Re: [PATCH V2 01/20] cpufreq: Add doc style comment about cpufreq_cpu_{get|put}()

On 02/19/2015 03:32 AM, Viresh Kumar wrote:

This clearly states what the code inside these routines is doing and how these must be used.

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org

drivers/cpufreq/cpufreq.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 28e59a48b35f..fc51b8fbb0b0 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -207,6 +207,23 @@ struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) return per_cpu(cpufreq_cpu_data, cpu); }

+/**

• • cpufreq_cpu_get: returns policy for a cpu and marks it busy.
• • @cpu: cpu to find policy for.
• • This returns policy for 'cpu', returns NULL if it doesn't exist.
• • It also increments the kobject reference count to mark it busy and so would
• • require a corresponding call to cpufreq_cpu_put() to decrement it back.
• • If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be
• • freed as that depends on the kobj count.
• • It also takes a read-lock of 'cpufreq_rwsem' and doesn't put it back if a
• • valid policy is found. This is done to make sure the driver doesn't get
• • unregistered while the policy is being used.
• • Return: A valid policy on success, otherwise NULL on failure.
• */ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) { struct cpufreq_policy *policy = NULL;

@@ -237,6 +254,16 @@ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) } EXPORT_SYMBOL_GPL(cpufreq_cpu_get);

+/**

• • cpufreq_cpu_put: Decrements the usage count of a policy
• • @policy: policy earlier returned by cpufreq_cpu_get().
• • This decrements the kobject reference count incremented earlier by calling
• • cpufreq_cpu_get().
• • It also drops the read-lock of 'cpufreq_rwsem' taken at cpufreq_cpu_get().
• */ void cpufreq_cpu_put(struct cpufreq_policy *policy) { kobject_put(&policy->kobj);

Acked-by: Saravana Kannan skannan@codeaurora.org

-Saravana