Commit 8991de90 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

mm/huge_memory: remove page_deferred_list() 

Use folio->_deferred_list directly.

Link: https://lkml.kernel.org/r/20230111142915.1001531-26-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 4375a553

include/linux/huge_mm.h

+0 −8
Original line number Diff line number Diff line
@@ -293,14 +293,6 @@ static inline bool thp_migration_supported(void) 
	return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION);

}



static inline struct list_head *page_deferred_list(struct page *page)

{

	struct folio *folio = (struct folio *)page;



	VM_BUG_ON_FOLIO(folio_order(folio) < 2, folio);

	return &folio->_deferred_list;

}



#else /* CONFIG_TRANSPARENT_HUGEPAGE */

#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })

#define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })

mm/huge_memory.c

+17 −17
Original line number Diff line number Diff line
@@ -580,12 +580,10 @@ static inline struct deferred_split *get_deferred_split_queue(struct page *page) 


void prep_transhuge_page(struct page *page)

{

	/*

	 * we use page->mapping and page->index in second tail page

	 * as list_head: assuming THP order >= 2

	 */

	struct folio *folio = (struct folio *)page;



	INIT_LIST_HEAD(page_deferred_list(page));

	VM_BUG_ON_FOLIO(folio_order(folio) < 2, folio);

	INIT_LIST_HEAD(&folio->_deferred_list);

	set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);

}
@@ -2802,13 +2800,14 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) 


void free_transhuge_page(struct page *page)

{

	struct folio *folio = (struct folio *)page;

	struct deferred_split *ds_queue = get_deferred_split_queue(page);

	unsigned long flags;



	spin_lock_irqsave(&ds_queue->split_queue_lock, flags);

	if (!list_empty(page_deferred_list(page))) {

	if (!list_empty(&folio->_deferred_list)) {

		ds_queue->split_queue_len--;

		list_del(page_deferred_list(page));

		list_del(&folio->_deferred_list);

	}

	spin_unlock_irqrestore(&ds_queue->split_queue_lock, flags);

	free_compound_page(page);
@@ -2816,38 +2815,39 @@ void free_transhuge_page(struct page *page) 


void deferred_split_huge_page(struct page *page)

{

	struct folio *folio = page_folio(page);

	struct deferred_split *ds_queue = get_deferred_split_queue(page);

#ifdef CONFIG_MEMCG

	struct mem_cgroup *memcg = page_memcg(compound_head(page));

	struct mem_cgroup *memcg = folio_memcg(folio);

#endif

	unsigned long flags;



	VM_BUG_ON_PAGE(!PageTransHuge(page), page);

	VM_BUG_ON_FOLIO(folio_order(folio) < 2, folio);



	/*

	 * The try_to_unmap() in page reclaim path might reach here too,

	 * this may cause a race condition to corrupt deferred split queue.

	 * And, if page reclaim is already handling the same page, it is

	 * And, if page reclaim is already handling the same folio, it is

	 * unnecessary to handle it again in shrinker.

	 *

	 * Check PageSwapCache to determine if the page is being

	 * handled by page reclaim since THP swap would add the page into

	 * Check the swapcache flag to determine if the folio is being

	 * handled by page reclaim since THP swap would add the folio into

	 * swap cache before calling try_to_unmap().

	 */

	if (PageSwapCache(page))

	if (folio_test_swapcache(folio))

		return;



	if (!list_empty(page_deferred_list(page)))

	if (!list_empty(&folio->_deferred_list))

		return;



	spin_lock_irqsave(&ds_queue->split_queue_lock, flags);

	if (list_empty(page_deferred_list(page))) {

	if (list_empty(&folio->_deferred_list)) {

		count_vm_event(THP_DEFERRED_SPLIT_PAGE);

		list_add_tail(page_deferred_list(page), &ds_queue->split_queue);

		list_add_tail(&folio->_deferred_list, &ds_queue->split_queue);

		ds_queue->split_queue_len++;

#ifdef CONFIG_MEMCG

		if (memcg)

			set_shrinker_bit(memcg, page_to_nid(page),

			set_shrinker_bit(memcg, folio_nid(folio),

					 deferred_split_shrinker.id);

#endif

	}