lev < devfreq->profile->max_state; lev++)
- if (freq == devfreq->profile->freq_table[lev])
+ for (lev = 0; lev < stats->max_state; lev++)
+ if (freq == stats->freq_table[lev])
return lev;
return -EINVAL;
@@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
static int set_freq_table(struct devfreq *devfreq)
{
struct devfreq_dev_profile *profile = devfreq->profile;
+ struct devfreq_stats *stats;
struct dev_pm_opp *opp;
unsigned long freq;
- int i, count;
+ int i, count, err = -ENOMEM;
/* Initialize the freq_table from OPP table */
count = dev_pm_opp_get_opp_count(devfreq->dev.parent);
if (count <= 0)
return -EINVAL;
- profile->max_state = count;
- profile->freq_table = devm_kcalloc(devfreq->dev.parent,
- count,
- sizeof(*profile->freq_table),
- GFP_KERNEL);
- if (!profile->freq_table) {
- profile->max_state = 0;
+ stats = devm_kzalloc(devfreq->dev.parent,
+ sizeof(struct devfreq_stats), GFP_KERNEL);
+ if (!stats)
return -ENOMEM;
- }
- for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
+ profile->stats = stats;
+ stats->max_state = count;
+ stats->freq_table = devm_kcalloc(devfreq->dev.parent,
+ count,
+ sizeof(*stats->freq_table),
+ GFP_KERNEL);
+ if (!stats->freq_table)
+ goto err_no_mem;
+
+ for (i = 0, freq = 0; i < count; i++, freq++) {
opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
if (IS_ERR(opp)) {
- devm_kfree(devfreq->dev.parent, profile->freq_table);
- profile->max_state = 0;
- return PTR_ERR(opp);
+ devm_kfree(devfreq->dev.parent, stats->freq_table);
+ stats->max_state = 0;
+ err = PTR_ERR(opp);
+ goto err_no_mem;
}
dev_pm_opp_put(opp);
- profile->freq_table[i] = freq;
+ stats->freq_table[i] = freq;
}
- profile->trans_table = devm_kzalloc(devfreq->dev.parent,
- array3_size(sizeof(unsigned int),
- count, count),
- GFP_KERNEL);
- if (!profile->trans_table)
+ stats->trans_table = devm_kzalloc(devfreq->dev.parent,
+ array3_size(sizeof(unsigned int),
+ count, count),
+ GFP_KERNEL);
+ if (!stats->trans_table)
goto err_no_mem;
- profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
- sizeof(*profile->time_in_state),
- GFP_KERNEL);
- if (!profile->time_in_state)
+ stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
+ sizeof(*stats->time_in_state),
+ GFP_KERNEL);
+ if (!stats->time_in_state)
goto err_no_mem;
- profile->last_time = get_jiffies_64();
- spin_lock_init(&profile->stats_lock);
+ stats->last_time = get_jiffies_64();
+ spin_lock_init(&stats->stats_lock);
return 0;
err_no_mem:
- profile->max_state = 0;
- return -ENOMEM;
+ stats->max_state = 0;
+ devm_kfree(devfreq->dev.parent, profile->stats);
+ profile->stats = NULL;
+ return err;
}
/**
@@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq)
*/
int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
{
- struct devfreq_dev_profile *profile = devfreq->profile;
+ struct devfreq_stats *stats = devfreq->profile->stats;
unsigned long long cur_time;
int lev, prev_lev, ret = 0;
@@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
/* Immediately exit if previous_freq is not initialized yet. */
if (!devfreq->previous_freq) {
- spin_lock(&profile->stats_lock);
- profile->last_time = cur_time;
- spin_unlock(&profile->stats_lock);
+ spin_lock(&stats->stats_lock);
+ stats->last_time = cur_time;
+ spin_unlock(&stats->stats_lock);
return 0;
}
prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq);
- spin_lock(&profile->stats_lock);
+ spin_lock(&stats->stats_lock);
if (prev_lev < 0) {
ret = prev_lev;
goto out;
}
- profile->time_in_state[prev_lev] +=
- cur_time - profile->last_time;
+ stats->time_in_state[prev_lev] += cur_time - stats->last_time;
lev = devfreq_get_freq_level(devfreq, freq);
if (lev < 0) {
ret = lev;
@@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
}
if (lev != prev_lev) {
- profile->trans_table[(prev_lev *
- profile->max_state) + lev]++;
- profile->total_trans++;
+ stats->trans_table[(prev_lev *
+ stats->max_state) + lev]++;
+ stats->total_trans++;
}
out:
- profile->last_time = cur_time;
- spin_unlock(&profile->stats_lock);
+ stats->last_time = cur_time;
+ spin_unlock(&stats->stats_lock);
return ret;
}
EXPORT_SYMBOL(devfreq_update_status);
@@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
queue_delayed_work(devfreq_wq, &devfreq->work,
msecs_to_jiffies(profile->polling_ms));
- spin_lock(&profile->stats_lock);
- profile->last_time = get_jiffies_64();
- spin_unlock(&profile->stats_lock);
+ spin_lock(&profile->stats->stats_lock);
+ profile->stats->last_time = get_jiffies_64();
+ spin_unlock(&profile->stats->stats_lock);
devfreq->stop_polling = false;
if (profile->get_cur_freq &&
@@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
devfreq->data = data;
devfreq->nb.notifier_call = devfreq_notifier_call;
- if (!profile->max_state && !profile->freq_table) {
+ if (!profile->stats) {
mutex_unlock(&devfreq->lock);
err = set_freq_table(devfreq);
if (err < 0)
@@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct devfreq *df = to_devfreq(dev);
+ struct devfreq_stats *stats = df->profile->stats;
unsigned long value;
int ret;
@@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
goto unlock;
}
} else {
- unsigned long *freq_table = df->profile->freq_table;
+ unsigned long *freq_table = stats->freq_table;
/* Get minimum frequency according to sorting order */
- if (freq_table[0] < freq_table[df->profile->max_state - 1])
+ if (freq_table[0] < freq_table[stats->max_state - 1])
value = freq_table[0];
else
- value = freq_table[df->profile->max_state - 1];
+ value = freq_table[stats->max_state - 1];
}
df->min_freq = value;
@@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct devfreq *df = to_devfreq(dev);
+ struct devfreq_stats *stats = df->profile->stats;
unsigned long value;
int ret;
@@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
goto unlock;
}
} else {
- unsigned long *freq_table = df->profile->freq_table;
+ unsigned long *freq_table = stats->freq_table;
/* Get maximum frequency according to sorting order */
- if (freq_table[0] < freq_table[df->profile->max_state - 1])
- value = freq_table[df->profile->max_state - 1];
+ if (freq_table[0] < freq_table[stats->max_state - 1])
+ value = freq_table[stats->max_state - 1];
else
value = freq_table[0];
}
@@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d,
char *buf)
{
struct devfreq *df = to_devfreq(d);
+ struct devfreq_stats *stats = df->profile->stats;
ssize_t count = 0;
int i;
mutex_lock(&df->lock);
- for (i = 0; i < df->profile->max_state; i++)
+ for (i = 0; i < stats->max_state; i++)
count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
- "%lu ", df->profile->freq_table[i]);
+ "%lu ", stats->freq_table[i]);
mutex_unlock(&df->lock);
/* Truncate the trailing space */
@@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev,
{
struct devfreq *devfreq = to_devfreq(dev);
struct devfreq_dev_profile *profile = devfreq->profile;
+ struct devfreq_stats *stats = profile->stats;
+ unsigned int max_state = stats->max_state;
ssize_t len;
int i, j;
- unsigned int max_state = profile->max_state;
if (!devfreq->stop_polling &&
devfreq_update_status(devfreq, devfreq->previous_freq))
@@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev,
len = sprintf(buf, " From : To\n");
len += sprintf(buf + len, " :");
- spin_lock(&profile->stats_lock);
+ spin_lock(&stats->stats_lock);
for (i = 0; i < max_state; i++)
len += sprintf(buf + len, "%10lu",
- profile->freq_table[i]);
+ stats->freq_table[i]);
len += sprintf(buf + len, " time(ms)\n");
for (i = 0; i < max_state; i++) {
- if (profile->freq_table[i] == devfreq->previous_freq)
+ if (stats->freq_table[i] == devfreq->previous_freq)
len += sprintf(buf + len, "*");
else
len += sprintf(buf + len, " ");
len += sprintf(buf + len, "%10lu:",
- profile->freq_table[i]);
+ stats->freq_table[i]);
for (j = 0; j < max_state; j++)
len += sprintf(buf + len, "%10u",
- profile->trans_table[(i * max_state) + j]);
+ stats->trans_table[(i * max_state) + j]);
len += sprintf(buf + len, "%10llu\n", (u64)
- jiffies64_to_msecs(profile->time_in_state[i]));
+ jiffies64_to_msecs(stats->time_in_state[i]));
}
len += sprintf(buf + len, "Total transition : %u\n",
- profile->total_trans);
- spin_unlock(&profile->stats_lock);
+ stats->total_trans);
+ spin_unlock(&stats->stats_lock);
return len;
}
static DEVICE_ATTR_RO(trans_stat);
-static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile)
+static void defvreq_stats_clear_table(struct devfreq_stats *stats)
{
- unsigned int count = profile->max_state;
-
- spin_lock(&profile->stats_lock);
- memset(profile->time_in_state, 0, count * sizeof(u64));
- memset(profile->trans_table, 0, count * count * sizeof(int));
- profile->last_time = get_jiffies_64();
- profile->total_trans = 0;
- spin_unlock(&profile->stats_lock);
+ unsigned int count = stats->max_state;
+
+ spin_lock(&stats->stats_lock);
+ memset(stats->time_in_state, 0, count * sizeof(u64));
+ memset(stats->trans_table, 0, count * count * sizeof(int));
+ stats->last_time = get_jiffies_64();
+ stats->total_trans = 0;
+ spin_unlock(&stats->stats_lock);
}
static ssize_t trans_reset_store(struct device *dev,
@@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev,
{
struct devfreq *devfreq = to_devfreq(dev);
- defvreq_stats_clear_table(devfreq->profile);
+ defvreq_stats_clear_table(devfreq->profile->stats);
return count;
}
diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
index d9f377912c10..b212aae2bb3e 100644
--- a/drivers/devfreq/exynos-bus.c
+++ b/drivers/devfreq/exynos-bus.c
@@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
}
out:
- max_state = bus->devfreq->profile->max_state;
- min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
- max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
+ max_state = profile->stats->max_state;
+ min_freq = (profile->stats->freq_table[0] / 1000);
+ max_freq = (profile->stats->freq_table[max_state - 1] / 1000);
pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
dev_name(dev), min_freq, max_freq);
diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 58308948b863..b2d87a88335c 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
struct devfreq_passive_data *p_data
= (struct devfreq_passive_data *)devfreq->data;
struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
+ struct devfreq_stats *parent_stats = parent_devfreq->profile->stats;
+ struct devfreq_stats *stats;
unsigned long child_freq = ULONG_MAX;
struct dev_pm_opp *opp;
int i, count, ret = 0;
@@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
* device. And then the index is used for getting the suitable
* new frequency for passive devfreq device.
*/
- if (!devfreq->profile || !devfreq->profile->freq_table
- || devfreq->profile->max_state <= 0)
+ if (!devfreq->profile || !devfreq->profile->stats ||
+ devfreq->profile->stats->max_state <= 0 ||
+ !parent_devfreq->profile || !parent_devfreq->profile->stats ||
+ parent_devfreq->profile->stats->max_state <= 0)
return -EINVAL;
+ stats = devfreq->profile->stats;
+ parent_stats = parent_devfreq->profile->stats;
/*
* The passive governor have to get the correct frequency from OPP
* list of parent device. Because in this case, *freq is temporary
@@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
* Get the OPP table's index of decided freqeuncy by governor
* of parent device.
*/
- for (i = 0; i < parent_devfreq->profile->max_state; i++)
- if (parent_devfreq->profile->freq_table[i] == *freq)
+ for (i = 0; i < parent_stats->max_state; i++)
+ if (parent_stats->freq_table[i] == *freq)
break;
- if (i == parent_devfreq->profile->max_state) {
+ if (i == parent_stats->max_state) {
ret = -EINVAL;
goto out;
}
/* Get the suitable frequency by using index of parent device. */
- if (i < devfreq->profile->max_state) {
- child_freq = devfreq->profile->freq_table[i];
+ if (i < stats->max_state) {
+ child_freq = stats->freq_table[i];
} else {
- count = devfreq->profile->max_state;
- child_freq = devfreq->profile->freq_table[count - 1];
+ count = stats->max_state;
+ child_freq = stats->freq_table[count - 1];
}
/* Return the suitable frequency for passive device. */
@@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
if (ret < 0)
goto out;
- if (devfreq->profile->freq_table
+ if (devfreq->profile->stats
&& (devfreq_update_status(devfreq, freq)))
dev_err(&devfreq->dev,
"Couldn't update frequency transition information.\n");
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 4ceb2a517a9c..8459af1a1583 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -64,6 +64,30 @@ struct devfreq_dev_status {
*/
#define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
+/**
+ * struct devfreq_stats - Devfreq's transitions stats counters
+ * @freq_table: Optional list of frequencies to support statistics
+ * and freq_table must be generated in ascending order.
+ * @max_state: The size of freq_table.
+ * @total_trans: Number of devfreq transitions
+ * @trans_table: Statistics of devfreq transitions
+ * @time_in_state: Statistics of devfreq states
+ * @last_time: The last time stats were updated
+ * @stats_lock: Lock protecting trans_table, time_in_state,
+ * last_time and total_trans used for statistics
+ */
+struct devfreq_stats {
+ unsigned long *freq_table;
+ unsigned int max_state;
+
+ /* information for device frequency transition */
+ unsigned int total_trans;
+ unsigned int *trans_table;
+ u64 *time_in_state;
+ unsigned long long last_time;
+ spinlock_t stats_lock;
+};
+
/**
* struct devfreq_dev_profile - Devfreq's user device profile
* @initial_freq: The operating frequency when devfreq_add_device() is
@@ -88,15 +112,7 @@ struct devfreq_dev_status {
* from devfreq_remove_device() call. If the user
* has registered devfreq->nb at a notifier-head,
* this is the time to unregister it.
- * @freq_table: Optional list of frequencies to support statistics
- * and freq_table must be generated in ascending order.
- * @max_state: The size of freq_table.
- * @total_trans: Number of devfreq transitions
- * @trans_table: Statistics of devfreq transitions
- * @time_in_state: Statistics of devfreq states
- * @last_time: The last time stats were updated
- * @stats_lock: Lock protecting trans_table, time_in_state,
- * last_time and total_trans used for statistics
+ * @stats: Statistics of devfreq states and state transitions
*/
struct devfreq_dev_profile {
unsigned long initial_freq;
@@ -108,14 +124,7 @@ struct devfreq_dev_profile {
int (*get_cur_freq)(struct device *dev, unsigned long *freq);
void (*exit)(struct device *dev);
- unsigned long *freq_table;
- unsigned int max_state;
- /* information for device frequency transition */
- unsigned int total_trans;
- unsigned int *trans_table;
- u64 *time_in_state;
- unsigned long long last_time;
- spinlock_t stats_lock;
+ struct devfreq_stats *stats;
};
/**
--
2.24.0
Hi Kamil,
The 'freq_table' and 'max_state' in the devfreq_dev_profile
were used in the ARM Mali device driver[1][2][3]. Although ARM Mali
device driver was posted to mainline kernel, they used
them for a long time. It means that this patch break
the compatibility. The ARM Mali drivers are very
important devfreq device driver.
[1] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/bifrost-kernel#
[2] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/midgard-kernel
[3] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/utgard-kernel
Also, the devfreq device driver specifies their own
information and data into devfreq_dev_profile structure
before registering the devfreq device with devfreq_add_device().
This patch breaks the basic usage rule of devfreq_dev_profile structure.
So, I can't agree this patch. Not ack.
