mm/damon: move sz_damon_region to damon_sz_region

Rename sz_damon_region() to damon_sz_region(), and move it to
"include/linux/damon.h", because in many places, we can to use this func.

Link: https://lkml.kernel.org/r/20220927001946.85375-1-xhao@linux.alibaba.comSigned-off-by: NXin Hao <xhao@linux.alibaba.com>
Suggested-by: NSeongJae Park <sj@kernel.org>
Reviewed-by: NSeongJae Park <sj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

include/linux/damon.h

@@ -484,6 +484,12 @@ static inline struct damon_region *damon_first_region(struct damon_target *t)
 	return list_first_entry(&t->regions_list, struct damon_region, list);
 }
 
+static inline unsigned long damon_sz_region(struct damon_region *r)
+{
+	return r->ar.end - r->ar.start;
+}
+
+
 #define damon_for_each_region(r, t) \
 	list_for_each_entry(r, &t->regions_list, list)
 

mm/damon/core.c

@@ -864,18 +864,13 @@ static void kdamond_apply_schemes(struct damon_ctx *c)
 	}
 }
 
-static inline unsigned long sz_damon_region(struct damon_region *r)
-{
-	return r->ar.end - r->ar.start;
-}
-
 /*
  * Merge two adjacent regions into one region
  */
 static void damon_merge_two_regions(struct damon_target *t,
 		struct damon_region *l, struct damon_region *r)
 {
-	unsigned long sz_l = sz_damon_region(l), sz_r = sz_damon_region(r);
+	unsigned long sz_l = damon_sz_region(l), sz_r = damon_sz_region(r);
 
 	l->nr_accesses = (l->nr_accesses * sz_l + r->nr_accesses * sz_r) /
 			(sz_l + sz_r);
@@ -904,7 +899,7 @@ static void damon_merge_regions_of(struct damon_target *t, unsigned int thres,
 
 		if (prev && prev->ar.end == r->ar.start &&
 		    abs(prev->nr_accesses - r->nr_accesses) <= thres &&
-		    sz_damon_region(prev) + sz_damon_region(r) <= sz_limit)
+		    damon_sz_region(prev) + damon_sz_region(r) <= sz_limit)
 			damon_merge_two_regions(t, prev, r);
 		else
 			prev = r;