From patchwork Tue Mar 17 10:03:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 11442381 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 41E09913 for ; Tue, 17 Mar 2020 10:04:05 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F31D12071C for ; Tue, 17 Mar 2020 10:04:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F31D12071C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 16FD76B0005; Tue, 17 Mar 2020 06:04:04 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 1201E6B0006; Tue, 17 Mar 2020 06:04:04 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 036426B0007; Tue, 17 Mar 2020 06:04:03 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0026.hostedemail.com [216.40.44.26]) by kanga.kvack.org (Postfix) with ESMTP id DFE386B0005 for ; Tue, 17 Mar 2020 06:04:03 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id A94FC4DBC for ; Tue, 17 Mar 2020 10:04:03 +0000 (UTC) X-FDA: 76604418366.30.trade38_406cb918e5e0c X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,ying.huang@intel.com,,RULES_HIT:30003:30012:30045:30054:30056:30064:30070:30075,0,RBL:192.55.52.151:@intel.com:.lbl8.mailshell.net-64.95.201.95 62.18.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:ft,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: trade38_406cb918e5e0c X-Filterd-Recvd-Size: 17832 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Tue, 17 Mar 2020 10:04:02 +0000 (UTC) IronPort-SDR: QzpKv7DPKbR+m36oYTfttSZuz29BKZus2y4EG/htV/rXXus1XuUobeDVPfORdpA2nc4p4GTkK3 Y9Ko7XWAijXA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Mar 2020 03:04:00 -0700 IronPort-SDR: WKZvkw3gliFD7d9xSYhUiHEuWtET+YXZML7qNTSamfPTCqA6nYJkLCdGkW3JFSOzcFwsXLQtui AgJBraXw/g3A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,564,1574150400"; d="scan'208";a="445443078" Received: from yhuang-dev.sh.intel.com ([10.239.159.23]) by fmsmga006.fm.intel.com with ESMTP; 17 Mar 2020 03:03:55 -0700 From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , David Hildenbrand , Johannes Weiner , David Rientjes , Michal Hocko , Pankaj Gupta , Vlastimil Babka , Dave Hansen , Mel Gorman , Minchan Kim , Hugh Dickins , Rik van Riel Subject: [PATCH -V3] mm: Code cleanup for MADV_FREE Date: Tue, 17 Mar 2020 18:03:42 +0800 Message-Id: <20200317100342.2730705-1-ying.huang@intel.com> X-Mailer: git-send-email 2.25.0 MIME-Version: 1.0 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: From: Huang Ying Some comments for MADV_FREE is revised and added to help people understand the MADV_FREE code, especially the page flag, PG_swapbacked. This makes page_is_file_cache() isn't consistent with its comments. So the function is renamed to page_is_file_lru() to make them consistent again. All these are put in one patch as one logical change. Signed-off-by: "Huang, Ying" Suggested-by: David Hildenbrand Suggested-and-acked-by: Johannes Weiner Suggested-and-acked-by: David Rientjes Acked-by: Michal Hocko Acked-by: Pankaj Gupta Acked-by: Vlastimil Babka Cc: Dave Hansen Cc: Mel Gorman Cc: Minchan Kim Cc: Hugh Dickins Cc: Rik van Riel --- Changelog: v3: - Revised comments of page_is_file_lru(), Thanks Vlastimil! v2: - Revised comments of PG_swapbacked, Thanks Michal! --- include/linux/mm_inline.h | 15 ++++++++------- include/linux/page-flags.h | 5 +++++ include/trace/events/vmscan.h | 2 +- mm/compaction.c | 2 +- mm/gup.c | 2 +- mm/khugepaged.c | 4 ++-- mm/memory-failure.c | 2 +- mm/memory_hotplug.c | 2 +- mm/mempolicy.c | 2 +- mm/migrate.c | 16 ++++++++-------- mm/mprotect.c | 2 +- mm/swap.c | 16 ++++++++-------- mm/vmscan.c | 12 ++++++------ 13 files changed, 44 insertions(+), 38 deletions(-) diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h index 6f2fef7b0784..219bef41d87c 100644 --- a/include/linux/mm_inline.h +++ b/include/linux/mm_inline.h @@ -6,19 +6,20 @@ #include /** - * page_is_file_cache - should the page be on a file LRU or anon LRU? + * page_is_file_lru - should the page be on a file LRU or anon LRU? * @page: the page to test * - * Returns 1 if @page is page cache page backed by a regular filesystem, - * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed. - * Used