Regards,
Chanwoo Choi
On 11/13/19 6:13 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]>
> ---
> drivers/devfreq/devfreq.c | 156 ++++++++++++++++-------------
> drivers/devfreq/exynos-bus.c | 6 +-
> drivers/devfreq/governor_passive.c | 26 +++--
> include/linux/devfreq.h | 43 ++++----
> 4 files changed, 129 insertions(+), 102 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index d79412b0de59..d85867a91230 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
> */
> static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
> {
> + struct devfreq_stats *stats = devfreq->profile->stats;
> int lev;
>
> - for (lev = 0; lev < devfreq->profile->max_state; lev++)
> - if (freq == devfreq->profile->freq_table[lev])
> + for (lev = 0; lev < stats->max_state; lev++)
> + if (freq == stats->freq_table[lev])
> return lev;
>
> return -EINVAL;
> @@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
> static int set_freq_table(struct devfreq *devfreq)
> {
> struct devfreq_dev_profile *profile = devfreq->profile;
> + struct devfreq_stats *stats;
> struct dev_pm_opp *opp;
> unsigned long freq;
> - int i, count;
> + int i, count, err = -ENOMEM;
>
> /* Initialize the freq_table from OPP table */
> count = dev_pm_opp_get_opp_count(devfreq->dev.parent);
> if (count <= 0)
> return -EINVAL;
>
> - profile->max_state = count;
> - profile->freq_table = devm_kcalloc(devfreq->dev.parent,
> - count,
> - sizeof(*profile->freq_table),
> - GFP_KERNEL);
> - if (!profile->freq_table) {
> - profile->max_state = 0;
> + stats = devm_kzalloc(devfreq->dev.parent,
> + sizeof(struct devfreq_stats), GFP_KERNEL);
> + if (!stats)
> return -ENOMEM;
> - }
>
> - for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
> + profile->stats = stats;
> + stats->max_state = count;
> + stats->freq_table = devm_kcalloc(devfreq->dev.parent,
> + count,
> + sizeof(*stats->freq_table),
> + GFP_KERNEL);
> + if (!stats->freq_table)
> + goto err_no_mem;
> +
> + for (i = 0, freq = 0; i < count; i++, freq++) {
> opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
> if (IS_ERR(opp)) {
> - devm_kfree(devfreq->dev.parent, profile->freq_table);
> - profile->max_state = 0;
> - return PTR_ERR(opp);
> + devm_kfree(devfreq->dev.parent, stats->freq_table);
> + stats->max_state = 0;
> + err = PTR_ERR(opp);
> + goto err_no_mem;
> }
> dev_pm_opp_put(opp);
> - profile->freq_table[i] = freq;
> + stats->freq_table[i] = freq;
> }
>
> - profile->trans_table = devm_kzalloc(devfreq->dev.parent,
> - array3_size(sizeof(unsigned int),
> - count, count),
> - GFP_KERNEL);
> - if (!profile->trans_table)
> + stats->trans_table = devm_kzalloc(devfreq->dev.parent,
> + array3_size(sizeof(unsigned int),
> + count, count),
> + GFP_KERNEL);
> + if (!stats->trans_table)
> goto err_no_mem;
>
> - profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
> - sizeof(*profile->time_in_state),
> - GFP_KERNEL);
> - if (!profile->time_in_state)
> + stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
> + sizeof(*stats->time_in_state),
> + GFP_KERNEL);
> + if (!stats->time_in_state)
> goto err_no_mem;
>
> - profile->last_time = get_jiffies_64();
> - spin_lock_init(&profile->stats_lock);
> + stats->last_time = get_jiffies_64();
> + spin_lock_init(&stats->stats_lock);
>
> return 0;
> err_no_mem:
> - profile->max_state = 0;
> - return -ENOMEM;
> + stats->max_state = 0;
> + devm_kfree(devfreq->dev.parent, profile->stats);
> + profile->stats = NULL;
> + return err;
> }
>
> /**
> @@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq)
> */
> int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> {
> - struct devfreq_dev_profile *profile = devfreq->profile;
> + struct devfreq_stats *stats = devfreq->profile->stats;
> unsigned long long cur_time;
> int lev, prev_lev, ret = 0;
>
> @@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>
> /* Immediately exit if previous_freq is not initialized yet. */
> if (!devfreq->previous_freq) {
> - spin_lock(&profile->stats_lock);
> - profile->last_time = cur_time;
> - spin_unlock(&profile->stats_lock);
> + spin_lock(&stats->stats_lock);
> + stats->last_time = cur_time;
> + spin_unlock(&stats->stats_lock);
> return 0;
> }
>
> prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq);
>
> - spin_lock(&profile->stats_lock);
> + spin_lock(&stats->stats_lock);
> if (prev_lev < 0) {
> ret = prev_lev;
> goto out;
> }
>
> - profile->time_in_state[prev_lev] +=
> - cur_time - profile->last_time;
> + stats->time_in_state[prev_lev] += cur_time - stats->last_time;
> lev = devfreq_get_freq_level(devfreq, freq);
> if (lev < 0) {
> ret = lev;
> @@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
> }
>
> if (lev != prev_lev) {
> - profile->trans_table[(prev_lev *
> - profile->max_state) + lev]++;
> - profile->total_trans++;
> + stats->trans_table[(prev_lev *
> + stats->max_state) + lev]++;
> + stats->total_trans++;
> }
>
> out:
> - profile->last_time = cur_time;
> - spin_unlock(&profile->stats_lock);
> + stats->last_time = cur_time;
> + spin_unlock(&stats->stats_lock);
> return ret;
> }
> EXPORT_SYMBOL(devfreq_update_status);
> @@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
> queue_delayed_work(devfreq_wq, &devfreq->work,
> msecs_to_jiffies(profile->polling_ms));
>
> - spin_lock(&profile->stats_lock);
> - profile->last_time = get_jiffies_64();
> - spin_unlock(&profile->stats_lock);
> + spin_lock(&profile->stats->stats_lock);
> + profile->stats->last_time = get_jiffies_64();
> + spin_unlock(&profile->stats->stats_lock);
> devfreq->stop_polling = false;
>
> if (profile->get_cur_freq &&
> @@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
> devfreq->data = data;
> devfreq->nb.notifier_call = devfreq_notifier_call;
>
> - if (!profile->max_state && !profile->freq_table) {
> + if (!profile->stats) {
> mutex_unlock(&devfreq->lock);
> err = set_freq_table(devfreq);
> if (err < 0)
> @@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
> const char *buf, size_t count)
> {
> struct devfreq *df = to_devfreq(dev);
> + struct devfreq_stats *stats = df->profile->stats;
> unsigned long value;
> int ret;
>
> @@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
> goto unlock;
> }
> } else {
> - unsigned long *freq_table = df->profile->freq_table;
> + unsigned long *freq_table = stats->freq_table;
>
> /* Get minimum frequency according to sorting order */
> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
> + if (freq_table[0] < freq_table[stats->max_state - 1])
> value = freq_table[0];
> else
> - value = freq_table[df->profile->max_state - 1];
> + value = freq_table[stats->max_state - 1];
> }
>
> df->min_freq = value;
> @@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
> const char *buf, size_t count)
> {
> struct devfreq *df = to_devfreq(dev);
> + struct devfreq_stats *stats = df->profile->stats;
> unsigned long value;
> int ret;
>
> @@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
> goto unlock;
> }
> } else {
> - unsigned long *freq_table = df->profile->freq_table;
> + unsigned long *freq_table = stats->freq_table;
>
> /* Get maximum frequency according to sorting order */
> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
> - value = freq_table[df->profile->max_state - 1];
> + if (freq_table[0] < freq_table[stats->max_state - 1])
> + value = freq_table[stats->max_state - 1];
> else
> value = freq_table[0];
> }
> @@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d,
> char *buf)
> {
> struct devfreq *df = to_devfreq(d);
> + struct devfreq_stats *stats = df->profile->stats;
> ssize_t count = 0;
> int i;
>
> mutex_lock(&df->lock);
>
> - for (i = 0; i < df->profile->max_state; i++)
> + for (i = 0; i < stats->max_state; i++)
> count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
> - "%lu ", df->profile->freq_table[i]);
> + "%lu ", stats->freq_table[i]);
>
> mutex_unlock(&df->lock);
> /* Truncate the trailing space */
> @@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev,
> {
> struct devfreq *devfreq = to_devfreq(dev);
> struct devfreq_dev_profile *profile = devfreq->profile;
> + struct devfreq_stats *stats = profile->stats;
> + unsigned int max_state = stats->max_state;
> ssize_t len;
> int i, j;
> - unsigned int max_state = profile->max_state;
>
> if (!devfreq->stop_polling &&
> devfreq_update_status(devfreq, devfreq->previous_freq))
> @@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev,
> len = sprintf(buf, " From : To\n");
> len += sprintf(buf + len, " :");
>
> - spin_lock(&profile->stats_lock);
> + spin_lock(&stats->stats_lock);
> for (i = 0; i < max_state; i++)
> len += sprintf(buf + len, "%10lu",
> - profile->freq_table[i]);
> + stats->freq_table[i]);
>
> len += sprintf(buf + len, " time(ms)\n");
>
> for (i = 0; i < max_state; i++) {
> - if (profile->freq_table[i] == devfreq->previous_freq)
> + if (stats->freq_table[i] == devfreq->previous_freq)
> len += sprintf(buf + len, "*");
> else
> len += sprintf(buf + len, " ");
>
> len += sprintf(buf + len, "%10lu:",
> - profile->freq_table[i]);
> + stats->freq_table[i]);
> for (j = 0; j < max_state; j++)
> len += sprintf(buf + len, "%10u",
> - profile->trans_table[(i * max_state) + j]);
> + stats->trans_table[(i * max_state) + j]);
> len += sprintf(buf + len, "%10llu\n", (u64)
> - jiffies64_to_msecs(profile->time_in_state[i]));
> + jiffies64_to_msecs(stats->time_in_state[i]));
> }
>
> len += sprintf(buf + len, "Total transition : %u\n",
> - profile->total_trans);
> - spin_unlock(&profile->stats_lock);
> + stats->total_trans);
> + spin_unlock(&stats->stats_lock);
> return len;
> }
> static DEVICE_ATTR_RO(trans_stat);
>
> -static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile)
> +static void defvreq_stats_clear_table(struct devfreq_stats *stats)
> {
> - unsigned int count = profile->max_state;
> -
> - spin_lock(&profile->stats_lock);
> - memset(profile->time_in_state, 0, count * sizeof(u64));
> - memset(profile->trans_table, 0, count * count * sizeof(int));
> - profile->last_time = get_jiffies_64();
> - profile->total_trans = 0;
> - spin_unlock(&profile->stats_lock);
> + unsigned int count = stats->max_state;
> +
> + spin_lock(&stats->stats_lock);
> + memset(stats->time_in_state, 0, count * sizeof(u64));
> + memset(stats->trans_table, 0, count * count * sizeof(int));
> + stats->last_time = get_jiffies_64();
> + stats->total_trans = 0;
> + spin_unlock(&stats->stats_lock);
> }
>
> static ssize_t trans_reset_store(struct device *dev,
> @@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev,
> {
> struct devfreq *devfreq = to_devfreq(dev);
>
> - defvreq_stats_clear_table(devfreq->profile);
> + defvreq_stats_clear_table(devfreq->profile->stats);
>
> return count;
> }
> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> index d9f377912c10..b212aae2bb3e 100644
> --- a/drivers/devfreq/exynos-bus.c
> +++ b/drivers/devfreq/exynos-bus.c
> @@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
> }
>
> out:
> - max_state = bus->devfreq->profile->max_state;
> - min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
> - max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
> + max_state = profile->stats->max_state;
> + min_freq = (profile->stats->freq_table[0] / 1000);
> + max_freq = (profile->stats->freq_table[max_state - 1] / 1000);
> pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
> dev_name(dev), min_freq, max_freq);
>
> diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
> index 58308948b863..b2d87a88335c 100644
> --- a/drivers/devfreq/governor_passive.c
> +++ b/drivers/devfreq/governor_passive.c
> @@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
> struct devfreq_passive_data *p_data
> = (struct devfreq_passive_data *)devfreq->data;
> struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
> + struct devfreq_stats *parent_stats = parent_devfreq->profile->stats;
> + struct devfreq_stats *stats;
> unsigned long child_freq = ULONG_MAX;
> struct dev_pm_opp *opp;
> int i, count, ret = 0;
> @@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
> * device. And then the index is used for getting the suitable
> * new frequency for passive devfreq device.
> */
> - if (!devfreq->profile || !devfreq->profile->freq_table
> - || devfreq->profile->max_state <= 0)
> + if (!devfreq->profile || !devfreq->profile->stats ||
> + devfreq->profile->stats->max_state <= 0 ||
> + !parent_devfreq->profile || !parent_devfreq->profile->stats ||
> + parent_devfreq->profile->stats->max_state <= 0)
> return -EINVAL;
>
> + stats = devfreq->profile->stats;
> + parent_stats = parent_devfreq->profile->stats;
> /*
> * The passive governor have to get the correct frequency from OPP
> * list of parent device. Because in this case, *freq is temporary
> @@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
> * Get the OPP table's index of decided freqeuncy by governor
> * of parent device.
> */
> - for (i = 0; i < parent_devfreq->profile->max_state; i++)
> - if (parent_devfreq->profile->freq_table[i] == *freq)
> + for (i = 0; i < parent_stats->max_state; i++)
> + if (parent_stats->freq_table[i] == *freq)
> break;
>
> - if (i == parent_devfreq->profile->max_state) {
> + if (i == parent_stats->max_state) {
> ret = -EINVAL;
> goto out;
> }
>
> /* Get the suitable frequency by using index of parent device. */
> - if (i < devfreq->profile->max_state) {
> - child_freq = devfreq->profile->freq_table[i];
> + if (i < stats->max_state) {
> + child_freq = stats->freq_table[i];
> } else {
> - count = devfreq->profile->max_state;
> - child_freq = devfreq->profile->freq_table[count - 1];
> + count = stats->max_state;
> + child_freq = stats->freq_table[count - 1];
> }
>
> /* Return the suitable frequency for passive device. */
> @@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
> if (ret < 0)
> goto out;
>
> - if (devfreq->profile->freq_table
> + if (devfreq->profile->stats
> && (devfreq_update_status(devfreq, freq)))
> dev_err(&devfreq->dev,
> "Couldn't update frequency transition information.\n");
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index 4ceb2a517a9c..8459af1a1583 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -64,6 +64,30 @@ struct devfreq_dev_status {
> */
> #define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
>
> +/**
> + * struct devfreq_stats - Devfreq's transitions stats counters
> + * @freq_table: Optional list of frequencies to support statistics
> + * and freq_table must be generated in ascending order.
> + * @max_state: The size of freq_table.
> + * @total_trans: Number of devfreq transitions
> + * @trans_table: Statistics of devfreq transitions
> + * @time_in_state: Statistics of devfreq states
> + * @last_time: The last time stats were updated
> + * @stats_lock: Lock protecting trans_table, time_in_state,
> + * last_time and total_trans used for statistics
> + */
> +struct devfreq_stats {
> + unsigned long *freq_table;
> + unsigned int max_state;
> +
> + /* information for device frequency transition */
> + unsigned int total_trans;
> + unsigned int *trans_table;
> + u64 *time_in_state;
> + unsigned long long last_time;
> + spinlock_t stats_lock;
> +};
> +
> /**
> * struct devfreq_dev_profile - Devfreq's user device profile
> * @initial_freq: The operating frequency when devfreq_add_device() is
> @@ -88,15 +112,7 @@ struct devfreq_dev_status {
> * from devfreq_remove_device() call. If the user
> * has registered devfreq->nb at a notifier-head,
> * this is the time to unregister it.
> - * @freq_table: Optional list of frequencies to support statistics
> - * and freq_table must be generated in ascending order.
> - * @max_state: The size of freq_table.
