Add debugfs interface to provide debugging information of devfreq device.
It contains 'devfreq_summary' entry to show the summary of registered
devfreq devices as following and the additional debugfs file will be added.
- /sys/kernel/debug/devfreq/devfreq_summary
[Detailed description of each field of 'devfreq_summary' debugfs file]
- dev_name : Device name of h/w.
- dev : Device name made by devfreq core.
- parent_dev : If devfreq device uses the passive governor,
show parent devfreq device name.
- governor : Devfreq governor.
- polling_ms : If devfreq device uses the simple_ondemand governor,
polling_ms is necessary for the period. (unit: millisecond)
- cur_freq_Hz : Current Frequency (unit: Hz)
- old_freq_Hz : Frequency before changing. (unit: Hz)
- new_freq_Hz : Frequency after changed. (unit: Hz)
[For example on Exynos5422-based Odroid-XU3 board]
$ cat /sys/kernel/debug/devfreq/devfreq_summary
dev_name dev parent_dev governor polling_ms cur_freq_Hz min_freq_Hz max_freq_Hz
------------------------------ ---------- ---------- --------------- ---------- ------------ ------------ ------------
10c20000.memory-controller devfreq0 simple_ondemand 0 165000000 165000000 825000000
soc:bus_wcore devfreq1 simple_ondemand 50 532000000 88700000 532000000
soc:bus_noc devfreq2 devfreq1 passive 0 111000000 66600000 111000000
soc:bus_fsys_apb devfreq3 devfreq1 passive 0 222000000 111000000 222000000
soc:bus_fsys devfreq4 devfreq1 passive 0 200000000 75000000 200000000
soc:bus_fsys2 devfreq5 devfreq1 passive 0 200000000 75000000 200000000
soc:bus_mfc devfreq6 devfreq1 passive 0 333000000 83250000 333000000
soc:bus_gen devfreq7 devfreq1 passive 0 266000000 88700000 266000000
soc:bus_peri devfreq8 devfreq1 passive 0 66600000 66600000 66600000
soc:bus_g2d devfreq9 devfreq1 passive 0 333000000 83250000 333000000
soc:bus_g2d_acp devfreq10 devfreq1 passive 0 266000000 66500000 266000000
soc:bus_jpeg devfreq11 devfreq1 passive 0 300000000 75000000 300000000
soc:bus_jpeg_apb devfreq12 devfreq1 passive 0 166500000 83250000 166500000
soc:bus_disp1_fimd devfreq13 devfreq1 passive 0 200000000 120000000 200000000
soc:bus_disp1 devfreq14 devfreq1 passive 0 300000000 120000000 300000000
soc:bus_gscl_scaler devfreq15 devfreq1 passive 0 300000000 150000000 300000000
soc:bus_mscl devfreq16 devfreq1 passive 0 666000000 84000000 666000000
[lkp: Reported the build error]
Reported-by: kbuild test robot <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>
---
Changes from v1:
- Drop the patch about 'devfreq_transitions' debugfs file
- Modify from 'hz' to 'Hz'
- Edit the indentation of 'devfreq_summary' when show summary
- Exchange sequence between PTR_ERR and IS_ERR when debugfs_create_dir
drivers/devfreq/devfreq.c | 84 +++++++++++++++++++++++++++++++++++++++
1 file changed, 84 insertions(+)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 89260b17598f..c2ebed42704b 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -10,6 +10,7 @@
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/sched.h>
+#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/init.h>
@@ -33,6 +34,7 @@
#define HZ_PER_KHZ 1000
static struct class *devfreq_class;
+static struct dentry *devfreq_debugfs;
/*
* devfreq core provides delayed work based load monitoring helper
@@ -1643,6 +1645,79 @@ static struct attribute *devfreq_attrs[] = {
};
ATTRIBUTE_GROUPS(devfreq);
+/**
+ * devfreq_summary_show() - Show the summary of the devfreq devices
+ * @s: seq_file instance to show the summary of devfreq devices
+ * @data: not used
+ *
+ * Show the summary of the devfreq devices via 'devfreq_summary' debugfs file.
