PM: Add sysfs files to represent time spent in hardware sleep state

Userspace can't easily discover how much of a sleep cycle was spent in a
hardware sleep state without using kernel tracing and vendor specific sysfs
or debugfs files.

To make this information more discoverable, introduce 3 new sysfs files:
1) The time spent in a hw sleep state for last cycle.
2) The time spent in a hw sleep state since the kernel booted
3) The maximum time that the hardware can report for a sleep cycle.
All of these files will be present only if the system supports s2idle.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Mario Limonciello 2023-04-17 10:27:05 -05:00 committed by Rafael J. Wysocki
parent 6a8f57ae2e
commit b52124a78a
3 changed files with 84 additions and 12 deletions

View File

@ -413,6 +413,35 @@ Description:
The /sys/power/suspend_stats/last_failed_step file contains
the last failed step in the suspend/resume path.
What: /sys/power/suspend_stats/last_hw_sleep
Date: June 2023
Contact: Mario Limonciello <mario.limonciello@amd.com>
Description:
The /sys/power/suspend_stats/last_hw_sleep file
contains the duration of time spent in a hardware sleep
state in the most recent system suspend-resume cycle.
This number is measured in microseconds.
What: /sys/power/suspend_stats/total_hw_sleep
Date: June 2023
Contact: Mario Limonciello <mario.limonciello@amd.com>
Description:
The /sys/power/suspend_stats/total_hw_sleep file
contains the aggregate of time spent in a hardware sleep
state since the kernel was booted. This number
is measured in microseconds.
What: /sys/power/suspend_stats/max_hw_sleep
Date: June 2023
Contact: Mario Limonciello <mario.limonciello@amd.com>
Description:
The /sys/power/suspend_stats/max_hw_sleep file
contains the maximum amount of time that the hardware can
report for time spent in a hardware sleep state. When sleep
cycles are longer than this time, the values for
'total_hw_sleep' and 'last_hw_sleep' may not be accurate.
This number is measured in microseconds.
What: /sys/power/sync_on_suspend
Date: October 2019
Contact: Jonas Meurer <jonas@freesources.org>

View File

@ -68,6 +68,9 @@ struct suspend_stats {
int last_failed_errno;
int errno[REC_FAILED_NUM];
int last_failed_step;
u64 last_hw_sleep;
u64 total_hw_sleep;
u64 max_hw_sleep;
enum suspend_stat_step failed_steps[REC_FAILED_NUM];
};
@ -489,6 +492,8 @@ void restore_processor_state(void);
extern int register_pm_notifier(struct notifier_block *nb);
extern int unregister_pm_notifier(struct notifier_block *nb);
extern void ksys_sync_helper(void);
extern void pm_report_hw_sleep_time(u64 t);
extern void pm_report_max_hw_sleep(u64 t);
#define pm_notifier(fn, pri) { \
static struct notifier_block fn##_nb = \
@ -526,6 +531,9 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
return 0;
}
static inline void pm_report_hw_sleep_time(u64 t) {};
static inline void pm_report_max_hw_sleep(u64 t) {};
static inline void ksys_sync_helper(void) {}
#define pm_notifier(fn, pri) do { (void)(fn); } while (0)

View File

@ -6,6 +6,7 @@
* Copyright (c) 2003 Open Source Development Lab
*/
#include <linux/acpi.h>
#include <linux/export.h>
#include <linux/kobject.h>
#include <linux/string.h>
@ -83,6 +84,19 @@ int unregister_pm_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL_GPL(unregister_pm_notifier);
void pm_report_hw_sleep_time(u64 t)
{
suspend_stats.last_hw_sleep = t;
suspend_stats.total_hw_sleep += t;
}
EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time);
void pm_report_max_hw_sleep(u64 t)
{
suspend_stats.max_hw_sleep = t;
}
EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep);
int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
{
int ret;
@ -314,24 +328,27 @@ static char *suspend_step_name(enum suspend_stat_step step)
}
}
#define suspend_attr(_name) \
#define suspend_attr(_name, format_str) \
static ssize_t _name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%d\n", suspend_stats._name); \
return sprintf(buf, format_str, suspend_stats._name); \
} \
static struct kobj_attribute _name = __ATTR_RO(_name)
suspend_attr(success);
suspend_attr(fail);
suspend_attr(failed_freeze);
suspend_attr(failed_prepare);
suspend_attr(failed_suspend);
suspend_attr(failed_suspend_late);
suspend_attr(failed_suspend_noirq);
suspend_attr(failed_resume);
suspend_attr(failed_resume_early);
suspend_attr(failed_resume_noirq);
suspend_attr(success, "%d\n");
suspend_attr(fail, "%d\n");
suspend_attr(failed_freeze, "%d\n");
suspend_attr(failed_prepare, "%d\n");
suspend_attr(failed_suspend, "%d\n");
suspend_attr(failed_suspend_late, "%d\n");
suspend_attr(failed_suspend_noirq, "%d\n");
suspend_attr(failed_resume, "%d\n");
suspend_attr(failed_resume_early, "%d\n");
suspend_attr(failed_resume_noirq, "%d\n");
suspend_attr(last_hw_sleep, "%llu\n");
suspend_attr(total_hw_sleep, "%llu\n");
suspend_attr(max_hw_sleep, "%llu\n");
static ssize_t last_failed_dev_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
@ -391,12 +408,30 @@ static struct attribute *suspend_attrs[] = {
&last_failed_dev.attr,
&last_failed_errno.attr,
&last_failed_step.attr,
&last_hw_sleep.attr,
&total_hw_sleep.attr,
&max_hw_sleep.attr,
NULL,
};
static umode_t suspend_attr_is_visible(struct kobject *kobj, struct attribute *attr, int idx)
{
if (attr != &last_hw_sleep.attr &&
attr != &total_hw_sleep.attr &&
attr != &max_hw_sleep.attr)
return 0444;
#ifdef CONFIG_ACPI
if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
return 0444;
#endif
return 0;
}
static const struct attribute_group suspend_attr_group = {
.name = "suspend_stats",
.attrs = suspend_attrs,
.is_visible = suspend_attr_is_visible,
};
#ifdef CONFIG_DEBUG_FS