> - * @total_trans: Number of devfreq transitions
> - * @trans_table: Statistics of devfreq transitions
> - * @time_in_state: Statistics of devfreq states
> - * @last_time: The last time stats were updated
> - * @stats_lock: Lock protecting trans_table, time_in_state,
> - * last_time and total_trans used for statistics
> + * @stats: Statistics of devfreq states and state transitions
> */
> struct devfreq_dev_profile {
> unsigned long initial_freq;
> @@ -108,14 +124,7 @@ struct devfreq_dev_profile {
> int (*get_cur_freq)(struct device *dev, unsigned long *freq);
> void (*exit)(struct device *dev);
>
> - unsigned long *freq_table;
> - unsigned int max_state;
> - /* information for device frequency transition */
> - unsigned int total_trans;
> - unsigned int *trans_table;
> - u64 *time_in_state;
> - unsigned long long last_time;
> - spinlock_t stats_lock;
> + struct devfreq_stats *stats;
> };
>
> /**
>
Hi Chanwoo,
On 11/14/19 2:52 AM, Chanwoo Choi wrote:
> Hi Kamil,
>
> The 'freq_table' and 'max_state' in the devfreq_dev_profile
> were used in the ARM Mali device driver[1][2][3]. Although ARM Mali
> device driver was posted to mainline kernel, they used
> them for a long time. It means that this patch break
> the compatibility. The ARM Mali drivers are very
> important devfreq device driver.
This argument is not a a technical one and the official upstream
kernel policy is to not depend on out-of-tree drivers.
Besides the ARM Mali drivers are full of code like:
#if LINUX_VERSION_CODE >= KERNEL_VERSION(x, y, z)
...
#else
...
#endif
so few more instances of similar code won't do any harm.. ;-)
> [1] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/bifrost-kernel#
> [2] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/midgard-kernel
> [3] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/utgard-kernel
I took a look at ARM Mali drivers source code anyway and I fail to
see a rationale behind their behavior of doing 'freq_table' and
'max_state' initialization in the driver itself (instead of leaving
it up to the devfreq core code, like all in-kernel drivers are doing
already).
Could you please explain rationale behind ARM Mali drivers' special
needs?
[ Both ARM Mali and devfreq core code are using generic PM OPP code
these days to do 'freq_table' and 'max_state' initialization, the
only difference seems to be that ARM Mali creates the frequency
table in the descending order (but there also seems to be no real
need for it). ]
Maybe this is an opportunity to simplify also the ARM Mali driver?
> Also, the devfreq device driver specifies their own
> information and data into devfreq_dev_profile structure
> before registering the devfreq device with devfreq_add_device().
> This patch breaks the basic usage rule of devfreq_dev_profile structure.
Well, 'struct devfreq_stats *stats' can be trivially moved out of
'struct devfreq_profile' to 'struct devfreq' if you prefer it that
way..
Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics
> So, I can't agree this patch. Not ack.
>
> Regards,
> Chanwoo Choi
>
> On 11/13/19 6:13 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]>
>> ---
>> drivers/devfreq/devfreq.c | 156 ++++++++++++++++-------------
>> drivers/devfreq/exynos-bus.c | 6 +-
>> drivers/devfreq/governor_passive.c | 26 +++--
>> include/linux/devfreq.h | 43 ++++----
>> 4 files changed, 129 insertions(+), 102 deletions(-)
>>
>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>> index d79412b0de59..d85867a91230 100644
>> --- a/drivers/devfreq/devfreq.c
>> +++ b/drivers/devfreq/devfreq.c
>> @@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
>> */
>> static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>> {
>> + struct devfreq_stats *stats = devfreq->profile->stats;
>> int lev;
>>
>> - for (lev = 0; lev < devfreq->profile->max_state; lev++)
>> - if (freq == devfreq->profile->freq_table[lev])
>> + for (lev = 0; lev < stats->max_state; lev++)
>> + if (freq == stats->freq_table[lev])
>> return lev;
>>
>> return -EINVAL;
>> @@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>> static int set_freq_table(struct devfreq *devfreq)
>> {
>> struct devfreq_dev_profile *profile = devfreq->profile;
>> + struct devfreq_stats *stats;
>> struct dev_pm_opp *opp;
>> unsigned long freq;
>> - int i, count;
>> + int i, count, err = -ENOMEM;
>>
>> /* Initialize the freq_table from OPP table */
>> count = dev_pm_opp_get_opp_count(devfreq->dev.parent);
>> if (count <= 0)
>> return -EINVAL;
>>
>> - profile->max_state = count;
>> - profile->freq_table = devm_kcalloc(devfreq->dev.parent,
>> - count,
>> - sizeof(*profile->freq_table),
>> - GFP_KERNEL);
>> - if (!profile->freq_table) {
>> - profile->max_state = 0;
>> + stats = devm_kzalloc(devfreq->dev.parent,
>> + sizeof(struct devfreq_stats), GFP_KERNEL);
>> + if (!stats)
>> return -ENOMEM;
>> - }
>>
>> - for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
>> + profile->stats = stats;
>> + stats->max_state = count;
>> + stats->freq_table = devm_kcalloc(devfreq->dev.parent,
>> + count,
>> + sizeof(*stats->freq_table),
>> + GFP_KERNEL);
>> + if (!stats->freq_table)
>> + goto err_no_mem;
>> +
>> + for (i = 0, freq = 0; i < count; i++, freq++) {
>> opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
>> if (IS_ERR(opp)) {
>> - devm_kfree(devfreq->dev.parent, profile->freq_table);
>> - profile->max_state = 0;
>> - return PTR_ERR(opp);
>> + devm_kfree(devfreq->dev.parent, stats->freq_table);
>> + stats->max_state = 0;
>> + err = PTR_ERR(opp);
>> + goto err_no_mem;
>> }
>> dev_pm_opp_put(opp);
>> - profile->freq_table[i] = freq;
>> + stats->freq_table[i] = freq;
>> }
>>
>> - profile->trans_table = devm_kzalloc(devfreq->dev.parent,
>> - array3_size(sizeof(unsigned int),
>> - count, count),
>> - GFP_KERNEL);
>> - if (!profile->trans_table)
>> + stats->trans_table = devm_kzalloc(devfreq->dev.parent,
>> + array3_size(sizeof(unsigned int),
>> + count, count),
>> + GFP_KERNEL);
>> + if (!stats->trans_table)
>> goto err_no_mem;
>>
>> - profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>> - sizeof(*profile->time_in_state),
>> - GFP_KERNEL);
>> - if (!profile->time_in_state)
>> + stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>> + sizeof(*stats->time_in_state),
>> + GFP_KERNEL);
>> + if (!stats->time_in_state)
>> goto err_no_mem;
>>
>> - profile->last_time = get_jiffies_64();
>> - spin_lock_init(&profile->stats_lock);
>> + stats->last_time = get_jiffies_64();
>> + spin_lock_init(&stats->stats_lock);
>>
>> return 0;
>> err_no_mem:
>> - profile->max_state = 0;
>> - return -ENOMEM;
>> + stats->max_state = 0;
>> + devm_kfree(devfreq->dev.parent, profile->stats);
>> + profile->stats = NULL;
>> + return err;
>> }
>>
>> /**
>> @@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq)
>> */
>> int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>> {
>> - struct devfreq_dev_profile *profile = devfreq->profile;
>> + struct devfreq_stats *stats = devfreq->profile->stats;
>> unsigned long long cur_time;
>> int lev, prev_lev, ret = 0;
>>
>> @@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>
>> /* Immediately exit if previous_freq is not initialized yet. */
>> if (!devfreq->previous_freq) {
>> - spin_lock(&profile->stats_lock);
>> - profile->last_time = cur_time;
>> - spin_unlock(&profile->stats_lock);
>> + spin_lock(&stats->stats_lock);
>> + stats->last_time = cur_time;
>> + spin_unlock(&stats->stats_lock);
>> return 0;
>> }
>>
>> prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq);
>>
>> - spin_lock(&profile->stats_lock);
>> + spin_lock(&stats->stats_lock);
>> if (prev_lev < 0) {
>> ret = prev_lev;
>> goto out;
>> }
>>
>> - profile->time_in_state[prev_lev] +=
>> - cur_time - profile->last_time;
>> + stats->time_in_state[prev_lev] += cur_time - stats->last_time;
>> lev = devfreq_get_freq_level(devfreq, freq);
>> if (lev < 0) {
>> ret = lev;
>> @@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>> }
>>
>> if (lev != prev_lev) {
>> - profile->trans_table[(prev_lev *
>> - profile->max_state) + lev]++;
>> - profile->total_trans++;
>> + stats->trans_table[(prev_lev *
>> + stats->max_state) + lev]++;
>> + stats->total_trans++;
>> }
>>
>> out:
>> - profile->last_time = cur_time;
>> - spin_unlock(&profile->stats_lock);
>> + stats->last_time = cur_time;
>> + spin_unlock(&stats->stats_lock);
>> return ret;
>> }
>> EXPORT_SYMBOL(devfreq_update_status);
>> @@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
>> queue_delayed_work(devfreq_wq, &devfreq->work,
>> msecs_to_jiffies(profile->polling_ms));
>>
>> - spin_lock(&profile->stats_lock);
>> - profile->last_time = get_jiffies_64();
>> - spin_unlock(&profile->stats_lock);
>> + spin_lock(&profile->stats->stats_lock);
>> + profile->stats->last_time = get_jiffies_64();
>> + spin_unlock(&profile->stats->stats_lock);
>> devfreq->stop_polling = false;
>>
>> if (profile->get_cur_freq &&
>> @@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
>> devfreq->data = data;
>> devfreq->nb.notifier_call = devfreq_notifier_call;
>>
>> - if (!profile->max_state && !profile->freq_table) {
>> + if (!profile->stats) {
>> mutex_unlock(&devfreq->lock);
>> err = set_freq_table(devfreq);
>> if (err < 0)
>> @@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>> const char *buf, size_t count)
>> {
>> struct devfreq *df = to_devfreq(dev);
>> + struct devfreq_stats *stats = df->profile->stats;
>> unsigned long value;
>> int ret;
>>
>> @@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>> goto unlock;
>> }
>> } else {
>> - unsigned long *freq_table = df->profile->freq_table;
>> + unsigned long *freq_table = stats->freq_table;
>>
>> /* Get minimum frequency according to sorting order */
>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>> value = freq_table[0];
>> else
>> - value = freq_table[df->profile->max_state - 1];
>> + value = freq_table[stats->max_state - 1];
>> }
>>
>> df->min_freq = value;
>> @@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>> const char *buf, size_t count)
>> {
>> struct devfreq *df = to_devfreq(dev);
>> + struct devfreq_stats *stats = df->profile->stats;
>> unsigned long value;
>> int ret;
>>
>> @@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>> goto unlock;
>> }
>> } else {
>> - unsigned long *freq_table = df->profile->freq_table;
>> + unsigned long *freq_table = stats->freq_table;
>>
>> /* Get maximum frequency according to sorting order */
>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>> - value = freq_table[df->profile->max_state - 1];
>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>> + value = freq_table[stats->max_state - 1];
>> else
>> value = freq_table[0];
>> }
>> @@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d,
>> char *buf)
>> {
>> struct devfreq *df = to_devfreq(d);
>> + struct devfreq_stats *stats = df->profile->stats;
>> ssize_t count = 0;
>> int i;
>>
>> mutex_lock(&df->lock);
>>
>> - for (i = 0; i < df->profile->max_state; i++)
>> + for (i = 0; i < stats->max_state; i++)
>> count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
>> - "%lu ", df->profile->freq_table[i]);
>> + "%lu ", stats->freq_table[i]);
>>
>> mutex_unlock(&df->lock);
>> /* Truncate the trailing space */
>> @@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev,
>> {
>> struct devfreq *devfreq = to_devfreq(dev);
>> struct devfreq_dev_profile *profile = devfreq->profile;
>> + struct devfreq_stats *stats = profile->stats;
>> + unsigned int max_state = stats->max_state;
>> ssize_t len;
>> int i, j;
>> - unsigned int max_state = profile->max_state;
>>
>> if (!devfreq->stop_polling &&
>> devfreq_update_status(devfreq, devfreq->previous_freq))
>> @@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev,
>> len = sprintf(buf, " From : To\n");
>> len += sprintf(buf + len, " :");
>>
>> - spin_lock(&profile->stats_lock);
>> + spin_lock(&stats->stats_lock);
>> for (i = 0; i < max_state; i++)
>> len += sprintf(buf + len, "%10lu",
>> - profile->freq_table[i]);
>> + stats->freq_table[i]);
>>
>> len += sprintf(buf + len, " time(ms)\n");
>>
>> for (i = 0; i < max_state; i++) {
>> - if (profile->freq_table[i] == devfreq->previous_freq)
>> + if (stats->freq_table[i] == devfreq->previous_freq)
>> len += sprintf(buf + len, "*");
>> else
>> len += sprintf(buf + len, " ");
>>
>> len += sprintf(buf + len, "%10lu:",
>> - profile->freq_table[i]);
>> + stats->freq_table[i]);
>> for (j = 0; j < max_state; j++)
>> len += sprintf(buf + len, "%10u",
>> - profile->trans_table[(i * max_state) + j]);
>> + stats->trans_table[(i * max_state) + j]);
>> len += sprintf(buf + len, "%10llu\n", (u64)
>> - jiffies64_to_msecs(profile->time_in_state[i]));
>> + jiffies64_to_msecs(stats->time_in_state[i]));
>> }
>>
>> len += sprintf(buf + len, "Total transition : %u\n",
>> - profile->total_trans);
>> - spin_unlock(&profile->stats_lock);
>> + stats->total_trans);
>> + spin_unlock(&stats->stats_lock);
>> return len;
>> }
>> static DEVICE_ATTR_RO(trans_stat);
>>
>> -static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile)
>> +static void defvreq_stats_clear_table(struct devfreq_stats *stats)
>> {
>> - unsigned int count = profile->max_state;
>> -
>> - spin_lock(&profile->stats_lock);
>> - memset(profile->time_in_state, 0, count * sizeof(u64));
>> - memset(profile->trans_table, 0, count * count * sizeof(int));
>> - profile->last_time = get_jiffies_64();
>> - profile->total_trans = 0;
>> - spin_unlock(&profile->stats_lock);
>> + unsigned int count = stats->max_state;
>> +
>> + spin_lock(&stats->stats_lock);
>> + memset(stats->time_in_state, 0, count * sizeof(u64));
>> + memset(stats->trans_table, 0, count * count * sizeof(int));
>> + stats->last_time = get_jiffies_64();
>> + stats->total_trans = 0;
>> + spin_unlock(&stats->stats_lock);
>> }
>>
>> static ssize_t trans_reset_store(struct device *dev,
>> @@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev,
>> {
>> struct devfreq *devfreq = to_devfreq(dev);
>>
>> - defvreq_stats_clear_table(devfreq->profile);
>> + defvreq_stats_clear_table(devfreq->profile->stats);
>>
>> return count;
>> }
>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>> index d9f377912c10..b212aae2bb3e 100644
>> --- a/drivers/devfreq/exynos-bus.c
>> +++ b/drivers/devfreq/exynos-bus.c
>> @@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
>> }
>>
>> out:
>> - max_state = bus->devfreq->profile->max_state;
>> - min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
>> - max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
>> + max_state = profile->stats->max_state;
>> + min_freq = (profile->stats->freq_table[0] / 1000);
>> + max_freq = (profile->stats->freq_table[max_state - 1] / 1000);
>> pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
>> dev_name(dev), min_freq, max_freq);
>>
>> diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
>> index 58308948b863..b2d87a88335c 100644
>> --- a/drivers/devfreq/governor_passive.c
>> +++ b/drivers/devfreq/governor_passive.c
>> @@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>> struct devfreq_passive_data *p_data
>> = (struct devfreq_passive_data *)devfreq->data;
>> struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
>> + struct devfreq_stats *parent_stats = parent_devfreq->profile->stats;
>> + struct devfreq_stats *stats;
>> unsigned long child_freq = ULONG_MAX;
>> struct dev_pm_opp *opp;
>> int i, count, ret = 0;
>> @@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>> * device. And then the index is used for getting the suitable
>> * new frequency for passive devfreq device.
>> */
>> - if (!devfreq->profile || !devfreq->profile->freq_table
>> - || devfreq->profile->max_state <= 0)
>> + if (!devfreq->profile || !devfreq->profile->stats ||
>> + devfreq->profile->stats->max_state <= 0 ||
>> + !parent_devfreq->profile || !parent_devfreq->profile->stats ||
>> + parent_devfreq->profile->stats->max_state <= 0)
>> return -EINVAL;
>>
>> + stats = devfreq->profile->stats;
>> + parent_stats = parent_devfreq->profile->stats;
>> /*
>> * The passive governor have to get the correct frequency from OPP
>> * list of parent device. Because in this case, *freq is temporary
>> @@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>> * Get the OPP table's index of decided freqeuncy by governor
>> * of parent device.
