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Diffstat (limited to 'drivers/devfreq/devfreq.c')
-rw-r--r--drivers/devfreq/devfreq.c90
1 files changed, 59 insertions, 31 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 0ae3de76833b..6b6991f0e873 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -29,6 +29,9 @@
#include <linux/of.h>
#include "governor.h"
+#define CREATE_TRACE_POINTS
+#include <trace/events/devfreq.h>
+
static struct class *devfreq_class;
/*
@@ -228,7 +231,7 @@ static struct devfreq_governor *find_devfreq_governor(const char *name)
* if is not found. This can happen when both drivers (the governor driver
* and the driver that call devfreq_add_device) are built as modules.
* devfreq_list_lock should be held by the caller. Returns the matched
- * governor's pointer.
+ * governor's pointer or an error pointer.
*/
static struct devfreq_governor *try_then_request_governor(const char *name)
{
@@ -254,7 +257,7 @@ static struct devfreq_governor *try_then_request_governor(const char *name)
/* Restore previous state before return */
mutex_lock(&devfreq_list_lock);
if (err)
- return NULL;
+ return ERR_PTR(err);
governor = find_devfreq_governor(name);
}
@@ -394,6 +397,8 @@ static void devfreq_monitor(struct work_struct *work)
queue_delayed_work(devfreq_wq, &devfreq->work,
msecs_to_jiffies(devfreq->profile->polling_ms));
mutex_unlock(&devfreq->lock);
+
+ trace_devfreq_monitor(devfreq);
}
/**
@@ -528,7 +533,7 @@ void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay)
mutex_lock(&devfreq->lock);
if (!devfreq->stop_polling)
queue_delayed_work(devfreq_wq, &devfreq->work,
- msecs_to_jiffies(devfreq->profile->polling_ms));
+ msecs_to_jiffies(devfreq->profile->polling_ms));
}
out:
mutex_unlock(&devfreq->lock);
@@ -537,7 +542,7 @@ EXPORT_SYMBOL(devfreq_interval_update);
/**
* devfreq_notifier_call() - Notify that the device frequency requirements
- * has been changed out of devfreq framework.
+ * has been changed out of devfreq framework.
* @nb: the notifier_block (supposed to be devfreq->nb)
* @type: not used
* @devp: not used
@@ -651,7 +656,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
mutex_unlock(&devfreq->lock);
err = set_freq_table(devfreq);
if (err < 0)
- goto err_out;
+ goto err_dev;
mutex_lock(&devfreq->lock);
}
@@ -683,16 +688,27 @@ struct devfreq *devfreq_add_device(struct device *dev,
goto err_out;
}
- devfreq->trans_table =
- devm_kzalloc(&devfreq->dev,
- array3_size(sizeof(unsigned int),
- devfreq->profile->max_state,
- devfreq->profile->max_state),
- GFP_KERNEL);
+ devfreq->trans_table = devm_kzalloc(&devfreq->dev,
+ array3_size(sizeof(unsigned int),
+ devfreq->profile->max_state,
+ devfreq->profile->max_state),
+ GFP_KERNEL);
+ if (!devfreq->trans_table) {
+ mutex_unlock(&devfreq->lock);
+ err = -ENOMEM;
+ goto err_devfreq;
+ }
+
devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
- devfreq->profile->max_state,
- sizeof(unsigned long),
- GFP_KERNEL);
+ devfreq->profile->max_state,
+ sizeof(unsigned long),
+ GFP_KERNEL);
+ if (!devfreq->time_in_state) {
+ mutex_unlock(&devfreq->lock);
+ err = -ENOMEM;
+ goto err_devfreq;
+ }
+
devfreq->last_stat_updated = jiffies;
srcu_init_notifier_head(&devfreq->transition_notifier_list);
@@ -726,7 +742,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
err_init:
mutex_unlock(&devfreq_list_lock);
-
+err_devfreq:
devfreq_remove_device(devfreq);
devfreq = NULL;
err_dev:
@@ -1113,7 +1129,7 @@ static ssize_t governor_store(struct device *dev, struct device_attribute *attr,
struct devfreq *df = to_devfreq(dev);
int ret;
char str_governor[DEVFREQ_NAME_LEN + 1];
