Re: [PATCH 1/3] mm: pgtable: correct the wrong comment about ptdesc->__page_flags

Qi Zheng
2024-03-27T02:01:00Z

On 2024/3/27 03:12, Vishal Moola wrote:
> On Mon, Mar 04, 2024 at 07:07:18PM +0800, Qi Zheng wrote:
>> The commit 32cc0b7c9d50 ("powerpc: add pte_free_defer() for pgtables
>> sharing page") introduced the use of PageActive flag to page table
>> fragments tracking, so the ptdesc->__page_flags is not unused, so
>> correct the wrong comment.
>
> Thanks for catching this!
>
> In regards to naming, we're trying to prefix unused variables with
> __underscores so I'd prefer to see the __ eliminated from the
> ptdesc->page_flags field here as well. This doesn't warrant a fix
> as it is already in 6.9-rc1, but is something to keep in
> mind for the future.

Got it.

> Aside from that, LGTM.
>
> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

Thanks!

>> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
>> ---
>> include/linux/mm_types.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
>> index a7223ba3ea1e..5ea77969daae 100644
>> --- a/include/linux/mm_types.h
>> +++ b/include/linux/mm_types.h
>> @@ -419,7 +419,7 @@ FOLIO_MATCH(compound_head, _head_2a);
>>
>> /**
>> * struct ptdesc - Memory descriptor for page tables.
>> - * @__page_flags: Same as page flags. Unused for page tables.
>> + * @__page_flags: Same as page flags. Powerpc only.
>> * @pt_rcu_head: For freeing page table pages.
>> * @pt_list: List of used page tables. Used for s390 and x86.
>> * @_pt_pad_1: Padding that aliases with page's compound head.
>> --
>> 2.30.2
>>