Re: [PATCH v2 1/4] thermal: cpufreq_cooling: Use private callback ops for each cooling device

From: Viresh Kumar
Date: Mon Jun 13 2022 - 22:47:14 EST


On 13-06-22, 13:43, Lukasz Luba wrote:
> It is very unlikely that one CPU cluster would have the EM and some other
> won't have it (because EM registration failed or DT lacks needed entry).
> Although, we should avoid modifying global variable with callbacks anyway.
> Redesign this and add safety for such situation.
>
> Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
> ---
> drivers/thermal/cpufreq_cooling.c | 15 ++++++---------
> 1 file changed, 6 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/thermal/cpufreq_cooling.c b/drivers/thermal/cpufreq_cooling.c
> index b8151d95a806..ad8b86f5281b 100644
> --- a/drivers/thermal/cpufreq_cooling.c
> +++ b/drivers/thermal/cpufreq_cooling.c
> @@ -59,6 +59,7 @@ struct time_in_idle {
> * @cdev: thermal_cooling_device pointer to keep track of the
> * registered cooling device.
> * @policy: cpufreq policy.
> + * @cooling_ops: cpufreq callbacks to thermal cooling device ops
> * @idle_time: idle time stats
> * @qos_req: PM QoS contraint to apply
> *
> @@ -71,6 +72,7 @@ struct cpufreq_cooling_device {
> unsigned int max_level;
> struct em_perf_domain *em;
> struct cpufreq_policy *policy;
> + struct thermal_cooling_device_ops cooling_ops;
> #ifndef CONFIG_SMP
> struct time_in_idle *idle_time;
> #endif
> @@ -485,14 +487,6 @@ static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev,
> return ret;
> }
>
> -/* Bind cpufreq callbacks to thermal cooling device ops */
> -
> -static struct thermal_cooling_device_ops cpufreq_cooling_ops = {
> - .get_max_state = cpufreq_get_max_state,
> - .get_cur_state = cpufreq_get_cur_state,
> - .set_cur_state = cpufreq_set_cur_state,
> -};
> -
> /**
> * __cpufreq_cooling_register - helper function to create cpufreq cooling device
> * @np: a valid struct device_node to the cooling device device tree node
> @@ -554,7 +548,10 @@ __cpufreq_cooling_register(struct device_node *np,
> /* max_level is an index, not a counter */
> cpufreq_cdev->max_level = i - 1;
>
> - cooling_ops = &cpufreq_cooling_ops;
> + cooling_ops = &cpufreq_cdev->cooling_ops;
> + cooling_ops->get_max_state = cpufreq_get_max_state;
> + cooling_ops->get_cur_state = cpufreq_get_cur_state;
> + cooling_ops->set_cur_state = cpufreq_set_cur_state;
>
> #ifdef CONFIG_THERMAL_GOV_POWER_ALLOCATOR
> if (em_is_sane(cpufreq_cdev, em)) {

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

--
viresh