The WMI core already knows the instance count of a WMI guid.
Use this information instead of querying all possible instances
which is slow and might be unreliable.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
---
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 0b277b7e37dd..63c78b4d8258 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -388,16 +388,13 @@ union acpi_object *hp_get_wmiobj_pointer(int instance_id, const char *guid_strin
  */
 int hp_get_instance_count(const char *guid_string)
 {
-	union acpi_object *wmi_obj = NULL;
-	int i = 0;
+	int ret;

-	do {
-		kfree(wmi_obj);
-		wmi_obj = hp_get_wmiobj_pointer(i, guid_string);
-		i++;
-	} while (wmi_obj);
+	ret = wmi_instance_count(guid_string);
+	if (ret < 0)
+		return 0;

-	return i - 1;
+	return ret;
 }

 /**
--
2.39.5

On Mon, 3 Feb 2025, Armin Wolf wrote:

> The WMI core already knows the instance count of a WMI guid.
> Use this information instead of querying all possible instances
> which is slow and might be unreliable.
> 
> Signed-off-by: Armin Wolf <W_Armin@gmx.de>
> ---
>  drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> index 0b277b7e37dd..63c78b4d8258 100644
> --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> @@ -388,16 +388,13 @@ union acpi_object *hp_get_wmiobj_pointer(int instance_id, const char *guid_strin
>   */
>  int hp_get_instance_count(const char *guid_string)
>  {
> -	union acpi_object *wmi_obj = NULL;
> -	int i = 0;
> +	int ret;
> 
> -	do {
> -		kfree(wmi_obj);
> -		wmi_obj = hp_get_wmiobj_pointer(i, guid_string);
> -		i++;
> -	} while (wmi_obj);
> +	ret = wmi_instance_count(guid_string);
> +	if (ret < 0)
> +		return 0;
> 
> -	return i - 1;
> +	return ret;
>  }

Hi Armin,

While it is the existing way of doing things, I don't like how the error 
is not properly passed on here. And if the error handling is pushed 
upwards to the calling sites, then this entire function becomes useless 
and wmi_instance_count() could be used directly in the callers.

-- 
 i.

Am 04.02.25 um 11:37 schrieb Ilpo Järvinen:

> On Mon, 3 Feb 2025, Armin Wolf wrote:
>
>> The WMI core already knows the instance count of a WMI guid.
>> Use this information instead of querying all possible instances
>> which is slow and might be unreliable.
>>
>> Signed-off-by: Armin Wolf <W_Armin@gmx.de>
>> ---
>>   drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 13 +++++--------
>>   1 file changed, 5 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
>> index 0b277b7e37dd..63c78b4d8258 100644
>> --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
>> +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
>> @@ -388,16 +388,13 @@ union acpi_object *hp_get_wmiobj_pointer(int instance_id, const char *guid_strin
>>    */
>>   int hp_get_instance_count(const char *guid_string)
>>   {
>> -	union acpi_object *wmi_obj = NULL;
>> -	int i = 0;
>> +	int ret;
>>
>> -	do {
>> -		kfree(wmi_obj);
>> -		wmi_obj = hp_get_wmiobj_pointer(i, guid_string);
>> -		i++;
>> -	} while (wmi_obj);
>> +	ret = wmi_instance_count(guid_string);
>> +	if (ret < 0)
>> +		return 0;
>>
>> -	return i - 1;
>> +	return ret;
>>   }
> Hi Armin,
>
> While it is the existing way of doing things, I don't like how the error
> is not properly passed on here. And if the error handling is pushed
> upwards to the calling sites, then this entire function becomes useless
> and wmi_instance_count() could be used directly in the callers.
>
The thing is that for the hp-bioscfg driver, a missing WMI GUID is not an error.
In this case 0 instances are available.

I would keep this function for now.

Thanks,
Armin Wolf

On Tue, 4 Feb 2025, Armin Wolf wrote:

> Am 04.02.25 um 11:37 schrieb Ilpo Järvinen:
> 
> > On Mon, 3 Feb 2025, Armin Wolf wrote:
> > 
> > > The WMI core already knows the instance count of a WMI guid.
> > > Use this information instead of querying all possible instances
> > > which is slow and might be unreliable.
> > > 
> > > Signed-off-by: Armin Wolf <W_Armin@gmx.de>
> > > ---
> > >   drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 13 +++++--------
> > >   1 file changed, 5 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> > > b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> > > index 0b277b7e37dd..63c78b4d8258 100644
> > > --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> > > +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> > > @@ -388,16 +388,13 @@ union acpi_object *hp_get_wmiobj_pointer(int
> > > instance_id, const char *guid_strin
> > >    */
> > >   int hp_get_instance_count(const char *guid_string)
> > >   {
> > > -	union acpi_object *wmi_obj = NULL;
> > > -	int i = 0;
> > > +	int ret;
> > > 
> > > -	do {
> > > -		kfree(wmi_obj);
> > > -		wmi_obj = hp_get_wmiobj_pointer(i, guid_string);
> > > -		i++;
> > > -	} while (wmi_obj);
> > > +	ret = wmi_instance_count(guid_string);
> > > +	if (ret < 0)
> > > +		return 0;
> > > 
> > > -	return i - 1;
> > > +	return ret;
> > >   }
> > Hi Armin,
> > 
> > While it is the existing way of doing things, I don't like how the error
> > is not properly passed on here. And if the error handling is pushed
> > upwards to the calling sites, then this entire function becomes useless
> > and wmi_instance_count() could be used directly in the callers.
>
> The thing is that for the hp-bioscfg driver, a missing WMI GUID is not an
> error.
> In this case 0 instances are available.
> 
> I would keep this function for now.

Okay, fine.

-- 
 i.