by functions that manipulate the LRU lists, to sort a page - * onto the right LRU list. + * Returns 1 if @page is a regular filesystem backed page cache page or a lazily + * freed anonymous page (e.g. via MADV_FREE). Returns 0 if @page is a normal + * anonymous page, a tmpfs page or otherwise ram or swap backed page. Used by + * functions that manipulate the LRU lists, to sort a page onto the right LRU + * list. * * We would like to get this info without a page flag, but the state * needs to survive until the page is last deleted from the LRU, which * could be as far down as __page_cache_release. */ -static inline int page_is_file_cache(struct page *page) +static inline int page_is_file_lru(struct page *page) { return !PageSwapBacked(page); } @@ -75,7 +76,7 @@ static __always_inline void del_page_from_lru_list(struct page *page, */ static inline enum lru_list page_lru_base_type(struct page *page) { - if (page_is_file_cache(page)) + if (page_is_file_lru(page)) return LRU_INACTIVE_FILE; return LRU_INACTIVE_ANON; } diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index d4771b1a1232..222f6f7b2bb3 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -63,6 +63,11 @@ * page_waitqueue(page) is a wait queue of all tasks waiting for the page * to become unlocked. * + * PG_swapbacked is set when a page uses swap as a backing storage. This are + * usually PageAnon or shmem pages but please note that even anonymous pages + * might lose their PG_swapbacked flag when they simply can be dropped (e.g. as + * a result of MADV_FREE). + * * PG_uptodate tells whether the page's contents is valid. When a read * completes, the page becomes uptodate, unless a disk I/O error happened. * diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h index a5ab2973e8dc..74bb594ccb25 100644 --- a/include/trace/events/vmscan.h +++ b/include/trace/events/vmscan.h @@ -323,7 +323,7 @@ TRACE_EVENT(mm_vmscan_writepage, TP_fast_assign( __entry->pfn = page_to_pfn(page); __entry->reclaim_flags = trace_reclaim_flags( - page_is_file_cache(page)); + page_is_file_lru(page)); ), TP_printk("page=%p pfn=%lu flags=%s", diff --git a/mm/compaction.c b/mm/compaction.c index 827d8a2b3164..e8c84c6d4267 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -990,7 +990,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, /* Successfully isolated */ del_page_from_lru_list(page, lruvec, page_lru(page)); mod_node_page_state(page_pgdat(page), - NR_ISOLATED_ANON + page_is_file_cache(page), + NR_ISOLATED_ANON + page_is_file_lru(page), hpage_nr_pages(page)); isolate_success: diff --git a/mm/gup.c b/mm/gup.c index e8aaa40c35ea..411cb09b4be3 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1691,7 +1691,7 @@ static long check_and_migrate_cma_pages(struct task_struct *tsk, list_add_tail(&head->lru, &cma_page_list); mod_node_page_state(page_pgdat(head), NR_ISOLATED_ANON + - page_is_file_cache(head), + page_is_file_lru(head), hpage_nr_pages(head)); } } diff --git a/mm/khugepaged.c b/mm/khugepaged.c index d0ce22fb58d2..e8709e19beea 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -514,7 +514,7 @@ void __khugepaged_exit(struct mm_struct *mm) static void release_pte_page(struct page *page) { - dec_node_page_state(page, NR_ISOLATED_ANON + page_is_file_cache(page)); + dec_node_page_state(page, NR_ISOLATED_ANON + page_is_file_lru(page)); unlock_page(page); putback_lru_page(page); } @@ -614,7 +614,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, goto out; } inc_node_page_state(page, - NR_ISOLATED_ANON + page_is_file_cache(page)); + NR_ISOLATED_ANON + page_is_file_lru(page)); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageLRU(page), page); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 1c961cd26c0b..a96364be8ab4 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1810,7 +1810,7 @@ static int __soft_offline_page(struct page *page, int flags) */ if (!