The patch titled
Subject: mm: return the folio from swapin_readahead
has been added to the -mm mm-unstable branch. Its filename is
mm-return-the-folio-from-swapin_readahead.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-return-the-folio-from-swapin_readahead.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: return the folio from swapin_readahead
Date: Wed, 7 Aug 2024 20:37:32 +0100
The unuse_pte_range() caller only wants the folio while do_swap_page()
wants both the page and the folio. Since do_swap_page() already has logic
for handling both the folio and the page, move the folio-to-page logic
there. This also lets us allocate larger folios in the SWP_SYNCHRONOUS_IO
path in future.
Link: https://lkml.kernel.org/r/20240807193734.1865400-1-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory.c | 6 ++----
mm/swap.h | 6 +++---
mm/swap_state.c | 8 +++-----
mm/swapfile.c | 5 +----
4 files changed, 9 insertions(+), 16 deletions(-)
--- a/mm/memory.c~mm-return-the-folio-from-swapin_readahead
+++ a/mm/memory.c
@@ -4223,7 +4223,6 @@ vm_fault_t do_swap_page(struct vm_fault
__swap_count(entry) == 1) {
/* skip swapcache */
folio = alloc_swap_folio(vmf);
- page = &folio->page;
if (folio) {
__folio_set_locked(folio);
__folio_set_swapbacked(folio);
@@ -4265,10 +4264,8 @@ vm_fault_t do_swap_page(struct vm_fault
folio->private = NULL;
}
} else {
- page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
+ folio = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
vmf);
- if (page)
- folio = page_folio(page);
swapcache = folio;
}
@@ -4289,6 +4286,7 @@ vm_fault_t do_swap_page(struct vm_fault
ret = VM_FAULT_MAJOR;
count_vm_event(PGMAJFAULT);
count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
+ page = folio_file_page(folio, swp_offset(entry));
} else if (PageHWPoison(page)) {
/*
* hwpoisoned dirty swapcache pages are kept for killing
--- a/mm/swapfile.c~mm-return-the-folio-from-swapin_readahead
+++ a/mm/swapfile.c
@@ -2124,7 +2124,6 @@ static int unuse_pte_range(struct vm_are
folio = swap_cache_get_folio(entry, vma, addr);
if (!folio) {
- struct page *page;
struct vm_fault vmf = {
.vma = vma,
.address = addr,
@@ -2132,10 +2131,8 @@ static int unuse_pte_range(struct vm_are
.pmd = pmd,
};
- page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
+ folio = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
&vmf);
- if (page)
- folio = page_folio(page);
}
if (!folio) {
swp_count = READ_ONCE(si->swap_map[offset]);
--- a/mm/swap.h~mm-return-the-folio-from-swapin_readahead
+++ a/mm/swap.h
@@ -73,8 +73,8 @@ struct folio *__read_swap_cache_async(sw
bool skip_if_exists);
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);
+struct folio *swapin_readahead(swp_entry_t entry, gfp_t flag,
+ struct vm_fault *vmf);
static inline unsigned int folio_swap_flags(struct folio *folio)
{
@@ -109,7 +109,7 @@ static inline struct folio *swap_cluster
return NULL;
}
-static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
+static inline struct folio *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
struct vm_fault *vmf)
{
return NULL;
--- a/mm/swap_state.c~mm-return-the-folio-from-swapin_readahead
+++ a/mm/swap_state.c
@@ -863,13 +863,13 @@ skip:
* @gfp_mask: memory allocation flags
* @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.
*
* It's a main entry function for swap readahead. By the configuration,
* it will read ahead blocks by cluster-based(ie, physical disk based)
* or vma-based(ie, virtual address based on faulty address) readahead.
*/
-struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
+struct folio *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
struct vm_fault *vmf)
{
struct mempolicy *mpol;
@@ -882,9 +882,7 @@ struct page *swapin_readahead(swp_entry_
swap_cluster_readahead(entry, gfp_mask, mpol, ilx);
mpol_cond_put(mpol);
- if (!folio)
- return NULL;
- return folio_file_page(folio, swp_offset(entry));
+ return folio;
}
#ifdef CONFIG_SYSFS
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
fs-remove-calls-to-set-and-clear-the-folio-error-flag.patch
mm-remove-pg_error.patch
mm-return-the-folio-from-swapin_readahead.patch