+ * It helps that user can know the detailed information of the devfreq devices.
+ *
+ * Return 0 always because it shows the information without any data change.
+ */
+static int devfreq_summary_show(struct seq_file *s, void *data)
+{
+ struct devfreq *devfreq;
+ struct devfreq *p_devfreq = NULL;
+ unsigned long cur_freq, min_freq, max_freq;
+ unsigned int polling_ms;
+
+ seq_printf(s, "%-30s %-10s %-10s %-15s %10s %12s %12s %12s\n",
+ "dev_name",
+ "dev",
+ "parent_dev",
+ "governor",
+ "polling_ms",
+ "cur_freq_Hz",
+ "min_freq_Hz",
+ "max_freq_Hz");
+ seq_printf(s, "%30s %10s %10s %15s %10s %12s %12s %12s\n",
+ "------------------------------",
+ "----------",
+ "----------",
+ "---------------",
+ "----------",
+ "------------",
+ "------------",
+ "------------");
+
+ mutex_lock(&devfreq_list_lock);
+
+ list_for_each_entry_reverse(devfreq, &devfreq_list, node) {
+ if (!strncmp(devfreq->governor_name, DEVFREQ_GOV_PASSIVE,
+ DEVFREQ_NAME_LEN)) {
+ struct devfreq_passive_data *data = devfreq->data;
+
+ if (data)
+ p_devfreq = data->parent;
+ } else {
+ p_devfreq = NULL;
+ }
+
+ mutex_lock(&devfreq->lock);
+ cur_freq = devfreq->previous_freq,
+ get_freq_range(devfreq, &min_freq, &max_freq);
+ polling_ms = devfreq->profile->polling_ms,
+ mutex_unlock(&devfreq->lock);
+
+ seq_printf(s,
+ "%-30s %-10s %-10s %-15s %10d %12ld %12ld %12ld\n",
+ dev_name(devfreq->dev.parent),
+ dev_name(&devfreq->dev),
+ p_devfreq ? dev_name(&p_devfreq->dev) : "",
+ devfreq->governor_name,
+ polling_ms,
+ cur_freq,
+ min_freq,
+ max_freq);
+ }
+
+ mutex_unlock(&devfreq_list_lock);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(devfreq_summary);
+
static int __init devfreq_init(void)
{
devfreq_class = class_create(THIS_MODULE, "devfreq");
@@ -1659,6 +1734,15 @@ static int __init devfreq_init(void)
}
devfreq_class->dev_groups = devfreq_groups;
+ devfreq_debugfs = debugfs_create_dir("devfreq", NULL);
+ if (IS_ERR(devfreq_debugfs) && PTR_ERR(devfreq_debugfs) != -ENODEV) {
+ pr_warn("%s: couldn't create debugfs dir\n", __FILE__);
+ } else {
+ debugfs_create_file("devfreq_summary", 0444,
+ devfreq_debugfs, NULL,
+ &devfreq_summary_fops);
+ }
+
return 0;
}
subsys_initcall(devfreq_init);
--
2.17.1
On 13.01.2020 06:56, Chanwoo Choi wrote:
> Add debugfs interface to provide debugging information of devfreq device.
> It contains 'devfreq_summary' entry to show the summary of registered
> devfreq devices as following and the additional debugfs file will be added.
> - /sys/kernel/debug/devfreq/devfreq_summary
>
> [Detailed description of each field of 'devfreq_summary' debugfs file]
> - dev_name : Device name of h/w.
> - dev : Device name made by devfreq core.
> - parent_dev : If devfreq device uses the passive governor,
> show parent devfreq device name.
> - governor : Devfreq governor.
