return cpumask_empty(policy->cpus);
}
-static bool suitable_policy(struct cpufreq_policy *policy, bool active)
-{
- return active == !policy_is_inactive(policy);
-}
-
-/* Finds Next Acive/Inactive policy */
-static struct cpufreq_policy *next_policy(struct cpufreq_policy *policy,
- bool active)
-{
- do {
- policy = list_next_entry(policy, policy_list);
-
- /* No more policies in the list */
- if (&policy->policy_list == &cpufreq_policy_list)
- return NULL;
- } while (!suitable_policy(policy, active));
-
- return policy;
-}
-
-static struct cpufreq_policy *first_policy(bool active)
-{
- struct cpufreq_policy *policy;
-
- /* No policies in the list */
- if (list_empty(&cpufreq_policy_list))
- return NULL;
-
- policy = list_first_entry(&cpufreq_policy_list, typeof(*policy),
- policy_list);
-
- if (!suitable_policy(policy, active))
- policy = next_policy(policy, active);
-
- return policy;
-}
-
/* Macros to iterate over CPU policies */
-#define for_each_suitable_policy(__policy, __active) \
- for (__policy = first_policy(__active); \
- __policy; \
- __policy = next_policy(__policy, __active))
+#define for_each_suitable_policy(__policy, __active) \
+ list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \
+ if ((__active) == !policy_is_inactive(__policy))
#define for_each_active_policy(__policy) \
for_each_suitable_policy(__policy, true)
static struct cpufreq_driver *cpufreq_driver;
static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
static DEFINE_RWLOCK(cpufreq_driver_lock);
-DEFINE_MUTEX(cpufreq_governor_lock);
/* Flag to suspend/resume CPUFreq governors */
static bool cpufreq_suspended;
}
/* internal prototypes */
-static int __cpufreq_governor(struct cpufreq_policy *policy,
- unsigned int event);
+static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
-static void handle_update(struct work_struct *work);
/**
* Two notifier lists: the "policy" list is involved in the
ssize_t ret;
down_read(&policy->rwsem);
-
- if (fattr->show)
- ret = fattr->show(policy, buf);
- else
- ret = -EIO;
-
+ ret = fattr->show(policy, buf);
up_read(&policy->rwsem);
return ret;
get_online_cpus();
- if (!cpu_online(policy->cpu))
- goto unlock;
-
- down_write(&policy->rwsem);
-
- if (fattr->store)
+ if (cpu_online(policy->cpu)) {
+ down_write(&policy->rwsem);
ret = fattr->store(policy, buf, count);
- else
- ret = -EIO;
+ up_write(&policy->rwsem);
+ }
- up_write(&policy->rwsem);
-unlock:
put_online_cpus();
return ret;
return cpufreq_add_dev_symlink(policy);
}
+__weak struct cpufreq_governor *cpufreq_default_governor(void)
+{
+ return NULL;
+}
+
static int cpufreq_init_policy(struct cpufreq_policy *policy)
{
struct cpufreq_governor *gov = NULL;
/* Update governor of new_policy to the governor used before hotplug */
gov = find_governor(policy->last_governor);
- if (gov)
+ if (gov) {
pr_debug("Restoring governor %s for cpu %d\n",
policy->governor->name, policy->cpu);
- else
- gov = CPUFREQ_DEFAULT_GOVERNOR;
+ } else {
+ gov = cpufreq_default_governor();
+ if (!gov)
+ return -ENODATA;
+ }
new_policy.governor = gov;
if (cpumask_test_cpu(cpu, policy->cpus))
return 0;
+ down_write(&policy->rwsem);
if (has_target()) {
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
if (ret) {
pr_err("%s: Failed to stop governor\n", __func__);
- return ret;
+ goto unlock;
}
}
- down_write(&policy->rwsem);
cpumask_set_cpu(cpu, policy->cpus);
- up_write(&policy->rwsem);
if (has_target()) {
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_START);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
if (!ret)
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
- if (ret) {
+ if (ret)
pr_err("%s: Failed to start governor\n", __func__);
- return ret;
- }
}
- return 0;
+unlock:
+ up_write(&policy->rwsem);
+ return ret;
+}
+
