mm/damon/core: split out scheme quota adjustment logic into a new function

DAMOS quota adjustment logic in 'kdamond_apply_schemes()', has some amount
of code, and the logic is not so straightforward.  Split it out to a new
function for better readability.

Link: https://lkml.kernel.org/r/20221026225943.100429-5-sj@kernel.orgSigned-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/damon/core.c

@@ -848,59 +848,64 @@ static void damos_set_effective_quota(struct damos_quota *quota)
 	quota->esz = esz;
 }
 
-static void kdamond_apply_schemes(struct damon_ctx *c)
+static void damos_adjust_quota(struct damon_ctx *c, struct damos *s)
 {
+	struct damos_quota *quota = &s->quota;
 	struct damon_target *t;
-	struct damon_region *r, *next_r;
-	struct damos *s;
+	struct damon_region *r;
+	unsigned long cumulated_sz;
+	unsigned int score, max_score = 0;
 
-	damon_for_each_scheme(s, c) {
-		struct damos_quota *quota = &s->quota;
-		unsigned long cumulated_sz;
-		unsigned int score, max_score = 0;
+	if (!quota->ms && !quota->sz)
+		return;
 
-		if (!s->wmarks.activated)
-			continue;
+	/* New charge window starts */
+	if (time_after_eq(jiffies, quota->charged_from +
+				msecs_to_jiffies(quota->reset_interval))) {
+		if (quota->esz && quota->charged_sz >= quota->esz)
+			s->stat.qt_exceeds++;
+		quota->total_charged_sz += quota->charged_sz;
+		quota->charged_from = jiffies;
+		quota->charged_sz = 0;
+		damos_set_effective_quota(quota);
+	}
 
-		if (!quota->ms && !quota->sz)
-			continue;
+	if (!c->ops.get_scheme_score)
+		return;
 
-		/* New charge window starts */
-		if (time_after_eq(jiffies, quota->charged_from +
-					msecs_to_jiffies(
-						quota->reset_interval))) {
-			if (quota->esz && quota->charged_sz >= quota->esz)
-				s->stat.qt_exceeds++;
-			quota->total_charged_sz += quota->charged_sz;
-			quota->charged_from = jiffies;
-			quota->charged_sz = 0;
-			damos_set_effective_quota(quota);
+	/* Fill up the score histogram */
+	memset(quota->histogram, 0, sizeof(quota->histogram));
+	damon_for_each_target(t, c) {
+		damon_for_each_region(r, t) {
+			if (!__damos_valid_target(r, s))
+				continue;
+			score = c->ops.get_scheme_score(c, t, r, s);
+			quota->histogram[score] += damon_sz_region(r);
+			if (score > max_score)
+				max_score = score;
 		}
+	}
 
-		if (!c->ops.get_scheme_score)
-			continue;
+	/* Set the min score limit */
+	for (cumulated_sz = 0, score = max_score; ; score--) {
+		cumulated_sz += quota->histogram[score];
+		if (cumulated_sz >= quota->esz || !score)
+			break;
+	}
+	quota->min_score = score;
+}
 
-		/* Fill up the score histogram */
-		memset(quota->histogram, 0, sizeof(quota->histogram));
-		damon_for_each_target(t, c) {
-			damon_for_each_region(r, t) {
-				if (!__damos_valid_target(r, s))
-					continue;
-				score = c->ops.get_scheme_score(
-						c, t, r, s);
-				quota->histogram[score] += damon_sz_region(r);
-				if (score > max_score)
-					max_score = score;
-			}
-		}
+static void kdamond_apply_schemes(struct damon_ctx *c)
+{
+	struct damon_target *t;
+	struct damon_region *r, *next_r;
+	struct damos *s;
 
-		/* Set the min score limit */
-		for (cumulated_sz = 0, score = max_score; ; score--) {
-			cumulated_sz += quota->histogram[score];
-			if (cumulated_sz >= quota->esz || !score)
-				break;
-		}
-		quota->min_score = score;
+	damon_for_each_scheme(s, c) {
+		if (!s->wmarks.activated)
+			continue;
+
+		damos_adjust_quota(c, s);
 	}
 
 	damon_for_each_target(t, c) {