mm/damon: support multiple goal-based quota tuning algorithms

index 6bd71546f7b20..0824b953492e8 100644
@@ -215,12 +215,21 @@ struct damos_quota_goal {
 	struct list_head list;
 };
 
+/**
+ * enum damos_quota_goal_tuner - Goal-based quota tuning logic.
+ * @DAMOS_QUOTA_GOAL_TUNER_CONSIST:	Aim long term consistent quota.
+ */
+enum damos_quota_goal_tuner {
+	DAMOS_QUOTA_GOAL_TUNER_CONSIST,
+};
+
 /**
  * struct damos_quota - Controls the aggressiveness of the given scheme.
  * @reset_interval:	Charge reset interval in milliseconds.
  * @ms:			Maximum milliseconds that the scheme can use.
  * @sz:			Maximum bytes of memory that the action can be applied.
  * @goals:		Head of quota tuning goals (&damos_quota_goal) list.
+ * @goal_tuner:		Goal-based @esz tuning algorithm to use.
  * @esz:		Effective size quota in bytes.
  *
  * @weight_sz:		Weight of the region's size for prioritization.

@@ -262,6 +271,7 @@ struct damos_quota {
 	unsigned long ms;
 	unsigned long sz;
 	struct list_head goals;
+	enum damos_quota_goal_tuner goal_tuner;
 	unsigned long esz;
 
 	unsigned int weight_sz;

index 7f74982535aca..c16a390152790 100644
@@ -912,6 +912,7 @@ static int damos_commit_quota(struct damos_quota *dst, struct damos_quota *src)
 	err = damos_commit_quota_goals(dst, src);
 	if (err)
 		return err;
+	dst->goal_tuner = src->goal_tuner;
 	dst->weight_sz = src->weight_sz;
 	dst->weight_nr_accesses = src->weight_nr_accesses;
 	dst->weight_age = src->weight_age;

index c16a390152790..d351ef3bcf4e9 100644
@@ -387,6 +387,11 @@ void damos_destroy_quota_goal(struct damos_quota_goal *g)
 	damos_free_quota_goal(g);
 }
 
+static bool damos_quota_goals_empty(struct damos_quota *q)
+{
+	return list_empty(&q->goals);
+}
+
 /* initialize fields of @quota that normally API users wouldn't set */
 static struct damos_quota *damos_quota_init(struct damos_quota *quota)
 {

@@ -1789,12 +1794,24 @@ static bool __damos_valid_target(struct damon_region *r, struct damos *s)
 		r->age <= s->pattern.max_age_region;
 }
 
+/*
+ * damos_quota_is_set() - Return if the given quota is actually set.
+ * @quota:	The quota to check.
+ *
+ * Returns true if the quota is set, false otherwise.
+ */
+static bool damos_quota_is_set(struct damos_quota *quota)
+{
+	return quota->esz || quota->sz || quota->ms ||
+		!damos_quota_goals_empty(quota);
+}
+
 static bool damos_valid_target(struct damon_ctx *c, struct damon_region *r,
 		struct damos *s)
 {
 	bool ret = __damos_valid_target(r, s);
 
-	if (!ret || !s->quota.esz || !c->ops.get_scheme_score)
+	if (!ret || !damos_quota_is_set(&s->quota) || !c->ops.get_scheme_score)
 		return ret;
 
 	return c->ops.get_scheme_score(c, r, s) >= s->quota.min_score;

@@ -2064,7 +2081,8 @@ static void damos_apply_scheme(struct damon_ctx *c, struct damon_target *t,
 	}
 
 	if (c->ops.apply_scheme) {
-		if (quota->esz && quota->charged_sz + sz > quota->esz) {
+		if (damos_quota_is_set(quota) &&
+				quota->charged_sz + sz > quota->esz) {
 			sz = ALIGN_DOWN(quota->esz - quota->charged_sz,
 					c->min_region_sz);
 			if (!sz)

@@ -2083,7 +2101,8 @@ static void damos_apply_scheme(struct damon_ctx *c, struct damon_target *t,
 		quota->total_charged_ns += timespec64_to_ns(&end) -
 			timespec64_to_ns(&begin);
 		quota->charged_sz += sz;
-		if (quota->esz && quota->charged_sz >= quota->esz) {
+		if (damos_quota_is_set(quota) &&
+				quota->charged_sz >= quota->esz) {
 			quota->charge_target_from = t;
 			quota->charge_addr_from = r->ar.end + 1;
 		}

