+ mm-huge_memory-try-to-free-subpage-in-swapcache-when-possible.patch added to mm-unstable branch

+ mm-huge_memory-try-to-free-subpage-in-swapcache-when-possible.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/huge_memory: try to free subpage in swapcache when possible
has been added to the -mm mm-unstable branch.  Its filename is
     mm-huge_memory-try-to-free-subpage-in-swapcache-when-possible.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-huge_memory-try-to-free-subpage-in-swapcache-when-possible.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: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/huge_memory: try to free subpage in swapcache when possible
Date: Mon, 4 Jul 2022 21:21:56 +0800

Subpages in swapcache won't be freed even if it is the last user of the
page until next time reclaim. It shouldn't hurt indeed, but we could try
to free these pages to save more memory for system.

Link: https://lkml.kernel.org/r/20220704132201.14611-12-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/huge_memory.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/huge_memory.c~mm-huge_memory-try-to-free-subpage-in-swapcache-when-possible
+++ a/mm/huge_memory.c
@@ -2638,7 +2638,7 @@ static void __split_huge_page(struct pag
 		 * requires taking the lru_lock so we do the put_page
 		 * of the tail pages after the split is complete.
 		 */
-		put_page(subpage);
+		free_page_and_swap_cache(subpage);
 	}
 }
 
_

Patches currently in -mm which might be from linmiaohe@huawei.com are

mm-page_alloc-minor-clean-up-for-memmap_init_compound.patch
mm-mmapc-fix-missing-call-to-vm_unacct_memory-in-mmap_region.patch
filemap-minor-cleanup-for-filemap_write_and_wait_range.patch
mm-huge_memory-use-flush_pmd_tlb_range-in-move_huge_pmd.patch
mm-huge_memory-access-vm_page_prot-with-read_once-in-remove_migration_pmd.patch
mm-huge_memory-fix-comment-of-__pud_trans_huge_lock.patch
mm-huge_memory-use-helper-touch_pud-in-huge_pud_set_accessed.patch
mm-huge_memory-use-helper-touch_pmd-in-huge_pmd_set_accessed.patch
mm-huge_memory-rename-mmun_start-to-haddr-in-remove_migration_pmd.patch
mm-huge_memory-use-helper-function-vma_lookup-in-split_huge_pages_pid.patch
mm-huge_memory-use-helper-macro-__attr_rw.patch
mm-huge_memory-fix-comment-in-zap_huge_pud.patch
mm-huge_memory-check-pmd_present-first-in-is_huge_zero_pmd.patch
mm-huge_memory-try-to-free-subpage-in-swapcache-when-possible.patch
mm-huge_memory-minor-cleanup-for-split_huge_pages_all.patch
mm-huge_memory-fix-comment-of-page_deferred_list.patch
mm-huge_memory-correct-comment-of-prep_transhuge_page.patch
mm-huge_memory-comment-the-subtly-logic-in-__split_huge_pmd.patch
mm-huge_memory-use-helper-macro-is_err_or_null-in-split_huge_pages_pid.patch