From f7f9c00dfafffd7a5a1a5685e2d874c64913e2ed Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Wed, 15 Feb 2023 18:39:35 +0800 Subject: [PATCH] mm: change to return bool for isolate_lru_page() The isolate_lru_page() can only return 0 or -EBUSY, and most users did not care about the negative error of isolate_lru_page(), except one user in add_page_for_migration(). So we can convert the isolate_lru_page() to return a boolean value, which can help to make the code more clear when checking the return value of isolate_lru_page(). Also convert all users' logic of checking the isolation state. No functional changes intended. Link: https://lkml.kernel.org/r/3074c1ab628d9dbf139b33f248a8bc253a3f95f0.1676424378.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang Acked-by: David Hildenbrand Reviewed-by: Matthew Wilcox (Oracle) Acked-by: Linus Torvalds Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton --- mm/folio-compat.c | 12 +++--------- mm/internal.h | 2 +- mm/khugepaged.c | 2 +- mm/memcontrol.c | 4 ++-- mm/memory-failure.c | 4 ++-- mm/memory_hotplug.c | 8 +++++--- mm/migrate.c | 9 ++++++--- mm/migrate_device.c | 2 +- 8 files changed, 21 insertions(+), 22 deletions(-) diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 540373cf904e..cabcd1de9ecb 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -113,17 +113,11 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, } EXPORT_SYMBOL(grab_cache_page_write_begin); -int isolate_lru_page(struct page *page) +bool isolate_lru_page(struct page *page) { - bool ret; - if (WARN_RATELIMIT(PageTail(page), "trying to isolate tail page")) - return -EBUSY; - ret = folio_isolate_lru((struct folio *)page); - if (ret) - return 0; - - return -EBUSY; + return false; + return folio_isolate_lru((struct folio *)page); } void putback_lru_page(struct page *page) diff --git a/mm/internal.h b/mm/internal.h index 8645e8496537..fc01fd092ea5 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -187,7 +187,7 @@ pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr, /* * in mm/vmscan.c: */ -int isolate_lru_page(struct page *page); +bool isolate_lru_page(struct page *page); bool folio_isolate_lru(struct folio *folio); void putback_lru_page(struct page *page); void folio_putback_lru(struct folio *folio); diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 15eebab0fbb5..987281ead49e 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -636,7 +636,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, * Isolate the page to avoid collapsing an hugepage * currently in use by the VM. */ - if (isolate_lru_page(page)) { + if (!isolate_lru_page(page)) { unlock_page(page); result = SCAN_DEL_PAGE_LRU; goto out; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3e3cdb9bed95..25f2465d5a37 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6176,7 +6176,7 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, target_type = get_mctgt_type_thp(vma, addr, *pmd, &target); if (target_type == MC_TARGET_PAGE) { page = target.page; - if (!isolate_lru_page(page)) { + if (isolate_lru_page(page)) { if (!mem_cgroup_move_account(page, true, mc.from, mc.to)) { mc.precharge -= HPAGE_PMD_NR; @@ -6226,7 +6226,7 @@ retry: */ if (PageTransCompound(page)) goto put; - if (!device && isolate_lru_page(page)) + if (!device && !isolate_lru_page(page)) goto put; if (!mem_cgroup_move_account(page, false, mc.from, mc.to)) { diff --git a/mm/memory-failure.c b/mm/memory-failure.c index db85c2d37f70..e504362fdb23 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -846,7 +846,7 @@ static const char * const action_page_types[] = { */ static int delete_from_lru_cache(struct page *p) { - if (!isolate_lru_page(p)) { + if (isolate_lru_page(p)) { /* * Clear sensible page flags, so that the buddy system won't * complain when the page is unpoison-and-freed. @@ -2513,7 +2513,7 @@ static bool isolate_page(struct page *page, struct list_head *pagelist) bool lru = !__PageMovable(page); if (lru) - isolated = !isolate_lru_page(page); + isolated = isolate_lru_page(page); else isolated = !isolate_movable_page(page, ISOLATE_UNEVICTABLE); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index a1e8c3e9ab08..5fc2dcf4e3ab 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1632,6 +1632,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) for (pfn = start_pfn; pfn < end_pfn; pfn++) { struct folio *folio; + bool isolated; if (!pfn_valid(pfn)) continue; @@ -1667,9 +1668,10 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) * We can skip free pages. And we can deal with pages on * LRU and non-lru movable pages. */ - if (PageLRU(page)) - ret = isolate_lru_page(page); - else + if (PageLRU(page)) { + isolated = isolate_lru_page(page); + ret = isolated ? 0 : -EBUSY; + } else ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE); if (!ret) { /* Success */ list_add_tail(&page->lru, &source); diff --git a/mm/migrate.c b/mm/migrate.c index ef68a1aff35c..53010a142e7f 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2132,11 +2132,14 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, } } else { struct page *head; + bool isolated; head = compound_head(page); - err = isolate_lru_page(head); - if (err) + isolated = isolate_lru_page(head); + if (!isolated) { + err = -EBUSY; goto out_putpage; + } err = 1; list_add_tail(&head->lru, pagelist); @@ -2541,7 +2544,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) return 0; } - if (isolate_lru_page(page)) + if (!isolate_lru_page(page)) return 0; mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_is_file_lru(page), diff --git a/mm/migrate_device.c b/mm/migrate_device.c index 6c3740318a98..d30c9de60b0d 100644 --- a/mm/migrate_device.c +++ b/mm/migrate_device.c @@ -388,7 +388,7 @@ static unsigned long migrate_device_unmap(unsigned long *src_pfns, allow_drain = false; } - if (isolate_lru_page(page)) { + if (!isolate_lru_page(page)) { src_pfns[i] &= ~MIGRATE_PFN_MIGRATE; restore++; continue;