Re: [PATCH 1/5] thermal: Initialize thermal subsystem earlier

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 12/09/2019 00:32, Amit Kucheria wrote:
> From: Lina Iyer <ilina@codeaurora.org>
> 
> Now that the thermal framework is built-in, in order to facilitate
> thermal mitigation as early as possible in the boot cycle, move the
> thermal framework initialization to core_initcall.
> 
> However, netlink initialization happens only as part of subsys_initcall.
> At this time in the boot process, the userspace is not available yet. So
> initialize the netlink events later in fs_initcall.

Why not kill directly the netlink part, no one is using it in the kernel?


> Signed-off-by: Lina Iyer <ilina@codeaurora.org>
> [Rebased, refactored and moved to core_initcall]
> Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> ---
>  drivers/thermal/thermal_core.c | 41 ++++++++++++++++++++--------------
>  1 file changed, 24 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 6bab66e84eb5..b13e8a9298cc 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -1468,6 +1468,8 @@ static struct genl_family thermal_event_genl_family __ro_after_init = {
>  	.n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
>  };
>  
> +static bool allow_netlink_events;
> +
>  int thermal_generate_netlink_event(struct thermal_zone_device *tz,
>  				   enum events event)
>  {
> @@ -1482,6 +1484,9 @@ int thermal_generate_netlink_event(struct thermal_zone_device *tz,
>  	if (!tz)
>  		return -EINVAL;
>  
> +	if (!allow_netlink_events)
> +		return -ENODEV;
> +
>  	/* allocate memory */
>  	size = nla_total_size(sizeof(struct thermal_genl_event)) +
>  	       nla_total_size(0);
> @@ -1533,16 +1538,18 @@ EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
>  
>  static int __init genetlink_init(void)
>  {
> -	return genl_register_family(&thermal_event_genl_family);
> -}
> +	int ret;
>  
> -static void genetlink_exit(void)
> -{
> -	genl_unregister_family(&thermal_event_genl_family);
> +	ret = genl_register_family(&thermal_event_genl_family);
> +	if (!ret)
> +		allow_netlink_events = true;
> +	return ret;
>  }
> +
>  #else /* !CONFIG_NET */
>  static inline int genetlink_init(void) { return 0; }
> -static inline void genetlink_exit(void) {}
> +static inline int thermal_generate_netlink_event(struct thermal_zone_device *tz,
> +						 enum events event) { return -ENODEV; }
>  #endif /* !CONFIG_NET */
>  
>  static int thermal_pm_notify(struct notifier_block *nb,
> @@ -1591,19 +1598,15 @@ static int __init thermal_init(void)
>  	mutex_init(&poweroff_lock);
>  	result = thermal_register_governors();
>  	if (result)
> -		goto error;
> +		goto init_exit;
>  
>  	result = class_register(&thermal_class);
>  	if (result)
>  		goto unregister_governors;
>  
> -	result = genetlink_init();
> -	if (result)
> -		goto unregister_class;
> -
>  	result = of_parse_thermal_zones();
>  	if (result)
> -		goto exit_netlink;
> +		goto exit_zone_parse;
>  
>  	result = register_pm_notifier(&thermal_pm_nb);
>  	if (result)
> @@ -1612,13 +1615,11 @@ static int __init thermal_init(void)
>  
>  	return 0;
>  
> -exit_netlink:
> -	genetlink_exit();
> -unregister_class:
> +exit_zone_parse:
>  	class_unregister(&thermal_class);
>  unregister_governors:
>  	thermal_unregister_governors();
> -error:
> +init_exit:
>  	ida_destroy(&thermal_tz_ida);
>  	ida_destroy(&thermal_cdev_ida);
>  	mutex_destroy(&thermal_list_lock);
> @@ -1626,4 +1627,10 @@ static int __init thermal_init(void)
>  	mutex_destroy(&poweroff_lock);
>  	return result;
>  }
> -fs_initcall(thermal_init);
> +
> +static int __init thermal_netlink_init(void)
> +{
> +	return genetlink_init();
> +}
> +core_initcall(thermal_init);
> +fs_initcall(thermal_netlink_init);
> 


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