[054/118] mm: remove "count" parameter from has_unmovable_pages()

Commit Message

Andrew Morton Jan. 31, 2020, 6:14 a.m. UTC

From: David Hildenbrand <[e-mail]>
Subject: mm: remove "count" parameter from has_unmovable_pages()

Now that the memory isolate notifier is gone, the parameter is always 0. 
Drop it and cleanup has_unmovable_pages().

Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: David Hildenbrand <[e-mail]>
Acked-by: Michal Hocko <[e-mail]>
Cc: Oscar Salvador <[e-mail]>
Cc: Anshuman Khandual <[e-mail]>
Cc: Qian Cai <[e-mail]>
Cc: Pingfan Liu <[e-mail]>
Cc: Stephen Rothwell <[e-mail]>
Cc: Dan Williams <[e-mail]>
Cc: Pavel Tatashin <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
Cc: Mel Gorman <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Wei Yang <[e-mail]>
Cc: Alexander Duyck <[e-mail]>
Cc: Alexander Potapenko <[e-mail]>
Cc: Arun KS <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 include/linux/page-isolation.h |    4 ++--
 mm/memory_hotplug.c            |    2 +-
 mm/page_alloc.c                |   21 +++++++--------------
 mm/page_isolation.c            |    2 +-
 4 files changed, 11 insertions(+), 18 deletions(-)

Patch

--- a/include/linux/page-isolation.h~mm-remove-count-parameter-from-has_unmovable_pages
+++ a/include/linux/page-isolation.h
@@ -33,8 +33,8 @@  static inline bool is_migrate_isolate(in
 #define MEMORY_OFFLINE	0x1
 #define REPORT_FAILURE	0x2
 
-bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
-			 int migratetype, int flags);
+bool has_unmovable_pages(struct zone *zone, struct page *page, int migratetype,
+			 int flags);
 void set_pageblock_migratetype(struct page *page, int migratetype);
 int move_freepages_block(struct zone *zone, struct page *page,
 				int migratetype, int *num_movable);
--- a/mm/memory_hotplug.c~mm-remove-count-parameter-from-has_unmovable_pages
+++ a/mm/memory_hotplug.c
@@ -1182,7 +1182,7 @@  static bool is_pageblock_removable_noloc
 	if (!zone_spans_pfn(zone, pfn))
 		return false;
 
-	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE,
+	return !has_unmovable_pages(zone, page, MIGRATE_MOVABLE,
 				    MEMORY_OFFLINE);
 }
 
--- a/mm/page_alloc.c~mm-remove-count-parameter-from-has_unmovable_pages
+++ a/mm/page_alloc.c
@@ -8180,17 +8180,15 @@  void *__init alloc_large_system_hash(con
 
 /*
  * This function checks whether pageblock includes unmovable pages or not.
- * If @count is not zero, it is okay to include less @count unmovable pages
  *
  * PageLRU check without isolation or lru_lock could race so that
  * MIGRATE_MOVABLE block might include unmovable pages. And __PageMovable
  * check without lock_page also may miss some movable non-lru pages at
  * race condition. So you can't expect this function should be exact.
  */
-bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
-			 int migratetype, int flags)
+bool has_unmovable_pages(struct zone *zone, struct page *page, int migratetype,
+			 int flags)
 {
-	unsigned long found;
 	unsigned long iter = 0;
 	unsigned long pfn = page_to_pfn(page);
 	const char *reason = "unmovable page";
@@ -8216,13 +8214,11 @@  bool has_unmovable_pages(struct zone *zo
 		goto unmovable;
 	}
 
-	for (found = 0; iter < pageblock_nr_pages; iter++) {
-		unsigned long check = pfn + iter;
-
-		if (!pfn_valid_within(check))
+	for (; iter < pageblock_nr_pages; iter++) {
+		if (!pfn_valid_within(pfn + iter))
 			continue;
 
-		page = pfn_to_page(check);
+		page = pfn_to_page(pfn + iter);
 
 		if (PageReserved(page))
 			goto unmovable;
@@ -8271,11 +8267,9 @@  bool has_unmovable_pages(struct zone *zo
 		if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
 			continue;
 
-		if (__PageMovable(page))
+		if (__PageMovable(page) || PageLRU(page))
 			continue;
 
-		if (!PageLRU(page))
-			found++;
 		/*
 		 * If there are RECLAIMABLE pages, we need to check
 		 * it.  But now, memory offline itself doesn't call
@@ -8289,8 +8283,7 @@  bool has_unmovable_pages(struct zone *zo
 		 * is set to both of a memory hole page and a _used_ kernel
 		 * page at boot.
 		 */
-		if (found > count)
-			goto unmovable;
+		goto unmovable;
 	}
 	return false;
 unmovable:
--- a/mm/page_isolation.c~mm-remove-count-parameter-from-has_unmovable_pages
+++ a/mm/page_isolation.c
@@ -37,7 +37,7 @@  static int set_migratetype_isolate(struc
 	 * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.
 	 * We just check MOVABLE pages.
 	 */
-	if (!has_unmovable_pages(zone, page, 0, migratetype, isol_flags)) {
+	if (!has_unmovable_pages(zone, page, migratetype, isol_flags)) {
 		unsigned long nr_pages;
 		int mt = get_pageblock_migratetype(page);