Re: [PATCH v3 4/6] mm: Introduce a pageflag for partially mapped folios

Usama Arif
2024-08-14T10:20:43Z

On 14/08/2024 04:30, Yu Zhao wrote:
>> @@ -3558,7 +3564,6 @@ static unsigned long deferred_split_scan(struct shrinker *shrink,
>> next:
>> folio_put(folio);
>> }
>> -
>
> Unintentional change above?

Yes, unintended new line, will fix it.
>
>> spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
>> list_splice_tail(&list, &ds_queue->split_queue);
>> spin_unlock_irqrestore(&ds_queue->split_queue_lock, flags);
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 1fdd9eab240c..2ae2d9a18e40 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -1758,6 +1758,7 @@ static void __update_and_free_hugetlb_folio(struct hstate *h,
>> free_gigantic_folio(folio, huge_page_order(h));
>> } else {
>> INIT_LIST_HEAD(&folio->_deferred_list);
>> + folio_clear_partially_mapped(folio);
>
> Why does it need to clear a flag that should never be set on hugeTLB folios?
>
> HugeTLB does really use _deferred_list -- it clears it only to avoid
> bad_page() because of the overlapping fields:
> void *_hugetlb_subpool;
> void *_hugetlb_cgroup;

Yes, thats right, will remove it. Thanks!