>> */
>> - for (i = 0; i < parent_devfreq->profile->max_state; i++)
>> - if (parent_devfreq->profile->freq_table[i] == *freq)
>> + for (i = 0; i < parent_stats->max_state; i++)
>> + if (parent_stats->freq_table[i] == *freq)
>> break;
>>
>> - if (i == parent_devfreq->profile->max_state) {
>> + if (i == parent_stats->max_state) {
>> ret = -EINVAL;
>> goto out;
>> }
>>
>> /* Get the suitable frequency by using index of parent device. */
>> - if (i < devfreq->profile->max_state) {
>> - child_freq = devfreq->profile->freq_table[i];
>> + if (i < stats->max_state) {
>> + child_freq = stats->freq_table[i];
>> } else {
>> - count = devfreq->profile->max_state;
>> - child_freq = devfreq->profile->freq_table[count - 1];
>> + count = stats->max_state;
>> + child_freq = stats->freq_table[count - 1];
>> }
>>
>> /* Return the suitable frequency for passive device. */
>> @@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
>> if (ret < 0)
>> goto out;
>>
>> - if (devfreq->profile->freq_table
>> + if (devfreq->profile->stats
>> && (devfreq_update_status(devfreq, freq)))
>> dev_err(&devfreq->dev,
>> "Couldn't update frequency transition information.\n");
>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>> index 4ceb2a517a9c..8459af1a1583 100644
>> --- a/include/linux/devfreq.h
>> +++ b/include/linux/devfreq.h
>> @@ -64,6 +64,30 @@ struct devfreq_dev_status {
>> */
>> #define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
>>
>> +/**
>> + * struct devfreq_stats - Devfreq's transitions stats counters
>> + * @freq_table: Optional list of frequencies to support statistics
>> + * and freq_table must be generated in ascending order.
>> + * @max_state: The size of freq_table.
>> + * @total_trans: Number of devfreq transitions
>> + * @trans_table: Statistics of devfreq transitions
>> + * @time_in_state: Statistics of devfreq states
>> + * @last_time: The last time stats were updated
>> + * @stats_lock: Lock protecting trans_table, time_in_state,
>> + * last_time and total_trans used for statistics
>> + */
>> +struct devfreq_stats {
>> + unsigned long *freq_table;
>> + unsigned int max_state;
>> +
>> + /* information for device frequency transition */
>> + unsigned int total_trans;
>> + unsigned int *trans_table;
>> + u64 *time_in_state;
>> + unsigned long long last_time;
>> + spinlock_t stats_lock;
>> +};
>> +
>> /**
>> * struct devfreq_dev_profile - Devfreq's user device profile
>> * @initial_freq: The operating frequency when devfreq_add_device() is
>> @@ -88,15 +112,7 @@ struct devfreq_dev_status {
>> * from devfreq_remove_device() call. If the user
>> * has registered devfreq->nb at a notifier-head,
>> * this is the time to unregister it.
>> - * @freq_table: Optional list of frequencies to support statistics
>> - * and freq_table must be generated in ascending order.
>> - * @max_state: The size of freq_table.
>> - * @total_trans: Number of devfreq transitions
>> - * @trans_table: Statistics of devfreq transitions
>> - * @time_in_state: Statistics of devfreq states
>> - * @last_time: The last time stats were updated
>> - * @stats_lock: Lock protecting trans_table, time_in_state,
>> - * last_time and total_trans used for statistics
>> + * @stats: Statistics of devfreq states and state transitions
>> */
>> struct devfreq_dev_profile {
>> unsigned long initial_freq;
>> @@ -108,14 +124,7 @@ struct devfreq_dev_profile {
>> int (*get_cur_freq)(struct device *dev, unsigned long *freq);
>> void (*exit)(struct device *dev);
>>
>> - unsigned long *freq_table;
>> - unsigned int max_state;
>> - /* information for device frequency transition */
>> - unsigned int total_trans;
>> - unsigned int *trans_table;
>> - u64 *time_in_state;
>> - unsigned long long last_time;
>> - spinlock_t stats_lock;
>> + struct devfreq_stats *stats;
>> };
>>
>> /**
>>
Hi Bartlomiej,
On 11/15/19 3:01 AM, Bartlomiej Zolnierkiewicz wrote:
>
> Hi Chanwoo,
>
> On 11/14/19 2:52 AM, Chanwoo Choi wrote:
>> Hi Kamil,
>>
>> The 'freq_table' and 'max_state' in the devfreq_dev_profile
>> were used in the ARM Mali device driver[1][2][3]. Although ARM Mali
>> device driver was posted to mainline kernel, they used
>> them for a long time. It means that this patch break
>> the compatibility. The ARM Mali drivers are very
>> important devfreq device driver.
>
> This argument is not a a technical one and the official upstream
> kernel policy is to not depend on out-of-tree drivers.
>
> Besides the ARM Mali drivers are full of code like:
>
> #if LINUX_VERSION_CODE >= KERNEL_VERSION(x, y, z)
> ...
> #else
> ...
> #endif
>
> so few more instances of similar code won't do any harm.. ;-)
>
>> [1] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/bifrost-kernel#
>> [2] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/midgard-kernel
>> [3] https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/utgard-kernel
>
> I took a look at ARM Mali drivers source code anyway and I fail to
> see a rationale behind their behavior of doing 'freq_table' and
> 'max_state' initialization in the driver itself (instead of leaving
> it up to the devfreq core code, like all in-kernel drivers are doing
> already).
>
> Could you please explain rationale behind ARM Mali drivers' special
> needs?
>
> [ Both ARM Mali and devfreq core code are using generic PM OPP code
> these days to do 'freq_table' and 'max_state' initialization, the
> only difference seems to be that ARM Mali creates the frequency
> table in the descending order (but there also seems to be no real
> need for it). ]
>
> Maybe this is an opportunity to simplify also the ARM Mali driver?
OK. I agree to simplify them on this time.
For touching the 'freq_table' and 'max_state', need to fix
the descending order of freq_table.
The partition_enable_ops() in the drivers/thermal/devfreq_cooling.c
requires the descending order of freq_table. Have to change it by using
the ascending time or support both ascending and descending order for freq_table.
1. Move freq_table, max_state of devfreq_dev_profile to struct devfreq
2. Edit partition_enable_ops() in the drivers/thermal/devfreq_cooling.c
by using ascending order instead of descending order.
>
>> Also, the devfreq device driver specifies their own
>> information and data into devfreq_dev_profile structure
>> before registering the devfreq device with devfreq_add_device().
>> This patch breaks the basic usage rule of devfreq_dev_profile structure.
>
> Well, 'struct devfreq_stats *stats' can be trivially moved out of
> 'struct devfreq_profile' to 'struct devfreq' if you prefer it that
> way..
>
> Best regards,
> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics
>
>> So, I can't agree this patch. Not ack.
>>
>> Regards,
>> Chanwoo Choi
>>
>> On 11/13/19 6:13 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]>
>>> ---
>>> drivers/devfreq/devfreq.c | 156 ++++++++++++++++-------------
>>> drivers/devfreq/exynos-bus.c | 6 +-
>>> drivers/devfreq/governor_passive.c | 26 +++--
>>> include/linux/devfreq.h | 43 ++++----
>>> 4 files changed, 129 insertions(+), 102 deletions(-)
>>>
>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>>> index d79412b0de59..d85867a91230 100644
>>> --- a/drivers/devfreq/devfreq.c
>>> +++ b/drivers/devfreq/devfreq.c
>>> @@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
>>> */
>>> static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>>> {
>>> + struct devfreq_stats *stats = devfreq->profile->stats;
>>> int lev;
>>>
>>> - for (lev = 0; lev < devfreq->profile->max_state; lev++)
>>> - if (freq == devfreq->profile->freq_table[lev])
>>> + for (lev = 0; lev < stats->max_state; lev++)
>>> + if (freq == stats->freq_table[lev])
>>> return lev;
>>>
>>> return -EINVAL;
>>> @@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>>> static int set_freq_table(struct devfreq *devfreq)
>>> {
>>> struct devfreq_dev_profile *profile = devfreq->profile;
>>> + struct devfreq_stats *stats;
>>> struct dev_pm_opp *opp;
>>> unsigned long freq;
>>> - int i, count;
>>> + int i, count, err = -ENOMEM;
>>>
>>> /* Initialize the freq_table from OPP table */
>>> count = dev_pm_opp_get_opp_count(devfreq->dev.parent);
>>> if (count <= 0)
>>> return -EINVAL;
>>>
>>> - profile->max_state = count;
>>> - profile->freq_table = devm_kcalloc(devfreq->dev.parent,
>>> - count,
>>> - sizeof(*profile->freq_table),
>>> - GFP_KERNEL);
>>> - if (!profile->freq_table) {
>>> - profile->max_state = 0;
>>> + stats = devm_kzalloc(devfreq->dev.parent,
>>> + sizeof(struct devfreq_stats), GFP_KERNEL);
>>> + if (!stats)
>>> return -ENOMEM;
>>> - }
>>>
>>> - for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
>>> + profile->stats = stats;
>>> + stats->max_state = count;
>>> + stats->freq_table = devm_kcalloc(devfreq->dev.parent,
>>> + count,
>>> + sizeof(*stats->freq_table),
>>> + GFP_KERNEL);
>>> + if (!stats->freq_table)
>>> + goto err_no_mem;
>>> +
>>> + for (i = 0, freq = 0; i < count; i++, freq++) {
>>> opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
>>> if (IS_ERR(opp)) {
>>> - devm_kfree(devfreq->dev.parent, profile->freq_table);
>>> - profile->max_state = 0;
>>> - return PTR_ERR(opp);
>>> + devm_kfree(devfreq->dev.parent, stats->freq_table);
>>> + stats->max_state = 0;
>>> + err = PTR_ERR(opp);
>>> + goto err_no_mem;
>>> }
>>> dev_pm_opp_put(opp);
>>> - profile->freq_table[i] = freq;
>>> + stats->freq_table[i] = freq;
>>> }
>>>
>>> - profile->trans_table = devm_kzalloc(devfreq->dev.parent,
>>> - array3_size(sizeof(unsigned int),
>>> - count, count),
>>> - GFP_KERNEL);
>>> - if (!profile->trans_table)
>>> + stats->trans_table = devm_kzalloc(devfreq->dev.parent,
>>> + array3_size(sizeof(unsigned int),
>>> + count, count),
>>> + GFP_KERNEL);
>>> + if (!stats->trans_table)
>>> goto err_no_mem;
>>>
>>> - profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>>> - sizeof(*profile->time_in_state),
>>> - GFP_KERNEL);
>>> - if (!profile->time_in_state)
>>> + stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>>> + sizeof(*stats->time_in_state),
>>> + GFP_KERNEL);
>>> + if (!stats->time_in_state)
>>> goto err_no_mem;
>>>
>>> - profile->last_time = get_jiffies_64();
>>> - spin_lock_init(&profile->stats_lock);
>>> + stats->last_time = get_jiffies_64();
>>> + spin_lock_init(&stats->stats_lock);
>>>
>>> return 0;
>>> err_no_mem:
>>> - profile->max_state = 0;
>>> - return -ENOMEM;
>>> + stats->max_state = 0;
>>> + devm_kfree(devfreq->dev.parent, profile->stats);
>>> + profile->stats = NULL;
>>> + return err;
>>> }
>>>
>>> /**
>>> @@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq)
>>> */
>>> int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>> {
>>> - struct devfreq_dev_profile *profile = devfreq->profile;
>>> + struct devfreq_stats *stats = devfreq->profile->stats;
>>> unsigned long long cur_time;
>>> int lev, prev_lev, ret = 0;
>>>
>>> @@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>
>>> /* Immediately exit if previous_freq is not initialized yet. */
>>> if (!devfreq->previous_freq) {
>>> - spin_lock(&profile->stats_lock);
>>> - profile->last_time = cur_time;
>>> - spin_unlock(&profile->stats_lock);
>>> + spin_lock(&stats->stats_lock);
>>> + stats->last_time = cur_time;
>>> + spin_unlock(&stats->stats_lock);
>>> return 0;
>>> }
>>>
>>> prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq);
>>>
>>> - spin_lock(&profile->stats_lock);
>>> + spin_lock(&stats->stats_lock);
>>> if (prev_lev < 0) {
>>> ret = prev_lev;
>>> goto out;
>>> }
>>>
>>> - profile->time_in_state[prev_lev] +=
>>> - cur_time - profile->last_time;
>>> + stats->time_in_state[prev_lev] += cur_time - stats->last_time;
>>> lev = devfreq_get_freq_level(devfreq, freq);
>>> if (lev < 0) {
>>> ret = lev;
>>> @@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>> }
>>>
>>> if (lev != prev_lev) {
>>> - profile->trans_table[(prev_lev *
>>> - profile->max_state) + lev]++;
>>> - profile->total_trans++;
>>> + stats->trans_table[(prev_lev *
>>> + stats->max_state) + lev]++;
>>> + stats->total_trans++;
>>> }
>>>
>>> out:
>>> - profile->last_time = cur_time;
>>> - spin_unlock(&profile->stats_lock);
>>> + stats->last_time = cur_time;
>>> + spin_unlock(&stats->stats_lock);
>>> return ret;
>>> }
>>> EXPORT_SYMBOL(devfreq_update_status);
>>> @@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
>>> queue_delayed_work(devfreq_wq, &devfreq->work,
>>> msecs_to_jiffies(profile->polling_ms));
>>>
>>> - spin_lock(&profile->stats_lock);
>>> - profile->last_time = get_jiffies_64();
>>> - spin_unlock(&profile->stats_lock);
>>> + spin_lock(&profile->stats->stats_lock);
>>> + profile->stats->last_time = get_jiffies_64();
>>> + spin_unlock(&profile->stats->stats_lock);
>>> devfreq->stop_polling = false;
>>>
>>> if (profile->get_cur_freq &&
>>> @@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
>>> devfreq->data = data;
>>> devfreq->nb.notifier_call = devfreq_notifier_call;
>>>
>>> - if (!profile->max_state && !profile->freq_table) {
>>> + if (!profile->stats) {
>>> mutex_unlock(&devfreq->lock);
>>> err = set_freq_table(devfreq);
>>> if (err < 0)
>>> @@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>>> const char *buf, size_t count)
>>> {
>>> struct devfreq *df = to_devfreq(dev);
>>> + struct devfreq_stats *stats = df->profile->stats;
>>> unsigned long value;
>>> int ret;
>>>
>>> @@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>>> goto unlock;
>>> }
>>> } else {
>>> - unsigned long *freq_table = df->profile->freq_table;
>>> + unsigned long *freq_table = stats->freq_table;
>>>
>>> /* Get minimum frequency according to sorting order */
>>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>>> value = freq_table[0];
>>> else
>>> - value = freq_table[df->profile->max_state - 1];
>>> + value = freq_table[stats->max_state - 1];
>>> }
>>>
>>> df->min_freq = value;
>>> @@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>>> const char *buf, size_t count)
>>> {
>>> struct devfreq *df = to_devfreq(dev);
>>> + struct devfreq_stats *stats = df->profile->stats;
>>> unsigned long value;
>>> int ret;
>>>
>>> @@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>>> goto unlock;
>>> }
>>> } else {
>>> - unsigned long *freq_table = df->profile->freq_table;
>>> + unsigned long *freq_table = stats->freq_table;
>>>