> - polling_ms : If devfreq device uses the simple_ondemand governor,
> polling_ms is necessary for the period. (unit: millisecond)
> - cur_freq_Hz : Current Frequency (unit: Hz)
> - old_freq_Hz : Frequency before changing. (unit: Hz)
> - new_freq_Hz : Frequency after changed. (unit: Hz)
>
> [For example on Exynos5422-based Odroid-XU3 board]
> $ cat /sys/kernel/debug/devfreq/devfreq_summary
> dev_name dev parent_dev governor polling_ms cur_freq_Hz min_freq_Hz max_freq_Hz
> ------------------------------ ---------- ---------- --------------- ---------- ------------ ------------ ------------
> 10c20000.memory-controller devfreq0 simple_ondemand 0 165000000 165000000 825000000
> soc:bus_wcore devfreq1 simple_ondemand 50 532000000 88700000 532000000
> soc:bus_noc devfreq2 devfreq1 passive 0 111000000 66600000 111000000
> soc:bus_fsys_apb devfreq3 devfreq1 passive 0 222000000 111000000 222000000
> soc:bus_fsys devfreq4 devfreq1 passive 0 200000000 75000000 200000000
> soc:bus_fsys2 devfreq5 devfreq1 passive 0 200000000 75000000 200000000
> soc:bus_mfc devfreq6 devfreq1 passive 0 333000000 83250000 333000000
> soc:bus_gen devfreq7 devfreq1 passive 0 266000000 88700000 266000000
> soc:bus_peri devfreq8 devfreq1 passive 0 66600000 66600000 66600000
> soc:bus_g2d devfreq9 devfreq1 passive 0 333000000 83250000 333000000
> soc:bus_g2d_acp devfreq10 devfreq1 passive 0 266000000 66500000 266000000
> soc:bus_jpeg devfreq11 devfreq1 passive 0 300000000 75000000 300000000
> soc:bus_jpeg_apb devfreq12 devfreq1 passive 0 166500000 83250000 166500000
> soc:bus_disp1_fimd devfreq13 devfreq1 passive 0 200000000 120000000 200000000
> soc:bus_disp1 devfreq14 devfreq1 passive 0 300000000 120000000 300000000
> soc:bus_gscl_scaler devfreq15 devfreq1 passive 0 300000000 150000000 300000000
> soc:bus_mscl devfreq16 devfreq1 passive 0 666000000 84000000 666000000
>
> [lkp: Reported the build error]
> Reported-by: kbuild test robot <[email protected]>
> Signed-off-by: Chanwoo Choi <[email protected]>
> ---
> Changes from v1:
> - Drop the patch about 'devfreq_transitions' debugfs file
> - Modify from 'hz' to 'Hz'
> - Edit the indentation of 'devfreq_summary' when show summary
> - Exchange sequence between PTR_ERR and IS_ERR when debugfs_create_dir
>
> drivers/devfreq/devfreq.c | 84 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 84 insertions(+)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 89260b17598f..c2ebed42704b 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -10,6 +10,7 @@
> #include <linux/kernel.h>
> #include <linux/kmod.h>
> #include <linux/sched.h>
> +#include <linux/debugfs.h>
> #include <linux/errno.h>
> #include <linux/err.h>
> #include <linux/init.h>
> @@ -33,6 +34,7 @@
> #define HZ_PER_KHZ 1000
>
> static struct class *devfreq_class;
> +static struct dentry *devfreq_debugfs;
>
> /*
> * devfreq core provides delayed work based load monitoring helper
> @@ -1643,6 +1645,79 @@ static struct attribute *devfreq_attrs[] = {
> };
> ATTRIBUTE_GROUPS(devfreq);
>
> +/**
> + * devfreq_summary_show() - Show the summary of the devfreq devices
> + * @s: seq_file instance to show the summary of devfreq devices
> + * @data: not used
> + *
> + * Show the summary of the devfreq devices via 'devfreq_summary' debugfs file.
> + * It helps that user can know the detailed information of the devfreq devices.
> + *
> + * Return 0 always because it shows the information without any data change.
