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authorViresh Kumar <viresh.kumar@linaro.org>2018-04-02 16:26:25 +0530
committerZhang Rui <rui.zhang@intel.com>2018-04-02 21:49:01 +0800
commit8ea229511e06f9635ecc338dcbe0db41a73623f0 (patch)
treea963ef526322117373498ff22950fffc942a5b14 /drivers/thermal
parent0c8efd610b58cb23cefdfa12015799079aef94ae (diff)
downloadlinux-8ea229511e06f9635ecc338dcbe0db41a73623f0.tar.bz2
thermal: Add cooling device's statistics in sysfs
This extends the sysfs interface for thermal cooling devices and exposes some pretty useful statistics. These statistics have proven to be quite useful specially while doing benchmarks related to the task scheduler, where we want to make sure that nothing has disrupted the test, specially the cooling device which may have put constraints on the CPUs. The information exposed here tells us to what extent the CPUs were constrained by the thermal framework. The write-only "reset" file is used to reset the statistics. The read-only "time_in_state_ms" file shows the time (in msec) spent by the device in the respective cooling states, and it prints one line per cooling state. The read-only "total_trans" file shows single positive integer value showing the total number of cooling state transitions the device has gone through since the time the cooling device is registered or the time when statistics were reset last. The read-only "trans_table" file shows a two dimensional matrix, where an entry <i,j> (row i, column j) represents the number of transitions from State_i to State_j. This is how the directory structure looks like for a single cooling device: $ ls -R /sys/class/thermal/cooling_device0/ /sys/class/thermal/cooling_device0/: cur_state max_state power stats subsystem type uevent /sys/class/thermal/cooling_device0/power: autosuspend_delay_ms runtime_active_time runtime_suspended_time control runtime_status /sys/class/thermal/cooling_device0/stats: reset time_in_state_ms total_trans trans_table This is tested on ARM 64-bit Hisilicon hikey620 board running Ubuntu and ARM 64-bit Hisilicon hikey960 board running Android. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Diffstat (limited to 'drivers/thermal')
-rw-r--r--drivers/thermal/Kconfig7
-rw-r--r--drivers/thermal/thermal_core.c3
-rw-r--r--drivers/thermal/thermal_core.h10
-rw-r--r--drivers/thermal/thermal_helpers.c5
-rw-r--r--drivers/thermal/thermal_sysfs.c225
5 files changed, 248 insertions, 2 deletions
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index b6adc54b96f1..82979880f985 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -15,6 +15,13 @@ menuconfig THERMAL
if THERMAL
+config THERMAL_STATISTICS
+ bool "Thermal state transition statistics"
+ help
+ Export thermal state transition statistics information through sysfs.
+
+ If in doubt, say N.
+
config THERMAL_EMERGENCY_POWEROFF_DELAY_MS
int "Emergency poweroff delay in milli-seconds"
depends on THERMAL
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 2b1b0ba393a4..d64325e078db 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -972,8 +972,8 @@ __thermal_cooling_device_register(struct device_node *np,
cdev->ops = ops;
cdev->updated = false;
cdev->device.class = &thermal_class;
- thermal_cooling_device_setup_sysfs(cdev);
cdev->devdata = devdata;
+ thermal_cooling_device_setup_sysfs(cdev);
dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
result = device_register(&cdev->device);
if (result) {
@@ -1106,6 +1106,7 @@ void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
ida_simple_remove(&thermal_cdev_ida, cdev->id);
device_unregister(&cdev->device);
+ thermal_cooling_device_destroy_sysfs(cdev);
}
EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
index 27e3b1df7360..5e4150261500 100644
--- a/drivers/thermal/thermal_core.h
+++ b/drivers/thermal/thermal_core.h
@@ -73,6 +73,7 @@ int thermal_build_list_of_policies(char *buf);
int thermal_zone_create_device_groups(struct thermal_zone_device *, int);
