mm: add zone counter for cma pages

Add per free area nr_free_cma counter. The idea is
to also track the number of cma pages present in
free pages. This will be used in later patches to
fix issues with zone_watermark_ok.

Change-Id: I97da9d2f3642db56fc541c48ab56a7ce78e2333c
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
(cherry picked from commit a147305588507b1a241af87f1006c5d0b30beade)

4 files changed, 36 insertions, 11 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 9ceef771f..c44cd2925 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -102,6 +102,7 @@ static inline int get_pageblock_migratetype(struct page *page)
 struct free_area {
 	struct list_head	free_list[MIGRATE_TYPES];
 	unsigned long		nr_free;
+	unsigned long		nr_free_cma;
 };
 
 struct pglist_data;
diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 843187592..6b6ad8a5c 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -37,10 +37,10 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 			 bool skip_hwpoisoned_pages);
 void set_pageblock_migratetype(struct page *page, int migratetype);
 int move_freepages_block(struct zone *zone, struct page *page,
-				int migratetype);
+				int migratetype, int old_mt);
 int move_freepages(struct zone *zone,
 			  struct page *start_page, struct page *end_page,
-			  int migratetype);
+			  int migratetype, int old_mt);
 
 /*
  * Changes migrate type in [start_pfn, end_pfn) to be MIGRATE_ISOLATE.
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 21686a238..430956db0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -621,6 +621,8 @@ static inline void __free_one_page(struct page *page,
 		} else {
 			list_del(&buddy->lru);
 			zone->free_area[order].nr_free--;
+			if (is_migrate_cma(migratetype))
+				zone->free_area[order].nr_free_cma--;
 			rmv_page_order(buddy);
 		}
 		combined_idx = buddy_idx & page_idx;
@@ -752,6 +754,8 @@ static inline void __free_one_page(struct page *page,
 	list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
 out:
 	zone->free_area[order].nr_free++;
+	if (is_migrate_cma(migratetype))
+		zone->free_area[order].nr_free_cma++;
 }
 #endif
 
@@ -1081,6 +1085,8 @@ static inline void expand(struct zone *zone, struct page *page,
 #endif
 		list_add(&page[size].lru, &area->free_list[migratetype]);
 		area->nr_free++;
+		if (is_migrate_cma(migratetype))
+			area->nr_free_cma++;
 		set_page_order(&page[size], high);
 	}
 }
@@ -1152,6 +1158,8 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
 		list_del(&page->lru);
 		rmv_page_order(page);
 		area->nr_free--;
+		if (is_migrate_cma(migratetype))
+			area->nr_free_cma--;
 		expand(zone, page, order, current_order, area, migratetype);
 		return page;
 	}
@@ -1218,7 +1226,7 @@ static int fallbacks[MIGRATE_TYPES][4] = {
  */
 int move_freepages(struct zone *zone,
 			  struct page *start_page, struct page *end_page,
-			  int migratetype)
+			  int migratetype, int old_mt)
 {
 	struct page *page;
 	unsigned long order;
@@ -1252,6 +1260,12 @@ int move_freepages(struct zone *zone,
 		order = page_order(page);
 		list_move(&page->lru,
 			  &zone->free_area[order].free_list[migratetype]);
+
+		if (is_migrate_cma(migratetype))
+			zone->free_area[order].nr_free_cma++;
+		else if (is_migrate_cma(old_mt))
+			zone->free_area[order].nr_free_cma--;
+
 		set_freepage_migratetype(page, migratetype);
 		page += 1 << order;
 		pages_moved += 1 << order;
@@ -1261,7 +1275,7 @@ int move_freepages(struct zone *zone,
 }
 
 int move_freepages_block(struct zone *zone, struct page *page,
-				int migratetype)
+				int migratetype, int old_mt)
 {
 	unsigned long start_pfn, end_pfn;
 	struct page *start_page, *end_page;
@@ -1278,7 +1292,7 @@ int move_freepages_block(struct zone *zone, struct page *page,
 	if (!zone_spans_pfn(zone, end_pfn))
 		return 0;
 
