From 1baec203b77cafa24610b5c9ae7a2aa380d74ef6 Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Sat, 25 Jun 2022 17:28:16 +0800 Subject: mm/khugepaged: try to free transhuge swapcache when possible Transhuge swapcaches won't be freed in __collapse_huge_page_copy(). It's because release_pte_page() is not called for these pages and thus free_page_and_swap_cache can't grab the page lock. These pages won't be freed from swap cache even if we are the only user 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/20220625092816.4856-8-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Cc: Alistair Popple Cc: Andrea Arcangeli Cc: David Hildenbrand Cc: David Howells Cc: Matthew Wilcox (Oracle) Cc: NeilBrown Cc: Peter Xu Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Yang Shi Cc: Zach O'Keefe Signed-off-by: Andrew Morton --- mm/khugepaged.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'mm/khugepaged.c') diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 08e885f28def..01e0d6336754 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -755,7 +755,12 @@ static void __collapse_huge_page_copy(pte_t *pte, struct page *page, list_for_each_entry_safe(src_page, tmp, compound_pagelist, lru) { list_del(&src_page->lru); - release_pte_page(src_page); + mod_node_page_state(page_pgdat(src_page), + NR_ISOLATED_ANON + page_is_file_lru(src_page), + -compound_nr(src_page)); + unlock_page(src_page); + free_swap_cache(src_page); + putback_lru_page(src_page); } } -- cgit v1.2.3