void thermal_zone_destroy_device_groups(struct thermal_zone_device *);
void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *);
+void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev);
/* used only at binding time */
ssize_t
thermal_cooling_device_trip_point_show(struct device *,
@@ -84,6 +85,15 @@ ssize_t thermal_cooling_device_weight_store(struct device *,
struct device_attribute *,
const char *, size_t);
+#ifdef CONFIG_THERMAL_STATISTICS
+void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
+ unsigned long new_state);
+#else
+static inline void
+thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
+ unsigned long new_state) {}
+#endif /* CONFIG_THERMAL_STATISTICS */
+
#ifdef CONFIG_THERMAL_GOV_STEP_WISE
int thermal_gov_step_wise_register(void);
void thermal_gov_step_wise_unregister(void);
diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c
index 8cdf75adcce1..eb03d7e099bb 100644
--- a/drivers/thermal/thermal_helpers.c
+++ b/drivers/thermal/thermal_helpers.c
@@ -187,7 +187,10 @@ void thermal_cdev_update(struct thermal_cooling_device *cdev)
if (instance->target > target)
target = instance->target;
}
- cdev->ops->set_cur_state(cdev, target);
+
+ if (!cdev->ops->set_cur_state(cdev, target))
+ thermal_cooling_device_stats_update(cdev, target);
+
cdev->updated = true;
mutex_unlock(&cdev->lock);
trace_cdev_update(cdev, target);
diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
index ba81c9080f6e..23b5e0a709b0 100644
--- a/drivers/thermal/thermal_sysfs.c
+++ b/drivers/thermal/thermal_sysfs.c
@@ -20,6 +20,7 @@
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/jiffies.h>
#include "thermal_core.h"
@@ -721,6 +722,7 @@ thermal_cooling_device_cur_state_store(struct device *dev,
result = cdev->ops->set_cur_state(cdev, state);
if (result)
return result;
+ thermal_cooling_device_stats_update(cdev, state);
return count;
}
@@ -745,14 +747,237 @@ static const struct attribute_group cooling_device_attr_group = {
static const struct attribute_group *cooling_device_attr_groups[] = {
&cooling_device_attr_group,
+ NULL, /* Space allocated for cooling_device_stats_attr_group */
NULL,
};
+#ifdef CONFIG_THERMAL_STATISTICS
+struct cooling_dev_stats {
+ spinlock_t lock;
+ unsigned int total_trans;
+ unsigned long state;
+ unsigned long max_states;
+ ktime_t last_time;
+ ktime_t *time_in_state;
+ unsigned int *trans_table;
+};
+
+static void update_time_in_state(struct cooling_dev_stats *stats)
+{
+ ktime_t now = ktime_get(), delta;
+
+ delta = ktime_sub(now, stats->last_time);
+ stats->time_in_state[stats->state] =
+ ktime_add(stats->time_in_state[stats->state], delta);
+ stats->last_time = now;
+}
+
+void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
+ unsigned long new_state)
+{
+ struct cooling_dev_stats *stats = cdev->stats;
+
+ spin_lock(&stats->lock);
+
+ if (stats->state == new_state)
+ goto unlock;
+
+ update_time_in_state(stats);
+ stats->trans_table[stats->state * stats->max_states + new_state]++;
+ stats->state = new_state;
+ stats->total_trans++;
+
+unlock:
+ spin_unlock(&stats->lock);
+}
+
+static ssize_t
+thermal_cooling_device_total_trans_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct thermal_cooling_device *cdev = to_cooling_device(dev);
+ struct cooling_dev_stats *stats = cdev->stats;
+ int ret;
+
+ spin_lock(&stats->lock);
+ ret = sprintf(buf, "%u\n", stats->total_trans);
+ spin_unlock(&stats->lock);
+
+ return ret;
+}
+
+static ssize_t
+thermal_cooling_device_time_in_state_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct thermal_cooling_device *cdev = to_cooling_device(dev);
+ struct cooling_dev_stats *stats = cdev->stats;
+ ssize_t len = 0;
+ int i;
+
+ spin_lock(&stats->lock);
+ update_time_in_state(stats);
+
+ for (i = 0; i < stats->max_states; i++) {
+ len += sprintf(buf + len, "state%u\t%llu\n", i,
+ ktime_to_ms(stats->time_in_state[i]));
+ }
+ spin_unlock(&stats->lock);
+
+ return len;
+}
+
+static ssize_t
