[PATCH] hugetlb: allow to free gigantic pages regardless of the configuration

[Will Deacon]

On Thu, Jan 17, 2019 at 06:39:53PM +0000, Alexandre Ghiti wrote:
> From: Alexandre Ghiti <alex at ghiti.fr>
> 
> On systems without CMA or (MEMORY_ISOLATION && COMPACTION) activated but
> that support gigantic pages, boottime reserved gigantic pages can not be
> freed at all. This patchs simply enables the possibility to hand back
> those pages to memory allocator.
> 
> This commit then renames gigantic_page_supported and
> ARCH_HAS_GIGANTIC_PAGE to make them more accurate. Indeed, those values
> being false does not mean that the system cannot use gigantic pages: it
> just means that runtime allocation of gigantic pages is not supported,
> one can still allocate boottime gigantic pages if the architecture supports
> it.
> 
> Signed-off-by: Alexandre Ghiti <alex at ghiti.fr>
> ---
> 
> - Compiled on all architectures
> - Tested on riscv architecture
> 
>  arch/arm64/Kconfig                           |  2 +-
>  arch/arm64/include/asm/hugetlb.h             |  7 +++--

The arm64 bits look straightforward enough to me...

Acked-by: Will Deacon <will.deacon at arm.com>

Will