From patchwork Sat Jun 25 09:28:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12895284 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id DBA6AC43334 for ; Sat, 25 Jun 2022 09:28:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id F03CD8E0299; Sat, 25 Jun 2022 05:28:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E171D8E0296; Sat, 25 Jun 2022 05:28:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C6A5D8E0299; Sat, 25 Jun 2022 05:28:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id B745B8E0296 for ; Sat, 25 Jun 2022 05:28:26 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 95BFC33E68 for ; Sat, 25 Jun 2022 09:28:26 +0000 (UTC) X-FDA: 79616232612.23.101EA78 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf13.hostedemail.com (Postfix) with ESMTP id CBA1620014 for ; Sat, 25 Jun 2022 09:28:25 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4LVTC16wT6zkWPb; Sat, 25 Jun 2022 17:26:37 +0800 (CST) Received: from huawei.com (10.175.124.27) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Sat, 25 Jun 2022 17:28:22 +0800 From: Miaohe Lin To: CC: , , , , , , , , , , , , , Subject: [PATCH v2 7/7] mm/khugepaged: try to free transhuge swapcache when possible Date: Sat, 25 Jun 2022 17:28:16 +0800 Message-ID: <20220625092816.4856-8-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220625092816.4856-1-linmiaohe@huawei.com> References: <20220625092816.4856-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656149306; a=rsa-sha256; cv=none; b=rlhsreuQOsDOQU4DbHOsVygWizACMRMi0y+HjYEs6X6r1OKbiHhfw1nzZJb//2/w9QmgsI B4ZPhpNjm8m4NPCIjdwj3arXRReiw5SXdhVxATExdS0yLvuiLFy6vm/HOwMEeHGVPdFaUC WN7rHj7VagMg3m1ibq1Z2v2xyaRKp3U= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf13.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656149306; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=39GylbJpV191tNrnEOvKlpyCCcfY0x3fZU8t2cHDRzc=; b=Y27X1mcd/1ooQNRGk3Jq34pSDXYZeIFApllus9muDuxEANcwaWHgYDvyVnKtSf6ehdOXNc JwZ2dz0to2geP0LjTGMQ0fHrPg1pWAiP//qnQNa0mZkBTllNs8xbElugWmkFuVXfnqfH/9 hlEf9Nuc0+Wy5gaiui+5U6iUYRN9I4s= X-Rspam-User: X-Stat-Signature: 9ptc6c6rojqdubm6xoang913wf553jcq X-Rspamd-Queue-Id: CBA1620014 Authentication-Results: imf13.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf13.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-Rspamd-Server: rspam03 X-HE-Tag: 1656149305-382171 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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. Signed-off-by: Miaohe Lin --- include/linux/swap.h | 5 +++++ mm/khugepaged.c | 7 ++++++- mm/swap.h | 5 ----- 3 files changed, 11 insertions(+), 6 deletions(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index 8672a7123ccd..ccb83b12b724 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -456,6 +456,7 @@ static inline unsigned long total_swapcache_pages(void) return global_node_page_state(NR_SWAPCACHE); } +extern void free_swap_cache(struct page *page); extern void free_page_and_swap_cache(struct page *); extern void free_pages_and_swap_cache(struct page **, int); /* linux/mm/swapfile.c */ @@ -540,6 +541,10 @@ static inline void put_swap_device(struct swap_info_struct *si) /* used to sanity check ptes in zap_pte_range when CONFIG_SWAP=0 */ #define free_swap_and_cache(e) is_pfn_swap_entry(e) +static inline void free_swap_cache(struct page *page) +{ +} + static inline int add_swap_count_continuation(swp_entry_t swp, gfp_t gfp_mask) { return 0; diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 6cb82a299eb2..cfe231c5958f 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -716,7 +716,12 @@ 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); } } diff --git a/mm/swap.h b/mm/swap.h index fa0816af4712..17936e068c1c 100644 --- a/mm/swap.h +++ b/mm/swap.h @@ -41,7 +41,6 @@ void __delete_from_swap_cache(struct folio *folio, void delete_from_swap_cache(struct folio *folio); void clear_shadow_from_swap_cache(int type, unsigned long begin, unsigned long end); -void free_swap_cache(struct page *page); struct page *lookup_swap_cache(swp_entry_t entry, struct vm_area_struct *vma, unsigned long addr); @@ -81,10 +80,6 @@ static inline struct address_space *swap_address_space(swp_entry_t entry) return NULL; } -static inline void free_swap_cache(struct page *page) -{ -} - static inline void show_swap_cache_info(void) { }