Re: [PATCH dwarves 3/4] dwarf_loader: support btf_type_tag attribute

[Yonghong Song <yhs@fb.com>]

On 11/18/21 5:00 AM, Arnaldo Carvalho de Melo wrote:
> Em Wed, Nov 17, 2021 at 12:22:29PM -0800, Yonghong Song escreveu:
>> This patch implemented dwarf_loader support. If a pointer type
>> contains DW_TAG_LLVM_annotation tags, a new type
>> btf_type_tag_ptr_type will be created which will store
>> the pointer tag itself and all DW_TAG_LLVM_annotation tags.
>> During recoding stage, the type chain will be formed properly
>> based on the above example.
>>
>> An option "--skip_encoding_btf_type_tag" is added to disable
>> this new functionality.
>>
>>    [1] https://reviews.llvm.org/D111199
>>    [2] https://reviews.llvm.org/D113222
>>    [3] https://reviews.llvm.org/D113496
> 
> You forgot to add your S-o-B and to add this entry to
> man-pages/pahole.1, I'm fixing both cases, bellow is a followup
> patch, I'll add one as well for the recently added
> --skip_encoding_btf_decl_tag.

Thanks for the fixup! It is my fault as I never changed man page
before and not aware of that.

> 
> - Arnaldo
> 
> commit 9c3101db76acf364607d90adb3052e34d81fa1bd
> Author: Arnaldo Carvalho de Melo <acme@redhat.com>
> Date:   Thu Nov 18 09:56:35 2021 -0300
> 
>      man pages: Add missing --skip_encoding_btf_type_tag entry
>      
>      In the past we saw the value of being able to disable specific features
>      due to problems in in its implementation, allowing users to use a subset
>      of functionality, without the problematic one.
>      
>      Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> 
> diff --git a/man-pages/pahole.1 b/man-pages/pahole.1
> index edcf58b8ca5814a3..f9f64b67945b45cb 100644
> --- a/man-pages/pahole.1
> +++ b/man-pages/pahole.1
> @@ -197,6 +197,10 @@ the debugging information.
>   .B \-\-skip_encoding_btf_vars
>   Do not encode VARs in BTF.
>   
> +.TP
> +.B \-\-skip_encoding_btf_type_tag
> +Do not encode type tags in BTF.
> +
>   .TP
>   .B \-j, \-\-jobs=N
>   Run N jobs in parallel. Defaults to number of online processors + 10% (like
> 
> 

LGTM.

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