Re: [PATCH dwarves] btf_encoder: add "distilled_base" BTF feature to split BTF generation

[Eduard Zingerman <eddyz87@gmail.com>]

On Fri, 2024-05-10 at 11:48 +0100, Alan Maguire wrote:
> Adding "distilled_base" to --btf_features when generating split BTF will
> create split and .BTF.base BTF - the latter allows us to map references
> from split BTF to base BTF, even if that base BTF has changed.  It does
> this by providing just enough information about the base types in the
> .BTF.base section.
> 
> Patch is applicable on the "next" branch of dwarves, and requires the
> libbpf from the series in [1]
> 
> Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
> 
> [1] https://lore.kernel.org/bpf/20240510103052.850012-1-alan.maguire@oracle.com/
> 
> ---

Acked-by: Eduard Zingerman <eddyz87@gmail.com>

[...]

> diff --git a/btf_encoder.c b/btf_encoder.c

[...]

> @@ -1297,7 +1298,7 @@ static int btf_encoder__write_elf(struct btf_encoder *encoder)
>  		if (shdr == NULL)
>  			continue;
>  		char *secname = elf_strptr(elf, strndx, shdr->sh_name);
> -		if (strcmp(secname, ".BTF") == 0) {
> +		if (strcmp(secname, btf_secname) == 0) {

Nit: comments in this function still refer to '.BTF' section.

>  			btf_data = elf_getdata(scn, btf_data);
>  			break;
>  		}

[...]