+static void handle_update(struct work_struct *work)
+{
+ struct cpufreq_policy *policy =
+ container_of(work, struct cpufreq_policy, update);
+ unsigned int cpu = policy->cpu;
+ pr_debug("handle_update for cpu %u called\n", cpu);
+ cpufreq_update_policy(cpu);
}
static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
{
struct device *dev = get_cpu_device(cpu);
struct cpufreq_policy *policy;
+ int ret;
if (WARN_ON(!dev))
return NULL;
if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
goto err_free_rcpumask;
- kobject_init(&policy->kobj, &ktype_cpufreq);
+ ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
+ cpufreq_global_kobject, "policy%u", cpu);
+ if (ret) {
+ pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret);
+ goto err_free_real_cpus;
+ }
+
INIT_LIST_HEAD(&policy->policy_list);
init_rwsem(&policy->rwsem);
spin_lock_init(&policy->transition_lock);
policy->cpu = cpu;
return policy;
+err_free_real_cpus:
+ free_cpumask_var(policy->real_cpus);
err_free_rcpumask:
free_cpumask_var(policy->related_cpus);
err_free_cpumask:
cpumask_copy(policy->related_cpus, policy->cpus);
/* Remember CPUs present at the policy creation time. */
cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask);
-
- /* Name and add the kobject */
- ret = kobject_add(&policy->kobj, cpufreq_global_kobject,
- "policy%u",
- cpumask_first(policy->related_cpus));
- if (ret) {
- pr_err("%s: failed to add policy->kobj: %d\n", __func__,
- ret);
- goto out_exit_policy;
- }
}
/*
return ret;
}
-static void cpufreq_offline_prepare(unsigned int cpu)
+static void cpufreq_offline(unsigned int cpu)
{
struct cpufreq_policy *policy;
+ int ret;
pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
return;
}
+ down_write(&policy->rwsem);
if (has_target()) {
- int ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
if (ret)
pr_err("%s: Failed to stop governor\n", __func__);
}
- down_write(&policy->rwsem);
cpumask_clear_cpu(cpu, policy->cpus);
if (policy_is_inactive(policy)) {
/* Nominate new CPU */
policy->cpu = cpumask_any(policy->cpus);
}
- up_write(&policy->rwsem);
/* Start governor again for active policy */
if (!policy_is_inactive(policy)) {
if (has_target()) {
- int ret = __cpufreq_governor(policy, CPUFREQ_GOV_START);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
if (!ret)
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
if (ret)
pr_err("%s: Failed to start governor\n", __func__);
}
- } else if (cpufreq_driver->stop_cpu) {
- cpufreq_driver->stop_cpu(policy);
- }
-}
-static void cpufreq_offline_finish(unsigned int cpu)
-{
- struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
-
- if (!policy) {
- pr_debug("%s: No cpu_data found\n", __func__);
- return;
+ goto unlock;
}
- /* Only proceed for inactive policies */
- if (!policy_is_inactive(policy))
- return;
+ if (cpufreq_driver->stop_cpu)
+ cpufreq_driver->stop_cpu(policy);
/* If cpu is last user of policy, free policy */
if (has_target()) {
- int ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
if (ret)
pr_err("%s: Failed to exit governor\n", __func__);
}
cpufreq_driver->exit(policy);
policy->freq_table = NULL;
}
+
+unlock:
+ up_write(&policy->rwsem);
}
/**
if (!policy)
return;
- if (cpu_online(cpu)) {
- cpufreq_offline_prepare(cpu);
- cpufreq_offline_finish(cpu);
- }
+ if (cpu_online(cpu))
+ cpufreq_offline(cpu);
cpumask_clear_cpu(cpu, policy->real_cpus);
remove_cpu_dev_symlink(policy, cpu);
cpufreq_policy_free(policy, true);
}
-static void handle_update(struct work_struct *work)
-{
- struct cpufreq_policy *policy =
- container_of(work, struct cpufreq_policy, update);
- unsigned int cpu = policy->cpu;
- pr_debug("handle_update for cpu %u called\n", cpu);
- cpufreq_update_policy(cpu);
-}
-
/**
* cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're
* in deep trouble.
