Commit a0d3374b authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

mm/swap: convert __read_swap_cache_async() to use a folio 

Remove a few hidden (and one visible) calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-12-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent bdb0ed54

mm/swap_state.c

+19 −19
Original line number Diff line number Diff line
@@ -411,7 +411,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
			bool *new_page_allocated)

{

	struct swap_info_struct *si;

	struct page *page;

	struct folio *folio;

	void *shadow = NULL;



	*new_page_allocated = false;
@@ -426,11 +426,11 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
		si = get_swap_device(entry);

		if (!si)

			return NULL;

		page = find_get_page(swap_address_space(entry),

		folio = filemap_get_folio(swap_address_space(entry),

						swp_offset(entry));

		put_swap_device(si);

		if (page)

			return page;

		if (folio)

			return folio_file_page(folio, swp_offset(entry));



		/*

		 * Just skip read ahead for unused swap slot.
@@ -448,8 +448,8 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
		 * before marking swap_map SWAP_HAS_CACHE, when -EEXIST will

		 * cause any racers to loop around until we add it to cache.

		 */

		page = alloc_page_vma(gfp_mask, vma, addr);

		if (!page)

		folio = vma_alloc_folio(gfp_mask, 0, vma, addr, false);

		if (!folio)

			return NULL;



		/*
@@ -459,7 +459,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
		if (!err)

			break;



		put_page(page);

		folio_put(folio);

		if (err != -EEXIST)

			return NULL;
@@ -477,30 +477,30 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
	 * The swap entry is ours to swap in. Prepare the new page.

	 */



	__SetPageLocked(page);

	__SetPageSwapBacked(page);

	__folio_set_locked(folio);

	__folio_set_swapbacked(folio);



	if (mem_cgroup_swapin_charge_page(page, NULL, gfp_mask, entry))

	if (mem_cgroup_swapin_charge_page(&folio->page, NULL, gfp_mask, entry))

		goto fail_unlock;



	/* May fail (-ENOMEM) if XArray node allocation failed. */

	if (add_to_swap_cache(page, entry, gfp_mask & GFP_RECLAIM_MASK, &shadow))

	if (add_to_swap_cache(&folio->page, entry, gfp_mask & GFP_RECLAIM_MASK, &shadow))

		goto fail_unlock;



	mem_cgroup_swapin_uncharge_swap(entry);



	if (shadow)

		workingset_refault(page_folio(page), shadow);

		workingset_refault(folio, shadow);



	/* Caller will initiate read into locked page */

	lru_cache_add(page);

	/* Caller will initiate read into locked folio */

	folio_add_lru(folio);

	*new_page_allocated = true;

	return page;

	return &folio->page;



fail_unlock:

	put_swap_page(page, entry);

	unlock_page(page);

	put_page(page);

	put_swap_page(&folio->page, entry);

	folio_unlock(folio);

	folio_put(folio);

	return NULL;

}