From 77f1fe6b08b13a87391549c8a820ddc817b6f50e Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Thu, 13 Jan 2011 15:45:57 -0800 Subject: mm: migration: allow migration to operate asynchronously and avoid synchronous compaction in the faster path Migration synchronously waits for writeback if the initial passes fails. Callers of memory compaction do not necessarily want this behaviour if the caller is latency sensitive or expects that synchronous migration is not going to have a significantly better success rate. This patch adds a sync parameter to migrate_pages() allowing the caller to indicate if wait_on_page_writeback() is allowed within migration or not. For reclaim/compaction, try_to_compact_pages() is first called asynchronously, direct reclaim runs and then try_to_compact_pages() is called synchronously as there is a greater expectation that it'll succeed. [akpm@linux-foundation.org: build/merge fix] Signed-off-by: Mel Gorman Cc: Andrea Arcangeli Cc: KOSAKI Motohiro Cc: Rik van Riel Acked-by: Johannes Weiner Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/migrate.h | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 085527fb826..fa31902803f 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -13,9 +13,11 @@ extern void putback_lru_pages(struct list_head *l); extern int migrate_page(struct address_space *, struct page *, struct page *); extern int migrate_pages(struct list_head *l, new_page_t x, - unsigned long private, int offlining); + unsigned long private, int offlining, + bool sync); extern int migrate_huge_pages(struct list_head *l, new_page_t x, - unsigned long private, int offlining); + unsigned long private, int offlining, + bool sync); extern int fail_migrate_page(struct address_space *, struct page *, struct page *); @@ -33,9 +35,11 @@ extern int migrate_huge_page_move_mapping(struct address_space *mapping, static inline void putback_lru_pages(struct list_head *l) {} static inline int migrate_pages(struct list_head *l, new_page_t x, - unsigned long private, int offlining) { return -ENOSYS; } + unsigned long private, int offlining, + bool sync) { return -ENOSYS; } static inline int migrate_huge_pages(struct list_head *l, new_page_t x, - unsigned long private, int offlining) { return -ENOSYS; } + unsigned long private, int offlining, + bool sync) { return -ENOSYS; } static inline int migrate_prep(void) { return -ENOSYS; } static inline int migrate_prep_local(void) { return -ENOSYS; } -- cgit v1.2.3-70-g09d2