[v3,2/5] ACPI/APEI: Remove static from apei_hest_parse()

From: leoliu-oc <leoliu-oc@zhaoxin.com>

Each dev with AER capability needs to call the apei_hest_parse function to
match and extract register values from HEST PCIe AER structures.
Therefore, remove static from apei_hest_parse() so that it can be called
in another file.

Signed-off-by: leoliu-oc <leoliu-oc@zhaoxin.com>
---
 drivers/acpi/apei/hest.c | 2 +-
 include/acpi/apei.h      | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

On Tue, Jul 04, 2023 at 08:05:17PM +0800, LeoLiu-oc wrote:
> From: leoliu-oc <leoliu-oc@zhaoxin.com>
> 
> Each dev with AER capability needs to call the apei_hest_parse function to
> match and extract register values from HEST PCIe AER structures.
> Therefore, remove static from apei_hest_parse() so that it can be called
> in another file.

Can you reword the subject line and commit log in the positive?
"Removing static" is a negative thing and it's semantically a bit too
low level -- it's clearly what the *code* does, but we can see that
from the patch, and what we want to know here is *why* it's important.
What this really does is expose apei_hest_parse() for use by other
subsystems.

Browsing the drivers/acpi commit log history, I see that Rafael adds
"()" after function names, so please do the same here (you did do that
once above, but not in the first line).

> Signed-off-by: leoliu-oc <leoliu-oc@zhaoxin.com>
> ---
>  drivers/acpi/apei/hest.c | 2 +-
>  include/acpi/apei.h      | 5 +++++
>  2 files changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
> index fb839a5c480ee..fd40c035c9b2e 100644
> --- a/drivers/acpi/apei/hest.c
> +++ b/drivers/acpi/apei/hest.c
> @@ -132,7 +132,7 @@ static bool hest_match_pci(struct acpi_hest_header *hest_hdr,
>  	return false;
>  }
>  
> -static int apei_hest_parse(apei_hest_func_t func, void *data)
> +int apei_hest_parse(apei_hest_func_t func, void *data)

If this is going to exported to the PCI subsystem, I think it needs
some kernel-doc.  For example, it's important to know that it stops
parsing the HEST if func returns anything non-zero.  This is how
pci_acpi_program_hest_aer_params() knows that it got good data that
matches the device it wants.

Given the fact that apei_hest_parse_aer() fills in the struct
acpi_hest_parse_aer_info with pointers into the HEST table data, it's
also important to know that this HEST table data is persistent.

>  {
>  	struct acpi_hest_header *hest_hdr;
>  	int i, rc, len;
> diff --git a/include/acpi/apei.h b/include/acpi/apei.h
> index 8a0b2b9edbafe..f975e4fe78fcb 100644
> --- a/include/acpi/apei.h
> +++ b/include/acpi/apei.h
> @@ -37,9 +37,14 @@ typedef int (*apei_hest_func_t)(struct acpi_hest_header *hest_hdr, void *data);
>  
>  #ifdef CONFIG_ACPI_APEI
>  void __init acpi_hest_init(void);
> +int apei_hest_parse(apei_hest_func_t func, void *data);
>  int apei_hest_parse_aer(struct acpi_hest_header *hest_hdr, void *data);
>  #else
>  static inline void acpi_hest_init(void) { }
> +static inline int apei_hest_parse(apei_hest_func_t func, void *data)
> +{
> +	return -EINVAL;
> +}
>  static inline int apei_hest_parse_aer(struct acpi_hest_header *hest_hdr, void *data)
>  {
>  	return -EINVAL;
> -- 
> 2.34.1
>

在 2023/8/11 7:17, Bjorn Helgaas 写道:
> On Tue, Jul 04, 2023 at 08:05:17PM +0800, LeoLiu-oc wrote:
>> From: leoliu-oc <leoliu-oc@zhaoxin.com>
>>
>> Each dev with AER capability needs to call the apei_hest_parse function to
>> match and extract register values from HEST PCIe AER structures.
>> Therefore, remove static from apei_hest_parse() so that it can be called
>> in another file.
> 
> Can you reword the subject line and commit log in the positive?
> "Removing static" is a negative thing and it's semantically a bit too
> low level -- it's clearly what the *code* does, but we can see that
> from the patch, and what we want to know here is *why* it's important.
> What this really does is expose apei_hest_parse() for use by other
> subsystems.
> 
> Browsing the drivers/acpi commit log history, I see that Rafael adds
> "()" after function names, so please do the same here (you did do that
> once above, but not in the first line).
> 


This function is required in patch v3 4/5 to traverse the HEST to find 
the HEST AER structures, so changed the definition to be global.

I will pay attention to this matter in the next version.

LeoLiu-oc

>> Signed-off-by: leoliu-oc <leoliu-oc@zhaoxin.com>
>> ---
>>   drivers/acpi/apei/hest.c | 2 +-
>>   include/acpi/apei.h      | 5 +++++
>>   2 files changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
>> index fb839a5c480ee..fd40c035c9b2e 100644
>> --- a/drivers/acpi/apei/hest.c
>> +++ b/drivers/acpi/apei/hest.c
>> @@ -132,7 +132,7 @@ static bool hest_match_pci(struct acpi_hest_header *hest_hdr,
>>   	return false;
>>   }
>>   
>> -static int apei_hest_parse(apei_hest_func_t func, void *data)
>> +int apei_hest_parse(apei_hest_func_t func, void *data)
> 
> If this is going to exported to the PCI subsystem, I think it needs
> some kernel-doc.  For example, it's important to know that it stops
> parsing the HEST if func returns anything non-zero.  This is how
> pci_acpi_program_hest_aer_params() knows that it got good data that
> matches the device it wants.
> 
> Given the fact that apei_hest_parse_aer() fills in the struct
> acpi_hest_parse_aer_info with pointers into the HEST table data, it's
> also important to know that this HEST table data is persistent.
>
Thank you suggestion, and I will consider carefully.

Best Regards.
LeoLiu-oc

>>   {
>>   	struct acpi_hest_header *hest_hdr;
>>   	int i, rc, len;
>> diff --git a/include/acpi/apei.h b/include/acpi/apei.h
>> index 8a0b2b9edbafe..f975e4fe78fcb 100644
>> --- a/include/acpi/apei.h
>> +++ b/include/acpi/apei.h
>> @@ -37,9 +37,14 @@ typedef int (*apei_hest_func_t)(struct acpi_hest_header *hest_hdr, void *data);
>>   
>>   #ifdef CONFIG_ACPI_APEI
>>   void __init acpi_hest_init(void);
>> +int apei_hest_parse(apei_hest_func_t func, void *data);
>>   int apei_hest_parse_aer(struct acpi_hest_header *hest_hdr, void *data);
>>   #else
>>   static inline void acpi_hest_init(void) { }
>> +static inline int apei_hest_parse(apei_hest_func_t func, void *data)
>> +{
>> +	return -EINVAL;
>> +}
>>   static inline int apei_hest_parse_aer(struct acpi_hest_header *hest_hdr, void *data)
>>   {
>>   	return -EINVAL;
>> -- 
>> 2.34.1
>>