[PATCH v4 1/4] mm: move some shrinker-related function declarations to mm/internal.h

[Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>]

The following functions are only used inside the mm subsystem, so it's
better to move their declarations to the mm/internal.h file.

1. shrinker_debugfs_add()
2. shrinker_debugfs_detach()
3. shrinker_debugfs_remove()

Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
 include/linux/shrinker.h | 19 -------------------
 mm/internal.h            | 26 ++++++++++++++++++++++++++
 mm/shrinker_debug.c      |  2 ++
 3 files changed, 28 insertions(+), 19 deletions(-)

diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h
index 224293b2dd06..8dc15aa37410 100644
--- a/include/linux/shrinker.h
+++ b/include/linux/shrinker.h
@@ -106,28 +106,9 @@ extern void free_prealloced_shrinker(struct shrinker *shrinker);
 extern void synchronize_shrinkers(void);
 
 #ifdef CONFIG_SHRINKER_DEBUG
-extern int shrinker_debugfs_add(struct shrinker *shrinker);
-extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,
-					      int *debugfs_id);
-extern void shrinker_debugfs_remove(struct dentry *debugfs_entry,
-				    int debugfs_id);
 extern int __printf(2, 3) shrinker_debugfs_rename(struct shrinker *shrinker,
 						  const char *fmt, ...);
 #else /* CONFIG_SHRINKER_DEBUG */
-static inline int shrinker_debugfs_add(struct shrinker *shrinker)
-{
-	return 0;
-}
-static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,
-						     int *debugfs_id)
-{
-	*debugfs_id = -1;
-	return NULL;
-}
-static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry,
-					   int debugfs_id)
-{
-}
 static inline __printf(2, 3)
 int shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...)
 {
diff --git a/mm/internal.h b/mm/internal.h
index 30cf724ddbce..939d1227a527 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1154,4 +1154,30 @@ struct vma_prepare {
 	struct vm_area_struct *remove;
 	struct vm_area_struct *remove2;
 };
+
+/* shrinker related functions */
+
+#ifdef CONFIG_SHRINKER_DEBUG
+extern int shrinker_debugfs_add(struct shrinker *shrinker);
+extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,
+					      int *debugfs_id);
+extern void shrinker_debugfs_remove(struct dentry *debugfs_entry,
+				    int debugfs_id);
+#else /* CONFIG_SHRINKER_DEBUG */
+static inline int shrinker_debugfs_add(struct shrinker *shrinker)
+{
+	return 0;
+}
+static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,
+						     int *debugfs_id)
+{
+	*debugfs_id = -1;
+	return NULL;
+}
+static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry,
+					   int debugfs_id)
+{
+}
+#endif /* CONFIG_SHRINKER_DEBUG */
+
 #endif	/* __MM_INTERNAL_H */
diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c
index 3ab53fad8876..ee0cddb4530f 100644
--- a/mm/shrinker_debug.c
+++ b/mm/shrinker_debug.c
@@ -6,6 +6,8 @@
 #include <linux/shrinker.h>
 #include <linux/memcontrol.h>
 
+#include "internal.h"
+
 /* defined in vmscan.c */
 extern struct rw_semaphore shrinker_rwsem;
 extern struct list_head shrinker_list;
-- 
2.30.2