[PATCH 1/3] mm: move struct scan_control into internal.h

[Yafang Shao <laoar.shao@gmail.com>]

This struct will be used in multiple source file under mm/, so move the
definition of it into mm/internal.h.

Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Chris Down <chris@chrisdown.name>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
 mm/internal.h | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++
 mm/vmscan.c   | 83 --------------------------------------------------
 2 files changed, 84 insertions(+), 83 deletions(-)

diff --git a/mm/internal.h b/mm/internal.h
index b5634e78f01d..a0b3bdd933b9 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -11,6 +11,7 @@
 #include <linux/mm.h>
 #include <linux/pagemap.h>
 #include <linux/tracepoint-defs.h>
+#include <linux/swap.h>
 
 /*
  * The set of flags that only affect watermark checking and reclaim
@@ -254,6 +255,89 @@ int find_suitable_fallback(struct free_area *area, unsigned int order,
 
 #endif
 
+struct scan_control {
+	/* How many pages shrink_list() should reclaim */
+	unsigned long nr_to_reclaim;
+
+	/*
+	 * Nodemask of nodes allowed by the caller. If NULL, all nodes
+	 * are scanned.
+	 */
+	nodemask_t	*nodemask;
+
+	/*
+	 * The memory cgroup that hit its limit and as a result is the
+	 * primary target of this reclaim invocation.
+	 */
+	struct mem_cgroup *target_mem_cgroup;
+
+	/* Can active pages be deactivated as part of reclaim? */
+#define DEACTIVATE_ANON 1
+#define DEACTIVATE_FILE 2
+	unsigned int may_deactivate:2;
+	unsigned int force_deactivate:1;
+	unsigned int skipped_deactivate:1;
+
+	/* Writepage batching in laptop mode; RECLAIM_WRITE */
+	unsigned int may_writepage:1;
+
+	/* Can mapped pages be reclaimed? */
+	unsigned int may_unmap:1;
+
+	/* Can pages be swapped as part of reclaim? */
+	unsigned int may_swap:1;
+
+	/*
+	 * Cgroups are not reclaimed below their configured memory.low,
+	 * unless we threaten to OOM. If any cgroups are skipped due to
+	 * memory.low and nothing was reclaimed, go back for memory.low.
+	 */
+	unsigned int memcg_low_reclaim:1;
+	unsigned int memcg_low_skipped:1;
+
+	unsigned int hibernation_mode:1;
+
+	/* One of the zones is ready for compaction */
+	unsigned int compaction_ready:1;
+
+	/* There is easily reclaimable cold cache in the current node */
+	unsigned int cache_trim_mode:1;
+
+	/* The file pages on the current node are dangerously low */
+	unsigned int file_is_tiny:1;
+
+	/* Allocation order */
+	s8 order;
+
+	/* Scan (total_size >> priority) pages at once */
+	s8 priority;
+
+	/* The highest zone to isolate pages for reclaim from */
+	s8 reclaim_idx;
+
+	/* This context's GFP mask */
+	gfp_t gfp_mask;
+
+	/* Incremented by the number of inactive pages that were scanned */
+	unsigned long nr_scanned;
+
+	/* Number of pages freed so far during a call to shrink_zones() */
+	unsigned long nr_reclaimed;
+
+	struct {
+		unsigned int dirty;
+		unsigned int unqueued_dirty;
+		unsigned int congested;
+		unsigned int writeback;
+		unsigned int immediate;
+		unsigned int file_taken;
+		unsigned int taken;
+	} nr;
+
+	/* for recording the reclaimed slab by now */
+	struct reclaim_state reclaim_state;
+};
+
 /*
  * This function returns the order of a free page in the buddy system. In
  * general, page_zone(page)->lock must be held by the caller to prevent the
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b06868fc4926..4c98512e2c9f 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -63,89 +63,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/vmscan.h>
 
-struct scan_control {
-	/* How many pages shrink_list() should reclaim */
-	unsigned long nr_to_reclaim;
-
-	/*
-	 * Nodemask of nodes allowed by the caller. If NULL, all nodes
-	 * are scanned.
-	 */
-	nodemask_t	*nodemask;
-
-	/*
-	 * The memory cgroup that hit its limit and as a result is the
-	 * primary target of this reclaim invocation.
-	 */
-	struct mem_cgroup *target_mem_cgroup;
-
-	/* Can active pages be deactivated as part of reclaim? */
-#define DEACTIVATE_ANON 1
-#define DEACTIVATE_FILE 2
-	unsigned int may_deactivate:2;
-	unsigned int force_deactivate:1;
-	unsigned int skipped_deactivate:1;
-
-	/* Writepage batching in laptop mode; RECLAIM_WRITE */
-	unsigned int may_writepage:1;
-
-	/* Can mapped pages be reclaimed? */
-	unsigned int may_unmap:1;
-
-	/* Can pages be swapped as part of reclaim? */
-	unsigned int may_swap:1;
-
-	/*
-	 * Cgroups are not reclaimed below their configured memory.low,
-	 * unless we threaten to OOM. If any cgroups are skipped due to
-	 * memory.low and nothing was reclaimed, go back for memory.low.
-	 */
-	unsigned int memcg_low_reclaim:1;
-	unsigned int memcg_low_skipped:1;
-
-	unsigned int hibernation_mode:1;
-
-	/* One of the zones is ready for compaction */
-	unsigned int compaction_ready:1;
-
-	/* There is easily reclaimable cold cache in the current node */
-	unsigned int cache_trim_mode:1;
-
-	/* The file pages on the current node are dangerously low */
-	unsigned int file_is_tiny:1;
-
-	/* Allocation order */
-	s8 order;
-
-	/* Scan (total_size >> priority) pages at once */
-	s8 priority;
-
-	/* The highest zone to isolate pages for reclaim from */
-	s8 reclaim_idx;
-
-	/* This context's GFP mask */
-	gfp_t gfp_mask;
-
-	/* Incremented by the number of inactive pages that were scanned */
-	unsigned long nr_scanned;
-
-	/* Number of pages freed so far during a call to shrink_zones() */
-	unsigned long nr_reclaimed;
-
-	struct {
-		unsigned int dirty;
-		unsigned int unqueued_dirty;
-		unsigned int congested;
-		unsigned int writeback;
-		unsigned int immediate;
-		unsigned int file_taken;
-		unsigned int taken;
-	} nr;
-
-	/* for recording the reclaimed slab by now */
-	struct reclaim_state reclaim_state;
-};
-
 #ifdef ARCH_HAS_PREFETCHW
 #define prefetchw_prev_lru_page(_page, _base, _field)			\
 	do {								\
-- 
2.18.2