> + */
> +static int devfreq_summary_show(struct seq_file *s, void *data)
> +{
> + struct devfreq *devfreq;
> + struct devfreq *p_devfreq = NULL;
> + unsigned long cur_freq, min_freq, max_freq;
> + unsigned int polling_ms;
> +
> + seq_printf(s, "%-30s %-10s %-10s %-15s %10s %12s %12s %12s\n",
> + "dev_name",
> + "dev",
> + "parent_dev",
> + "governor",
> + "polling_ms",
> + "cur_freq_Hz",
> + "min_freq_Hz",
> + "max_freq_Hz");
> + seq_printf(s, "%30s %10s %10s %15s %10s %12s %12s %12s\n",
> + "------------------------------",
> + "----------",
> + "----------",
> + "---------------",
> + "----------",
> + "------------",
> + "------------",
> + "------------");
> +
> + mutex_lock(&devfreq_list_lock);
> +
> + list_for_each_entry_reverse(devfreq, &devfreq_list, node) {
> + if (!strncmp(devfreq->governor_name, DEVFREQ_GOV_PASSIVE,
> + DEVFREQ_NAME_LEN)) {
> + struct devfreq_passive_data *data = devfreq->data;
> +
> + if (data)
> + p_devfreq = data->parent;
> + } else {
> + p_devfreq = NULL;
> + }
> +
> + mutex_lock(&devfreq->lock);
> + cur_freq = devfreq->previous_freq,
> + get_freq_range(devfreq, &min_freq, &max_freq);
> + polling_ms = devfreq->profile->polling_ms,
> + mutex_unlock(&devfreq->lock);
> +
> + seq_printf(s,
> + "%-30s %-10s %-10s %-15s %10d %12ld %12ld %12ld\n",
> + dev_name(devfreq->dev.parent),
> + dev_name(&devfreq->dev),
> + p_devfreq ? dev_name(&p_devfreq->dev) : "",
Can you prints some sort of "null" here instead of just skipping the field?
This would ensure output is always a whitespace-separated table that can
be easily processed with tools like "awk".
> + devfreq->governor_name,
> + polling_ms,
> + cur_freq,
> + min_freq,
> + max_freq);
> + }
> +
> + mutex_unlock(&devfreq_list_lock);
> +
> + return 0;
> +}
> +DEFINE_SHOW_ATTRIBUTE(devfreq_summary);
> +
> static int __init devfreq_init(void)
> {
> devfreq_class = class_create(THIS_MODULE, "devfreq");
> @@ -1659,6 +1734,15 @@ static int __init devfreq_init(void)
> }
> devfreq_class->dev_groups = devfreq_groups;
>
> + devfreq_debugfs = debugfs_create_dir("devfreq", NULL);
> + if (IS_ERR(devfreq_debugfs) && PTR_ERR(devfreq_debugfs) != -ENODEV) {
> + pr_warn("%s: couldn't create debugfs dir\n", __FILE__); > + } else {
> + debugfs_create_file("devfreq_summary", 0444,
> + devfreq_debugfs, NULL,
> + &devfreq_summary_fops);
> + }
> +
> return 0;
> }
> subsys_initcall(devfreq_init);
>
On 1/14/20 3:18 AM, Leonard Crestez wrote:
> On 13.01.2020 06:56, Chanwoo Choi wrote:
>> Add debugfs interface to provide debugging information of devfreq device.
>> It contains 'devfreq_summary' entry to show the summary of registered
>> devfreq devices as following and the additional debugfs file will be added.
>> - /sys/kernel/debug/devfreq/devfreq_summary
>>
>> [Detailed description of each field of 'devfreq_summary' debugfs file]
>> - dev_name : Device name of h/w.
>> - dev : Device name made by devfreq core.
>> - parent_dev : If devfreq device uses the passive governor,
>> show parent devfreq device name.
>> - governor : Devfreq governor.
