Re: [PATCH] mm/shmem.c: use helper transhuge_vma_enabled()

[Hugh Dickins <hughd@google.com>]

On Sat, 11 Jun 2022, Miaohe Lin wrote:

> Use helper transhuge_vma_enabled() to check whether transhuge is enable
> on vma. Minor readability improvement.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>

No thanks, that's a readability regression, forcing reader
to go and look up what transhuge_vma_enabled() actually means.

What you call a helper, I call an obfuscator - as I implied in
b9e2faaf6fa0 ("huge tmpfs: revert shmem's use of transhuge_vma_enabled()")

Hugh

> ---
>  mm/shmem.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/mm/shmem.c b/mm/shmem.c
> index 133c67057d41..59cc2e980c95 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -480,8 +480,7 @@ bool shmem_is_huge(struct vm_area_struct *vma,
>  		return false;
>  	if (shmem_huge == SHMEM_HUGE_DENY)
>  		return false;
> -	if (vma && ((vma->vm_flags & VM_NOHUGEPAGE) ||
> -	    test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)))
> +	if (vma && !transhuge_vma_enabled(vma, vma->vm_flags))
>  		return false;
>  	if (shmem_huge == SHMEM_HUGE_FORCE)
>  		return true;
> -- 
> 2.23.0