1 files changed, 104 insertions, 0 deletions
diff --git a/include/linux/compaction.h b/include/linux/compaction.h
new file mode 100644
index 000000000..aa8f61cf3
--- /dev/null
+++ b/include/linux/compaction.h
@@ -0,0 +1,104 @@
+#ifndef _LINUX_COMPACTION_H
+#define _LINUX_COMPACTION_H
+
+/* Return values for compact_zone() and try_to_compact_pages() */
+/* compaction didn't start as it was deferred due to past failures */
+#define COMPACT_DEFERRED	0
+/* compaction didn't start as it was not possible or direct reclaim was more suitable */
+#define COMPACT_SKIPPED		1
+/* compaction should continue to another pageblock */
+#define COMPACT_CONTINUE	2
+/* direct compaction partially compacted a zone and there are suitable pages */
+#define COMPACT_PARTIAL		3
+/* The full zone was compacted */
+#define COMPACT_COMPLETE	4
+/* For more detailed tracepoint output */
+#define COMPACT_NO_SUITABLE_PAGE	5
+#define COMPACT_NOT_SUITABLE_ZONE	6
+/* When adding new state, please change compaction_status_string, too */
+
+/* Used to signal whether compaction detected need_sched() or lock contention */
+/* No contention detected */
+#define COMPACT_CONTENDED_NONE	0
+/* Either need_sched() was true or fatal signal pending */
+#define COMPACT_CONTENDED_SCHED	1
+/* Zone lock or lru_lock was contended in async compaction */
+#define COMPACT_CONTENDED_LOCK	2
+
+struct alloc_context; /* in mm/internal.h */
+
+#ifdef CONFIG_COMPACTION
+extern int sysctl_compact_memory;
+extern int sysctl_compaction_handler(struct ctl_table *table, int write,
+			void __user *buffer, size_t *length, loff_t *ppos);
+extern int sysctl_extfrag_threshold;
+extern int sysctl_extfrag_handler(struct ctl_table *table, int write,
+			void __user *buffer, size_t *length, loff_t *ppos);
+extern int sysctl_compact_unevictable_allowed;
+
+extern int fragmentation_index(struct zone *zone, unsigned int order);
+extern unsigned long 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);
+extern void compact_pgdat(pg_data_t *pgdat, int order);
+extern void reset_isolation_suitable(pg_data_t *pgdat);
+extern unsigned long compaction_suitable(struct zone *zone, int order,
+					int alloc_flags, int classzone_idx);
+
+extern void defer_compaction(struct zone *zone, int order);
+extern bool compaction_deferred(struct zone *zone, int order);
+extern void compaction_defer_reset(struct zone *zone, int order,
+				bool alloc_success);
+extern bool compaction_restarting(struct zone *zone, int order);
+
+#else
+static inline unsigned long 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)
+{
+}
+
+static inline void reset_isolation_suitable(pg_data_t *pgdat)
+{
+}
+
+static inline unsigned long compaction_suitable(struct zone *zone, int order,
+					int alloc_flags, int classzone_idx)
+{
+	return COMPACT_SKIPPED;
+}
+
+static inline void defer_compaction(struct zone *zone, int order)
+{
+}
+
+static inline bool compaction_deferred(struct zone *zone, int order)
+{
+	return true;
+}
+
+#endif /* CONFIG_COMPACTION */
+
+#if defined(CONFIG_COMPACTION) && defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
+extern int compaction_register_node(struct node *node);
+extern void compaction_unregister_node(struct node *node);
+
+#else
+
+static inline int compaction_register_node(struct node *node)
+{
+	return 0;
+}
+
+static inline void compaction_unregister_node(struct node *node)
+{
+}
+#endif /* CONFIG_COMPACTION && CONFIG_SYSFS && CONFIG_NUMA */
+
+#endif /* _LINUX_COMPACTION_H */