{
struct cpufreq_policy *policy;
unsigned int ret_freq = 0;
+ unsigned long flags;
- if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get)
- return cpufreq_driver->get(cpu);
+ read_lock_irqsave(&cpufreq_driver_lock, flags);
+
+ if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) {
+ ret_freq = cpufreq_driver->get(cpu);
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ return ret_freq;
+ }
+
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);
policy = cpufreq_cpu_get(cpu);
if (policy) {
void cpufreq_suspend(void)
{
struct cpufreq_policy *policy;
+ int ret;
if (!cpufreq_driver)
return;
pr_debug("%s: Suspending Governors\n", __func__);
for_each_active_policy(policy) {
- if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP))
+ down_write(&policy->rwsem);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+ up_write(&policy->rwsem);
+
+ if (ret)
pr_err("%s: Failed to stop governor for policy: %p\n",
__func__, policy);
else if (cpufreq_driver->suspend
void cpufreq_resume(void)
{
struct cpufreq_policy *policy;
+ int ret;
if (!cpufreq_driver)
return;
pr_debug("%s: Resuming Governors\n", __func__);
for_each_active_policy(policy) {
- if (cpufreq_driver->resume && cpufreq_driver->resume(policy))
+ if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) {
pr_err("%s: Failed to resume driver: %p\n", __func__,
policy);
- else if (__cpufreq_governor(policy, CPUFREQ_GOV_START)
- || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS))
- pr_err("%s: Failed to start governor for policy: %p\n",
- __func__, policy);
+ } else {
+ down_write(&policy->rwsem);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
+ if (!ret)
+ cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+ up_write(&policy->rwsem);
+
+ if (ret)
+ pr_err("%s: Failed to start governor for policy: %p\n",
+ __func__, policy);
+ }
}
/*
unsigned int relation)
{
unsigned int old_target_freq = target_freq;
- int retval = -EINVAL;
+ struct cpufreq_frequency_table *freq_table;
+ int index, retval;
if (cpufreq_disabled())
return -ENODEV;
policy->restore_freq = policy->cur;
if (cpufreq_driver->target)
- retval = cpufreq_driver->target(policy, target_freq, relation);
- else if (cpufreq_driver->target_index) {
- struct cpufreq_frequency_table *freq_table;
- int index;
+ return cpufreq_driver->target(policy, target_freq, relation);
- freq_table = cpufreq_frequency_get_table(policy->cpu);
- if (unlikely(!freq_table)) {
- pr_err("%s: Unable to find freq_table\n", __func__);
- goto out;
- }
-
- retval = cpufreq_frequency_table_target(policy, freq_table,
- target_freq, relation, &index);
- if (unlikely(retval)) {
- pr_err("%s: Unable to find matching freq\n", __func__);
- goto out;
- }
+ if (!cpufreq_driver->target_index)
+ return -EINVAL;
- if (freq_table[index].frequency == policy->cur) {
- retval = 0;
- goto out;
- }
+ freq_table = cpufreq_frequency_get_table(policy->cpu);
+ if (unlikely(!freq_table)) {
+ pr_err("%s: Unable to find freq_table\n", __func__);
+ return -EINVAL;
+ }
- retval = __target_index(policy, freq_table, index);
+ retval = cpufreq_frequency_table_target(policy, freq_table, target_freq,
+ relation, &index);
+ if (unlikely(retval)) {
+ pr_err("%s: Unable to find matching freq\n", __func__);
+ return retval;
}
-out:
- return retval;
+ if (freq_table[index].frequency == policy->cur)
+ return 0;
+
+ return __target_index(policy, freq_table, index);
}
EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
-static int __cpufreq_governor(struct cpufreq_policy *policy,
- unsigned int event)
+__weak struct cpufreq_governor *cpufreq_fallback_governor(void)
{
- int ret;
+ return NULL;
+}
- /* Only must be defined when default governor is known to have latency
- restrictions, like e.g. conservative or ondemand.