>> - polling_ms : If devfreq device uses the simple_ondemand governor,
>> polling_ms is necessary for the period. (unit: millisecond)
>> - cur_freq_Hz : Current Frequency (unit: Hz)
>> - old_freq_Hz : Frequency before changing. (unit: Hz)
>> - new_freq_Hz : Frequency after changed. (unit: Hz)
>>
>> [For example on Exynos5422-based Odroid-XU3 board]
>> $ cat /sys/kernel/debug/devfreq/devfreq_summary
>> dev_name dev parent_dev governor polling_ms cur_freq_Hz min_freq_Hz max_freq_Hz
>> ------------------------------ ---------- ---------- --------------- ---------- ------------ ------------ ------------
>> 10c20000.memory-controller devfreq0 simple_ondemand 0 165000000 165000000 825000000
>> soc:bus_wcore devfreq1 simple_ondemand 50 532000000 88700000 532000000
>> soc:bus_noc devfreq2 devfreq1 passive 0 111000000 66600000 111000000
>> soc:bus_fsys_apb devfreq3 devfreq1 passive 0 222000000 111000000 222000000
>> soc:bus_fsys devfreq4 devfreq1 passive 0 200000000 75000000 200000000
>> soc:bus_fsys2 devfreq5 devfreq1 passive 0 200000000 75000000 200000000
>> soc:bus_mfc devfreq6 devfreq1 passive 0 333000000 83250000 333000000
>> soc:bus_gen devfreq7 devfreq1 passive 0 266000000 88700000 266000000
>> soc:bus_peri devfreq8 devfreq1 passive 0 66600000 66600000 66600000
>> soc:bus_g2d devfreq9 devfreq1 passive 0 333000000 83250000 333000000
>> soc:bus_g2d_acp devfreq10 devfreq1 passive 0 266000000 66500000 266000000
>> soc:bus_jpeg devfreq11 devfreq1 passive 0 300000000 75000000 300000000
>> soc:bus_jpeg_apb devfreq12 devfreq1 passive 0 166500000 83250000 166500000
>> soc:bus_disp1_fimd devfreq13 devfreq1 passive 0 200000000 120000000 200000000
>> soc:bus_disp1 devfreq14 devfreq1 passive 0 300000000 120000000 300000000
>> soc:bus_gscl_scaler devfreq15 devfreq1 passive 0 300000000 150000000 300000000
>> soc:bus_mscl devfreq16 devfreq1 passive 0 666000000 84000000 666000000
>>
>> [lkp: Reported the build error]
>> Reported-by: kbuild test robot <[email protected]>
>> Signed-off-by: Chanwoo Choi <[email protected]>
>> ---
>> Changes from v1:
>> - Drop the patch about 'devfreq_transitions' debugfs file
>> - Modify from 'hz' to 'Hz'
>> - Edit the indentation of 'devfreq_summary' when show summary
>> - Exchange sequence between PTR_ERR and IS_ERR when debugfs_create_dir
>>
>> drivers/devfreq/devfreq.c | 84 +++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 84 insertions(+)
>>
>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>> index 89260b17598f..c2ebed42704b 100644
>> --- a/drivers/devfreq/devfreq.c
>> +++ b/drivers/devfreq/devfreq.c
>> @@ -10,6 +10,7 @@
>> #include <linux/kernel.h>
>> #include <linux/kmod.h>
>> #include <linux/sched.h>
>> +#include <linux/debugfs.h>
>> #include <linux/errno.h>
>> #include <linux/err.h>
>> #include <linux/init.h>
>> @@ -33,6 +34,7 @@
>> #define HZ_PER_KHZ 1000
>>
>> static struct class *devfreq_class;
>> +static struct dentry *devfreq_debugfs;
>>
>> /*
>> * devfreq core provides delayed work based load monitoring helper
>> @@ -1643,6 +1645,79 @@ static struct attribute *devfreq_attrs[] = {
>> };
>> ATTRIBUTE_GROUPS(devfreq);
>>
>> +/**
>> + * devfreq_summary_show() - Show the summary of the devfreq devices
>> + * @s: seq_file instance to show the summary of devfreq devices
>> + * @data: not used
>> + *
>> + * Show the summary of the devfreq devices via 'devfreq_summary' debugfs file.