@@ -2111,7 +2130,8 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 			continue;
 
 		/* Check the quota */
-		if (quota->esz && quota->charged_sz >= quota->esz)
+		if (damos_quota_is_set(quota) &&
+				quota->charged_sz >= quota->esz)
 			continue;
 
 		if (damos_skip_charged_region(t, r, s, c->min_region_sz))

@@ -2396,7 +2416,8 @@ static void damos_adjust_quota(struct damon_ctx *c, struct damos *s)
 	/* 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)
+		if (damos_quota_is_set(quota) &&
+				quota->charged_sz >= quota->esz)
 			s->stat.qt_exceeds++;
 		quota->total_charged_sz += quota->charged_sz;
 		quota->charged_from = jiffies;

index 0824b953492e8..1130c2f9a92f4 100644
@@ -218,9 +218,11 @@ struct damos_quota_goal {
 /**
  * enum damos_quota_goal_tuner - Goal-based quota tuning logic.
  * @DAMOS_QUOTA_GOAL_TUNER_CONSIST:	Aim long term consistent quota.
+ * @DAMOS_QUOTA_GOAL_TUNER_TEMPORAL:	Aim zero quota asap.
  */
 enum damos_quota_goal_tuner {
 	DAMOS_QUOTA_GOAL_TUNER_CONSIST,
+	DAMOS_QUOTA_GOAL_TUNER_TEMPORAL,
 };
 
 /**

index d351ef3bcf4e9..2e36024d99506 100644
@@ -2345,6 +2345,26 @@ static unsigned long damos_quota_score(struct damos_quota *quota)
 	return highest_score;
 }
 
+static void damos_goal_tune_esz_bp_consist(struct damos_quota *quota)
+{
+	unsigned long score = damos_quota_score(quota);
+
+	quota->esz_bp = damon_feed_loop_next_input(
+			max(quota->esz_bp, 10000UL), score);
+}
+
+static void damos_goal_tune_esz_bp_temporal(struct damos_quota *quota)
+{
+	unsigned long score = damos_quota_score(quota);
+
+	if (score >= 10000)
+		quota->esz_bp = 0;
+	else if (quota->sz)
+		quota->esz_bp = quota->sz * 10000;
+	else
+		quota->esz_bp = ULONG_MAX;
+}
+
 /*
  * Called only if quota->ms, or quota->sz are set, or quota->goals is not empty
  */

@@ -2359,11 +2379,10 @@ static void damos_set_effective_quota(struct damos_quota *quota)
 	}
 
 	if (!list_empty(&quota->goals)) {
-		unsigned long score = damos_quota_score(quota);
-
-		quota->esz_bp = damon_feed_loop_next_input(
-				max(quota->esz_bp, 10000UL),
-				score);
+		if (quota->goal_tuner == DAMOS_QUOTA_GOAL_TUNER_CONSIST)
+			damos_goal_tune_esz_bp_consist(quota);
+		else if (quota->goal_tuner == DAMOS_QUOTA_GOAL_TUNER_TEMPORAL)
+			damos_goal_tune_esz_bp_temporal(quota);
 		esz = quota->esz_bp / 10000;
 	}
 

index 3a0782e576fab..5186966dafb35 100644
@@ -1488,6 +1488,7 @@ struct damon_sysfs_quotas {
 	unsigned long sz;
 	unsigned long reset_interval_ms;
 	unsigned long effective_sz;	/* Effective size quota in bytes */
+	enum damos_quota_goal_tuner goal_tuner;
 };
 
 static struct damon_sysfs_quotas *damon_sysfs_quotas_alloc(void)

@@ -1610,6 +1611,58 @@ static ssize_t effective_bytes_show(struct kobject *kobj,
 	return sysfs_emit(buf, "%lu\n", quotas->effective_sz);
 }
 
+struct damos_sysfs_qgoal_tuner_name {
+	enum damos_quota_goal_tuner tuner;
+	char *name;
+};
+
+static struct damos_sysfs_qgoal_tuner_name damos_sysfs_qgoal_tuner_names[] = {
+	{
+		.tuner = DAMOS_QUOTA_GOAL_TUNER_CONSIST,
+		.name = "consist",
+	},
+	{
+		.tuner = DAMOS_QUOTA_GOAL_TUNER_TEMPORAL,
+		.name = "temporal",
+	},
+};
+
+static ssize_t goal_tuner_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_quotas *quotas = container_of(kobj,
+			struct damon_sysfs_quotas, kobj);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(damos_sysfs_qgoal_tuner_names); i++) {
+		struct damos_sysfs_qgoal_tuner_name *tuner_name;
+
+		tuner_name = &damos_sysfs_qgoal_tuner_names[i];
+		if (tuner_name->tuner == quotas->goal_tuner)
+			return sysfs_emit(buf, "%s\n", tuner_name->name);
+	}
+	return -EINVAL;
+}
+
+static ssize_t goal_tuner_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_quotas *quotas = container_of(kobj,
+			struct damon_sysfs_quotas, kobj);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(damos_sysfs_qgoal_tuner_names); i++) {
+		struct damos_sysfs_qgoal_tuner_name *tuner_name;
+
+		tuner_name = &damos_sysfs_qgoal_tuner_names[i];
+		if (sysfs_streq(buf, tuner_name->name)) {
+			quotas->goal_tuner = tuner_name->tuner;
+			return count;
+		}
+	}
+	return -EINVAL;
+}
+
 static void damon_sysfs_quotas_release(struct kobject *kobj)
 {
 	kfree(container_of(kobj, struct damon_sysfs_quotas, kobj));

@@ -1627,11 +1680,15 @@ static struct kobj_attribute damon_sysfs_quotas_reset_interval_ms_attr =
 static struct kobj_attribute damon_sysfs_quotas_effective_bytes_attr =
 		__ATTR_RO_MODE(effective_bytes, 0400);
 
+static struct kobj_attribute damon_sysfs_quotas_goal_tuner_attr =
+		__ATTR_RW_MODE(goal_tuner, 0600);
+
 static struct attribute *damon_sysfs_quotas_attrs[] = {
 	&damon_sysfs_quotas_ms_attr.attr,
 	&damon_sysfs_quotas_sz_attr.attr,
 	&damon_sysfs_quotas_reset_interval_ms_attr.attr,
 	&damon_sysfs_quotas_effective_bytes_attr.attr,
+	&damon_sysfs_quotas_goal_tuner_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(damon_sysfs_quotas);

@@ -2718,6 +2775,7 @@ static struct damos *damon_sysfs_mk_scheme(
 		.weight_sz = sysfs_weights->sz,
 		.weight_nr_accesses = sysfs_weights->nr_accesses,
 		.weight_age = sysfs_weights->age,
+		.goal_tuner = sysfs_quotas->goal_tuner,
 	};
 	struct damos_watermarks wmarks = {
 		.metric = sysfs_wmarks->metric,

index e86d4f4fe261a..9e5904c2beeb2 100644
@@ -693,6 +693,7 @@ static void damos_test_commit_quota(struct kunit *test)
 		.reset_interval = 1,
 		.ms = 2,
 		.sz = 3,
+		.goal_tuner = DAMOS_QUOTA_GOAL_TUNER_CONSIST,
 		.weight_sz = 4,
 		.weight_nr_accesses = 5,
 		.weight_age = 6,

@@ -701,6 +702,7 @@ static void damos_test_commit_quota(struct kunit *test)
 		.reset_interval = 7,
 		.ms = 8,
 		.sz = 9,
+		.goal_tuner = DAMOS_QUOTA_GOAL_TUNER_TEMPORAL,
 		.weight_sz = 10,
 		.weight_nr_accesses = 11,
 		.weight_age = 12,

@@ -714,6 +716,7 @@ static void damos_test_commit_quota(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, dst.reset_interval, src.reset_interval);
 	KUNIT_EXPECT_EQ(test, dst.ms, src.ms);
 	KUNIT_EXPECT_EQ(test, dst.sz, src.sz);
+	KUNIT_EXPECT_EQ(test, dst.goal_tuner, src.goal_tuner);
 	KUNIT_EXPECT_EQ(test, dst.weight_sz, src.weight_sz);
 	KUNIT_EXPECT_EQ(test, dst.weight_nr_accesses, src.weight_nr_accesses);
 	KUNIT_EXPECT_EQ(test, dst.weight_age, src.weight_age);