--- a/include/linux/damon.h~mm-damon-core-implement-region-based-sampling
+++ a/include/linux/damon.h
@@ -12,6 +12,48 @@
 #include <linux/time64.h>
 #include <linux/types.h>
 
+/**
+ * struct damon_addr_range - Represents an address region of [@start, @end).
+ * @start:	Start address of the region (inclusive).
+ * @end:	End address of the region (exclusive).
+ */
+struct damon_addr_range {
+	unsigned long start;
+	unsigned long end;
+};
+
+/**
+ * struct damon_region - Represents a monitoring target region.
+ * @ar:			The address range of the region.
+ * @sampling_addr:	Address of the sample for the next access check.
+ * @nr_accesses:	Access frequency of this region.
+ * @list:		List head for siblings.
+ */
+struct damon_region {
+	struct damon_addr_range ar;
+	unsigned long sampling_addr;
+	unsigned int nr_accesses;
+	struct list_head list;
+};
+
+/**
+ * struct damon_target - Represents a monitoring target.
+ * @id:			Unique identifier for this target.
+ * @regions_list:	Head of the monitoring target regions of this target.
+ * @list:		List head for siblings.
+ *
+ * Each monitoring context could have multiple targets.  For example, a context
+ * for virtual memory address spaces could have multiple target processes.  The
+ * @id of each target should be unique among the targets of the context.  For
+ * example, in the virtual address monitoring context, it could be a pidfd or
+ * an address of an mm_struct.
+ */
+struct damon_target {
+	unsigned long id;
+	struct list_head regions_list;
+	struct list_head list;
+};
+
 struct damon_ctx;
 
 /**
@@ -36,7 +78,7 @@ struct damon_ctx;
  *
  * @init should initialize primitive-internal data structures.  For example,
  * this could be used to construct proper monitoring target regions and link
- * those to @damon_ctx.target.
+ * those to @damon_ctx.adaptive_targets.
  * @update should update the primitive-internal data structures.  For example,
  * this could be used to update monitoring target regions for current status.
  * @prepare_access_checks should manipulate the monitoring regions to be
@@ -130,7 +172,7 @@ struct damon_callback {
  * @primitive:	Set of monitoring primitives for given use cases.
  * @callback:	Set of callbacks for monitoring events notifications.
  *
- * @target:	Pointer to the user-defined monitoring target.
+ * @region_targets:	Head of monitoring targets (&damon_target) list.
  */
 struct damon_ctx {
 	unsigned long sample_interval;
@@ -149,11 +191,40 @@ struct damon_ctx {
 	struct damon_primitive primitive;
 	struct damon_callback callback;
 
-	void *target;
+	struct list_head region_targets;
 };
 
+#define damon_next_region(r) \
+	(container_of(r->list.next, struct damon_region, list))
+
+#define damon_prev_region(r) \
+	(container_of(r->list.prev, struct damon_region, list))
+
+#define damon_for_each_region(r, t) \
+	list_for_each_entry(r, &t->regions_list, list)
+
+#define damon_for_each_region_safe(r, next, t) \
+	list_for_each_entry_safe(r, next, &t->regions_list, list)
+
+#define damon_for_each_target(t, ctx) \
+	list_for_each_entry(t, &(ctx)->region_targets, list)
+
+#define damon_for_each_target_safe(t, next, ctx)	\
+	list_for_each_entry_safe(t, next, &(ctx)->region_targets, list)
+
 #ifdef CONFIG_DAMON
 
+struct damon_region *damon_new_region(unsigned long start, unsigned long end);
+inline void damon_insert_region(struct damon_region *r,
+		struct damon_region *prev, struct damon_region *next);
+void damon_add_region(struct damon_region *r, struct damon_target *t);
+void damon_destroy_region(struct damon_region *r);
+
+struct damon_target *damon_new_target(unsigned long id);
+void damon_add_target(struct damon_ctx *ctx, struct damon_target *t);
+void damon_free_target(struct damon_target *t);
+void damon_destroy_target(struct damon_target *t);
+
 struct damon_ctx *damon_new_ctx(void);
 void damon_destroy_ctx(struct damon_ctx *ctx);
 int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int,
--- a/mm/damon/core.c~mm-damon-core-implement-region-based-sampling
+++ a/mm/damon/core.c
@@ -15,6 +15,101 @@
 static DEFINE_MUTEX(damon_lock);
 static int nr_running_ctxs;
 
+/*
+ * Construct a damon_region struct
+ *
+ * Returns the pointer to the new struct if success, or NULL otherwise
+ */
+struct damon_region *damon_new_region(unsigned long start, unsigned long end)
+{
+	struct damon_region *region;
+
+	region = kmalloc(sizeof(*region), GFP_KERNEL);
+	if (!region)
+		return NULL;
+
+	region->ar.start = start;
+	region->ar.end = end;
+	region->nr_accesses = 0;
+	INIT_LIST_HEAD(&region->list);
+
+	return region;
+}
+
+/*
+ * Add a region between two other regions
+ */
+inline void damon_insert_region(struct damon_region *r,
+		struct damon_region *prev, struct damon_region *next)
+{
+	__list_add(&r->list, &prev->list, &next->list);
+}
+
+void damon_add_region(struct damon_region *r, struct damon_target *t)
+{
+	list_add_tail(&r->list, &t->regions_list);
+}
+
+static void damon_del_region(struct damon_region *r)
+{
+	list_del(&r->list);
+}
+
+static void damon_free_region(struct damon_region *r)
+{
+	kfree(r);
+}
+
+void damon_destroy_region(struct damon_region *r)
+{
+	damon_del_region(r);
+	damon_free_region(r);
+}
+
+/*
+ * Construct a damon_target struct
+ *
+ * Returns the pointer to the new struct if success, or NULL otherwise
+ */
+struct damon_target *damon_new_target(unsigned long id)
+{
+	struct damon_target *t;
+
+	t = kmalloc(sizeof(*t), GFP_KERNEL);
+	if (!t)
+		return NULL;
+
+	t->id = id;
+	INIT_LIST_HEAD(&t->regions_list);
+
+	return t;
+}
+
+void damon_add_target(struct damon_ctx *ctx, struct damon_target *t)
+{
+	list_add_tail(&t->list, &ctx->region_targets);
+}
+
+static void damon_del_target(struct damon_target *t)
+{
+	list_del(&t->list);
+}
+
+void damon_free_target(struct damon_target *t)
+{
+	struct damon_region *r, *next;
+
+	damon_for_each_region_safe(r, next, t)
+		damon_free_region(r);
+	kfree(t);
+}
+
+void damon_destroy_target(struct damon_target *t)
+{
+	damon_del_target(t);
+	damon_free_target(t);
+}
+
 struct damon_ctx *damon_new_ctx(void)
 {
 	struct damon_ctx *ctx;
@@ -32,15 +127,27 @@ struct damon_ctx *damon_new_ctx(void)
 
 	mutex_init(&ctx->kdamond_lock);
 
-	ctx->target = NULL;
+	INIT_LIST_HEAD(&ctx->region_targets);
 
 	return ctx;
 }
 
-void damon_destroy_ctx(struct damon_ctx *ctx)
+static void damon_destroy_targets(struct damon_ctx *ctx)
 {
-	if (ctx->primitive.cleanup)
+	struct damon_target *t, *next_t;
+
+	if (ctx->primitive.cleanup) {
 		ctx->primitive.cleanup(ctx);
+		return;
+	}
+
+	damon_for_each_target_safe(t, next_t, ctx)
+		damon_destroy_target(t);
+}
+
+void damon_destroy_ctx(struct damon_ctx *ctx)
+{
+	damon_destroy_targets(ctx);
 	kfree(ctx);
 }
 
@@ -218,6 +325,21 @@ static bool kdamond_aggregate_interval_p
 }
 
 /*
+ * Reset the aggregated monitoring results ('nr_accesses' of each region).
+ */
+static void kdamond_reset_aggregated(struct damon_ctx *c)
+{
+	struct damon_target *t;
+
+	damon_for_each_target(t, c) {
+		struct damon_region *r;
+
+		damon_for_each_region(r, t)
+			r->nr_accesses = 0;
+	}
+}
+
+/*
  * Check whether it is time to check and apply the target monitoring regions
  *
  * Returns true if it is.
@@ -238,6 +360,7 @@ static bool kdamond_need_update_primitiv
  */
 static bool kdamond_need_stop(struct damon_ctx *ctx)
 {
+	struct damon_target *t;
 	bool stop;
 
 	mutex_lock(&ctx->kdamond_lock);
@@ -249,7 +372,12 @@ static bool kdamond_need_stop(struct dam
 	if (!ctx->primitive.target_valid)
 		return false;
 
-	return !ctx->primitive.target_valid(ctx->target);
+	damon_for_each_target(t, ctx) {
+		if (ctx->primitive.target_valid(t))
+			return false;
+	}
+
+	return true;
 }
 
 static void set_kdamond_stop(struct damon_ctx *ctx)
@@ -265,6 +393,8 @@ static void set_kdamond_stop(struct damo
 static int kdamond_fn(void *data)
 {
 	struct damon_ctx *ctx = (struct damon_ctx *)data;
+	struct damon_target *t;
+	struct damon_region *r, *next;
 
 	mutex_lock(&ctx->kdamond_lock);
 	pr_info("kdamond (%d) starts\n", ctx->kdamond->pid);
@@ -291,6 +421,7 @@ static int kdamond_fn(void *data)
 			if (ctx->callback.after_aggregation &&
 					ctx->callback.after_aggregation(ctx))
 				set_kdamond_stop(ctx);
+			kdamond_reset_aggregated(ctx);
 			if (ctx->primitive.reset_aggregated)
 				ctx->primitive.reset_aggregated(ctx);
 		}
@@ -300,6 +431,10 @@ static int kdamond_fn(void *data)
 				ctx->primitive.update(ctx);
 		}
 	}
+	damon_for_each_target(t, ctx) {
+		damon_for_each_region_safe(r, next, t)
+			damon_destroy_region(r);
+	}
 
 	if (ctx->callback.before_terminate &&
 			ctx->callback.before_terminate(ctx))
