Re: [PATCH 2/2] cpufreq: Use static SRCU initializer

From: Viresh Kumar
Date: Wed May 30 2018 - 00:50:44 EST


On 25-05-18, 12:19, Sebastian Andrzej Siewior wrote:
> Use the static SRCU initializer for `cpufreq_transition_notifier_list'.
> This avoids the init_cpufreq_transition_notifier_list() initcall. Its
> only purpose is to initialize the SRCU notifier once during boot and set
> another variable which is used as an indicator whether the init was
> perfromed before cpufreq_register_notifier() was used.
>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> CC: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> ---
> drivers/cpufreq/cpufreq.c | 13 +------------
> 1 file changed, 1 insertion(+), 12 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 075d18f6ba7a..3f7b502cfb1e 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -89,16 +89,7 @@ static void cpufreq_governor_limits(struct cpufreq_policy *policy);
> * The mutex locks both lists.
> */
> static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
> -static struct srcu_notifier_head cpufreq_transition_notifier_list;
> -
> -static bool init_cpufreq_transition_notifier_list_called;
> -static int __init init_cpufreq_transition_notifier_list(void)
> -{
> - srcu_init_notifier_head(&cpufreq_transition_notifier_list);
> - init_cpufreq_transition_notifier_list_called = true;
> - return 0;
> -}
> -pure_initcall(init_cpufreq_transition_notifier_list);
> +SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list);
>
> static int off __read_mostly;
> static int cpufreq_disabled(void)
> @@ -1764,8 +1755,6 @@ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
> if (cpufreq_disabled())
> return -EINVAL;
>
> - WARN_ON(!init_cpufreq_transition_notifier_list_called);
> -
> switch (list) {
> case CPUFREQ_TRANSITION_NOTIFIER:
> mutex_lock(&cpufreq_fast_switch_lock);

Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

--
viresh