>>> /* Get maximum frequency according to sorting order */
>>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>>> - value = freq_table[df->profile->max_state - 1];
>>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>>> + value = freq_table[stats->max_state - 1];
>>> else
>>> value = freq_table[0];
>>> }
>>> @@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d,
>>> char *buf)
>>> {
>>> struct devfreq *df = to_devfreq(d);
>>> + struct devfreq_stats *stats = df->profile->stats;
>>> ssize_t count = 0;
>>> int i;
>>>
>>> mutex_lock(&df->lock);
>>>
>>> - for (i = 0; i < df->profile->max_state; i++)
>>> + for (i = 0; i < stats->max_state; i++)
>>> count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
>>> - "%lu ", df->profile->freq_table[i]);
>>> + "%lu ", stats->freq_table[i]);
>>>
>>> mutex_unlock(&df->lock);
>>> /* Truncate the trailing space */
>>> @@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev,
>>> {
>>> struct devfreq *devfreq = to_devfreq(dev);
>>> struct devfreq_dev_profile *profile = devfreq->profile;
>>> + struct devfreq_stats *stats = profile->stats;
>>> + unsigned int max_state = stats->max_state;
>>> ssize_t len;
>>> int i, j;
>>> - unsigned int max_state = profile->max_state;
>>>
>>> if (!devfreq->stop_polling &&
>>> devfreq_update_status(devfreq, devfreq->previous_freq))
>>> @@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev,
>>> len = sprintf(buf, " From : To\n");
>>> len += sprintf(buf + len, " :");
>>>
>>> - spin_lock(&profile->stats_lock);
>>> + spin_lock(&stats->stats_lock);
>>> for (i = 0; i < max_state; i++)
>>> len += sprintf(buf + len, "%10lu",
>>> - profile->freq_table[i]);
>>> + stats->freq_table[i]);
>>>
>>> len += sprintf(buf + len, " time(ms)\n");
>>>
>>> for (i = 0; i < max_state; i++) {
>>> - if (profile->freq_table[i] == devfreq->previous_freq)
>>> + if (stats->freq_table[i] == devfreq->previous_freq)
>>> len += sprintf(buf + len, "*");
>>> else
>>> len += sprintf(buf + len, " ");
>>>
>>> len += sprintf(buf + len, "%10lu:",
>>> - profile->freq_table[i]);
>>> + stats->freq_table[i]);
>>> for (j = 0; j < max_state; j++)
>>> len += sprintf(buf + len, "%10u",
>>> - profile->trans_table[(i * max_state) + j]);
>>> + stats->trans_table[(i * max_state) + j]);
>>> len += sprintf(buf + len, "%10llu\n", (u64)
>>> - jiffies64_to_msecs(profile->time_in_state[i]));
>>> + jiffies64_to_msecs(stats->time_in_state[i]));
>>> }
>>>
>>> len += sprintf(buf + len, "Total transition : %u\n",
>>> - profile->total_trans);
>>> - spin_unlock(&profile->stats_lock);
>>> + stats->total_trans);
>>> + spin_unlock(&stats->stats_lock);
>>> return len;
>>> }
>>> static DEVICE_ATTR_RO(trans_stat);
>>>
>>> -static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile)
>>> +static void defvreq_stats_clear_table(struct devfreq_stats *stats)
>>> {
>>> - unsigned int count = profile->max_state;
>>> -
>>> - spin_lock(&profile->stats_lock);
>>> - memset(profile->time_in_state, 0, count * sizeof(u64));
>>> - memset(profile->trans_table, 0, count * count * sizeof(int));
>>> - profile->last_time = get_jiffies_64();
>>> - profile->total_trans = 0;
>>> - spin_unlock(&profile->stats_lock);
>>> + unsigned int count = stats->max_state;
>>> +
>>> + spin_lock(&stats->stats_lock);
>>> + memset(stats->time_in_state, 0, count * sizeof(u64));
>>> + memset(stats->trans_table, 0, count * count * sizeof(int));
>>> + stats->last_time = get_jiffies_64();
>>> + stats->total_trans = 0;
>>> + spin_unlock(&stats->stats_lock);
>>> }
>>>
>>> static ssize_t trans_reset_store(struct device *dev,
>>> @@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev,
>>> {
>>> struct devfreq *devfreq = to_devfreq(dev);
>>>
>>> - defvreq_stats_clear_table(devfreq->profile);
>>> + defvreq_stats_clear_table(devfreq->profile->stats);
>>>
>>> return count;
>>> }
>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>>> index d9f377912c10..b212aae2bb3e 100644
>>> --- a/drivers/devfreq/exynos-bus.c
>>> +++ b/drivers/devfreq/exynos-bus.c
>>> @@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
>>> }
>>>
>>> out:
>>> - max_state = bus->devfreq->profile->max_state;
>>> - min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
>>> - max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
>>> + max_state = profile->stats->max_state;
>>> + min_freq = (profile->stats->freq_table[0] / 1000);
>>> + max_freq = (profile->stats->freq_table[max_state - 1] / 1000);
>>> pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
>>> dev_name(dev), min_freq, max_freq);
>>>
>>> diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
>>> index 58308948b863..b2d87a88335c 100644
>>> --- a/drivers/devfreq/governor_passive.c
>>> +++ b/drivers/devfreq/governor_passive.c
>>> @@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>> struct devfreq_passive_data *p_data
>>> = (struct devfreq_passive_data *)devfreq->data;
>>> struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
>>> + struct devfreq_stats *parent_stats = parent_devfreq->profile->stats;
>>> + struct devfreq_stats *stats;
>>> unsigned long child_freq = ULONG_MAX;
>>> struct dev_pm_opp *opp;
>>> int i, count, ret = 0;
>>> @@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>> * device. And then the index is used for getting the suitable
>>> * new frequency for passive devfreq device.
>>> */
>>> - if (!devfreq->profile || !devfreq->profile->freq_table
>>> - || devfreq->profile->max_state <= 0)
>>> + if (!devfreq->profile || !devfreq->profile->stats ||
>>> + devfreq->profile->stats->max_state <= 0 ||
>>> + !parent_devfreq->profile || !parent_devfreq->profile->stats ||
>>> + parent_devfreq->profile->stats->max_state <= 0)
>>> return -EINVAL;
>>>
>>> + stats = devfreq->profile->stats;
>>> + parent_stats = parent_devfreq->profile->stats;
>>> /*
>>> * The passive governor have to get the correct frequency from OPP
>>> * list of parent device. Because in this case, *freq is temporary
>>> @@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>> * Get the OPP table's index of decided freqeuncy by governor
>>> * of parent device.
>>> */
>>> - for (i = 0; i < parent_devfreq->profile->max_state; i++)
>>> - if (parent_devfreq->profile->freq_table[i] == *freq)
>>> + for (i = 0; i < parent_stats->max_state; i++)
>>> + if (parent_stats->freq_table[i] == *freq)
>>> break;
>>>
>>> - if (i == parent_devfreq->profile->max_state) {
>>> + if (i == parent_stats->max_state) {
>>> ret = -EINVAL;
>>> goto out;
>>> }
>>>
>>> /* Get the suitable frequency by using index of parent device. */
>>> - if (i < devfreq->profile->max_state) {
>>> - child_freq = devfreq->profile->freq_table[i];
>>> + if (i < stats->max_state) {
>>> + child_freq = stats->freq_table[i];
>>> } else {
>>> - count = devfreq->profile->max_state;
>>> - child_freq = devfreq->profile->freq_table[count - 1];
>>> + count = stats->max_state;
>>> + child_freq = stats->freq_table[count - 1];
>>> }
>>>
>>> /* Return the suitable frequency for passive device. */
>>> @@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
>>> if (ret < 0)
>>> goto out;
>>>
>>> - if (devfreq->profile->freq_table
>>> + if (devfreq->profile->stats
>>> && (devfreq_update_status(devfreq, freq)))
>>> dev_err(&devfreq->dev,
>>> "Couldn't update frequency transition information.\n");
>>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>>> index 4ceb2a517a9c..8459af1a1583 100644
>>> --- a/include/linux/devfreq.h
>>> +++ b/include/linux/devfreq.h
>>> @@ -64,6 +64,30 @@ struct devfreq_dev_status {
>>> */
>>> #define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
>>>
>>> +/**
>>> + * struct devfreq_stats - Devfreq's transitions stats counters
>>> + * @freq_table: Optional list of frequencies to support statistics
>>> + * and freq_table must be generated in ascending order.
>>> + * @max_state: The size of freq_table.
>>> + * @total_trans: Number of devfreq transitions
>>> + * @trans_table: Statistics of devfreq transitions
>>> + * @time_in_state: Statistics of devfreq states
>>> + * @last_time: The last time stats were updated
>>> + * @stats_lock: Lock protecting trans_table, time_in_state,
>>> + * last_time and total_trans used for statistics
>>> + */
>>> +struct devfreq_stats {
>>> + unsigned long *freq_table;
>>> + unsigned int max_state;
>>> +
>>> + /* information for device frequency transition */
>>> + unsigned int total_trans;
>>> + unsigned int *trans_table;
>>> + u64 *time_in_state;
>>> + unsigned long long last_time;
>>> + spinlock_t stats_lock;
>>> +};
>>> +
>>> /**
>>> * struct devfreq_dev_profile - Devfreq's user device profile
>>> * @initial_freq: The operating frequency when devfreq_add_device() is
>>> @@ -88,15 +112,7 @@ struct devfreq_dev_status {
>>> * from devfreq_remove_device() call. If the user
>>> * has registered devfreq->nb at a notifier-head,
>>> * this is the time to unregister it.
>>> - * @freq_table: Optional list of frequencies to support statistics
>>> - * and freq_table must be generated in ascending order.
>>> - * @max_state: The size of freq_table.
>>> - * @total_trans: Number of devfreq transitions
>>> - * @trans_table: Statistics of devfreq transitions
>>> - * @time_in_state: Statistics of devfreq states
>>> - * @last_time: The last time stats were updated
>>> - * @stats_lock: Lock protecting trans_table, time_in_state,
>>> - * last_time and total_trans used for statistics
>>> + * @stats: Statistics of devfreq states and state transitions
>>> */
>>> struct devfreq_dev_profile {
>>> unsigned long initial_freq;
>>> @@ -108,14 +124,7 @@ struct devfreq_dev_profile {
>>> int (*get_cur_freq)(struct device *dev, unsigned long *freq);
>>> void (*exit)(struct device *dev);
>>>
>>> - unsigned long *freq_table;
>>> - unsigned int max_state;
>>> - /* information for device frequency transition */
>>> - unsigned int total_trans;
>>> - unsigned int *trans_table;
>>> - u64 *time_in_state;
>>> - unsigned long long last_time;
>>> - spinlock_t stats_lock;
>>> + struct devfreq_stats *stats;
>>> };
>>>
>>> /**
>>>
>
>
--
Best Regards,
Chanwoo Choi
Samsung Electronics
Hi Bartlomiej,
On 11/15/19 12:25 PM, Chanwoo Choi wrote:
> Hi Bartlomiej,
>
> On 11/15/19 3:01 AM, Bartlomiej Zolnierkiewicz wrote:
>>
>> Hi Chanwoo,
>>
>> On 11/14/19 2:52 AM, Chanwoo Choi wrote:
>>> Hi Kamil,
>>>
>>> The 'freq_table' and 'max_state' in the devfreq_dev_profile
>>> were used in the ARM Mali device driver[1][2][3]. Although ARM Mali
>>> device driver was posted to mainline kernel, they used
>>> them for a long time. It means that this patch break
>>> the compatibility. The ARM Mali drivers are very
>>> important devfreq device driver.
>>
>> This argument is not a a technical one and the official upstream
>> kernel policy is to not depend on out-of-tree drivers.
>>
>> Besides the ARM Mali drivers are full of code like:
>>
>> #if LINUX_VERSION_CODE >= KERNEL_VERSION(x, y, z)
>> ...
>> #else
>> ...
>> #endif
>>
>> so few more instances of similar code won't do any harm.. ;-)
>>
>>> [1] https://protect2.fireeye.com/url?k=909caa5c-cd52abe8-909d2113-000babdfecba-812f16576c3614a3&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/bifrost-kernel#
>>> [2] https://protect2.fireeye.com/url?k=33265f96-6ee85e22-3327d4d9-000babdfecba-44c2daec328712e6&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/midgard-kernel
>>> [3] https://protect2.fireeye.com/url?k=69bdcab0-3473cb04-69bc41ff-000babdfecba-4b576facf85e0208&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/utgard-kernel
>>
>> I took a look at ARM Mali drivers source code anyway and I fail to
>> see a rationale behind their behavior of doing 'freq_table' and
>> 'max_state' initialization in the driver itself (instead of leaving
>> it up to the devfreq core code, like all in-kernel drivers are doing
>> already).
>>
>> Could you please explain rationale behind ARM Mali drivers' special
>> needs?
>>
>> [ Both ARM Mali and devfreq core code are using generic PM OPP code
>> these days to do 'freq_table' and 'max_state' initialization, the
>> only difference seems to be that ARM Mali creates the frequency
>> table in the descending order (but there also seems to be no real
>> need for it). ]
>>
>> Maybe this is an opportunity to simplify also the ARM Mali driver?
>
> OK. I agree to simplify them on this time.
> For touching the 'freq_table' and 'max_state', need to fix
> the descending order of freq_table.
>
> The partition_enable_ops() in the drivers/thermal/devfreq_cooling.c
> requires the descending order of freq_table. Have to change it by using
> the ascending time or support both ascending and descending order for freq_table.
>
> 1. Move freq_table, max_state of devfreq_dev_profile to struct devfreq
> 2. Edit partition_enable_ops() in the drivers/thermal/devfreq_cooling.c
> by using ascending order instead of descending order.
>
After changed about 'freq_table' and 'max_state', the build error
will happen on ARM mail driver because the initialization code of
'freq_table' in ARM mali driver, didn't check the kernel version.
The first devfreq patch provided the 'freq_table' as optional variable
in the 'struct devfreq_dev_profile'. Even if ARM mali driver is out of mainline tree,
this change seems that break the usage rule of 'freq_table' in 'struct devfreq_dev_profile'.
So, if there are no any beneficial reason, I just keep the current status of 'freq_table'
in order to keep the previous usage rule of 'freq_table' in 'struct devfreq_dev_profile'.
Frankly, I'm note sure that it is necessary. I don't want to make
the side-effect without any useful reason.
But,
Separately, have to fix the ordering issue of partition_enable_ops()
in the drivers/thermal/devfreq_cooling.c.
>>
>>> Also, the devfreq device driver specifies their own
>>> information and data into devfreq_dev_profile structure
>>> before registering the devfreq device with devfreq_add_device().
>>> This patch breaks the basic usage rule of devfreq_dev_profile structure.
>>
>> Well, 'struct devfreq_stats *stats' can be trivially moved out of
>> 'struct devfreq_profile' to 'struct devfreq' if you prefer it that
>> way..
>>
>> Best regards,
>> --
>> Bartlomiej Zolnierkiewicz
>> Samsung R&D Institute Poland
>> Samsung Electronics
>>
>>> So, I can't agree this patch. Not ack.
