[PATCH] powercap: adjust init order

[PATCH] powercap: adjust init order

[Zhang Rui]

The MMIO RAPL interface driver depends on both powercap subsystem and
the intel_rapl_common code.
But when all of them are built in, the MMIO RAPL interface driver is
loaded before the later two and this breaks the system during boot.
This is because the powercap sysfs class is not registered and the
rapl_defaults ops is not set when built-in MMIO RAPL interface driver
gets loaded.

Fix this by adjusting the init order of powercap subsystem and the
intel_rapl_common code, so that their init functions are executed before
MMIO RAPL interface driver in any case.

Fixes: 555c45fe0d04 ("int340X/processor_thermal_device: add support for MMIO RAPL")
Reported-and-tested-by: Kenneth R. Crudup <kenny@panix.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/powercap/intel_rapl_common.c | 2 +-
 drivers/powercap/powercap_sys.c      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/powercap/intel_rapl_common.c b/drivers/powercap/intel_rapl_common.c
index 9fd6dd3..6df4818 100644
--- a/drivers/powercap/intel_rapl_common.c
+++ b/drivers/powercap/intel_rapl_common.c
@@ -1454,7 +1454,7 @@ static void __exit rapl_exit(void)
 	unregister_pm_notifier(&rapl_pm_notifier);
 }
 
-module_init(rapl_init);
+fs_initcall(rapl_init);
 module_exit(rapl_exit);
 
 MODULE_DESCRIPTION("Intel Runtime Average Power Limit (RAPL) common code");
diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c
index 540e8aa..f808c5f 100644
--- a/drivers/powercap/powercap_sys.c
+++ b/drivers/powercap/powercap_sys.c
@@ -671,7 +671,7 @@ static int __init powercap_init(void)
 	return class_register(&powercap_class);
 }
 
-device_initcall(powercap_init);
+fs_initcall(powercap_init);
 
 MODULE_DESCRIPTION("PowerCap sysfs Driver");
 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
-- 
2.7.4

Re: [PATCH] powercap: adjust init order

[Rafael J. Wysocki]

On Sunday, July 21, 2019 4:49:44 AM CEST Zhang Rui wrote:
> The MMIO RAPL interface driver depends on both powercap subsystem and
> the intel_rapl_common code.
> But when all of them are built in, the MMIO RAPL interface driver is
> loaded before the later two and this breaks the system during boot.
> This is because the powercap sysfs class is not registered and the
> rapl_defaults ops is not set when built-in MMIO RAPL interface driver
> gets loaded.
> 
> Fix this by adjusting the init order of powercap subsystem and the
> intel_rapl_common code, so that their init functions are executed before
> MMIO RAPL interface driver in any case.
> 
> Fixes: 555c45fe0d04 ("int340X/processor_thermal_device: add support for MMIO RAPL")
> Reported-and-tested-by: Kenneth R. Crudup <kenny@panix.com>
> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
> ---
>  drivers/powercap/intel_rapl_common.c | 2 +-
>  drivers/powercap/powercap_sys.c      | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/powercap/intel_rapl_common.c b/drivers/powercap/intel_rapl_common.c
> index 9fd6dd3..6df4818 100644
> --- a/drivers/powercap/intel_rapl_common.c
> +++ b/drivers/powercap/intel_rapl_common.c
> @@ -1454,7 +1454,7 @@ static void __exit rapl_exit(void)
>  	unregister_pm_notifier(&rapl_pm_notifier);
>  }
>  
> -module_init(rapl_init);
> +fs_initcall(rapl_init);
>  module_exit(rapl_exit);
>  
>  MODULE_DESCRIPTION("Intel Runtime Average Power Limit (RAPL) common code");
> diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c
> index 540e8aa..f808c5f 100644
> --- a/drivers/powercap/powercap_sys.c
> +++ b/drivers/powercap/powercap_sys.c
> @@ -671,7 +671,7 @@ static int __init powercap_init(void)
>  	return class_register(&powercap_class);
>  }
>  
> -device_initcall(powercap_init);
> +fs_initcall(powercap_init);
>  
>  MODULE_DESCRIPTION("PowerCap sysfs Driver");
>  MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
> 

Applied (with some subject and changelog tweaks), thanks!