[PATCH dwarves] Documentation/pahole: describe expected use of 'default'

[PATCH dwarves] Documentation/pahole: describe expected use of 'default'

[Alan Maguire]

the 'default' --btf_features option is useful for testing the latest
set of standard features used for BTF encoding, but will not be used
in the kernel Makefile.btf.  It functions as a useful shortcut for
testing the latest set of standard features.  Describe this in the manual
page.

Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
---
 man-pages/pahole.1 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/man-pages/pahole.1 b/man-pages/pahole.1
index e3c58e0..19bf197 100644
--- a/man-pages/pahole.1
+++ b/man-pages/pahole.1
@@ -290,7 +290,7 @@ Allow using all the BTF features supported by pahole.
 
 .TP
 .B \-\-btf_features=FEATURE_LIST
-Encode BTF using the specified feature list, or specify 'default' for all standard features supported.  This option can be used as an alternative to unsing multiple BTF-related options. Supported standard features are
+Encode BTF using the specified feature list, or specify 'default' for all standard features supported.  This option can be used as an alternative to using multiple BTF-related options, and 'default' represents the standard set of BTF features that are in use for kernel BTF generation, so is useful as a shortcut for testing the latest set of standard features.  However kernel builds will call out specific features rather than using 'default' to ensure that the desired features are enabled regardless of pahole version and associated 'default' set.  Supported standard features are
 
 .nf
 	encode_force       Ignore invalid symbols when encoding BTF; for example
-- 
2.39.3

Re: [PATCH dwarves] Documentation/pahole: describe expected use of 'default'

[Arnaldo Carvalho de Melo]

On Tue, Apr 30, 2024 at 10:55:01AM +0100, Alan Maguire wrote:
> the 'default' --btf_features option is useful for testing the latest
> set of standard features used for BTF encoding, but will not be used
> in the kernel Makefile.btf.  It functions as a useful shortcut for
> testing the latest set of standard features.  Describe this in the manual
> page.

Thanks, applied!

FYI: all this is now on the master branch, it sat for a good time on the
'next' branch, got tested by multiple people and by the libbpf CI at
github.

Plans now are to get the kfunc stuff as the last feature for 1.26.

- Arnaldo
 
> Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
> ---
>  man-pages/pahole.1 | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/man-pages/pahole.1 b/man-pages/pahole.1
> index e3c58e0..19bf197 100644
> --- a/man-pages/pahole.1
> +++ b/man-pages/pahole.1
> @@ -290,7 +290,7 @@ Allow using all the BTF features supported by pahole.
>  
>  .TP
>  .B \-\-btf_features=FEATURE_LIST
> -Encode BTF using the specified feature list, or specify 'default' for all standard features supported.  This option can be used as an alternative to unsing multiple BTF-related options. Supported standard features are
> +Encode BTF using the specified feature list, or specify 'default' for all standard features supported.  This option can be used as an alternative to using multiple BTF-related options, and 'default' represents the standard set of BTF features that are in use for kernel BTF generation, so is useful as a shortcut for testing the latest set of standard features.  However kernel builds will call out specific features rather than using 'default' to ensure that the desired features are enabled regardless of pahole version and associated 'default' set.  Supported standard features are
>  
>  .nf
>  	encode_force       Ignore invalid symbols when encoding BTF; for example
> -- 
> 2.39.3

Re: [PATCH dwarves] Documentation/pahole: describe expected use of 'default'

[Alan Maguire]

On 30/04/2024 15:47, Arnaldo Carvalho de Melo wrote:
> On Tue, Apr 30, 2024 at 10:55:01AM +0100, Alan Maguire wrote:
>> the 'default' --btf_features option is useful for testing the latest
>> set of standard features used for BTF encoding, but will not be used
>> in the kernel Makefile.btf.  It functions as a useful shortcut for
>> testing the latest set of standard features.  Describe this in the manual
>> page.
> 
> Thanks, applied!
> 
> FYI: all this is now on the master branch, it sat for a good time on the
> 'next' branch, got tested by multiple people and by the libbpf CI at
> github.
> 
> Plans now are to get the kfunc stuff as the last feature for 1.26.
>

sounds good! I just sent the patch to bpf-next to move to using
--btf_features for pahole v1.26 and later [1]

Alan

[1]
https://lore.kernel.org/bpf/20240501175035.2476830-1-alan.maguire@oracle.com/

> - Arnaldo
>  
>> Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
>> Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
>> ---
>>  man-pages/pahole.1 | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/man-pages/pahole.1 b/man-pages/pahole.1
>> index e3c58e0..19bf197 100644
>> --- a/man-pages/pahole.1
>> +++ b/man-pages/pahole.1
>> @@ -290,7 +290,7 @@ Allow using all the BTF features supported by pahole.
>>  
>>  .TP
>>  .B \-\-btf_features=FEATURE_LIST
>> -Encode BTF using the specified feature list, or specify 'default' for all standard features supported.  This option can be used as an alternative to unsing multiple BTF-related options. Supported standard features are
>> +Encode BTF using the specified feature list, or specify 'default' for all standard features supported.  This option can be used as an alternative to using multiple BTF-related options, and 'default' represents the standard set of BTF features that are in use for kernel BTF generation, so is useful as a shortcut for testing the latest set of standard features.  However kernel builds will call out specific features rather than using 'default' to ensure that the desired features are enabled regardless of pahole version and associated 'default' set.  Supported standard features are
>>  
>>  .nf
>>  	encode_force       Ignore invalid symbols when encoding BTF; for example
>> -- 
>> 2.39.3