On 02/14/2014 04:30 PM, Viresh Kumar wrote:
> cpufreq_update_policy() is called from two places currently. From a workqueue
> handled queued from cpufreq_bp_resume() for boot CPU and from
> cpufreq_cpu_callback() whenever a CPU is added.
>
> The first one makes sure that boot CPU is running on the frequency present in
> policy->cpu. But we don't really need a call from cpufreq_cpu_callback(),
> because we always call cpufreq_driver->init() (which will set policy->cur
> correctly) whenever first CPU of any policy is added back. And so every policy
> structure is guaranteed to have the right frequency in policy->cur.
>
This wording is slightly inaccurate. ->init() may or may not set policy->cur
(for example, powernowk8 driver doesn't set it in the init routine)..
But we set it for sure in __cpufreq_add_dev():
1117 if (cpufreq_driver->get) {
1118 policy->cur = cpufreq_driver->get(policy->cpu);
1119 if (!policy->cur) {
1120 pr_err("%s: ->get() failed\n", __func__);
1121 goto err_get_freq;
1122 }
1123 }
> Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
The reasoning and the code looks good to me.
Reviewed-by: Srivatsa S. Bhat <srivatsa.b...@linux.vnet.ibm.com>
Regards,
Srivatsa S. Bhat
> ---
> drivers/cpufreq/cpufreq.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 383362b..b6eb4ed 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -2194,7 +2194,6 @@ static int cpufreq_cpu_callback(struct notifier_block
> *nfb,
> switch (action & ~CPU_TASKS_FROZEN) {
> case CPU_ONLINE:
> __cpufreq_add_dev(dev, NULL, frozen);
> - cpufreq_update_policy(cpu);
> break;
>
> case CPU_DOWN_PREPARE:
>
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