mm, compaction: introduce direct compaction priority

[mirror_ubuntu-zesty-kernel.git] / include / linux / compaction.h

diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index a58c852a268fd9ef4e78873a781c2c0371df4328..0980a6ce44360b7facb28b9cbce7c75f47ea2494 100644 (file)
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -1,6 +1,18 @@
 #ifndef _LINUX_COMPACTION_H
 #define _LINUX_COMPACTION_H
 
+/*
+ * Determines how hard direct compaction should try to succeed.
+ * Lower value means higher priority, analogically to reclaim priority.
+ */
+enum compact_priority {
+       COMPACT_PRIO_SYNC_LIGHT,
+       MIN_COMPACT_PRIORITY = COMPACT_PRIO_SYNC_LIGHT,
+       DEF_COMPACT_PRIORITY = COMPACT_PRIO_SYNC_LIGHT,
+       COMPACT_PRIO_ASYNC,
+       INIT_COMPACT_PRIORITY = COMPACT_PRIO_ASYNC
+};
+
 /* Return values for compact_zone() and try_to_compact_pages() */
 /* When adding new states, please adjust include/trace/events/compaction.h */
 enum compact_result {
@@ -66,7 +78,7 @@ extern int fragmentation_index(struct zone *zone, unsigned int order);
 extern enum compact_result try_to_compact_pages(gfp_t gfp_mask,
                        unsigned int order,
                unsigned int alloc_flags, const struct alloc_context *ac,
-               enum migrate_mode mode, int *contended);
+               enum compact_priority prio, int *contended);
 extern void compact_pgdat(pg_data_t *pgdat, int order);
 extern void reset_isolation_suitable(pg_data_t *pgdat);
 extern enum compact_result compaction_suitable(struct zone *zone, int order,
@@ -151,14 +163,6 @@ extern void kcompactd_stop(int nid);
 extern void wakeup_kcompactd(pg_data_t *pgdat, int order, int classzone_idx);
 
 #else
-static inline enum compact_result try_to_compact_pages(gfp_t gfp_mask,
-                       unsigned int order, int alloc_flags,
-                       const struct alloc_context *ac,
-                       enum migrate_mode mode, int *contended)
-{
-       return COMPACT_CONTINUE;
-}
-
 static inline void compact_pgdat(pg_data_t *pgdat, int order)
 {
 }
@@ -212,6 +216,7 @@ static inline void wakeup_kcompactd(pg_data_t *pgdat, int order, int classzone_i
 #endif /* CONFIG_COMPACTION */
 
 #if defined(CONFIG_COMPACTION) && defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
+struct node;
 extern int compaction_register_node(struct node *node);
 extern void compaction_unregister_node(struct node *node);