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

From: Anshuman Khandual
Date: Wed Jun 15 2022 - 01:02:39 EST




On 6/11/22 08:44, Hugh Dickins wrote:
> 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@xxxxxxxxxx>
>
> 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()")

The same reasoning should also be applicable for other calls sites
for transhuge_vma_enabled(). Should not they be dropped as well ?

>
> 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
>