Re: [Update][PATCH] cpufreq: Do not hold driver module references for additional policy CPUs

[Viresh Kumar]

On 2 August 2013 10:07, Viresh Kumar <viresh.ku...@linaro.org> wrote:
>> @@ -908,7 +905,8 @@ static int cpufreq_add_policy_cpu(unsign
>>         unsigned long flags;
>>
>>         policy = cpufreq_cpu_get(sibling);
>
> This can be skipped completely at this place. Caller of
> cpufreq_add_policy_cpu() has got the policy pointer with it and so
> can be passed. I haven't done it earlier as the impression was we need
> to call cpufreq_cpu_get()..

And here is the fixup to do this (attached too):

---
 drivers/cpufreq/cpufreq.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 46e70ae..47f2a6e 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -889,21 +889,17 @@ static void cpufreq_init_policy(struct
cpufreq_policy *policy)
 }

 #ifdef CONFIG_HOTPLUG_CPU
-static int cpufreq_add_policy_cpu(unsigned int cpu, unsigned int sibling,
-                                 struct device *dev, bool frozen)
+static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy,
+                                 unsigned int cpu, struct device *dev,
+                                 bool frozen)
 {
-       struct cpufreq_policy *policy;
        int ret = 0, has_target = !!cpufreq_driver->target;
        unsigned long flags;

-       policy = cpufreq_cpu_get(sibling);
-       if (WARN_ON_ONCE(!policy))
-               return -ENODATA;
-
        if (has_target)
                __cpufreq_governor(policy, CPUFREQ_GOV_STOP);

-       lock_policy_rwsem_write(sibling);
+       lock_policy_rwsem_write(policy->cpu);

        write_lock_irqsave(&cpufreq_driver_lock, flags);

@@ -912,7 +908,7 @@ static int cpufreq_add_policy_cpu(unsigned int
cpu, unsigned int sibling,
        per_cpu(cpufreq_cpu_data, cpu) = policy;
        write_unlock_irqrestore(&cpufreq_driver_lock, flags);

-       unlock_policy_rwsem_write(sibling);
+       unlock_policy_rwsem_write(policy->cpu);

        if (has_target) {
                __cpufreq_governor(policy, CPUFREQ_GOV_START);
@@ -923,7 +919,6 @@ static int cpufreq_add_policy_cpu(unsigned int
cpu, unsigned int sibling,
        if (!frozen)
                ret = sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq");

-       cpufreq_cpu_put(policy);
        return ret;
 }
 #endif
@@ -1006,8 +1001,7 @@ static int __cpufreq_add_dev(struct device *dev,
struct subsys_interface *sif,
                struct cpufreq_policy *cp = per_cpu(cpufreq_cpu_data, sibling);
                if (cp && cpumask_test_cpu(cpu, cp->related_cpus)) {
                        read_unlock_irqrestore(&cpufreq_driver_lock, flags);
-                       return cpufreq_add_policy_cpu(cpu, sibling, dev,
-                                                     frozen);
+                       return cpufreq_add_policy_cpu(cp, cpu, dev, frozen);
                }
        }
        read_unlock_irqrestore(&cpufreq_driver_lock, flags);

0001-Fix.patch
Description: Binary data