From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F2CAC433E0 for ; Wed, 24 Feb 2021 20:09:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3912F64F0E for ; Wed, 24 Feb 2021 20:09:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235182AbhBXUJV (ORCPT ); Wed, 24 Feb 2021 15:09:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:59764 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235372AbhBXUIr (ORCPT ); Wed, 24 Feb 2021 15:08:47 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8176464F1D; Wed, 24 Feb 2021 20:08:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1614197310; bh=Y0+LHY/h97swDRw6Vb+0jE85/g2oXqbQ5XEZhkLKnok=; h=Date:From:To:Subject:In-Reply-To:From; b=If8bOR32/MNwHofCUdN07MzYq8bIuxZKKqY6mCUA9F9ots/zDe4zD+wzSASCr2VvI PckfHxCr7M+LQoMI9crhuul9mhgBGI52IWKAa8MBiXO8g14mqSvBrHQT3QVcrpd4d6 DnZvV9EWpq+UGmGAZi+WPupcRWR17Fhv7zkghlTc= Date: Wed, 24 Feb 2021 12:08:28 -0800 From: Andrew Morton To: akpm@linux-foundation.org, alex.shi@linux.alibaba.com, guro@fb.com, hannes@cmpxchg.org, hughd@google.com, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vbabka@suse.cz, vdavydov.dev@gmail.com, willy@infradead.org, yuzhao@google.com Subject: [patch 140/173] mm: add __clear_page_lru_flags() to replace page_off_lru() Message-ID: <20210224200828.TIcm2MbA8%akpm@linux-foundation.org> In-Reply-To: <20210224115824.1e289a6895087f10c41dd8d6@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Yu Zhao Subject: mm: add __clear_page_lru_flags() to replace page_off_lru() Similar to page_off_lru(), the new function does non-atomic clearing of PageLRU() in addition to PageActive() and PageUnevictable(), on a page that has no references left. If PageActive() and PageUnevictable() are both set, refuse to clear either and leave them to bad_page(). This is a behavior change that is meant to help debug. Link: https://lore.kernel.org/linux-mm/20201207220949.830352-7-yuzhao@google.com/ Link: https://lkml.kernel.org/r/20210122220600.906146-7-yuzhao@google.com Signed-off-by: Yu Zhao Cc: Alex Shi Cc: Hugh Dickins Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Michal Hocko Cc: Roman Gushchin Cc: Vladimir Davydov Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/mm_inline.h | 28 ++++++++++------------------ mm/swap.c | 6 ++---- mm/vmscan.c | 3 +-- 3 files changed, 13 insertions(+), 24 deletions(-) --- a/include/linux/mm_inline.h~mm-add-__clear_page_lru_flags-to-replace-page_off_lru +++ a/include/linux/mm_inline.h @@ -61,27 +61,19 @@ static inline enum lru_list page_lru_bas } /** - * page_off_lru - which LRU list was page on? clearing its lru flags. - * @page: the page to test - * - * Returns the LRU list a page was on, as an index into the array of LRU - * lists; and clears its Unevictable or Active flags, ready for freeing. + * __clear_page_lru_flags - clear page lru flags before releasing a page + * @page: the page that was on lru and now has a zero reference */ -static __always_inline enum lru_list page_off_lru(struct page *page) +static __always_inline void __clear_page_lru_flags(struct page *page) { - enum lru_list lru; + __ClearPageLRU(page); - if (PageUnevictable(page)) { - __ClearPageUnevictable(page); - lru = LRU_UNEVICTABLE; - } else { - lru = page_lru_base_type(page); - if (PageActive(page)) { - __ClearPageActive(page); - lru += LRU_ACTIVE; - } - } - return lru; + /* this shouldn't happen, so leave the flags to bad_page() */ + if (PageActive(page) && PageUnevictable(page)) + return; + + __ClearPageActive(page); + __ClearPageUnevictable(page); } /** --- a/mm/swap.c~mm-add-__clear_page_lru_flags-to-replace-page_off_lru +++ a/mm/swap.c @@ -84,9 +84,8 @@ static void __page_cache_release(struct lruvec = lock_page_lruvec_irqsave(page, &flags); VM_BUG_ON_PAGE(!PageLRU(page), page); - __ClearPageLRU(page); del_page_from_lru_list(page, lruvec); - page_off_lru(page); + __clear_page_lru_flags(page); unlock_page_lruvec_irqrestore(lruvec, flags); } __ClearPageWaiters(page); @@ -911,9 +910,8 @@ void release_pages(struct page **pages, lock_batch = 0; VM_BUG_ON_PAGE(!PageLRU(page), page); - __ClearPageLRU(page); del_page_from_lru_list(page, lruvec); - page_off_lru(page); + __clear_page_lru_flags(page); } __ClearPageWaiters(page); --- a/mm/vmscan.c~mm-add-__clear_page_lru_flags-to-replace-page_off_lru +++ a/mm/vmscan.c @@ -1849,8 +1849,7 @@ static unsigned noinline_for_stack move_ SetPageLRU(page); if (unlikely(put_page_testzero(page))) { - __ClearPageLRU(page); - __ClearPageActive(page); + __clear_page_lru_flags(page); if (unlikely(PageCompound(page))) { spin_unlock_irq(&lruvec->lru_lock); _