[PATCH 3/6] cpufreq: governor: New data type for management part of dbs_data

Rafael J. Wysocki
2016-03-02T02:08:31Z

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

In addition to fields representing governor tunables, struct dbs_data
contains some fields needed for the management of objects of that
type. As it turns out, that part of struct dbs_data may be shared
with (future) governors that won't use the common code used by
"ondemand" and "conservative", so move it to a separate struct type
and modify the code using struct dbs_data to follow.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpufreq/cpufreq_conservative.c | 15 +++--
drivers/cpufreq/cpufreq_governor.c | 90 ++++++++++++++++++++-------------
drivers/cpufreq/cpufreq_governor.h | 36 +++++++------
drivers/cpufreq/cpufreq_ondemand.c | 19 ++++--
4 files changed, 97 insertions(+), 63 deletions(-)

Index: linux-pm/drivers/cpufreq/cpufreq_governor.h
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_governor.h
+++ linux-pm/drivers/cpufreq/cpufreq_governor.h
@@ -41,6 +41,13 @@
/* Ondemand Sampling types */
enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};

+struct gov_tunables {
+ struct kobject kobj;
+ struct list_head policy_list;
+ struct mutex update_lock;
+ int usage_count;
+};
+
/*
* Abbreviations:
* dbs: used as a shortform for demand based switching It helps to keep variable
@@ -52,7 +59,7 @@ enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};

/* Governor demand based switching data (per-policy or global). */
struct dbs_data {
- int usage_count;
+ struct gov_tunables gt;
void *tuners;
unsigned int min_sampling_rate;
unsigned int ignore_nice_load;
@@ -60,37 +67,34 @@ struct dbs_data {
unsigned int sampling_down_factor;
unsigned int up_threshold;
unsigned int io_is_busy;
-
- struct kobject kobj;
- struct list_head policy_dbs_list;
- /*
- * Protect concurrent updates to governor tunables from sysfs,
- * policy_dbs_list and usage_count.
- */
- struct mutex mutex;
};

+static inline struct dbs_data *to_dbs_data(struct gov_tunables *gt)
+{
+ return container_of(gt, struct dbs_data, gt);
+}
+
/* Governor's specific attributes */
-struct dbs_data;
struct governor_attr {
struct attribute attr;
- ssize_t (*show)(struct dbs_data *dbs_data, char *buf);
- ssize_t (*store)(struct dbs_data *dbs_data, const char *buf,
- size_t count);
+ ssize_t (*show)(struct gov_tunables *gt, char *buf);
+ ssize_t (*store)(struct gov_tunables *gt, const char *buf, size_t count);
};

#define gov_show_one(_gov, file_name) \
static ssize_t show_##file_name \
-(struct dbs_data *dbs_data, char *buf) \
+(struct gov_tunables *gt, char *buf) \
{ \
+ struct dbs_data *dbs_data = to_dbs_data(gt); \
struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \
return sprintf(buf, "%u\n", tuners->file_name); \
}

#define gov_show_one_common(file_name) \
static ssize_t show_##file_name \
-(struct dbs_data *dbs_data, char *buf) \
+(struct gov_tunables *gt, char *buf) \
{ \
+ struct dbs_data *dbs_data = to_dbs_data(gt); \
return sprintf(buf, "%u\n", dbs_data->file_name); \
}

@@ -184,7 +188,7 @@ void od_register_powersave_bias_handler(
(struct cpufreq_policy *, unsigned int, unsigned int),
unsigned int powersave_bias);
void od_unregister_powersave_bias_handler(void);
-ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf,
+ssize_t store_sampling_rate(struct gov_tunables *gt, const char *buf,
size_t count);
void gov_update_cpu_data(struct dbs_data *dbs_data);
#endif /* _CPUFREQ_GOVERNOR_H */
Index: linux-pm/drivers/cpufreq/cpufreq_governor.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_governor.c
+++ linux-pm/drivers/cpufreq/cpufreq_governor.c
@@ -42,9 +42,10 @@ static DEFINE_MUTEX(gov_dbs_data_mutex);
* This must be called with dbs_data->mutex held, otherwise traversing
* policy_dbs_list isn't safe.
*/
-ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf,
+ssize_t store_sampling_rate(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
struct policy_dbs_info *policy_dbs;
unsigned int rate;
int ret;
@@ -58,7 +59,7 @@ ssize_t store_sampling_rate(struct dbs_d
* We are operating under dbs_data->mutex and so the list and its
* entries can't be freed concurrently.
*/
- list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) {
+ list_for_each_entry(policy_dbs, &gt->policy_list, list) {
mutex_lock(&policy_dbs->timer_mutex);
/*
* On 32-bit architectures this may race with the
@@ -95,7 +96,7 @@ void gov_update_cpu_data(struct dbs_data
{
struct policy_dbs_info *policy_dbs;

- list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) {
+ list_for_each_entry(policy_dbs, &dbs_data->gt.policy_list, list) {
unsigned int j;

for_each_cpu(j, policy_dbs->policy->cpus) {
@@ -110,9 +111,9 @@ void gov_update_cpu_data(struct dbs_data
}
EXPORT_SYMBOL_GPL(gov_update_cpu_data);

