+ swap_state-convert-free_swap_cache-to-use-a-folio.patch added to mm-unstable branch

+ swap_state-convert-free_swap_cache-to-use-a-folio.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: swap_state: convert free_swap_cache() to use a folio
has been added to the -mm mm-unstable branch.  Its filename is
     swap_state-convert-free_swap_cache-to-use-a-folio.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/swap_state-convert-free_swap_cache-to-use-a-folio.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@infradead.org>
Subject: swap_state: convert free_swap_cache() to use a folio
Date: Fri, 2 Sep 2022 20:46:35 +0100

Saves several calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-40-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swap_state.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

--- a/mm/swap_state.c~swap_state-convert-free_swap_cache-to-use-a-folio
+++ a/mm/swap_state.c
@@ -272,16 +272,19 @@ void clear_shadow_from_swap_cache(int ty
 /* 
  * If we are the only user, then try to free up the swap cache. 
  * 
- * Its ok to check for PageSwapCache without the page lock
+ * Its ok to check the swapcache flag without the folio lock
  * here because we are going to recheck again inside
- * try_to_free_swap() _with_ the lock.
+ * folio_free_swap() _with_ the lock.
  * 					- Marcelo
  */
 void free_swap_cache(struct page *page)
 {
-	if (PageSwapCache(page) && !page_mapped(page) && trylock_page(page)) {
-		try_to_free_swap(page);
-		unlock_page(page);
+	struct folio *folio = page_folio(page);
+
+	if (folio_test_swapcache(folio) && !folio_mapped(folio) &&
+	    folio_trylock(folio)) {
+		folio_free_swap(folio);
+		folio_unlock(folio);
 	}
 }
 
_

Patches currently in -mm which might be from willy@infradead.org are

tools-fix-compilation-after-gfp_typesh-split.patch
mm-fix-vm_bug_on-in-__delete_from_swap_cache.patch
vmscan-check-folio_test_private-not-folio_get_private.patch
support-highmem-pages-in-vmap_pages_range_noflush.patch
mm-add-vma-iterator.patch
mmap-use-the-vma-iterator-in-count_vma_pages_range.patch
proc-remove-vma-rbtree-use-from-nommu.patch
arm64-remove-mmap-linked-list-from-vdso.patch
parisc-remove-mmap-linked-list-from-cache-handling.patch
powerpc-remove-mmap-linked-list-walks.patch
s390-remove-vma-linked-list-walks.patch
x86-remove-vma-linked-list-walks.patch
xtensa-remove-vma-linked-list-walks.patch
cxl-remove-vma-linked-list-walk.patch
optee-remove-vma-linked-list-walk.patch
um-remove-vma-linked-list-walk.patch
coredump-remove-vma-linked-list-walk.patch
exec-use-vma-iterator-instead-of-linked-list.patch
fs-proc-task_mmu-stop-using-linked-list-and-highest_vm_end.patch
acct-use-vma-iterator-instead-of-linked-list.patch
perf-use-vma-iterator.patch
sched-use-maple-tree-iterator-to-walk-vmas.patch
fork-use-vma-iterator.patch
mm-khugepaged-stop-using-vma-linked-list.patch
mm-ksm-use-vma-iterators-instead-of-vma-linked-list.patch
mm-mlock-use-vma-iterator-and-maple-state-instead-of-vma-linked-list.patch
mm-pagewalk-use-vma_find-instead-of-vma-linked-list.patch
i915-use-the-vma-iterator.patch
nommu-remove-uses-of-vma-linked-list.patch
mm-vmscan-fix-a-lot-of-comments.patch
mm-add-the-first-tail-page-to-struct-folio.patch
mm-reimplement-folio_order-and-folio_nr_pages.patch
mm-add-split_folio.patch
mm-add-folio_add_lru_vma.patch
shmem-convert-shmem_writepage-to-use-a-folio-throughout.patch
shmem-convert-shmem_delete_from_page_cache-to-take-a-folio.patch
shmem-convert-shmem_replace_page-to-use-folios-throughout.patch
mm-swapfile-remove-page_swapcount.patch
mm-swapfile-convert-try_to_free_swap-to-folio_free_swap.patch
mm-swap-convert-__read_swap_cache_async-to-use-a-folio.patch
mm-swap-convert-add_to_swap_cache-to-take-a-folio.patch
mm-swap-convert-put_swap_page-to-put_swap_folio.patch
mm-convert-do_swap_page-to-use-a-folio.patch
mm-convert-do_swap_pages-swapcache-variable-to-a-folio.patch
memcg-convert-mem_cgroup_swapin_charge_page-to-mem_cgroup_swapin_charge_folio.patch
shmem-convert-shmem_mfill_atomic_pte-to-use-a-folio.patch
shmem-convert-shmem_replace_page-to-shmem_replace_folio.patch
swap-add-swap_cache_get_folio.patch
shmem-eliminate-struct-page-from-shmem_swapin_folio.patch
shmem-convert-shmem_getpage_gfp-to-shmem_get_folio_gfp.patch
shmem-convert-shmem_fault-to-use-shmem_get_folio_gfp.patch
shmem-convert-shmem_read_mapping_page_gfp-to-use-shmem_get_folio_gfp.patch
shmem-add-shmem_get_folio.patch
shmem-convert-shmem_get_partial_folio-to-use-shmem_get_folio.patch
shmem-convert-shmem_write_begin-to-use-shmem_get_folio.patch
shmem-convert-shmem_file_read_iter-to-use-shmem_get_folio.patch
shmem-convert-shmem_fallocate-to-use-a-folio.patch
shmem-convert-shmem_symlink-to-use-a-folio.patch
shmem-convert-shmem_get_link-to-use-a-folio.patch
khugepaged-call-shmem_get_folio.patch
userfaultfd-convert-mcontinue_atomic_pte-to-use-a-folio.patch
shmem-remove-shmem_getpage.patch
swapfile-convert-try_to_unuse-to-use-a-folio.patch
swapfile-convert-__try_to_reclaim_swap-to-use-a-folio.patch
swapfile-convert-unuse_pte_range-to-use-a-folio.patch
mm-convert-do_swap_page-to-use-swap_cache_get_folio.patch
mm-remove-lookup_swap_cache.patch
swap_state-convert-free_swap_cache-to-use-a-folio.patch
swap-convert-swap_writepage-to-use-a-folio.patch
mm-convert-do_wp_page-to-use-a-folio.patch
huge_memory-convert-do_huge_pmd_wp_page-to-use-a-folio.patch
madvise-convert-madvise_free_pte_range-to-use-a-folio.patch
uprobes-use-folios-more-widely-in-__replace_page.patch
ksm-use-a-folio-in-replace_page.patch
mm-convert-do_swap_page-to-use-folio_free_swap.patch
memcg-convert-mem_cgroup_swap_full-to-take-a-folio.patch
mm-remove-try_to_free_swap.patch
rmap-convert-page_move_anon_rmap-to-use-a-folio.patch
migrate-convert-__unmap_and_move-to-use-folios.patch
migrate-convert-unmap_and_move_huge_page-to-use-folios.patch
huge_memory-convert-split_huge_page_to_list-to-use-a-folio.patch
huge_memory-convert-unmap_page-to-unmap_folio.patch
mm-convert-page_get_anon_vma-to-folio_get_anon_vma.patch
rmap-remove-page_unlock_anon_vma_read.patch
uprobes-use-new_folio-in-__replace_page.patch
mm-convert-lock_page_or_retry-to-folio_lock_or_retry.patch