+thermal_cooling_device_reset_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct thermal_cooling_device *cdev = to_cooling_device(dev);
+ struct cooling_dev_stats *stats = cdev->stats;
+ int i, states = stats->max_states;
+
+ spin_lock(&stats->lock);
+
+ stats->total_trans = 0;
+ stats->last_time = ktime_get();
+ memset(stats->trans_table, 0,
+ states * states * sizeof(*stats->trans_table));
+
+ for (i = 0; i < stats->max_states; i++)
+ stats->time_in_state[i] = ktime_set(0, 0);
+
+ spin_unlock(&stats->lock);
+
+ return count;
+}
+
+static ssize_t
+thermal_cooling_device_trans_table_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct thermal_cooling_device *cdev = to_cooling_device(dev);
+ struct cooling_dev_stats *stats = cdev->stats;
+ ssize_t len = 0;
+ int i, j;
+
+ len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
+ len += snprintf(buf + len, PAGE_SIZE - len, " : ");
+ for (i = 0; i < stats->max_states; i++) {
+ if (len >= PAGE_SIZE)
+ break;
+ len += snprintf(buf + len, PAGE_SIZE - len, "state%2u ", i);
+ }
+ if (len >= PAGE_SIZE)
+ return PAGE_SIZE;
+
+ len += snprintf(buf + len, PAGE_SIZE - len, "\n");
+
+ for (i = 0; i < stats->max_states; i++) {
+ if (len >= PAGE_SIZE)
+ break;
+
+ len += snprintf(buf + len, PAGE_SIZE - len, "state%2u:", i);
+
+ for (j = 0; j < stats->max_states; j++) {
+ if (len >= PAGE_SIZE)
+ break;
+ len += snprintf(buf + len, PAGE_SIZE - len, "%8u ",
+ stats->trans_table[i * stats->max_states + j]);
+ }
+ if (len >= PAGE_SIZE)
+ break;
+ len += snprintf(buf + len, PAGE_SIZE - len, "\n");
+ }
+
+ if (len >= PAGE_SIZE) {
+ pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n");
+ return -EFBIG;
+ }
+ return len;
+}
+
+static DEVICE_ATTR(total_trans, 0444, thermal_cooling_device_total_trans_show,
+ NULL);
+static DEVICE_ATTR(time_in_state_ms, 0444,
+ thermal_cooling_device_time_in_state_show, NULL);
+static DEVICE_ATTR(reset, 0200, NULL, thermal_cooling_device_reset_store);
+static DEVICE_ATTR(trans_table, 0444,
+ thermal_cooling_device_trans_table_show, NULL);
+
+static struct attribute *cooling_device_stats_attrs[] = {
+ &dev_attr_total_trans.attr,
+ &dev_attr_time_in_state_ms.attr,
+ &dev_attr_reset.attr,
+ &dev_attr_trans_table.attr,
+ NULL
+};
+
+static const struct attribute_group cooling_device_stats_attr_group = {
+ .attrs = cooling_device_stats_attrs,
+ .name = "stats"
+};
+
+static void cooling_device_stats_setup(struct thermal_cooling_device *cdev)
+{
+ struct cooling_dev_stats *stats;
+ unsigned long states;
+ int var;
+
+ if (cdev->ops->get_max_state(cdev, &states))
+ return;
+
+ states++; /* Total number of states is highest state + 1 */
+
+ var = sizeof(*stats);
+ var += sizeof(*stats->time_in_state) * states;
+ var += sizeof(*stats->trans_table) * states * states;
+
+ stats = kzalloc(var, GFP_KERNEL);
+ if (!stats)
+ return;
+
+ stats->time_in_state = (ktime_t *)(stats + 1);
+ stats->trans_table = (unsigned int *)(stats->time_in_state + states);
+ cdev->stats = stats;
+ stats->last_time = ktime_get();
+ stats->max_states = states;
+
+ spin_lock_init(&stats->lock);
+
+ /* Fill the empty slot left in cooling_device_attr_groups */
+ var = ARRAY_SIZE(cooling_device_attr_groups) - 2;
+ cooling_device_attr_groups[var] = &cooling_device_stats_attr_group;
+}
+
+static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev)
+{
+ kfree(cdev->stats);
+ cdev->stats = NULL;
+}
+
+#else
+
+static inline void
+cooling_device_stats_setup(struct thermal_cooling_device *cdev) {}
+static inline void
+cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {}
+
+#endif /* CONFIG_THERMAL_STATISTICS */
+
void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
{
+ cooling_device_stats_setup(cdev);
cdev->device.groups = cooling_device_attr_groups;
}
+void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev)
+{
+ cooling_device_stats_destroy(cdev);
+}
+
/* these helper will be used only at the time of bindig */
ssize_t
thermal_cooling_device_trip_point_show(struct device *dev,