Re: [PATCH mm-unstable v3 06/10] mm/hugetlb: convert add_hugetlb_page() to folios and add hugetlb_cma_folio()

[Sidhartha Kumar <sidhartha.kumar@oracle.com>]

On 11/19/22 10:59 AM, Tarun Sahu wrote:
> Hi,
> Though it is already merged, it is just comment thing.

This series will need another version based on other feedback that I 
got. I'll be sure to change the comment in the next version.

Thanks,

Sidhartha Kumar

> On Nov 17 2022, Sidhartha Kumar wrote:
>> Convert add_hugetlb_page() to take in a folio, also convert
>> hugetlb_cma_page() to take in a folio.
>>
>> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
>> ---
>>   mm/hugetlb.c | 40 ++++++++++++++++++++--------------------
>>   1 file changed, 20 insertions(+), 20 deletions(-)
>>
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 80301fab56d8..bf36aa8e6072 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -54,13 +54,13 @@ struct hstate hstates[HUGE_MAX_HSTATE];
>>   #ifdef CONFIG_CMA
>>   static struct cma *hugetlb_cma[MAX_NUMNODES];
>>   static unsigned long hugetlb_cma_size_in_node[MAX_NUMNODES] __initdata;
>> -static bool hugetlb_cma_page(struct page *page, unsigned int order)
>> +static bool hugetlb_cma_folio(struct folio *folio, unsigned int order)
>>   {
>> -	return cma_pages_valid(hugetlb_cma[page_to_nid(page)], page,
>> +	return cma_pages_valid(hugetlb_cma[folio_nid(folio)], &folio->page,
>>   				1 << order);
>>   }
>>   #else
>> -static bool hugetlb_cma_page(struct page *page, unsigned int order)
>> +static bool hugetlb_cma_folio(struct folio *folio, unsigned int order)
>>   {
>>   	return false;
>>   }
>> @@ -1506,17 +1506,17 @@ static void remove_hugetlb_folio_for_demote(struct hstate *h, struct folio *foli
>>   	__remove_hugetlb_folio(h, folio, adjust_surplus, true);
>>   }
>>   
>> -static void add_hugetlb_page(struct hstate *h, struct page *page,
>> +static void add_hugetlb_folio(struct hstate *h, struct folio *folio,
>>   			     bool adjust_surplus)
>>   {
>>   	int zeroed;
>> -	int nid = page_to_nid(page);
>> +	int nid = folio_nid(folio);
>>   
>> -	VM_BUG_ON_PAGE(!HPageVmemmapOptimized(page), page);
>> +	VM_BUG_ON_FOLIO(!folio_test_hugetlb_vmemmap_optimized(folio), folio);
>>   
>>   	lockdep_assert_held(&hugetlb_lock);
>>   
>> -	INIT_LIST_HEAD(&page->lru);
>> +	INIT_LIST_HEAD(&folio->lru);
>>   	h->nr_huge_pages++;
>>   	h->nr_huge_pages_node[nid]++;
>>   
>> @@ -1525,21 +1525,21 @@ static void add_hugetlb_page(struct hstate *h, struct page *page,
>>   		h->surplus_huge_pages_node[nid]++;
>>   	}
>>   
>> -	set_compound_page_dtor(page, HUGETLB_PAGE_DTOR);
>> -	set_page_private(page, 0);
>> +	folio_set_compound_dtor(folio, HUGETLB_PAGE_DTOR);
>> +	folio_change_private(folio, 0);
>>   	/*
>>   	 * We have to set HPageVmemmapOptimized again as above
>                             ^
> This can be changed to folio version of itself.
>
>> -	 * set_page_private(page, 0) cleared it.
>> +	 * folio_change_private(folio, 0) cleared it.
>>   	 */
>> -	SetHPageVmemmapOptimized(page);
>> +	folio_set_hugetlb_vmemmap_optimized(folio);
>>   
>>   	/*
>> -	 * This page is about to be managed by the hugetlb allocator and
>> +	 * This folio is about to be managed by the hugetlb allocator and
>>   	 * should have no users.  Drop our reference, and check for others
>>   	 * just in case.
>>   	 */
>> -	zeroed = put_page_testzero(page);
>> -	if (!zeroed)
>> +	zeroed = folio_put_testzero(folio);
>> +	if (unlikely(!zeroed))
>>   		/*
>>   		 * It is VERY unlikely soneone else has taken a ref on
>>   		 * the page.  In this case, we simply return as the
>> @@ -1548,8 +1548,8 @@ static void add_hugetlb_page(struct hstate *h, struct page *page,
>>   		 */
>>   		return;
>>   
>> -	arch_clear_hugepage_flags(page);
>> -	enqueue_huge_page(h, page);
>> +	arch_clear_hugepage_flags(&folio->page);
>> +	enqueue_huge_page(h, &folio->page);
>>   }
>>   
>>   static void __update_and_free_page(struct hstate *h, struct page *page)
>> @@ -1575,7 +1575,7 @@ static void __update_and_free_page(struct hstate *h, struct page *page)
>>   		 * page and put the page back on the hugetlb free list and treat
>>   		 * as a surplus page.
>>   		 */
>> -		add_hugetlb_page(h, page, true);
>> +		add_hugetlb_folio(h, page_folio(page), true);
>>   		spin_unlock_irq(&hugetlb_lock);
>>   		return;
>>   	}
>> @@ -1600,7 +1600,7 @@ static void __update_and_free_page(struct hstate *h, struct page *page)
>>   	 * need to be given back to CMA in free_gigantic_page.
>>   	 */
>>   	if (hstate_is_gigantic(h) ||
>> -	    hugetlb_cma_page(page, huge_page_order(h))) {
>> +	    hugetlb_cma_folio(folio, huge_page_order(h))) {
>>   		destroy_compound_gigantic_folio(folio, huge_page_order(h));
>>   		free_gigantic_page(page, huge_page_order(h));
>>   	} else {
>> @@ -2184,7 +2184,7 @@ int dissolve_free_huge_page(struct page *page)
>>   			update_and_free_hugetlb_folio(h, folio, false);
>>   		} else {
>>   			spin_lock_irq(&hugetlb_lock);
>> -			add_hugetlb_page(h, &folio->page, false);
>> +			add_hugetlb_folio(h, folio, false);
>>   			h->max_huge_pages++;
>>   			spin_unlock_irq(&hugetlb_lock);
>>   		}
>> @@ -3451,7 +3451,7 @@ static int demote_free_huge_page(struct hstate *h, struct page *page)
>>   		/* Allocation of vmemmmap failed, we can not demote page */
>>   		spin_lock_irq(&hugetlb_lock);
>>   		set_page_refcounted(page);
>> -		add_hugetlb_page(h, page, false);
>> +		add_hugetlb_folio(h, page_folio(page), false);
>>   		return rc;
>>   	}
>>   
>> -- 
>> 2.38.1
>>