__PageMovable(page)) inc_node_page_state(page, NR_ISOLATED_ANON + - page_is_file_cache(page)); + page_is_file_lru(page)); list_add(&page->lru, &pagelist); ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL, MIGRATE_SYNC, MR_MEMORY_FAILURE); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 8bdf484241de..e3b2074ef30c 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1324,7 +1324,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) list_add_tail(&page->lru, &source); if (!__PageMovable(page)) inc_node_page_state(page, NR_ISOLATED_ANON + - page_is_file_cache(page)); + page_is_file_lru(page)); } else { pr_warn("failed to isolate pfn %lx\n", pfn); diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 0c6fbee1ea5a..2c41923892f7 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1048,7 +1048,7 @@ static int migrate_page_add(struct page *page, struct list_head *pagelist, if (!isolate_lru_page(head)) { list_add_tail(&head->lru, pagelist); mod_node_page_state(page_pgdat(head), - NR_ISOLATED_ANON + page_is_file_cache(head), + NR_ISOLATED_ANON + page_is_file_lru(head), hpage_nr_pages(head)); } else if (flags & MPOL_MF_STRICT) { /* diff --git a/mm/migrate.c b/mm/migrate.c index 8f62089126ad..de23507f5c68 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -193,7 +193,7 @@ void putback_movable_pages(struct list_head *l) put_page(page); } else { mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + - page_is_file_cache(page), -hpage_nr_pages(page)); + page_is_file_lru(page), -hpage_nr_pages(page)); putback_lru_page(page); } } @@ -1223,7 +1223,7 @@ static ICE_noinline int unmap_and_move(new_page_t get_new_page, */ if (likely(!__PageMovable(page))) mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + - page_is_file_cache(page), -hpage_nr_pages(page)); + page_is_file_lru(page), -hpage_nr_pages(page)); } /* @@ -1595,7 +1595,7 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, err = 1; list_add_tail(&head->lru, pagelist); mod_node_page_state(page_pgdat(head), - NR_ISOLATED_ANON + page_is_file_cache(head), + NR_ISOLATED_ANON + page_is_file_lru(head), hpage_nr_pages(head)); } out_putpage: @@ -1958,7 +1958,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) return 0; } - page_lru = page_is_file_cache(page); + page_lru = page_is_file_lru(page); mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_lru, hpage_nr_pages(page)); @@ -1994,7 +1994,7 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, * Don't migrate file pages that are mapped in multiple processes * with execute permissions as they are probably shared libraries. */ - if (page_mapcount(page) != 1 && page_is_file_cache(page) && + if (page_mapcount(page) != 1 && page_is_file_lru(page) && (vma->vm_flags & VM_EXEC)) goto out; @@ -2002,7 +2002,7 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, * Also do not migrate dirty pages as not all filesystems can move * dirty pages in MIGRATE_ASYNC mode which is a waste of cycles. */ - if (page_is_file_cache(page) && PageDirty(page)) + if (page_is_file_lru(page) && PageDirty(page)) goto out; isolated = numamigrate_isolate_page(pgdat, page); @@ -2017,7 +2017,7 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, if (!list_empty(&migratepages)) { list_del(&page->lru); dec_node_page_state(page, NR_ISOLATED_ANON + - page_is_file_cache(page)); + page_is_file_lru(page)); putback_lru_page(page); } isolated = 0; @@ -2047,7 +2047,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm, pg_data_t *pgdat = NODE_DATA(node); int isolated = 0; struct page *new_page = NULL; - int page_lru = page_is_file_cache(page); + int page_lru = page_is_file_lru(page); unsigned long start = address & HPAGE_PMD_MASK; new_page = alloc_pages_node(node, diff --git a/mm/mprotect.c b/mm/mprotect.c index 4d30c4b549e1..494192ca954b 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -102,7 +102,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, * it cannot move them all from MIGRATE_ASYNC * context. */ - if (page_is_file_cache(page) && PageDirty(page)) + if (page_is_file_lru(page) && PageDirty(page)) continue; /* diff --git a/mm/swap.c b/mm/swap.c index 6a8be910b14d..f70e8b0b7319 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -276,7 +276,7 @@ static void __activate_page(struct page *page, struct lruvec *lruvec, void *arg) { if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) { - int file = page_is_file_cache(page); + int file = page_is_file_lru(page); int lru = page_lru_base_type(page); del_page_from_lru_list(page, lruvec, lru); @@ -394,7 +394,7 @@ void mark_page_accessed(struct page *page) else __lru_cache_activate_page(page); ClearPageReferenced(page); - if (page_is_file_cache(page)) + if (page_is_file_lru(page)) workingset_activation(page); } if (page_is_idle(page)) @@ -515,7 +515,7 @@ static void lru_deactivate_file_fn(struct page *page, struct lruvec *lruvec, return; active = PageActive(page); - file = page_is_file_cache(page); + file = page_is_file_lru(page); lru = page_lru_base_type(page); del_page_from_lru_list(page, lruvec, lru + active); @@ -548,7 +548,7 @@ static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec, void *arg) { if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) { - int file = page_is_file_cache(page); + int file = page_is_file_lru(page); int lru = page_lru_base_type(page); del_page_from_lru_list(page, lruvec, lru + LRU_ACTIVE); @@ -573,9 +573,9 @@ static void lru_lazyfree_fn(struct page *page, struct lruvec *lruvec, ClearPageActive(page); ClearPageReferenced(page); /* - * lazyfree pages are clean anonymous pages. They have - * SwapBacked flag cleared to distinguish normal anonymous - * pages + * Lazyfree pages are clean anonymous pages. They have + * PG_swapbacked flag cleared, to distinguish them from normal + * anonymous pages */ ClearPageSwapBacked(page); add_page_to_lru_list(page, lruvec, LRU_INACTIVE_FILE); @@ -963,7 +963,7 @@ static void __pagevec_lru_add_fn(struct page *page, struct lruvec *lruvec, if (page_evictable(page)) { lru = page_lru(page); - update_page_reclaim_stat(lruvec, page_is_file_cache(page), + update_page_reclaim_stat(lruvec, page_is_file_lru(page), PageActive(page)); if (was_unevictable) count_vm_event(UNEVICTABLE_PGRESCUED); diff --git a/mm/vmscan.c b/mm/vmscan.c index d9fb680884b8..d290a268dd68 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -919,7 +919,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, * exceptional entries and shadow exceptional entries in the * same address_space. */ - if (reclaimed && page_is_file_cache(page) && + if (reclaimed && page_is_file_lru(page) && !mapping_exiting(mapping) && !dax_mapping(mapping)) shadow = workingset_eviction(page, target_memcg); __delete_from_page_cache(page, shadow); @@ -1043,7 +1043,7 @@ static void page_check_dirty_writeback(struct page *page, * Anonymous pages are not handled by flushers and must be written * from reclaim context. Do not stall reclaim based on them */ - if (!page_is_file_cache(page) || + if (!page_is_file_lru(page) || (PageAnon(page) && !PageSwapBacked(page))) { *dirty = false; *writeback = false; @@ -1316,7 +1316,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, * the rest of the LRU for clean pages and see * the same dirty pages again (PageReclaim). */ - if (page_is_file_cache(page) && + if (page_is_file_lru(page) && (!current_is_kswapd() || !PageReclaim(page) || !test_bit(PGDAT_DIRTY, &pgdat->flags))) { /* @@ -1460,7 +1460,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, try_to_free_swap(page); VM_BUG_ON_PAGE(PageActive(page), page); if (!PageMlocked(page)) { - int type = page_is_file_cache(page); + int type = page_is_file_lru(page); SetPageActive(page); stat->nr_activate[type] += nr_pages; count_memcg_page_event(page, PGACTIVATE); @@ -1498,7 +1498,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, LIST_HEAD(clean_pages); list_for_each_entry_safe(page, next, page_list, lru) { - if (page_is_file_cache(page) && !PageDirty(page) && + if (page_is_file_lru(page) && !PageDirty(page) && !__PageMovable(page) && !PageUnevictable(page)) { ClearPageActive(page); list_move(&page->lru, &clean_pages); @@ -2054,7 +2054,7 @@ static void shrink_active_list(unsigned long nr_to_scan, * IO, plus JVM can create lots of anon VM_EXEC pages, * so we ignore them here. */ - if ((vm_flags & VM_EXEC) && page_is_file_cache(page)) { + if ((vm_flags & VM_EXEC) && page_is_file_lru(page)) { list_add(&page->lru, &l_active); continue; }