mm/damon/core: split damos application logic into a new function

The DAMOS action applying function, 'damon_do_apply_schemes()', is still
long and not easy to read.  Split out the code for applying a single
action to a single region into a new function for better readability.

Link: https://lkml.kernel.org/r/20221026225943.100429-3-sj@kernel.orgSigned-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/damon/core.c

@@ -755,6 +755,44 @@ static bool damos_skip_charged_region(struct damon_target *t,
 	return false;
 }
 
+static void damos_apply_scheme(struct damon_ctx *c, struct damon_target *t,
+		struct damon_region *r, struct damos *s)
+{
+	struct damos_quota *quota = &s->quota;
+	unsigned long sz = damon_sz_region(r);
+	struct timespec64 begin, end;
+	unsigned long sz_applied = 0;
+
+	if (c->ops.apply_scheme) {
+		if (quota->esz && quota->charged_sz + sz > quota->esz) {
+			sz = ALIGN_DOWN(quota->esz - quota->charged_sz,
+					DAMON_MIN_REGION);
+			if (!sz)
+				goto update_stat;
+			damon_split_region_at(t, r, sz);
+		}
+		ktime_get_coarse_ts64(&begin);
+		sz_applied = c->ops.apply_scheme(c, t, r, s);
+		ktime_get_coarse_ts64(&end);
+		quota->total_charged_ns += timespec64_to_ns(&end) -
+			timespec64_to_ns(&begin);
+		quota->charged_sz += sz;
+		if (quota->esz && quota->charged_sz >= quota->esz) {
+			quota->charge_target_from = t;
+			quota->charge_addr_from = r->ar.end + 1;
+		}
+	}
+	if (s->action != DAMOS_STAT)
+		r->age = 0;
+
+update_stat:
+	s->stat.nr_tried++;
+	s->stat.sz_tried += sz;
+	if (sz_applied)
+		s->stat.nr_applied++;
+	s->stat.sz_applied += sz_applied;
+}
+
 static void damon_do_apply_schemes(struct damon_ctx *c,
 				   struct damon_target *t,
 				   struct damon_region *r)
@@ -763,9 +801,6 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 
 	damon_for_each_scheme(s, c) {
 		struct damos_quota *quota = &s->quota;
-		unsigned long sz;
-		struct timespec64 begin, end;
-		unsigned long sz_applied = 0;
 
 		if (!s->wmarks.activated)
 			continue;
@@ -780,37 +815,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 		if (!damos_valid_target(c, t, r, s))
 			continue;
 
-		/* Apply the scheme */
-		sz = damon_sz_region(r);
-		if (c->ops.apply_scheme) {
-			if (quota->esz &&
-					quota->charged_sz + sz > quota->esz) {
-				sz = ALIGN_DOWN(quota->esz - quota->charged_sz,
-						DAMON_MIN_REGION);
-				if (!sz)
-					goto update_stat;
-				damon_split_region_at(t, r, sz);
-			}
-			ktime_get_coarse_ts64(&begin);
-			sz_applied = c->ops.apply_scheme(c, t, r, s);
-			ktime_get_coarse_ts64(&end);
-			quota->total_charged_ns += timespec64_to_ns(&end) -
-				timespec64_to_ns(&begin);
-			quota->charged_sz += sz;
-			if (quota->esz && quota->charged_sz >= quota->esz) {
-				quota->charge_target_from = t;
-				quota->charge_addr_from = r->ar.end + 1;
-			}
-		}
-		if (s->action != DAMOS_STAT)
-			r->age = 0;
-
-update_stat:
-		s->stat.nr_tried++;
-		s->stat.sz_tried += sz;
-		if (sz_applied)
-			s->stat.nr_applied++;
-		s->stat.sz_applied += sz_applied;
+		damos_apply_scheme(c, t, r, s);
 	}
 }