cpufreq: move call to __find_governor() to cpufreq_init_policy()

We call __find_governor() during the addition of the first CPU of
each policy from __cpufreq_add_dev() to find the last governor used
for this CPU before it was hot-removed.

After that we call cpufreq_parse_governor() in cpufreq_init_policy(),
either with this governor, or with the default governor. Right after
that policy->governor is set to NULL.

While that code is not functionally problematic, the structure of it
is suboptimal, because some of the code required in cpufreq_init_policy()
is being executed by its caller, __cpufreq_add_dev(). So, it would make
more sense to get all of it together in a single place to make code more
readable.

Accordingly, move the code needed for policy initialization to
cpufreq_init_policy() and initialize policy->governor to NULL at the
beginning.

In order to clean up the code a bit more, some of the #ifdefs for
CONFIG_HOTPLUG_CPU are dropped too.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
viresh kumar 2014-03-04 11:43:59 +08:00 committed by Rafael J. Wysocki
parent 3b4aff0472
commit 6e2c89d16d

View File

@ -42,10 +42,8 @@ static DEFINE_RWLOCK(cpufreq_driver_lock);
DEFINE_MUTEX(cpufreq_governor_lock);
static LIST_HEAD(cpufreq_policy_list);
#ifdef CONFIG_HOTPLUG_CPU
/* This one keeps track of the previously set governor of a removed CPU */
static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor);
#endif
static inline bool has_target(void)
{
@ -879,18 +877,25 @@ err_out_kobj_put:
static void cpufreq_init_policy(struct cpufreq_policy *policy)
{
struct cpufreq_governor *gov = NULL;
struct cpufreq_policy new_policy;
int ret = 0;
memcpy(&new_policy, policy, sizeof(*policy));
/* Update governor of new_policy to the governor used before hotplug */
gov = __find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu));
if (gov)
pr_debug("Restoring governor %s for cpu %d\n",
policy->governor->name, policy->cpu);
else
gov = CPUFREQ_DEFAULT_GOVERNOR;
new_policy.governor = gov;
/* Use the default policy if its valid. */
if (cpufreq_driver->setpolicy)
cpufreq_parse_governor(policy->governor->name,
&new_policy.policy, NULL);
/* assure that the starting sequence is run in cpufreq_set_policy */
policy->governor = NULL;
cpufreq_parse_governor(gov->name, &new_policy.policy, NULL);
/* set default policy */
ret = cpufreq_set_policy(policy, &new_policy);
@ -949,6 +954,8 @@ static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu)
read_unlock_irqrestore(&cpufreq_driver_lock, flags);
policy->governor = NULL;
return policy;
}
@ -1036,7 +1043,6 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
unsigned long flags;
#ifdef CONFIG_HOTPLUG_CPU
struct cpufreq_policy *tpolicy;
struct cpufreq_governor *gov;
#endif
if (cpu_is_offline(cpu))
@ -1094,7 +1100,6 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
else
policy->cpu = cpu;
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
cpumask_copy(policy->cpus, cpumask_of(cpu));
init_completion(&policy->kobj_unregister);
@ -1180,15 +1185,6 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_START, policy);
#ifdef CONFIG_HOTPLUG_CPU
gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu));
if (gov) {
policy->governor = gov;
pr_debug("Restoring governor %s for cpu %d\n",
policy->governor->name, cpu);
}
#endif
if (!frozen) {
ret = cpufreq_add_dev_interface(policy, dev);
if (ret)
@ -1314,11 +1310,9 @@ static int __cpufreq_remove_dev_prepare(struct device *dev,
}
}
#ifdef CONFIG_HOTPLUG_CPU
if (!cpufreq_driver->setpolicy)
strncpy(per_cpu(cpufreq_cpu_governor, cpu),
policy->governor->name, CPUFREQ_NAME_LEN);
#endif
down_read(&policy->rwsem);
cpus = cpumask_weight(policy->cpus);
@ -1950,9 +1944,7 @@ EXPORT_SYMBOL_GPL(cpufreq_register_governor);
void cpufreq_unregister_governor(struct cpufreq_governor *governor)
{
#ifdef CONFIG_HOTPLUG_CPU
int cpu;
#endif
if (!governor)
return;
@ -1960,14 +1952,12 @@ void cpufreq_unregister_governor(struct cpufreq_governor *governor)
if (cpufreq_disabled())
return;
#ifdef CONFIG_HOTPLUG_CPU
for_each_present_cpu(cpu) {
if (cpu_online(cpu))
continue;
if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name))
strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0");
}
#endif
mutex_lock(&cpufreq_governor_mutex);
list_del(&governor->governor_list);