Commit a4575c41 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

mm: convert swap_cluster_readahead and swap_vma_readahead to return a folio 

shmem_swapin_cluster() immediately converts the page back to a folio, and
swapin_readahead() may as well call folio_file_page() once instead of
having each function call it.

[willy@infradead.org: avoid NULL pointer deref]
  Link: https://lkml.kernel.org/r/ZYI7OcVlM1voKfBl@casper.infradead.org
Link: https://lkml.kernel.org/r/20231213215842.671461-14-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 6e03492e

mm/shmem.c

+3 −5
Original line number Diff line number Diff line
@@ -1570,15 +1570,13 @@ static struct folio *shmem_swapin_cluster(swp_entry_t swap, gfp_t gfp, 
{

	struct mempolicy *mpol;

	pgoff_t ilx;

	struct page *page;

	struct folio *folio;



	mpol = shmem_get_pgoff_policy(info, index, 0, &ilx);

	page = swap_cluster_readahead(swap, gfp, mpol, ilx);

	folio = swap_cluster_readahead(swap, gfp, mpol, ilx);

	mpol_cond_put(mpol);



	if (!page)

		return NULL;

	return page_folio(page);

	return folio;

}



/*

mm/swap.h

+3 −3
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ struct folio *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_flags,

		struct mempolicy *mpol, pgoff_t ilx, bool *new_page_allocated,

		bool skip_if_exists);

struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,

struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,

		struct mempolicy *mpol, pgoff_t ilx);

struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,

			      struct vm_fault *vmf);
@@ -80,7 +80,7 @@ static inline void show_swap_cache_info(void) 
{

}



static inline struct page *swap_cluster_readahead(swp_entry_t entry,

static inline struct folio *swap_cluster_readahead(swp_entry_t entry,

			gfp_t gfp_mask, struct mempolicy *mpol, pgoff_t ilx)

{

	return NULL;

mm/swap_state.c

+13 −11
Original line number Diff line number Diff line
@@ -620,7 +620,7 @@ static unsigned long swapin_nr_pages(unsigned long offset) 
 * @mpol: NUMA memory allocation policy to be applied

 * @ilx: NUMA interleave index, for use only when MPOL_INTERLEAVE

 *

 * Returns the struct page for entry and addr, after queueing swapin.

 * Returns the struct folio for entry and addr, after queueing swapin.

 *

 * Primitive swap readahead code. We simply read an aligned block of

 * (1 << page_cluster) entries in the swap area. This method is chosen
@@ -631,7 +631,7 @@ static unsigned long swapin_nr_pages(unsigned long offset) 
 * are used for every page of the readahead: neighbouring pages on swap

 * are fairly likely to have been swapped out from the same node.

 */

struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,

struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,

				    struct mempolicy *mpol, pgoff_t ilx)

{

	struct folio *folio;
@@ -683,7 +683,7 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, 
	if (unlikely(page_allocated))

		swap_read_folio(folio, false, NULL);

	zswap_folio_swapin(folio);

	return folio_file_page(folio, swp_offset(entry));

	return folio;

}



int init_swap_address_space(unsigned int type, unsigned long nr_pages)
@@ -787,7 +787,7 @@ static void swap_ra_info(struct vm_fault *vmf, 
 * @targ_ilx: NUMA interleave index, for use only when MPOL_INTERLEAVE

 * @vmf: fault information

 *

 * Returns the struct page for entry and addr, after queueing swapin.

 * Returns the struct folio for entry and addr, after queueing swapin.

 *

 * Primitive swap readahead code. We simply read in a few pages whose

 * virtual addresses are around the fault address in the same vma.
@@ -795,9 +795,8 @@ static void swap_ra_info(struct vm_fault *vmf, 
 * Caller must hold read mmap_lock if vmf->vma is not NULL.

 *

 */

static struct page *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask,

				       struct mempolicy *mpol, pgoff_t targ_ilx,

				       struct vm_fault *vmf)

static struct folio *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask,

		struct mempolicy *mpol, pgoff_t targ_ilx, struct vm_fault *vmf)

{

	struct blk_plug plug;

	struct swap_iocb *splug = NULL;
@@ -859,7 +858,7 @@ static struct page *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask, 
	if (unlikely(page_allocated))

		swap_read_folio(folio, false, NULL);

	zswap_folio_swapin(folio);

	return folio_file_page(folio, swp_offset(entry));

	return folio;

}



/**
@@ -879,14 +878,17 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask, 
{

	struct mempolicy *mpol;

	pgoff_t ilx;

	struct page *page;

	struct folio *folio;



	mpol = get_vma_policy(vmf->vma, vmf->address, 0, &ilx);

	page = swap_use_vma_readahead() ?

	folio = swap_use_vma_readahead() ?

		swap_vma_readahead(entry, gfp_mask, mpol, ilx, vmf) :

		swap_cluster_readahead(entry, gfp_mask, mpol, ilx);

	mpol_cond_put(mpol);

	return page;



	if (!folio)

		return NULL;

	return folio_file_page(folio, swp_offset(entry));

}



#ifdef CONFIG_SYSFS