[PATCH 4/5] cpufreq: create cpu/cpufreq/policyX directories

Viresh Kumar
2015-10-11T17:21:47Z

The cpufreq sysfs interface had been a bit inconsistent as one of the
CPUs for a policy had a real directory within its sysfs 'cpuX' directory
and all other CPUs had links to it. That also made the code a bit
complex as we need to take care of moving the sysfs directory if the CPU
containing the real directory is getting physically hot-unplugged.

Solve this by creating 'policyX' directories (per-policy) in
/sys/devices/system/cpu/cpufreq/ directory, where X is the CPU for which
the policy was first created.

This also removes the need of keeping kobj_cpu and we can remove it now.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
drivers/cpufreq/cpufreq.c | 34 ++++------------------------------
include/linux/cpufreq.h | 1 -
2 files changed, 4 insertions(+), 31 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 2cb0e3b8170e..58aabe0f2d2c 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -917,9 +917,6 @@ static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy)

/* Some related CPUs might not be present (physically hotplugged) */
for_each_cpu(j, policy->real_cpus) {
- if (j == policy->kobj_cpu)
- continue;
-
ret = add_cpu_dev_symlink(policy, j);
if (ret)
break;
@@ -933,12 +930,8 @@ static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy)
unsigned int j;

/* Some related CPUs might not be present (physically hotplugged) */
- for_each_cpu(j, policy->real_cpus) {
- if (j == policy->kobj_cpu)
- continue;
-
+ for_each_cpu(j, policy->real_cpus)
remove_cpu_dev_symlink(policy, j);
- }
}

static int cpufreq_add_dev_interface(struct cpufreq_policy *policy)
@@ -1054,8 +1047,8 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
goto err_free_rcpumask;

- ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &dev->kobj,
- "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;
@@ -1069,10 +1062,6 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
INIT_WORK(&policy->update, handle_update);

policy->cpu = cpu;
-
- /* Set this once on allocation */
- policy->kobj_cpu = cpu;
-
return policy;

err_free_real_cpus:
@@ -1424,22 +1413,7 @@ static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
return;
}

- if (cpu != policy->kobj_cpu) {
- remove_cpu_dev_symlink(policy, cpu);
- } else {
- /*
- * The CPU owning the policy object is going away. Move it to
- * another suitable CPU.
- */
- unsigned int new_cpu = cpumask_first(policy->real_cpus);
- struct device *new_dev = get_cpu_device(new_cpu);
-
- dev_dbg(dev, "%s: Moving policy object to CPU%u\n", __func__, new_cpu);
-
- sysfs_remove_link(&new_dev->kobj, "cpufreq");
- policy->kobj_cpu = new_cpu;
- WARN_ON(kobject_move(&policy->kobj, &new_dev->kobj));
- }
+ remove_cpu_dev_symlink(policy, cpu);
}

static void handle_update(struct work_struct *work)
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 9623218d996a..ef4c5b1a860f 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -65,7 +65,6 @@ struct cpufreq_policy {
unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs
should set cpufreq */
unsigned int cpu; /* cpu managing this policy, must be online */
- unsigned int kobj_cpu; /* cpu managing sysfs files, can be offline */

struct clk *clk;
struct cpufreq_cpuinfo cpuinfo;/* see above */
--
2.4.0