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cpufreq: Extract the handover of policy cpu to a helper function

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During cpu offline, when the policy->cpu is going down, some other CPU
present in the policy->cpus mask is nominated as the new policy->cpu.
Extract this functionality from __cpufreq_remove_dev() and implement
it in a helper function. This helps in upcoming code reorganization.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Srivatsa S. Bhat 2013-07-30 04:24:36 +05:30 committed by Rafael J. Wysocki
parent e18f1682bc
commit f9ba680d23
1 changed files with 39 additions and 24 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

63
drivers/cpufreq/cpufreq.c
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@ -1129,6 +1129,38 @@ static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu)
CPUFREQ_UPDATE_POLICY_CPU, policy); CPUFREQ_UPDATE_POLICY_CPU, policy);
} }
static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *data,
unsigned int old_cpu)
{
struct device *cpu_dev;
unsigned long flags;
int ret;
/* first sibling now owns the new sysfs dir */
cpu_dev = get_cpu_device(cpumask_first(data->cpus));
sysfs_remove_link(&cpu_dev->kobj, "cpufreq");
ret = kobject_move(&data->kobj, &cpu_dev->kobj);
if (ret) {
pr_err("%s: Failed to move kobj: %d", __func__, ret);
WARN_ON(lock_policy_rwsem_write(old_cpu));
cpumask_set_cpu(old_cpu, data->cpus);
write_lock_irqsave(&cpufreq_driver_lock, flags);
per_cpu(cpufreq_cpu_data, old_cpu) = data;
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
unlock_policy_rwsem_write(old_cpu);
ret = sysfs_create_link(&cpu_dev->kobj, &data->kobj,
"cpufreq");
return -EINVAL;
}
return cpu_dev->id;
}
/** /**
* __cpufreq_remove_dev - remove a CPU device * __cpufreq_remove_dev - remove a CPU device
* *
@ -1139,12 +1171,12 @@ static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu)
static int __cpufreq_remove_dev(struct device *dev, static int __cpufreq_remove_dev(struct device *dev,
struct subsys_interface *sif) struct subsys_interface *sif)
{ {
unsigned int cpu = dev->id, ret, cpus; unsigned int cpu = dev->id, cpus;
int new_cpu;
unsigned long flags; unsigned long flags;
struct cpufreq_policy *data; struct cpufreq_policy *data;
struct kobject *kobj; struct kobject *kobj;
struct completion *cmp; struct completion *cmp;
struct device *cpu_dev;
pr_debug("%s: unregistering CPU %u\n", __func__, cpu); pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
@ -1179,32 +1211,15 @@ static int __cpufreq_remove_dev(struct device *dev,
if (cpu != data->cpu) { if (cpu != data->cpu) {
sysfs_remove_link(&dev->kobj, "cpufreq"); sysfs_remove_link(&dev->kobj, "cpufreq");
} else if (cpus > 1) { } else if (cpus > 1) {
/* first sibling now owns the new sysfs dir */
cpu_dev = get_cpu_device(cpumask_first(data->cpus));
sysfs_remove_link(&cpu_dev->kobj, "cpufreq");
ret = kobject_move(&data->kobj, &cpu_dev->kobj);
if (ret) {
pr_err("%s: Failed to move kobj: %d", __func__, ret);
new_cpu = cpufreq_nominate_new_policy_cpu(data, cpu);
if (new_cpu >= 0) {
WARN_ON(lock_policy_rwsem_write(cpu)); WARN_ON(lock_policy_rwsem_write(cpu));
cpumask_set_cpu(cpu, data->cpus); update_policy_cpu(data, new_cpu);
write_lock_irqsave(&cpufreq_driver_lock, flags);
per_cpu(cpufreq_cpu_data, cpu) = data;
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
unlock_policy_rwsem_write(cpu); unlock_policy_rwsem_write(cpu);
pr_debug("%s: policy Kobject moved to cpu: %d "
ret = sysfs_create_link(&cpu_dev->kobj, &data->kobj, "from: %d\n",__func__, new_cpu, cpu);
"cpufreq");
return -EINVAL;
} }
WARN_ON(lock_policy_rwsem_write(cpu));
update_policy_cpu(data, cpu_dev->id);
unlock_policy_rwsem_write(cpu);
pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n",
__func__, cpu_dev->id, cpu);
} }
/* If cpu is last user of policy, free policy */ /* If cpu is last user of policy, free policy */