RFC: Add GNU_PROPERTY_1_NEEDED_TRANSPARENT_HUGEPAGE

[Florian Weimer]

* H. J. Lu via Gnu-gabi:

> There are kernel ELF loader patch:
>
> https://patchew.org/linux/20260313005211.882831-1-r@hev.cc/
>
> and glibc patches:
>
> https://patchwork.sourceware.org/project/glibc/list/?series=59524
>
> to load PT_LOAD segment with THP.  But there is no per-application
> control for kernel ELF loader.  For glibc, we can use
>
> $ GLIBC_TUNABLES=glibc.elf.thp=1 application
>
> to enable THP on application.  But it requires setting GLIBC_TUNABLES
> at run-time.
>
> Add GNU_PROPERTY_1_NEEDED_TRANSPARENT_HUGEPAGE:
>
> /* Set if the object file should be loaded with transparent huge pages
>    if possible.  */
> #define GNU_PROPERTY_1_NEEDED_TRANSPARENT_HUGEPAGE (1U << 1)
>
> to GNU_PROPERTY_1_NEEDED.

Can we use p_align as the signal?

Thanks,
Florian