>>>
>>> Regards,
>>> Chanwoo Choi
>>>
>>> On 11/13/19 6:13 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]>
>>>> ---
>>>> drivers/devfreq/devfreq.c | 156 ++++++++++++++++-------------
>>>> drivers/devfreq/exynos-bus.c | 6 +-
>>>> drivers/devfreq/governor_passive.c | 26 +++--
>>>> include/linux/devfreq.h | 43 ++++----
>>>> 4 files changed, 129 insertions(+), 102 deletions(-)
>>>>
>>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>>>> index d79412b0de59..d85867a91230 100644
>>>> --- a/drivers/devfreq/devfreq.c
>>>> +++ b/drivers/devfreq/devfreq.c
>>>> @@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
>>>> */
>>>> static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>>>> {
>>>> + struct devfreq_stats *stats = devfreq->profile->stats;
>>>> int lev;
>>>>
>>>> - for (lev = 0; lev < devfreq->profile->max_state; lev++)
>>>> - if (freq == devfreq->profile->freq_table[lev])
>>>> + for (lev = 0; lev < stats->max_state; lev++)
>>>> + if (freq == stats->freq_table[lev])
>>>> return lev;
>>>>
>>>> return -EINVAL;
>>>> @@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>>>> static int set_freq_table(struct devfreq *devfreq)
>>>> {
>>>> struct devfreq_dev_profile *profile = devfreq->profile;
>>>> + struct devfreq_stats *stats;
>>>> struct dev_pm_opp *opp;
>>>> unsigned long freq;
>>>> - int i, count;
>>>> + int i, count, err = -ENOMEM;
>>>>
>>>> /* Initialize the freq_table from OPP table */
>>>> count = dev_pm_opp_get_opp_count(devfreq->dev.parent);
>>>> if (count <= 0)
>>>> return -EINVAL;
>>>>
>>>> - profile->max_state = count;
>>>> - profile->freq_table = devm_kcalloc(devfreq->dev.parent,
>>>> - count,
>>>> - sizeof(*profile->freq_table),
>>>> - GFP_KERNEL);
>>>> - if (!profile->freq_table) {
>>>> - profile->max_state = 0;
>>>> + stats = devm_kzalloc(devfreq->dev.parent,
>>>> + sizeof(struct devfreq_stats), GFP_KERNEL);
>>>> + if (!stats)
>>>> return -ENOMEM;
>>>> - }
>>>>
>>>> - for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
>>>> + profile->stats = stats;
>>>> + stats->max_state = count;
>>>> + stats->freq_table = devm_kcalloc(devfreq->dev.parent,
>>>> + count,
>>>> + sizeof(*stats->freq_table),
>>>> + GFP_KERNEL);
>>>> + if (!stats->freq_table)
>>>> + goto err_no_mem;
>>>> +
>>>> + for (i = 0, freq = 0; i < count; i++, freq++) {
>>>> opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
>>>> if (IS_ERR(opp)) {
>>>> - devm_kfree(devfreq->dev.parent, profile->freq_table);
>>>> - profile->max_state = 0;
>>>> - return PTR_ERR(opp);
>>>> + devm_kfree(devfreq->dev.parent, stats->freq_table);
>>>> + stats->max_state = 0;
>>>> + err = PTR_ERR(opp);
>>>> + goto err_no_mem;
>>>> }
>>>> dev_pm_opp_put(opp);
>>>> - profile->freq_table[i] = freq;
>>>> + stats->freq_table[i] = freq;
>>>> }
>>>>
>>>> - profile->trans_table = devm_kzalloc(devfreq->dev.parent,
>>>> - array3_size(sizeof(unsigned int),
>>>> - count, count),
>>>> - GFP_KERNEL);
>>>> - if (!profile->trans_table)
>>>> + stats->trans_table = devm_kzalloc(devfreq->dev.parent,
>>>> + array3_size(sizeof(unsigned int),
>>>> + count, count),
>>>> + GFP_KERNEL);
>>>> + if (!stats->trans_table)
>>>> goto err_no_mem;
>>>>
>>>> - profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>>>> - sizeof(*profile->time_in_state),
>>>> - GFP_KERNEL);
>>>> - if (!profile->time_in_state)
>>>> + stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>>>> + sizeof(*stats->time_in_state),
>>>> + GFP_KERNEL);
>>>> + if (!stats->time_in_state)
>>>> goto err_no_mem;
>>>>
>>>> - profile->last_time = get_jiffies_64();
>>>> - spin_lock_init(&profile->stats_lock);
>>>> + stats->last_time = get_jiffies_64();
>>>> + spin_lock_init(&stats->stats_lock);
>>>>
>>>> return 0;
>>>> err_no_mem:
>>>> - profile->max_state = 0;
>>>> - return -ENOMEM;
>>>> + stats->max_state = 0;
>>>> + devm_kfree(devfreq->dev.parent, profile->stats);
>>>> + profile->stats = NULL;
>>>> + return err;
>>>> }
>>>>
>>>> /**
>>>> @@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq)
>>>> */
>>>> int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>> {
>>>> - struct devfreq_dev_profile *profile = devfreq->profile;
>>>> + struct devfreq_stats *stats = devfreq->profile->stats;
>>>> unsigned long long cur_time;
>>>> int lev, prev_lev, ret = 0;
>>>>
>>>> @@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>>
>>>> /* Immediately exit if previous_freq is not initialized yet. */
>>>> if (!devfreq->previous_freq) {
>>>> - spin_lock(&profile->stats_lock);
>>>> - profile->last_time = cur_time;
>>>> - spin_unlock(&profile->stats_lock);
>>>> + spin_lock(&stats->stats_lock);
>>>> + stats->last_time = cur_time;
>>>> + spin_unlock(&stats->stats_lock);
>>>> return 0;
>>>> }
>>>>
>>>> prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq);
>>>>
>>>> - spin_lock(&profile->stats_lock);
>>>> + spin_lock(&stats->stats_lock);
>>>> if (prev_lev < 0) {
>>>> ret = prev_lev;
>>>> goto out;
>>>> }
>>>>
>>>> - profile->time_in_state[prev_lev] +=
>>>> - cur_time - profile->last_time;
>>>> + stats->time_in_state[prev_lev] += cur_time - stats->last_time;
>>>> lev = devfreq_get_freq_level(devfreq, freq);
>>>> if (lev < 0) {
>>>> ret = lev;
>>>> @@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>> }
>>>>
>>>> if (lev != prev_lev) {
>>>> - profile->trans_table[(prev_lev *
>>>> - profile->max_state) + lev]++;
>>>> - profile->total_trans++;
>>>> + stats->trans_table[(prev_lev *
>>>> + stats->max_state) + lev]++;
>>>> + stats->total_trans++;
>>>> }
>>>>
>>>> out:
>>>> - profile->last_time = cur_time;
>>>> - spin_unlock(&profile->stats_lock);
>>>> + stats->last_time = cur_time;
>>>> + spin_unlock(&stats->stats_lock);
>>>> return ret;
>>>> }
>>>> EXPORT_SYMBOL(devfreq_update_status);
>>>> @@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
>>>> queue_delayed_work(devfreq_wq, &devfreq->work,
>>>> msecs_to_jiffies(profile->polling_ms));
>>>>
>>>> - spin_lock(&profile->stats_lock);
>>>> - profile->last_time = get_jiffies_64();
>>>> - spin_unlock(&profile->stats_lock);
>>>> + spin_lock(&profile->stats->stats_lock);
>>>> + profile->stats->last_time = get_jiffies_64();
>>>> + spin_unlock(&profile->stats->stats_lock);
>>>> devfreq->stop_polling = false;
>>>>
>>>> if (profile->get_cur_freq &&
>>>> @@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
>>>> devfreq->data = data;
>>>> devfreq->nb.notifier_call = devfreq_notifier_call;
>>>>
>>>> - if (!profile->max_state && !profile->freq_table) {
>>>> + if (!profile->stats) {
>>>> mutex_unlock(&devfreq->lock);
>>>> err = set_freq_table(devfreq);
>>>> if (err < 0)
>>>> @@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>>>> const char *buf, size_t count)
>>>> {
>>>> struct devfreq *df = to_devfreq(dev);
>>>> + struct devfreq_stats *stats = df->profile->stats;
>>>> unsigned long value;
>>>> int ret;
>>>>
>>>> @@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>>>> goto unlock;
>>>> }
>>>> } else {
>>>> - unsigned long *freq_table = df->profile->freq_table;
>>>> + unsigned long *freq_table = stats->freq_table;
>>>>
>>>> /* Get minimum frequency according to sorting order */
>>>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>>>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>>>> value = freq_table[0];
>>>> else
>>>> - value = freq_table[df->profile->max_state - 1];
>>>> + value = freq_table[stats->max_state - 1];
>>>> }
>>>>
>>>> df->min_freq = value;
>>>> @@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>>>> const char *buf, size_t count)
>>>> {
>>>> struct devfreq *df = to_devfreq(dev);
>>>> + struct devfreq_stats *stats = df->profile->stats;
>>>> unsigned long value;
>>>> int ret;
>>>>
>>>> @@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>>>> goto unlock;
>>>> }
>>>> } else {
>>>> - unsigned long *freq_table = df->profile->freq_table;
>>>> + unsigned long *freq_table = stats->freq_table;
>>>>
>>>> /* Get maximum frequency according to sorting order */
>>>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>>>> - value = freq_table[df->profile->max_state - 1];
>>>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>>>> + value = freq_table[stats->max_state - 1];
>>>> else
>>>> value = freq_table[0];
>>>> }
>>>> @@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d,
>>>> char *buf)
>>>> {
>>>> struct devfreq *df = to_devfreq(d);
>>>> + struct devfreq_stats *stats = df->profile->stats;
>>>> ssize_t count = 0;
>>>> int i;
>>>>
>>>> mutex_lock(&df->lock);
>>>>
>>>> - for (i = 0; i < df->profile->max_state; i++)
>>>> + for (i = 0; i < stats->max_state; i++)
>>>> count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
>>>> - "%lu ", df->profile->freq_table[i]);
>>>> + "%lu ", stats->freq_table[i]);
>>>>
>>>> mutex_unlock(&df->lock);
>>>> /* Truncate the trailing space */
>>>> @@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev,
>>>> {
>>>> struct devfreq *devfreq = to_devfreq(dev);
>>>> struct devfreq_dev_profile *profile = devfreq->profile;
>>>> + struct devfreq_stats *stats = profile->stats;
>>>> + unsigned int max_state = stats->max_state;
>>>> ssize_t len;
>>>> int i, j;
>>>> - unsigned int max_state = profile->max_state;
>>>>
>>>> if (!devfreq->stop_polling &&
>>>> devfreq_update_status(devfreq, devfreq->previous_freq))
>>>> @@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev,
>>>> len = sprintf(buf, " From : To\n");
>>>> len += sprintf(buf + len, " :");
>>>>
>>>> - spin_lock(&profile->stats_lock);
>>>> + spin_lock(&stats->stats_lock);
>>>> for (i = 0; i < max_state; i++)
>>>> len += sprintf(buf + len, "%10lu",
>>>> - profile->freq_table[i]);
>>>> + stats->freq_table[i]);
>>>>
>>>> len += sprintf(buf + len, " time(ms)\n");
>>>>
>>>> for (i = 0; i < max_state; i++) {
>>>> - if (profile->freq_table[i] == devfreq->previous_freq)
>>>> + if (stats->freq_table[i] == devfreq->previous_freq)
>>>> len += sprintf(buf + len, "*");
>>>> else
>>>> len += sprintf(buf + len, " ");
>>>>
>>>> len += sprintf(buf + len, "%10lu:",
>>>> - profile->freq_table[i]);
>>>> + stats->freq_table[i]);
>>>> for (j = 0; j < max_state; j++)
>>>> len += sprintf(buf + len, "%10u",
>>>> - profile->trans_table[(i * max_state) + j]);
>>>> + stats->trans_table[(i * max_state) + j]);
>>>> len += sprintf(buf + len, "%10llu\n", (u64)
>>>> - jiffies64_to_msecs(profile->time_in_state[i]));
>>>> + jiffies64_to_msecs(stats->time_in_state[i]));
>>>> }
>>>>
>>>> len += sprintf(buf + len, "Total transition : %u\n",
>>>> - profile->total_trans);
>>>> - spin_unlock(&profile->stats_lock);
>>>> + stats->total_trans);
>>>> + spin_unlock(&stats->stats_lock);
>>>> return len;
>>>> }
>>>> static DEVICE_ATTR_RO(trans_stat);
>>>>
>>>> -static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile)
>>>> +static void defvreq_stats_clear_table(struct devfreq_stats *stats)
>>>> {
>>>> - unsigned int count = profile->max_state;
>>>> -
>>>> - spin_lock(&profile->stats_lock);
>>>> - memset(profile->time_in_state, 0, count * sizeof(u64));
>>>> - memset(profile->trans_table, 0, count * count * sizeof(int));
>>>> - profile->last_time = get_jiffies_64();
>>>> - profile->total_trans = 0;
>>>> - spin_unlock(&profile->stats_lock);
>>>> + unsigned int count = stats->max_state;
>>>> +
>>>> + spin_lock(&stats->stats_lock);
>>>> + memset(stats->time_in_state, 0, count * sizeof(u64));
>>>> + memset(stats->trans_table, 0, count * count * sizeof(int));
>>>> + stats->last_time = get_jiffies_64();
>>>> + stats->total_trans = 0;
>>>> + spin_unlock(&stats->stats_lock);
>>>> }
>>>>
>>>> static ssize_t trans_reset_store(struct device *dev,
>>>> @@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev,
>>>> {
>>>> struct devfreq *devfreq = to_devfreq(dev);
>>>>
>>>> - defvreq_stats_clear_table(devfreq->profile);
>>>> + defvreq_stats_clear_table(devfreq->profile->stats);
>>>>
>>>> return count;
>>>> }
>>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>>>> index d9f377912c10..b212aae2bb3e 100644
>>>> --- a/drivers/devfreq/exynos-bus.c
>>>> +++ b/drivers/devfreq/exynos-bus.c
>>>> @@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
>>>> }
>>>>
>>>> out:
>>>> - max_state = bus->devfreq->profile->max_state;
>>>> - min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
>>>> - max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
>>>> + max_state = profile->stats->max_state;
>>>> + min_freq = (profile->stats->freq_table[0] / 1000);
>>>> + max_freq = (profile->stats->freq_table[max_state - 1] / 1000);
>>>> pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
>>>> dev_name(dev), min_freq, max_freq);
>>>>
>>>> diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
>>>> index 58308948b863..b2d87a88335c 100644
>>>> --- a/drivers/devfreq/governor_passive.c
>>>> +++ b/drivers/devfreq/governor_passive.c
>>>> @@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>>> struct devfreq_passive_data *p_data
>>>> = (struct devfreq_passive_data *)devfreq->data;
>>>> struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
>>>> + struct devfreq_stats *parent_stats = parent_devfreq->profile->stats;
>>>> + struct devfreq_stats *stats;
>>>> unsigned long child_freq = ULONG_MAX;
>>>> struct dev_pm_opp *opp;
>>>> int i, count, ret = 0;
>>>> @@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>>> * device. And then the index is used for getting the suitable
>>>> * new frequency for passive devfreq device.
>>>> */
>>>> - if (!devfreq->profile || !devfreq->profile->freq_table
>>>> - || devfreq->profile->max_state <= 0)
>>>> + if (!devfreq->profile || !devfreq->profile->stats ||
>>>> + devfreq->profile->stats->max_state <= 0 ||
>>>> + !parent_devfreq->profile || !parent_devfreq->profile->stats ||
>>>> + parent_devfreq->profile->stats->max_state <= 0)
>>>> return -EINVAL;
>>>>
>>>> + stats = devfreq->profile->stats;
>>>> + parent_stats = parent_devfreq->profile->stats;
>>>> /*
>>>> * The passive governor have to get the correct frequency from OPP
>>>> * list of parent device. Because in this case, *freq is temporary
>>>> @@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>>> * Get the OPP table's index of decided freqeuncy by governor
>>>> * of parent device.
>>>> */
>>>> - for (i = 0; i < parent_devfreq->profile->max_state; i++)
>>>> - if (parent_devfreq->profile->freq_table[i] == *freq)
>>>> + for (i = 0; i < parent_stats->max_state; i++)
>>>> + if (parent_stats->freq_table[i] == *freq)
>>>> break;
>>>>
>>>> - if (i == parent_devfreq->profile->max_state) {
>>>> + if (i == parent_stats->max_state) {
>>>> ret = -EINVAL;
>>>> goto out;
>>>> }
>>>>
>>>> /* Get the suitable frequency by using index of parent device. */
>>>> - if (i < devfreq->profile->max_state) {
>>>> - child_freq = devfreq->profile->freq_table[i];
>>>> + if (i < stats->max_state) {
>>>> + child_freq = stats->freq_table[i];
>>>> } else {
>>>> - count = devfreq->profile->max_state;
>>>> - child_freq = devfreq->profile->freq_table[count - 1];
>>>> + count = stats->max_state;
>>>> + child_freq = stats->freq_table[count - 1];
>>>> }
>>>>
>>>> /* Return the suitable frequency for passive device. */
>>>> @@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
>>>> if (ret < 0)
>>>> goto out;
>>>>
>>>> - if (devfreq->profile->freq_table
>>>> + if (devfreq->profile->stats
>>>> && (devfreq_update_status(devfreq, freq)))
>>>> dev_err(&devfreq->dev,
>>>> "Couldn't update frequency transition information.\n");
>>>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>>>> index 4ceb2a517a9c..8459af1a1583 100644
>>>> --- a/include/linux/devfreq.h
>>>> +++ b/include/linux/devfreq.h
>>>> @@ -64,6 +64,30 @@ struct devfreq_dev_status {
>>>> */
>>>> #define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
>>>>
>>>> +/**
>>>> + * struct devfreq_stats - Devfreq's transitions stats counters
>>>> + * @freq_table: Optional list of frequencies to support statistics
>>>> + * and freq_table must be generated in ascending order.