-	return move_freepages(zone, start_page, end_page, migratetype);
+	return move_freepages(zone, start_page, end_page, migratetype, old_mt);
 }
 
 static void change_pageblock_range(struct page *pageblock_page,
@@ -1326,6 +1340,8 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
 			page = list_entry(area->free_list[migratetype].next,
 					struct page, lru);
 			area->nr_free--;
+			if (is_migrate_cma(migratetype))
+				area->nr_free_cma--;
 
 			/* We don't want move pages with MIGRATE_MTKPASR to other mobilities either! */
 			if (is_migrate_mtkpasr(migratetype)) {
@@ -1374,7 +1390,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
 			     page_group_by_mobility_disabled)) {
 				int pages;
 				pages = move_freepages_block(zone, page,
-								start_migratetype);
+								start_migratetype, 0);
 
 				/* Claim the whole block if over half of it is free */
 				if (pages >= (1 << (pageblock_order-1)) ||
@@ -1776,6 +1792,8 @@ int __isolate_free_page(struct page *page, unsigned int order)
 	/* Remove page from free list */
 	list_del(&page->lru);
 	zone->free_area[order].nr_free--;
+	if (is_migrate_cma(mt))
+		zone->free_area[order].nr_free_cma--;
 	rmv_page_order(page);
 
 	/* Set the pageblock if the isolated page is at least a pageblock */
@@ -4596,7 +4614,7 @@ static void setup_zone_migrate_reserve(struct zone *zone)
 				set_pageblock_migratetype(page,
 							MIGRATE_RESERVE);
 				move_freepages_block(zone, page,
-							MIGRATE_RESERVE);
+						MIGRATE_RESERVE, 0);
 				reserve--;
 				continue;
 			}
@@ -4608,7 +4626,8 @@ static void setup_zone_migrate_reserve(struct zone *zone)
 		 */
 		if (block_migratetype == MIGRATE_RESERVE) {
 			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
-			move_freepages_block(zone, page, MIGRATE_MOVABLE);
+			move_freepages_block(zone, page,
+					MIGRATE_MOVABLE, 0);
 		}
 	}
 }
@@ -4698,6 +4717,7 @@ static void __meminit zone_init_free_lists(struct zone *zone)
 	for_each_migratetype_order(order, t) {
 		INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
 		zone->free_area[order].nr_free = 0;
+		zone->free_area[order].nr_free_cma = 0;
 	}
 }
 
@@ -7525,6 +7545,8 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
 		if (PageHighMem(page))
 			totalhigh_pages -= 1 << order;
 #endif
+		if (is_migrate_cma(get_pageblock_migratetype(page)))
+			zone->free_area[order].nr_free_cma--;
 		for (i = 0; i < (1 << order); i++)
 			SetPageReserved((page+i));
 		pfn += (1 << order);
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 87011247a..0e55d52c5 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -65,7 +65,8 @@ out:
 // commit ad53f92eb416d81e469fa8ea57153e59455e7175
 		zone->nr_isolate_pageblock++;
 #endif
-		nr_pages = move_freepages_block(zone, page, MIGRATE_ISOLATE);
+		nr_pages = move_freepages_block(zone, page,
+				MIGRATE_ISOLATE, migratetype);
 
 #if !defined(CONFIG_CMA) || !defined(CONFIG_MTK_SVP) // SVP 16
 		__mod_zone_freepage_state(zone, -nr_pages, migratetype);
@@ -141,7 +142,8 @@ void unset_migratetype_isolate(struct page *page, unsigned migratetype)
 	 * pageblock scanning for freepage moving.
 	 */
 	if (!isolated_page) {
-		nr_pages = move_freepages_block(zone, page, migratetype);
+		nr_pages = move_freepages_block(zone, page,
+				migratetype, 0);
 #if !defined(CONFIG_CMA) || !defined(CONFIG_MTK_SVP) // SVP 16
 		__mod_zone_freepage_state(zone, nr_pages, migratetype);
 #else
@@ -274,7 +276,7 @@ __test_page_isolated_in_pageblock(struct zone *zone, unsigned long pfn,
 
 				end_page = page + (1 << page_order(page)) - 1;
 				move_freepages(page_zone(page), page, end_page,
-						MIGRATE_ISOLATE);
+						MIGRATE_ISOLATE,0);
 			}
 			pfn += 1 << page_order(page);
 		}