- That this is the case is already ensured in Kconfig
- */
-#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
- struct cpufreq_governor *gov = &cpufreq_gov_performance;
-#else
- struct cpufreq_governor *gov = NULL;
-#endif
+static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
+{
+ int ret;
/* Don't start any governor operations if we are entering suspend */
if (cpufreq_suspended)
if (policy->governor->max_transition_latency &&
policy->cpuinfo.transition_latency >
policy->governor->max_transition_latency) {
- if (!gov)
- return -EINVAL;
- else {
+ struct cpufreq_governor *gov = cpufreq_fallback_governor();
+
+ if (gov) {
pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n",
policy->governor->name, gov->name);
policy->governor = gov;
+ } else {
+ return -EINVAL;
}
}
pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event);
- mutex_lock(&cpufreq_governor_lock);
- if ((policy->governor_enabled && event == CPUFREQ_GOV_START)
- || (!policy->governor_enabled
- && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) {
- mutex_unlock(&cpufreq_governor_lock);
- return -EBUSY;
- }
-
- if (event == CPUFREQ_GOV_STOP)
- policy->governor_enabled = false;
- else if (event == CPUFREQ_GOV_START)
- policy->governor_enabled = true;
-
- mutex_unlock(&cpufreq_governor_lock);
-
ret = policy->governor->governor(policy, event);
if (!ret) {
policy->governor->initialized++;
else if (event == CPUFREQ_GOV_POLICY_EXIT)
policy->governor->initialized--;
- } else {
- /* Restore original values */
- mutex_lock(&cpufreq_governor_lock);
- if (event == CPUFREQ_GOV_STOP)
- policy->governor_enabled = true;
- else if (event == CPUFREQ_GOV_START)
- policy->governor_enabled = false;
- mutex_unlock(&cpufreq_governor_lock);
}
if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) ||
old_gov = policy->governor;
/* end old governor */
if (old_gov) {
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
if (ret) {
/* This can happen due to race with other operations */
pr_debug("%s: Failed to Stop Governor: %s (%d)\n",
return ret;
}
- up_write(&policy->rwsem);
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
- down_write(&policy->rwsem);
-
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
if (ret) {
pr_err("%s: Failed to Exit Governor: %s (%d)\n",
__func__, old_gov->name, ret);
/* start new governor */
policy->governor = new_policy->governor;
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT);
if (!ret) {
- ret = __cpufreq_governor(policy, CPUFREQ_GOV_START);
+ ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
if (!ret)
goto out;
- up_write(&policy->rwsem);
- __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
- down_write(&policy->rwsem);
+ cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
}
/* new governor failed, so re-start old one */
pr_debug("starting governor %s failed\n", policy->governor->name);
if (old_gov) {
policy->governor = old_gov;
- if (__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT))
+ if (cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT))
policy->governor = NULL;
else
- __cpufreq_governor(policy, CPUFREQ_GOV_START);
+ cpufreq_governor(policy, CPUFREQ_GOV_START);
}
return ret;
out:
pr_debug("governor: change or update limits\n");
- return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+ return cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
}
/**
break;
case CPU_DOWN_PREPARE:
- cpufreq_offline_prepare(cpu);
- break;
-
- case CPU_POST_DEAD:
- cpufreq_offline_finish(cpu);
+ cpufreq_offline(cpu);
break;
case CPU_DOWN_FAILED:
__func__);
break;
}
+
+ down_write(&policy->rwsem);
policy->user_policy.max = policy->max;
- __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+ cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+ up_write(&policy->rwsem);
}
}
* submitted by the CPU Frequency driver.
*
* Registers a CPU Frequency driver to this core code. This code
- * returns zero on success, -EBUSY when another driver got here first
+ * returns zero on success, -EEXIST when another driver got here first
* (and isn't unregistered in the meantime).
*
*/
projects / cascardo / linux.git / blobdiff