- struct devfreq_governor *governor;
+ const struct devfreq_governor *governor, *prev_governor;
ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor);
if (ret != 1)
@@ -1142,12 +1158,24 @@ static ssize_t governor_store(struct device *dev, struct device_attribute *attr,
goto out;
}
}
+ prev_governor = df->governor;
df->governor = governor;
strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN);
ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL);
- if (ret)
+ if (ret) {
dev_warn(dev, "%s: Governor %s not started(%d)\n",
__func__, df->governor->name, ret);
+ df->governor = prev_governor;
+ strncpy(df->governor_name, prev_governor->name,
+ DEVFREQ_NAME_LEN);
+ ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL);
+ if (ret) {
+ dev_err(dev,
+ "%s: reverting to Governor %s failed (%d)\n",
+ __func__, df->governor_name, ret);
+ df->governor = NULL;
+ }
+ }
out:
mutex_unlock(&devfreq_list_lock);
@@ -1172,7 +1200,7 @@ static ssize_t available_governors_show(struct device *d,
*/
if (df->governor->immutable) {
count = scnprintf(&buf[count], DEVFREQ_NAME_LEN,
- "%s ", df->governor_name);
+ "%s ", df->governor_name);
/*
* The devfreq device shows the registered governor except for
* immutable governors such as passive governor .
@@ -1485,8 +1513,8 @@ EXPORT_SYMBOL(devfreq_recommended_opp);
/**
* devfreq_register_opp_notifier() - Helper function to get devfreq notified
- * for any changes in the OPP availability
- * changes
+ * for any changes in the OPP availability
+ * changes
* @dev: The devfreq user device. (parent of devfreq)
* @devfreq: The devfreq object.
*/
@@ -1498,8 +1526,8 @@ EXPORT_SYMBOL(devfreq_register_opp_notifier);
/**
* devfreq_unregister_opp_notifier() - Helper function to stop getting devfreq
- * notified for any changes in the OPP
- * availability changes anymore.
+ * notified for any changes in the OPP
+ * availability changes anymore.
* @dev: The devfreq user device. (parent of devfreq)
* @devfreq: The devfreq object.
*
@@ -1518,8 +1546,8 @@ static void devm_devfreq_opp_release(struct device *dev, void *res)
}
/**
- * devm_ devfreq_register_opp_notifier()
- * - Resource-managed devfreq_register_opp_notifier()
+ * devm_devfreq_register_opp_notifier() - Resource-managed
+ * devfreq_register_opp_notifier()
* @dev: The devfreq user device. (parent of devfreq)
* @devfreq: The devfreq object.
*/
@@ -1547,8 +1575,8 @@ int devm_devfreq_register_opp_notifier(struct device *dev,
EXPORT_SYMBOL(devm_devfreq_register_opp_notifier);
/**
- * devm_devfreq_unregister_opp_notifier()
- * - Resource-managed devfreq_unregister_opp_notifier()
+ * devm_devfreq_unregister_opp_notifier() - Resource-managed
+ * devfreq_unregister_opp_notifier()
* @dev: The devfreq user device. (parent of devfreq)
* @devfreq: The devfreq object.
*/
@@ -1567,8 +1595,8 @@ EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier);
* @list: DEVFREQ_TRANSITION_NOTIFIER.
*/
int devfreq_register_notifier(struct devfreq *devfreq,
- struct notifier_block *nb,
- unsigned int list)
+ struct notifier_block *nb,
+ unsigned int list)
{
int ret = 0;
@@ -1674,9 +1702,9 @@ EXPORT_SYMBOL(devm_devfreq_register_notifier);
* @list: DEVFREQ_TRANSITION_NOTIFIER.
*/
void devm_devfreq_unregister_notifier(struct device *dev,
- struct devfreq *devfreq,
- struct notifier_block *nb,
- unsigned int list)
+ struct devfreq *devfreq,
+ struct notifier_block *nb,
+ unsigned int list)
{
WARN_ON(devres_release(dev, devm_devfreq_notifier_release,
devm_devfreq_dev_match, devfreq));
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-20 23:43:47 +0100