>> + * It helps that user can know the detailed information of the devfreq devices.
>> + *
>> + * Return 0 always because it shows the information without any data change.
>> + */
>> +static int devfreq_summary_show(struct seq_file *s, void *data)
>> +{
>> + struct devfreq *devfreq;
>> + struct devfreq *p_devfreq = NULL;
>> + unsigned long cur_freq, min_freq, max_freq;
>> + unsigned int polling_ms;
>> +
>> + seq_printf(s, "%-30s %-10s %-10s %-15s %10s %12s %12s %12s\n",
>> + "dev_name",
>> + "dev",
>> + "parent_dev",
>> + "governor",
>> + "polling_ms",
>> + "cur_freq_Hz",
>> + "min_freq_Hz",
>> + "max_freq_Hz");
>> + seq_printf(s, "%30s %10s %10s %15s %10s %12s %12s %12s\n",
>> + "------------------------------",
>> + "----------",
>> + "----------",
>> + "---------------",
>> + "----------",
>> + "------------",
>> + "------------",
>> + "------------");
>> +
>> + mutex_lock(&devfreq_list_lock);
>> +
>> + list_for_each_entry_reverse(devfreq, &devfreq_list, node) {
>> + if (!strncmp(devfreq->governor_name, DEVFREQ_GOV_PASSIVE,
>> + DEVFREQ_NAME_LEN)) {
>> + struct devfreq_passive_data *data = devfreq->data;
>> +
>> + if (data)
>> + p_devfreq = data->parent;
>> + } else {
>> + p_devfreq = NULL;
>> + }
>> +
>> + mutex_lock(&devfreq->lock);
>> + cur_freq = devfreq->previous_freq,
>> + get_freq_range(devfreq, &min_freq, &max_freq);
>> + polling_ms = devfreq->profile->polling_ms,
>> + mutex_unlock(&devfreq->lock);
>> +
>> + seq_printf(s,
>> + "%-30s %-10s %-10s %-15s %10d %12ld %12ld %12ld\n",
>> + dev_name(devfreq->dev.parent),
>> + dev_name(&devfreq->dev),
>> + p_devfreq ? dev_name(&p_devfreq->dev) : "",
>
> Can you prints some sort of "null" here instead of just skipping the field?
>
> This would ensure output is always a whitespace-separated table that can
> be easily processed with tools like "awk".
OK.
I had considered what is better to show 'null' or not.
If there is requirement, print 'null'.
>
>> + devfreq->governor_name,
>> + polling_ms,
>> + cur_freq,
>> + min_freq,
>> + max_freq);
>> + }
>> +
>> + mutex_unlock(&devfreq_list_lock);
>> +
>> + return 0;
>> +}
>> +DEFINE_SHOW_ATTRIBUTE(devfreq_summary);
>> +
>> static int __init devfreq_init(void)
>> {
>> devfreq_class = class_create(THIS_MODULE, "devfreq");
>> @@ -1659,6 +1734,15 @@ static int __init devfreq_init(void)
>> }
>> devfreq_class->dev_groups = devfreq_groups;
>>
>> + devfreq_debugfs = debugfs_create_dir("devfreq", NULL);
>> + if (IS_ERR(devfreq_debugfs) && PTR_ERR(devfreq_debugfs) != -ENODEV) {
>> + pr_warn("%s: couldn't create debugfs dir\n", __FILE__); > + } else {
>> + debugfs_create_file("devfreq_summary", 0444,
>> + devfreq_debugfs, NULL,
>> + &devfreq_summary_fops);
>> + }
>> +
>> return 0;
>> }
>> subsys_initcall(devfreq_init);
>>
>
>
>
--
Best Regards,
Chanwoo Choi
Samsung Electronics