>>>> + * @max_state: The size of freq_table.
>>>> + * @total_trans: Number of devfreq transitions
>>>> + * @trans_table: Statistics of devfreq transitions
>>>> + * @time_in_state: Statistics of devfreq states
>>>> + * @last_time: The last time stats were updated
>>>> + * @stats_lock: Lock protecting trans_table, time_in_state,
>>>> + * last_time and total_trans used for statistics
>>>> + */
>>>> +struct devfreq_stats {
>>>> + unsigned long *freq_table;
>>>> + unsigned int max_state;
>>>> +
>>>> + /* information for device frequency transition */
>>>> + unsigned int total_trans;
>>>> + unsigned int *trans_table;
>>>> + u64 *time_in_state;
>>>> + unsigned long long last_time;
>>>> + spinlock_t stats_lock;
>>>> +};
>>>> +
>>>> /**
>>>> * struct devfreq_dev_profile - Devfreq's user device profile
>>>> * @initial_freq: The operating frequency when devfreq_add_device() is
>>>> @@ -88,15 +112,7 @@ struct devfreq_dev_status {
>>>> * from devfreq_remove_device() call. If the user
>>>> * has registered devfreq->nb at a notifier-head,
>>>> * this is the time to unregister it.
>>>> - * @freq_table: Optional list of frequencies to support statistics
>>>> - * and freq_table must be generated in ascending order.
>>>> - * @max_state: The size of freq_table.
>>>> - * @total_trans: Number of devfreq transitions
>>>> - * @trans_table: Statistics of devfreq transitions
>>>> - * @time_in_state: Statistics of devfreq states
>>>> - * @last_time: The last time stats were updated
>>>> - * @stats_lock: Lock protecting trans_table, time_in_state,
>>>> - * last_time and total_trans used for statistics
>>>> + * @stats: Statistics of devfreq states and state transitions
>>>> */
>>>> struct devfreq_dev_profile {
>>>> unsigned long initial_freq;
>>>> @@ -108,14 +124,7 @@ struct devfreq_dev_profile {
>>>> int (*get_cur_freq)(struct device *dev, unsigned long *freq);
>>>> void (*exit)(struct device *dev);
>>>>
>>>> - unsigned long *freq_table;
>>>> - unsigned int max_state;
>>>> - /* information for device frequency transition */
>>>> - unsigned int total_trans;
>>>> - unsigned int *trans_table;
>>>> - u64 *time_in_state;
>>>> - unsigned long long last_time;
>>>> - spinlock_t stats_lock;
>>>> + struct devfreq_stats *stats;
>>>> };
>>>>
>>>> /**
>>>>
>>
>>
>
>
--
Best Regards,
Chanwoo Choi
Samsung Electronics
[ added Zhang, Eduardo, Ørjan and Javi to Cc: ]
On 11/15/19 7:21 AM, Chanwoo Choi wrote:
> Hi Bartlomiej,
>
> On 11/15/19 12:25 PM, Chanwoo Choi wrote:
>> Hi Bartlomiej,
>>
>> On 11/15/19 3:01 AM, Bartlomiej Zolnierkiewicz wrote:
>>>
>>> Hi Chanwoo,
>>>
>>> On 11/14/19 2:52 AM, Chanwoo Choi wrote:
>>>> Hi Kamil,
>>>>
>>>> The 'freq_table' and 'max_state' in the devfreq_dev_profile
>>>> were used in the ARM Mali device driver[1][2][3]. Although ARM Mali
>>>> device driver was posted to mainline kernel, they used
>>>> them for a long time. It means that this patch break
>>>> the compatibility. The ARM Mali drivers are very
>>>> important devfreq device driver.
>>>
>>> This argument is not a a technical one and the official upstream
>>> kernel policy is to not depend on out-of-tree drivers.
>>>
>>> Besides the ARM Mali drivers are full of code like:
>>>
>>> #if LINUX_VERSION_CODE >= KERNEL_VERSION(x, y, z)
>>> ...
>>> #else
>>> ...
>>> #endif
>>>
>>> so few more instances of similar code won't do any harm.. ;-)
>>>
>>>> [1] https://protect2.fireeye.com/url?k=909caa5c-cd52abe8-909d2113-000babdfecba-812f16576c3614a3&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/bifrost-kernel#
>>>> [2] https://protect2.fireeye.com/url?k=33265f96-6ee85e22-3327d4d9-000babdfecba-44c2daec328712e6&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/midgard-kernel
>>>> [3] https://protect2.fireeye.com/url?k=69bdcab0-3473cb04-69bc41ff-000babdfecba-4b576facf85e0208&u=https://developer.arm.com/tools-and-software/graphics-and-gaming/mali-drivers/utgard-kernel
>>>
>>> I took a look at ARM Mali drivers source code anyway and I fail to
>>> see a rationale behind their behavior of doing 'freq_table' and
>>> 'max_state' initialization in the driver itself (instead of leaving
>>> it up to the devfreq core code, like all in-kernel drivers are doing
>>> already).
>>>
>>> Could you please explain rationale behind ARM Mali drivers' special
>>> needs?
>>>
>>> [ Both ARM Mali and devfreq core code are using generic PM OPP code
>>> these days to do 'freq_table' and 'max_state' initialization, the
>>> only difference seems to be that ARM Mali creates the frequency
>>> table in the descending order (but there also seems to be no real
>>> need for it). ]
>>>
>>> Maybe this is an opportunity to simplify also the ARM Mali driver?
>>
>> OK. I agree to simplify them on this time.
>> For touching the 'freq_table' and 'max_state', need to fix
>> the descending order of freq_table.
>>
>> The partition_enable_ops() in the drivers/thermal/devfreq_cooling.c
>> requires the descending order of freq_table. Have to change it by using
>> the ascending time or support both ascending and descending order for freq_table.
>>
>> 1. Move freq_table, max_state of devfreq_dev_profile to struct devfreq
>> 2. Edit partition_enable_ops() in the drivers/thermal/devfreq_cooling.c
>> by using ascending order instead of descending order.
>>
>
> After changed about 'freq_table' and 'max_state', the build error
> will happen on ARM mail driver because the initialization code of
> 'freq_table' in ARM mali driver, didn't check the kernel version.
>
> The first devfreq patch provided the 'freq_table' as optional variable
> in the 'struct devfreq_dev_profile'. Even if ARM mali driver is out of mainline tree,
> this change seems that break the usage rule of 'freq_table' in 'struct devfreq_dev_profile'.
>
> So, if there are no any beneficial reason, I just keep the current status of 'freq_table'
> in order to keep the previous usage rule of 'freq_table' in 'struct devfreq_dev_profile'.
>
> Frankly, I'm note sure that it is necessary. I don't want to make
> the side-effect without any useful reason.
>
> But,
> Separately, have to fix the ordering issue of partition_enable_ops()
> in the drivers/thermal/devfreq_cooling.c.
Hmmm.. fixing partition_enable_opps() should be trivial but I wonder
why we are carrying devfreq_cooling.c code in upstream kernel at all?
It has been merged in the following commit:
commit a76caf55e5b356ba20a5a43ac4d9f7a04b20941d
Author: Ørjan Eide <[email protected]>
Date: Thu Sep 10 18:09:30 2015 +0100
thermal: Add devfreq cooling
Add a generic thermal cooling device for devfreq, that is similar to
cpu_cooling.
The device must use devfreq. In order to use the power extension of the
cooling device, it must have registered its OPPs using the OPP library.
Cc: Zhang Rui <[email protected]>
Cc: Eduardo Valentin <[email protected]>
Signed-off-by: Javi Merino <[email protected]>
Signed-off-by: Ørjan Eide <[email protected]>
Signed-off-by: Eduardo Valentin <[email protected]>
...
but 4 years later there is still no single in-kernel user for this code?
Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics
>>>
>>>> Also, the devfreq device driver specifies their own
>>>> information and data into devfreq_dev_profile structure
>>>> before registering the devfreq device with devfreq_add_device().
>>>> This patch breaks the basic usage rule of devfreq_dev_profile structure.
>>>
>>> Well, 'struct devfreq_stats *stats' can be trivially moved out of
>>> 'struct devfreq_profile' to 'struct devfreq' if you prefer it that
>>> way..
>>>
>>> Best regards,
>>> --
>>> Bartlomiej Zolnierkiewicz
>>> Samsung R&D Institute Poland
>>> Samsung Electronics
>>>
>>>> So, I can't agree this patch. Not ack.
>>>>
>>>> Regards,
>>>> Chanwoo Choi
>>>>
>>>> On 11/13/19 6:13 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]>
>>>>> ---
>>>>> drivers/devfreq/devfreq.c | 156 ++++++++++++++++-------------
>>>>> drivers/devfreq/exynos-bus.c | 6 +-
>>>>> drivers/devfreq/governor_passive.c | 26 +++--
>>>>> include/linux/devfreq.h | 43 ++++----
>>>>> 4 files changed, 129 insertions(+), 102 deletions(-)
>>>>>
>>>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>>>>> index d79412b0de59..d85867a91230 100644
>>>>> --- a/drivers/devfreq/devfreq.c
>>>>> +++ b/drivers/devfreq/devfreq.c
>>>>> @@ -105,10 +105,11 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
>>>>> */
>>>>> static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>>>>> {
>>>>> + struct devfreq_stats *stats = devfreq->profile->stats;
>>>>> int lev;
>>>>>
>>>>> - for (lev = 0; lev < devfreq->profile->max_state; lev++)
>>>>> - if (freq == devfreq->profile->freq_table[lev])
>>>>> + for (lev = 0; lev < stats->max_state; lev++)
>>>>> + if (freq == stats->freq_table[lev])
>>>>> return lev;
>>>>>
>>>>> return -EINVAL;
>>>>> @@ -117,56 +118,64 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq)
>>>>> static int set_freq_table(struct devfreq *devfreq)
>>>>> {
>>>>> struct devfreq_dev_profile *profile = devfreq->profile;
>>>>> + struct devfreq_stats *stats;
>>>>> struct dev_pm_opp *opp;
>>>>> unsigned long freq;
>>>>> - int i, count;
>>>>> + int i, count, err = -ENOMEM;
>>>>>
>>>>> /* Initialize the freq_table from OPP table */
>>>>> count = dev_pm_opp_get_opp_count(devfreq->dev.parent);
>>>>> if (count <= 0)
>>>>> return -EINVAL;
>>>>>
>>>>> - profile->max_state = count;
>>>>> - profile->freq_table = devm_kcalloc(devfreq->dev.parent,
>>>>> - count,
>>>>> - sizeof(*profile->freq_table),
>>>>> - GFP_KERNEL);
>>>>> - if (!profile->freq_table) {
>>>>> - profile->max_state = 0;
>>>>> + stats = devm_kzalloc(devfreq->dev.parent,
>>>>> + sizeof(struct devfreq_stats), GFP_KERNEL);
>>>>> + if (!stats)
>>>>> return -ENOMEM;
>>>>> - }
>>>>>
>>>>> - for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
>>>>> + profile->stats = stats;
>>>>> + stats->max_state = count;
>>>>> + stats->freq_table = devm_kcalloc(devfreq->dev.parent,
>>>>> + count,
>>>>> + sizeof(*stats->freq_table),
>>>>> + GFP_KERNEL);
>>>>> + if (!stats->freq_table)
>>>>> + goto err_no_mem;
>>>>> +
>>>>> + for (i = 0, freq = 0; i < count; i++, freq++) {
>>>>> opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
>>>>> if (IS_ERR(opp)) {
>>>>> - devm_kfree(devfreq->dev.parent, profile->freq_table);
>>>>> - profile->max_state = 0;
>>>>> - return PTR_ERR(opp);
>>>>> + devm_kfree(devfreq->dev.parent, stats->freq_table);
>>>>> + stats->max_state = 0;
>>>>> + err = PTR_ERR(opp);
>>>>> + goto err_no_mem;
>>>>> }
>>>>> dev_pm_opp_put(opp);
>>>>> - profile->freq_table[i] = freq;
>>>>> + stats->freq_table[i] = freq;
>>>>> }
>>>>>
>>>>> - profile->trans_table = devm_kzalloc(devfreq->dev.parent,
>>>>> - array3_size(sizeof(unsigned int),
>>>>> - count, count),
>>>>> - GFP_KERNEL);
>>>>> - if (!profile->trans_table)
>>>>> + stats->trans_table = devm_kzalloc(devfreq->dev.parent,
>>>>> + array3_size(sizeof(unsigned int),
>>>>> + count, count),
>>>>> + GFP_KERNEL);
>>>>> + if (!stats->trans_table)
>>>>> goto err_no_mem;
>>>>>
>>>>> - profile->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>>>>> - sizeof(*profile->time_in_state),
>>>>> - GFP_KERNEL);
>>>>> - if (!profile->time_in_state)
>>>>> + stats->time_in_state = devm_kcalloc(devfreq->dev.parent, count,
>>>>> + sizeof(*stats->time_in_state),
>>>>> + GFP_KERNEL);
>>>>> + if (!stats->time_in_state)
>>>>> goto err_no_mem;
>>>>>
>>>>> - profile->last_time = get_jiffies_64();
>>>>> - spin_lock_init(&profile->stats_lock);
>>>>> + stats->last_time = get_jiffies_64();
>>>>> + spin_lock_init(&stats->stats_lock);
>>>>>
>>>>> return 0;
>>>>> err_no_mem:
>>>>> - profile->max_state = 0;
>>>>> - return -ENOMEM;
>>>>> + stats->max_state = 0;
>>>>> + devm_kfree(devfreq->dev.parent, profile->stats);
>>>>> + profile->stats = NULL;
>>>>> + return err;
>>>>> }
>>>>>
>>>>> /**
>>>>> @@ -176,7 +185,7 @@ static int set_freq_table(struct devfreq *devfreq)
>>>>> */
>>>>> int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>>> {
>>>>> - struct devfreq_dev_profile *profile = devfreq->profile;
>>>>> + struct devfreq_stats *stats = devfreq->profile->stats;
>>>>> unsigned long long cur_time;
>>>>> int lev, prev_lev, ret = 0;
>>>>>
>>>>> @@ -184,22 +193,21 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>>>
>>>>> /* Immediately exit if previous_freq is not initialized yet. */
>>>>> if (!devfreq->previous_freq) {
>>>>> - spin_lock(&profile->stats_lock);
>>>>> - profile->last_time = cur_time;
>>>>> - spin_unlock(&profile->stats_lock);
>>>>> + spin_lock(&stats->stats_lock);
>>>>> + stats->last_time = cur_time;
>>>>> + spin_unlock(&stats->stats_lock);
>>>>> return 0;
>>>>> }
>>>>>
>>>>> prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq);
>>>>>
>>>>> - spin_lock(&profile->stats_lock);
>>>>> + spin_lock(&stats->stats_lock);
>>>>> if (prev_lev < 0) {
>>>>> ret = prev_lev;
>>>>> goto out;
>>>>> }
>>>>>
>>>>> - profile->time_in_state[prev_lev] +=
>>>>> - cur_time - profile->last_time;
>>>>> + stats->time_in_state[prev_lev] += cur_time - stats->last_time;
>>>>> lev = devfreq_get_freq_level(devfreq, freq);
>>>>> if (lev < 0) {
>>>>> ret = lev;
>>>>> @@ -207,14 +215,14 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>>>>> }
>>>>>
>>>>> if (lev != prev_lev) {
>>>>> - profile->trans_table[(prev_lev *
>>>>> - profile->max_state) + lev]++;
>>>>> - profile->total_trans++;
>>>>> + stats->trans_table[(prev_lev *
>>>>> + stats->max_state) + lev]++;
>>>>> + stats->total_trans++;
>>>>> }
>>>>>
>>>>> out:
>>>>> - profile->last_time = cur_time;
>>>>> - spin_unlock(&profile->stats_lock);
>>>>> + stats->last_time = cur_time;
>>>>> + spin_unlock(&stats->stats_lock);
>>>>> return ret;
>>>>> }
>>>>> EXPORT_SYMBOL(devfreq_update_status);
>>>>> @@ -504,9 +512,9 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
>>>>> queue_delayed_work(devfreq_wq, &devfreq->work,
>>>>> msecs_to_jiffies(profile->polling_ms));
>>>>>