-static inline struct dbs_data *to_dbs_data(struct kobject *kobj)
+static inline struct gov_tunables *to_gov_tunables(struct kobject *kobj)
{
- return container_of(kobj, struct dbs_data, kobj);
+ return container_of(kobj, struct gov_tunables, kobj);
}

static inline struct governor_attr *to_gov_attr(struct attribute *attr)
@@ -123,25 +124,24 @@ static inline struct governor_attr *to_g
static ssize_t governor_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
- struct dbs_data *dbs_data = to_dbs_data(kobj);
struct governor_attr *gattr = to_gov_attr(attr);

- return gattr->show(dbs_data, buf);
+ return gattr->show(to_gov_tunables(kobj), buf);
}

static ssize_t governor_store(struct kobject *kobj, struct attribute *attr,
const char *buf, size_t count)
{
- struct dbs_data *dbs_data = to_dbs_data(kobj);
+ struct gov_tunables *gt = to_gov_tunables(kobj);
struct governor_attr *gattr = to_gov_attr(attr);
int ret = -EBUSY;

- mutex_lock(&dbs_data->mutex);
+ mutex_lock(&gt->update_lock);

- if (dbs_data->usage_count)
- ret = gattr->store(dbs_data, buf, count);
+ if (gt->usage_count)
+ ret = gattr->store(gt, buf, count);

- mutex_unlock(&dbs_data->mutex);
+ mutex_unlock(&gt->update_lock);

return ret;
}
@@ -424,6 +424,41 @@ static void free_policy_dbs_info(struct
gov->free(policy_dbs);
}

+static void gov_tunables_init(struct gov_tunables *gt,
+ struct list_head *list_node)
+{
+ INIT_LIST_HEAD(&gt->policy_list);
+ mutex_init(&gt->update_lock);
+ gt->usage_count = 1;
+ list_add(list_node, &gt->policy_list);
+}
+
+static void gov_tunables_get(struct gov_tunables *gt,
+ struct list_head *list_node)
+{
+ mutex_lock(&gt->update_lock);
+ gt->usage_count++;
+ list_add(list_node, &gt->policy_list);
+ mutex_unlock(&gt->update_lock);
+}
+
+static unsigned int gov_tunables_put(struct gov_tunables *gt,
+ struct list_head *list_node)
+{
+ unsigned int count;
+
+ mutex_lock(&gt->update_lock);
+ list_del(list_node);
+ count = --gt->usage_count;
+ mutex_unlock(&gt->update_lock);
+ if (count)
+ return count;
+
+ kobject_put(&gt->kobj);
+ mutex_destroy(&gt->update_lock);
+ return 0;
+}
+
static int cpufreq_governor_init(struct cpufreq_policy *policy)
{
struct dbs_governor *gov = dbs_governor_of(policy);
@@ -452,10 +487,7 @@ static int cpufreq_governor_init(struct
policy_dbs->dbs_data = dbs_data;
policy->governor_data = policy_dbs;

- mutex_lock(&dbs_data->mutex);
- dbs_data->usage_count++;
- list_add(&policy_dbs->list, &dbs_data->policy_dbs_list);
- mutex_unlock(&dbs_data->mutex);
+ gov_tunables_get(&dbs_data->gt, &policy_dbs->list);
goto out;
}

@@ -465,8 +497,7 @@ static int cpufreq_governor_init(struct
goto free_policy_dbs_info;
}

- INIT_LIST_HEAD(&dbs_data->policy_dbs_list);
- mutex_init(&dbs_data->mutex);
+ gov_tunables_init(&dbs_data->gt, &policy_dbs->list);

ret = gov->init(dbs_data, !policy->governor->initialized);
if (ret)
@@ -486,14 +517,11 @@ static int cpufreq_governor_init(struct
if (!have_governor_per_policy())
gov->gdbs_data = dbs_data;

- policy->governor_data = policy_dbs;
-
policy_dbs->dbs_data = dbs_data;
- dbs_data->usage_count = 1;
- list_add(&policy_dbs->list, &dbs_data->policy_dbs_list);
+ policy->governor_data = policy_dbs;

gov->kobj_type.sysfs_ops = &governor_sysfs_ops;
- ret = kobject_init_and_add(&dbs_data->kobj, &gov->kobj_type,
+ ret = kobject_init_and_add(&dbs_data->gt.kobj, &gov->kobj_type,
get_governor_parent_kobj(policy),
"%s", gov->gov.name);
if (!ret)
@@ -522,29 +550,21 @@ static int cpufreq_governor_exit(struct
struct dbs_governor *gov = dbs_governor_of(policy);
struct policy_dbs_info *policy_dbs = policy->governor_data;
struct dbs_data *dbs_data = policy_dbs->dbs_data;
- int count;
+ unsigned int count;

/* Protect gov->gdbs_data against concurrent updates. */
mutex_lock(&gov_dbs_data_mutex);

- mutex_lock(&dbs_data->mutex);
- list_del(&policy_dbs->list);
- count = --dbs_data->usage_count;
- mutex_unlock(&dbs_data->mutex);
+ count = gov_tunables_put(&dbs_data->gt, &policy_dbs->list);

- if (!count) {
- kobject_put(&dbs_data->kobj);
-
- policy->governor_data = NULL;
+ policy->governor_data = NULL;

+ if (!count) {
if (!have_governor_per_policy())
gov->gdbs_data = NULL;

gov->exit(dbs_data, policy->governor->initialized == 1);
- mutex_destroy(&dbs_data->mutex);
kfree(dbs_data);
- } else {
- policy->governor_data = NULL;
}

free_policy_dbs_info(policy_dbs, gov);
Index: linux-pm/drivers/cpufreq/cpufreq_ondemand.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_ondemand.c
+++ linux-pm/drivers/cpufreq/cpufreq_ondemand.c
@@ -207,9 +207,10 @@ static unsigned int od_dbs_timer(struct
/************************** sysfs interface ************************/
static struct dbs_governor od_dbs_gov;

-static ssize_t store_io_is_busy(struct dbs_data *dbs_data, const char *buf,
+static ssize_t store_io_is_busy(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
unsigned int input;
int ret;

@@ -224,9 +225,10 @@ static ssize_t store_io_is_busy(struct d
return count;
}

-static ssize_t store_up_threshold(struct dbs_data *dbs_data, const char *buf,
+static ssize_t store_up_threshold(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
unsigned int input;
int ret;
ret = sscanf(buf, "%u", &input);
@@ -240,9 +242,10 @@ static ssize_t store_up_threshold(struct
return count;
}

-static ssize_t store_sampling_down_factor(struct dbs_data *dbs_data,
+static ssize_t store_sampling_down_factor(struct gov_tunables *gt,
const char *buf, size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
struct policy_dbs_info *policy_dbs;
unsigned int input;
int ret;
@@ -254,7 +257,7 @@ static ssize_t store_sampling_down_facto
dbs_data->sampling_down_factor = input;

/* Reset down sampling multiplier in case it was active */
- list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) {
+ list_for_each_entry(policy_dbs, &gt->policy_list, list) {
/*
* Doing this without locking might lead to using different
* rate_mult values in od_update() and od_dbs_timer().
@@ -267,9 +270,10 @@ static ssize_t store_sampling_down_facto
return count;
}

-static ssize_t store_ignore_nice_load(struct dbs_data *dbs_data,
+static ssize_t store_ignore_nice_load(struct gov_tunables *gt,
const char *buf, size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
unsigned int input;
int ret;

@@ -291,9 +295,10 @@ static ssize_t store_ignore_nice_load(st
return count;
}

-static ssize_t store_powersave_bias(struct dbs_data *dbs_data, const char *buf,
+static ssize_t store_powersave_bias(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
struct od_dbs_tuners *od_tuners = dbs_data->tuners;
struct policy_dbs_info *policy_dbs;
unsigned int input;
@@ -308,7 +313,7 @@ static ssize_t store_powersave_bias(stru

od_tuners->powersave_bias = input;

- list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list)
+ list_for_each_entry(policy_dbs, &gt->policy_list, list)
ondemand_powersave_bias_init(policy_dbs->policy);

return count;
Index: linux-pm/drivers/cpufreq/cpufreq_conservative.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq_conservative.c
+++ linux-pm/drivers/cpufreq/cpufreq_conservative.c
@@ -129,9 +129,10 @@ static struct notifier_block cs_cpufreq_
/************************** sysfs interface ************************/
static struct dbs_governor cs_dbs_gov;

-static ssize_t store_sampling_down_factor(struct dbs_data *dbs_data,
+static ssize_t store_sampling_down_factor(struct gov_tunables *gt,
const char *buf, size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
unsigned int input;
int ret;
ret = sscanf(buf, "%u", &input);
@@ -143,9 +144,10 @@ static ssize_t store_sampling_down_facto
return count;
}

-static ssize_t store_up_threshold(struct dbs_data *dbs_data, const char *buf,
+static ssize_t store_up_threshold(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
unsigned int input;
int ret;
@@ -158,9 +160,10 @@ static ssize_t store_up_threshold(struct
return count;
}

-static ssize_t store_down_threshold(struct dbs_data *dbs_data, const char *buf,
+static ssize_t store_down_threshold(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
unsigned int input;
int ret;
@@ -175,9 +178,10 @@ static ssize_t store_down_threshold(stru
return count;
}

-static ssize_t store_ignore_nice_load(struct dbs_data *dbs_data,
+static ssize_t store_ignore_nice_load(struct gov_tunables *gt,
const char *buf, size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
unsigned int input;
int ret;

@@ -199,9 +203,10 @@ static ssize_t store_ignore_nice_load(st
return count;
}

-static ssize_t store_freq_step(struct dbs_data *dbs_data, const char *buf,
+static ssize_t store_freq_step(struct gov_tunables *gt, const char *buf,
size_t count)
{
+ struct dbs_data *dbs_data = to_dbs_data(gt);
struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
unsigned int input;
int ret;