>>>>> - spin_lock(&profile->stats_lock);
>>>>> - profile->last_time = get_jiffies_64();
>>>>> - spin_unlock(&profile->stats_lock);
>>>>> + spin_lock(&profile->stats->stats_lock);
>>>>> + profile->stats->last_time = get_jiffies_64();
>>>>> + spin_unlock(&profile->stats->stats_lock);
>>>>> devfreq->stop_polling = false;
>>>>>
>>>>> if (profile->get_cur_freq &&
>>>>> @@ -677,7 +685,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
>>>>> devfreq->data = data;
>>>>> devfreq->nb.notifier_call = devfreq_notifier_call;
>>>>>
>>>>> - if (!profile->max_state && !profile->freq_table) {
>>>>> + if (!profile->stats) {
>>>>> mutex_unlock(&devfreq->lock);
>>>>> err = set_freq_table(devfreq);
>>>>> if (err < 0)
>>>>> @@ -1282,6 +1290,7 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>>>>> const char *buf, size_t count)
>>>>> {
>>>>> struct devfreq *df = to_devfreq(dev);
>>>>> + struct devfreq_stats *stats = df->profile->stats;
>>>>> unsigned long value;
>>>>> int ret;
>>>>>
>>>>> @@ -1297,13 +1306,13 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
>>>>> goto unlock;
>>>>> }
>>>>> } else {
>>>>> - unsigned long *freq_table = df->profile->freq_table;
>>>>> + unsigned long *freq_table = stats->freq_table;
>>>>>
>>>>> /* Get minimum frequency according to sorting order */
>>>>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>>>>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>>>>> value = freq_table[0];
>>>>> else
>>>>> - value = freq_table[df->profile->max_state - 1];
>>>>> + value = freq_table[stats->max_state - 1];
>>>>> }
>>>>>
>>>>> df->min_freq = value;
>>>>> @@ -1326,6 +1335,7 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>>>>> const char *buf, size_t count)
>>>>> {
>>>>> struct devfreq *df = to_devfreq(dev);
>>>>> + struct devfreq_stats *stats = df->profile->stats;
>>>>> unsigned long value;
>>>>> int ret;
>>>>>
>>>>> @@ -1341,11 +1351,11 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
>>>>> goto unlock;
>>>>> }
>>>>> } else {
>>>>> - unsigned long *freq_table = df->profile->freq_table;
>>>>> + unsigned long *freq_table = stats->freq_table;
>>>>>
>>>>> /* Get maximum frequency according to sorting order */
>>>>> - if (freq_table[0] < freq_table[df->profile->max_state - 1])
>>>>> - value = freq_table[df->profile->max_state - 1];
>>>>> + if (freq_table[0] < freq_table[stats->max_state - 1])
>>>>> + value = freq_table[stats->max_state - 1];
>>>>> else
>>>>> value = freq_table[0];
>>>>> }
>>>>> @@ -1373,14 +1383,15 @@ static ssize_t available_frequencies_show(struct device *d,
>>>>> char *buf)
>>>>> {
>>>>> struct devfreq *df = to_devfreq(d);
>>>>> + struct devfreq_stats *stats = df->profile->stats;
>>>>> ssize_t count = 0;
>>>>> int i;
>>>>>
>>>>> mutex_lock(&df->lock);
>>>>>
>>>>> - for (i = 0; i < df->profile->max_state; i++)
>>>>> + for (i = 0; i < stats->max_state; i++)
>>>>> count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
>>>>> - "%lu ", df->profile->freq_table[i]);
>>>>> + "%lu ", stats->freq_table[i]);
>>>>>
>>>>> mutex_unlock(&df->lock);
>>>>> /* Truncate the trailing space */
>>>>> @@ -1398,9 +1409,10 @@ static ssize_t trans_stat_show(struct device *dev,
>>>>> {
>>>>> struct devfreq *devfreq = to_devfreq(dev);
>>>>> struct devfreq_dev_profile *profile = devfreq->profile;
>>>>> + struct devfreq_stats *stats = profile->stats;
>>>>> + unsigned int max_state = stats->max_state;
>>>>> ssize_t len;
>>>>> int i, j;
>>>>> - unsigned int max_state = profile->max_state;
>>>>>
>>>>> if (!devfreq->stop_polling &&
>>>>> devfreq_update_status(devfreq, devfreq->previous_freq))
>>>>> @@ -1411,45 +1423,45 @@ static ssize_t trans_stat_show(struct device *dev,
>>>>> len = sprintf(buf, " From : To\n");
>>>>> len += sprintf(buf + len, " :");
>>>>>
>>>>> - spin_lock(&profile->stats_lock);
>>>>> + spin_lock(&stats->stats_lock);
>>>>> for (i = 0; i < max_state; i++)
>>>>> len += sprintf(buf + len, "%10lu",
>>>>> - profile->freq_table[i]);
>>>>> + stats->freq_table[i]);
>>>>>
>>>>> len += sprintf(buf + len, " time(ms)\n");
>>>>>
>>>>> for (i = 0; i < max_state; i++) {
>>>>> - if (profile->freq_table[i] == devfreq->previous_freq)
>>>>> + if (stats->freq_table[i] == devfreq->previous_freq)
>>>>> len += sprintf(buf + len, "*");
>>>>> else
>>>>> len += sprintf(buf + len, " ");
>>>>>
>>>>> len += sprintf(buf + len, "%10lu:",
>>>>> - profile->freq_table[i]);
>>>>> + stats->freq_table[i]);
>>>>> for (j = 0; j < max_state; j++)
>>>>> len += sprintf(buf + len, "%10u",
>>>>> - profile->trans_table[(i * max_state) + j]);
>>>>> + stats->trans_table[(i * max_state) + j]);
>>>>> len += sprintf(buf + len, "%10llu\n", (u64)
>>>>> - jiffies64_to_msecs(profile->time_in_state[i]));
>>>>> + jiffies64_to_msecs(stats->time_in_state[i]));
>>>>> }
>>>>>
>>>>> len += sprintf(buf + len, "Total transition : %u\n",
>>>>> - profile->total_trans);
>>>>> - spin_unlock(&profile->stats_lock);
>>>>> + stats->total_trans);
>>>>> + spin_unlock(&stats->stats_lock);
>>>>> return len;
>>>>> }
>>>>> static DEVICE_ATTR_RO(trans_stat);
>>>>>
>>>>> -static void defvreq_stats_clear_table(struct devfreq_dev_profile *profile)
>>>>> +static void defvreq_stats_clear_table(struct devfreq_stats *stats)
>>>>> {
>>>>> - unsigned int count = profile->max_state;
>>>>> -
>>>>> - spin_lock(&profile->stats_lock);
>>>>> - memset(profile->time_in_state, 0, count * sizeof(u64));
>>>>> - memset(profile->trans_table, 0, count * count * sizeof(int));
>>>>> - profile->last_time = get_jiffies_64();
>>>>> - profile->total_trans = 0;
>>>>> - spin_unlock(&profile->stats_lock);
>>>>> + unsigned int count = stats->max_state;
>>>>> +
>>>>> + spin_lock(&stats->stats_lock);
>>>>> + memset(stats->time_in_state, 0, count * sizeof(u64));
>>>>> + memset(stats->trans_table, 0, count * count * sizeof(int));
>>>>> + stats->last_time = get_jiffies_64();
>>>>> + stats->total_trans = 0;
>>>>> + spin_unlock(&stats->stats_lock);
>>>>> }
>>>>>
>>>>> static ssize_t trans_reset_store(struct device *dev,
>>>>> @@ -1459,7 +1471,7 @@ static ssize_t trans_reset_store(struct device *dev,
>>>>> {
>>>>> struct devfreq *devfreq = to_devfreq(dev);
>>>>>
>>>>> - defvreq_stats_clear_table(devfreq->profile);
>>>>> + defvreq_stats_clear_table(devfreq->profile->stats);
>>>>>
>>>>> return count;
>>>>> }
>>>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>>>>> index d9f377912c10..b212aae2bb3e 100644
>>>>> --- a/drivers/devfreq/exynos-bus.c
>>>>> +++ b/drivers/devfreq/exynos-bus.c
>>>>> @@ -496,9 +496,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
>>>>> }
>>>>>
>>>>> out:
>>>>> - max_state = bus->devfreq->profile->max_state;
>>>>> - min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
>>>>> - max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
>>>>> + max_state = profile->stats->max_state;
>>>>> + min_freq = (profile->stats->freq_table[0] / 1000);
>>>>> + max_freq = (profile->stats->freq_table[max_state - 1] / 1000);
>>>>> pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
>>>>> dev_name(dev), min_freq, max_freq);
>>>>>
>>>>> diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
>>>>> index 58308948b863..b2d87a88335c 100644
>>>>> --- a/drivers/devfreq/governor_passive.c
>>>>> +++ b/drivers/devfreq/governor_passive.c
>>>>> @@ -18,6 +18,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>>>> struct devfreq_passive_data *p_data
>>>>> = (struct devfreq_passive_data *)devfreq->data;
>>>>> struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
>>>>> + struct devfreq_stats *parent_stats = parent_devfreq->profile->stats;
>>>>> + struct devfreq_stats *stats;
>>>>> unsigned long child_freq = ULONG_MAX;
>>>>> struct dev_pm_opp *opp;
>>>>> int i, count, ret = 0;
>>>>> @@ -47,10 +49,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>>>> * device. And then the index is used for getting the suitable
>>>>> * new frequency for passive devfreq device.
>>>>> */
>>>>> - if (!devfreq->profile || !devfreq->profile->freq_table
>>>>> - || devfreq->profile->max_state <= 0)
>>>>> + if (!devfreq->profile || !devfreq->profile->stats ||
>>>>> + devfreq->profile->stats->max_state <= 0 ||
>>>>> + !parent_devfreq->profile || !parent_devfreq->profile->stats ||
>>>>> + parent_devfreq->profile->stats->max_state <= 0)
>>>>> return -EINVAL;
>>>>>
>>>>> + stats = devfreq->profile->stats;
>>>>> + parent_stats = parent_devfreq->profile->stats;
>>>>> /*
>>>>> * The passive governor have to get the correct frequency from OPP
>>>>> * list of parent device. Because in this case, *freq is temporary
>>>>> @@ -68,21 +74,21 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
>>>>> * Get the OPP table's index of decided freqeuncy by governor
>>>>> * of parent device.
>>>>> */
>>>>> - for (i = 0; i < parent_devfreq->profile->max_state; i++)
>>>>> - if (parent_devfreq->profile->freq_table[i] == *freq)
>>>>> + for (i = 0; i < parent_stats->max_state; i++)
>>>>> + if (parent_stats->freq_table[i] == *freq)
>>>>> break;
>>>>>
>>>>> - if (i == parent_devfreq->profile->max_state) {
>>>>> + if (i == parent_stats->max_state) {
>>>>> ret = -EINVAL;
>>>>> goto out;
>>>>> }
>>>>>
>>>>> /* Get the suitable frequency by using index of parent device. */
>>>>> - if (i < devfreq->profile->max_state) {
>>>>> - child_freq = devfreq->profile->freq_table[i];
>>>>> + if (i < stats->max_state) {
>>>>> + child_freq = stats->freq_table[i];
>>>>> } else {
>>>>> - count = devfreq->profile->max_state;
>>>>> - child_freq = devfreq->profile->freq_table[count - 1];
>>>>> + count = stats->max_state;
>>>>> + child_freq = stats->freq_table[count - 1];
>>>>> }
>>>>>
>>>>> /* Return the suitable frequency for passive device. */
>>>>> @@ -109,7 +115,7 @@ static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
>>>>> if (ret < 0)
>>>>> goto out;
>>>>>
>>>>> - if (devfreq->profile->freq_table
>>>>> + if (devfreq->profile->stats
>>>>> && (devfreq_update_status(devfreq, freq)))
>>>>> dev_err(&devfreq->dev,
>>>>> "Couldn't update frequency transition information.\n");
>>>>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>>>>> index 4ceb2a517a9c..8459af1a1583 100644
>>>>> --- a/include/linux/devfreq.h
>>>>> +++ b/include/linux/devfreq.h
>>>>> @@ -64,6 +64,30 @@ struct devfreq_dev_status {
>>>>> */
>>>>> #define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
>>>>>
>>>>> +/**
>>>>> + * struct devfreq_stats - Devfreq's transitions stats counters
>>>>> + * @freq_table: Optional list of frequencies to support statistics
>>>>> + * and freq_table must be generated in ascending order.
>>>>> + * @max_state: The size of freq_table.
>>>>> + * @total_trans: Number of devfreq transitions
>>>>> + * @trans_table: Statistics of devfreq transitions
>>>>> + * @time_in_state: Statistics of devfreq states
>>>>> + * @last_time: The last time stats were updated
>>>>> + * @stats_lock: Lock protecting trans_table, time_in_state,
>>>>> + * last_time and total_trans used for statistics
>>>>> + */
>>>>> +struct devfreq_stats {
>>>>> + unsigned long *freq_table;
>>>>> + unsigned int max_state;
>>>>> +
>>>>> + /* information for device frequency transition */
>>>>> + unsigned int total_trans;
>>>>> + unsigned int *trans_table;
>>>>> + u64 *time_in_state;
>>>>> + unsigned long long last_time;
>>>>> + spinlock_t stats_lock;
>>>>> +};
>>>>> +
>>>>> /**
>>>>> * struct devfreq_dev_profile - Devfreq's user device profile
>>>>> * @initial_freq: The operating frequency when devfreq_add_device() is
>>>>> @@ -88,15 +112,7 @@ struct devfreq_dev_status {
>>>>> * from devfreq_remove_device() call. If the user
>>>>> * has registered devfreq->nb at a notifier-head,
>>>>> * this is the time to unregister it.
>>>>> - * @freq_table: Optional list of frequencies to support statistics
>>>>> - * and freq_table must be generated in ascending order.
>>>>> - * @max_state: The size of freq_table.
>>>>> - * @total_trans: Number of devfreq transitions
>>>>> - * @trans_table: Statistics of devfreq transitions
>>>>> - * @time_in_state: Statistics of devfreq states
>>>>> - * @last_time: The last time stats were updated
>>>>> - * @stats_lock: Lock protecting trans_table, time_in_state,
>>>>> - * last_time and total_trans used for statistics
>>>>> + * @stats: Statistics of devfreq states and state transitions
>>>>> */
>>>>> struct devfreq_dev_profile {
>>>>> unsigned long initial_freq;
>>>>> @@ -108,14 +124,7 @@ struct devfreq_dev_profile {
>>>>> int (*get_cur_freq)(struct device *dev, unsigned long *freq);
>>>>> void (*exit)(struct device *dev);
>>>>>
>>>>> - unsigned long *freq_table;
>>>>> - unsigned int max_state;
>>>>> - /* information for device frequency transition */
>>>>> - unsigned int total_trans;
>>>>> - unsigned int *trans_table;
>>>>> - u64 *time_in_state;
>>>>> - unsigned long long last_time;
>>>>> - spinlock_t stats_lock;
>>>>> + struct devfreq_stats *stats;
>>>>> };
>>>>>
>>>>> /**
>>>>>
On 12/16/19 2:01 PM, Lukasz Luba wrote:
> Hi Bartek,
>
> [added Dietmar, Robin, Andrzej (for upcoming DRM drm-misc-next)]
>
> On 11/15/19 12:40 PM, Bartlomiej Zolnierkiewicz wrote:
[...]
>> Hmmm.. fixing partition_enable_opps() should be trivial but I wonder
>> why we are carrying devfreq_cooling.c code in upstream kernel at all?
>
> Well, the devfreq_cooling.c is going to have a client in mainline:
> the GPU driver - Panfrost.
>
> It is already in DRM branch 'drm-misc-next':
> https://patchwork.freedesktop.org/patch/342848/
OK, thanks for explaining this.
> Regarding the devfreq_cooling.c code structure.
> I am currently working on cleaning up the devfreq cooling code and
> adding Energy Model instead for private freq, power tables. It will be
> in similar fashion as it is done in cpufreq_cooling. The model will
> be also simplified so hopefully more clients would come.
> It is under internal review and will be posted shortly.
Great to hear this and thank you for working on it.
Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics