1 files changed, 527 insertions, 304 deletions

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 58145d59881d..e2bd2d7becdd 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -212,6 +212,7 @@ struct damon_sysfs_target {
 	struct kobject kobj;
 	struct damon_sysfs_regions *regions;
 	int pid;
+	bool obsolete;
 };
 
 static struct damon_sysfs_target *damon_sysfs_target_alloc(void)
@@ -263,6 +264,29 @@ static ssize_t pid_target_store(struct kobject *kobj,
 	return count;
 }
 
+static ssize_t obsolete_target_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_target *target = container_of(kobj,
+			struct damon_sysfs_target, kobj);
+
+	return sysfs_emit(buf, "%c\n", target->obsolete ? 'Y' : 'N');
+}
+
+static ssize_t obsolete_target_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_target *target = container_of(kobj,
+			struct damon_sysfs_target, kobj);
+	bool obsolete;
+	int err = kstrtobool(buf, &obsolete);
+
+	if (err)
+		return err;
+	target->obsolete = obsolete;
+	return count;
+}
+
 static void damon_sysfs_target_release(struct kobject *kobj)
 {
 	kfree(container_of(kobj, struct damon_sysfs_target, kobj));
@@ -271,8 +295,12 @@ static void damon_sysfs_target_release(struct kobject *kobj)
 static struct kobj_attribute damon_sysfs_target_pid_attr =
 		__ATTR_RW_MODE(pid_target, 0600);
 
+static struct kobj_attribute damon_sysfs_target_obsolete_attr =
+		__ATTR_RW_MODE(obsolete_target, 0600);
+
 static struct attribute *damon_sysfs_target_attrs[] = {
 	&damon_sysfs_target_pid_attr.attr,
+	&damon_sysfs_target_obsolete_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(damon_sysfs_target);
@@ -409,6 +437,164 @@ static const struct kobj_type damon_sysfs_targets_ktype = {
 };
 
 /*
+ * intervals goal directory
+ */
+
+struct damon_sysfs_intervals_goal {
+	struct kobject kobj;
+	unsigned long access_bp;
+	unsigned long aggrs;
+	unsigned long min_sample_us;
+	unsigned long max_sample_us;
+};
+
+static struct damon_sysfs_intervals_goal *damon_sysfs_intervals_goal_alloc(
+		unsigned long access_bp, unsigned long aggrs,
+		unsigned long min_sample_us, unsigned long max_sample_us)
+{
+	struct damon_sysfs_intervals_goal *goal = kmalloc(sizeof(*goal),
+			GFP_KERNEL);
+
+	if (!goal)
+		return NULL;
+
+	goal->kobj = (struct kobject){};
+	goal->access_bp = access_bp;
+	goal->aggrs = aggrs;
+	goal->min_sample_us = min_sample_us;
+	goal->max_sample_us = max_sample_us;
+	return goal;
+}
+
+static ssize_t access_bp_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+
+	return sysfs_emit(buf, "%lu\n", goal->access_bp);
+}
+
+static ssize_t access_bp_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+	unsigned long nr;
+	int err = kstrtoul(buf, 0, &nr);
+
+	if (err)
+		return err;
+
+	goal->access_bp = nr;
+	return count;
+}
+
+static ssize_t aggrs_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+
+	return sysfs_emit(buf, "%lu\n", goal->aggrs);
+}
+
+static ssize_t aggrs_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+	unsigned long nr;
+	int err = kstrtoul(buf, 0, &nr);
+
+	if (err)
+		return err;
+
+	goal->aggrs = nr;
+	return count;
+}
+
+static ssize_t min_sample_us_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+
+	return sysfs_emit(buf, "%lu\n", goal->min_sample_us);
+}
+
+static ssize_t min_sample_us_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+	unsigned long nr;
+	int err = kstrtoul(buf, 0, &nr);
+
+	if (err)
+		return err;
+
+	goal->min_sample_us = nr;
+	return count;
+}
+
+static ssize_t max_sample_us_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+
+	return sysfs_emit(buf, "%lu\n", goal->max_sample_us);
+}
+
+static ssize_t max_sample_us_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
+			struct damon_sysfs_intervals_goal, kobj);
+	unsigned long nr;
+	int err = kstrtoul(buf, 0, &nr);
+
+	if (err)
+		return err;
+
+	goal->max_sample_us = nr;
+	return count;
+}
+
+static void damon_sysfs_intervals_goal_release(struct kobject *kobj)
+{
+	kfree(container_of(kobj, struct damon_sysfs_intervals_goal, kobj));
+}
+
+static struct kobj_attribute damon_sysfs_intervals_goal_access_bp_attr =
+		__ATTR_RW_MODE(access_bp, 0600);
+
+static struct kobj_attribute damon_sysfs_intervals_goal_aggrs_attr =
+		__ATTR_RW_MODE(aggrs, 0600);
+
+static struct kobj_attribute damon_sysfs_intervals_goal_min_sample_us_attr =
+		__ATTR_RW_MODE(min_sample_us, 0600);
+
+static struct kobj_attribute damon_sysfs_intervals_goal_max_sample_us_attr =
+		__ATTR_RW_MODE(max_sample_us, 0600);
+
+static struct attribute *damon_sysfs_intervals_goal_attrs[] = {
+	&damon_sysfs_intervals_goal_access_bp_attr.attr,
+	&damon_sysfs_intervals_goal_aggrs_attr.attr,
+	&damon_sysfs_intervals_goal_min_sample_us_attr.attr,
+	&damon_sysfs_intervals_goal_max_sample_us_attr.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(damon_sysfs_intervals_goal);
+
+static const struct kobj_type damon_sysfs_intervals_goal_ktype = {
+	.release = damon_sysfs_intervals_goal_release,
+	.sysfs_ops = &kobj_sysfs_ops,
+	.default_groups = damon_sysfs_intervals_goal_groups,
+};
+
+/*
  * intervals directory
  */
 
@@ -417,6 +603,7 @@ struct damon_sysfs_intervals {
 	unsigned long sample_us;
 	unsigned long aggr_us;
 	unsigned long update_us;
+	struct damon_sysfs_intervals_goal *intervals_goal;
 };
 
 static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc(
@@ -436,6 +623,32 @@ static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc(
 	return intervals;
 }
 
+static int damon_sysfs_intervals_add_dirs(struct damon_sysfs_intervals *intervals)
+{
+	struct damon_sysfs_intervals_goal *goal;
+	int err;
+
+	goal = damon_sysfs_intervals_goal_alloc(0, 0, 0, 0);
+	if (!goal)
+		return -ENOMEM;
+
+	err = kobject_init_and_add(&goal->kobj,
+			&damon_sysfs_intervals_goal_ktype, &intervals->kobj,
+			"intervals_goal");
+	if (err) {
+		kobject_put(&goal->kobj);
+		intervals->intervals_goal = NULL;
+		return err;
+	}
+	intervals->intervals_goal = goal;
+	return 0;
+}
+
+static void damon_sysfs_intervals_rm_dirs(struct damon_sysfs_intervals *intervals)
+{
+	kobject_put(&intervals->intervals_goal->kobj);
+}
+
 static ssize_t sample_us_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
@@ -571,6 +784,9 @@ static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs)
 			"intervals");
 	if (err)
 		goto put_intervals_out;
+	err = damon_sysfs_intervals_add_dirs(intervals);
+	if (err)
+		goto put_intervals_out;
 	attrs->intervals = intervals;
 
 	nr_regions_range = damon_sysfs_ul_range_alloc(10, 1000);
@@ -599,6 +815,7 @@ put_intervals_out:
 static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs)
 {
 	kobject_put(&attrs->nr_regions_range->kobj);
+	damon_sysfs_intervals_rm_dirs(attrs->intervals);
 	kobject_put(&attrs->intervals->kobj);
 }
 
@@ -622,16 +839,30 @@ static const struct kobj_type damon_sysfs_attrs_ktype = {
  * context directory
  */
 
-/* This should match with enum damon_ops_id */
-static const char * const damon_sysfs_ops_strs[] = {
-	"vaddr",
-	"fvaddr",
-	"paddr",
+struct damon_sysfs_ops_name {
+	enum damon_ops_id ops_id;
+	char *name;
+};
+
+static const struct damon_sysfs_ops_name damon_sysfs_ops_names[] = {
+	{
+		.ops_id = DAMON_OPS_VADDR,
+		.name = "vaddr",
+	},
+	{
+		.ops_id = DAMON_OPS_FVADDR,
+		.name = "fvaddr",
+	},
+	{
+		.ops_id = DAMON_OPS_PADDR,
+		.name = "paddr",
+	},
 };
 
 struct damon_sysfs_context {
 	struct kobject kobj;
 	enum damon_ops_id ops_id;
+	unsigned long addr_unit;
 	struct damon_sysfs_attrs *attrs;
 	struct damon_sysfs_targets *targets;
 	struct damon_sysfs_schemes *schemes;
@@ -647,6 +878,7 @@ static struct damon_sysfs_context *damon_sysfs_context_alloc(
 		return NULL;
 	context->kobj = (struct kobject){};
 	context->ops_id = ops_id;
+	context->addr_unit = 1;
 	return context;
 }
 
@@ -745,14 +977,16 @@ static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context)
 static ssize_t avail_operations_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
-	enum damon_ops_id id;
 	int len = 0;
+	int i;
 
-	for (id = 0; id < NR_DAMON_OPS; id++) {
-		if (!damon_is_registered_ops(id))
+	for (i = 0; i < ARRAY_SIZE(damon_sysfs_ops_names); i++) {
+		const struct damon_sysfs_ops_name *ops_name;
+
+		ops_name = &damon_sysfs_ops_names[i];
+		if (!damon_is_registered_ops(ops_name->ops_id))
 			continue;
-		len += sysfs_emit_at(buf, len, "%s\n",
-				damon_sysfs_ops_strs[id]);
+		len += sysfs_emit_at(buf, len, "%s\n", ops_name->name);
 	}
 	return len;
 }
@@ -762,8 +996,16 @@ static ssize_t operations_show(struct kobject *kobj,
 {
 	struct damon_sysfs_context *context = container_of(kobj,
 			struct damon_sysfs_context, kobj);
+	int i;
 
-	return sysfs_emit(buf, "%s\n", damon_sysfs_ops_strs[context->ops_id]);
+	for (i = 0; i < ARRAY_SIZE(damon_sysfs_ops_names); i++) {
+		const struct damon_sysfs_ops_name *ops_name;
+
+		ops_name = &damon_sysfs_ops_names[i];
+		if (ops_name->ops_id == context->ops_id)
+			return sysfs_emit(buf, "%s\n", ops_name->name);
+	}
+	return -EINVAL;
 }
 
 static ssize_t operations_store(struct kobject *kobj,
@@ -771,17 +1013,46 @@ static ssize_t operations_store(struct kobject *kobj,
 {
 	struct damon_sysfs_context *context = container_of(kobj,
 			struct damon_sysfs_context, kobj);
-	enum damon_ops_id id;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(damon_sysfs_ops_names); i++) {
+		const struct damon_sysfs_ops_name *ops_name;
 
-	for (id = 0; id < NR_DAMON_OPS; id++) {
-		if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) {
-			context->ops_id = id;
+		ops_name = &damon_sysfs_ops_names[i];
+		if (sysfs_streq(buf, ops_name->name)) {
+			context->ops_id = ops_name->ops_id;
 			return count;
 		}
 	}
 	return -EINVAL;
 }
 
+static ssize_t addr_unit_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_context *context = container_of(kobj,
+			struct damon_sysfs_context, kobj);
+
+	return sysfs_emit(buf, "%lu\n", context->addr_unit);
+}
+
+static ssize_t addr_unit_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_context *context = container_of(kobj,
+			struct damon_sysfs_context, kobj);
+	unsigned long input_addr_unit;
+	int err = kstrtoul(buf, 0, &input_addr_unit);
+
+	if (err)
+		return err;
+	if (!input_addr_unit)
+		return -EINVAL;
+
+	context->addr_unit = input_addr_unit;
+	return count;
+}
+
 static void damon_sysfs_context_release(struct kobject *kobj)
 {
 	kfree(container_of(kobj, struct damon_sysfs_context, kobj));
@@ -793,9 +1064,13 @@ static struct kobj_attribute damon_sysfs_context_avail_operations_attr =
 static struct kobj_attribute damon_sysfs_context_operations_attr =
 		__ATTR_RW_MODE(operations, 0600);
 
+static struct kobj_attribute damon_sysfs_context_addr_unit_attr =
+		__ATTR_RW_MODE(addr_unit, 0600);
+
 static struct attribute *damon_sysfs_context_attrs[] = {
 	&damon_sysfs_context_avail_operations_attr.attr,
 	&damon_sysfs_context_operations_attr.attr,
+	&damon_sysfs_context_addr_unit_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(damon_sysfs_context);
@@ -940,6 +1215,7 @@ struct damon_sysfs_kdamond {
 	struct kobject kobj;
 	struct damon_sysfs_contexts *contexts;
 	struct damon_ctx *damon_ctx;
+	unsigned int refresh_ms;
 };
 
 static struct damon_sysfs_kdamond *damon_sysfs_kdamond_alloc(void)
@@ -974,16 +1250,6 @@ static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond)
 	kobject_put(&kdamond->contexts->kobj);
 }
 
-static bool damon_sysfs_ctx_running(struct damon_ctx *ctx)
-{
-	bool running;
-
-	mutex_lock(&ctx->kdamond_lock);
-	running = ctx->kdamond != NULL;
-	mutex_unlock(&ctx->kdamond_lock);
-	return running;
-}
-
 /*
  * enum damon_sysfs_cmd - Commands for a specific kdamond.
  */
@@ -1025,6 +1291,11 @@ enum damon_sysfs_cmd {
 	 */
 	DAMON_SYSFS_CMD_UPDATE_SCHEMES_EFFECTIVE_QUOTAS,
 	/*
+	 * @DAMON_SYSFS_CMD_UPDATE_TUNED_INTERVALS: Update the tuned monitoring
+	 * intervals.
+	 */
+	DAMON_SYSFS_CMD_UPDATE_TUNED_INTERVALS,
+	/*
 	 * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands.
 	 */
 	NR_DAMON_SYSFS_CMDS,
@@ -1041,39 +1312,25 @@ static const char * const damon_sysfs_cmd_strs[] = {
 	"update_schemes_tried_regions",
 	"clear_schemes_tried_regions",
 	"update_schemes_effective_quotas",
+	"update_tuned_intervals",
 };
 
-/*
- * struct damon_sysfs_cmd_request - A request to the DAMON callback.
- * @cmd:	The command that needs to be handled by the callback.
- * @kdamond:	The kobject wrapper that associated to the kdamond thread.
- *
- * This structure represents a sysfs command request that need to access some
- * DAMON context-internal data.  Because DAMON context-internal data can be
- * safely accessed from DAMON callbacks without additional synchronization, the
- * request will be handled by the DAMON callback.  None-``NULL`` @kdamond means
- * the request is valid.
- */
-struct damon_sysfs_cmd_request {
-	enum damon_sysfs_cmd cmd;
-	struct damon_sysfs_kdamond *kdamond;
-};
-
-/* Current DAMON callback request.  Protected by damon_sysfs_lock. */
-static struct damon_sysfs_cmd_request damon_sysfs_cmd_request;
-
 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
 		char *buf)
 {
 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
 			struct damon_sysfs_kdamond, kobj);
-	struct damon_ctx *ctx = kdamond->damon_ctx;
-	bool running;
+	struct damon_ctx *ctx;
+	bool running = false;
 
-	if (!ctx)
-		running = false;
-	else
-		running = damon_sysfs_ctx_running(ctx);
+	if (!mutex_trylock(&damon_sysfs_lock))
+		return -EBUSY;
+
+	ctx = kdamond->damon_ctx;
+	if (ctx)
+		running = damon_is_running(ctx);
+
+	mutex_unlock(&damon_sysfs_lock);
 
 	return sysfs_emit(buf, "%s\n", running ?
 			damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] :
@@ -1084,11 +1341,18 @@ static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
 		struct damon_sysfs_attrs *sys_attrs)
 {
 	struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals;
+	struct damon_sysfs_intervals_goal *sys_goal =
+		sys_intervals->intervals_goal;
 	struct damon_sysfs_ul_range *sys_nr_regions =
 		sys_attrs->nr_regions_range;
 	struct damon_attrs attrs = {
 		.sample_interval = sys_intervals->sample_us,
 		.aggr_interval = sys_intervals->aggr_us,
+		.intervals_goal = {
+			.access_bp = sys_goal->access_bp,
+			.aggrs = sys_goal->aggrs,
+			.min_sample_us = sys_goal->min_sample_us,
+			.max_sample_us = sys_goal->max_sample_us},
 		.ops_update_interval = sys_intervals->update_us,
 		.min_nr_regions = sys_nr_regions->min,
 		.max_nr_regions = sys_nr_regions->max,
@@ -1096,20 +1360,9 @@ static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
 	return damon_set_attrs(ctx, &attrs);
 }
 
-static void damon_sysfs_destroy_targets(struct damon_ctx *ctx)
-{
-	struct damon_target *t, *next;
-	bool has_pid = damon_target_has_pid(ctx);
-
-	damon_for_each_target_safe(t, next, ctx) {
-		if (has_pid)
-			put_pid(t->pid);
-		damon_destroy_target(t);
-	}
-}
-
 static int damon_sysfs_set_regions(struct damon_target *t,
-		struct damon_sysfs_regions *sysfs_regions)
+		struct damon_sysfs_regions *sysfs_regions,
+		unsigned long min_sz_region)
 {
 	struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr,
 			sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN);
@@ -1131,7 +1384,7 @@ static int damon_sysfs_set_regions(struct damon_target *t,
 		if (ranges[i - 1].end > ranges[i].start)
 			goto out;
 	}
-	err = damon_set_regions(t, ranges, sysfs_regions->nr);
+	err = damon_set_regions(t, ranges, sysfs_regions->nr, min_sz_region);
 out:
 	kfree(ranges);
 	return err;
@@ -1142,7 +1395,6 @@ static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target,
 		struct damon_ctx *ctx)
 {
 	struct damon_target *t = damon_new_target();
-	int err = -EINVAL;
 
 	if (!t)
 		return -ENOMEM;
@@ -1150,16 +1402,11 @@ static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target,
 	if (damon_target_has_pid(ctx)) {
 		t->pid = find_get_pid(sys_target->pid);
 		if (!t->pid)
-			goto destroy_targets_out;
+			/* caller will destroy targets */
+			return -EINVAL;
 	}
-	err = damon_sysfs_set_regions(t, sys_target->regions);
-	if (err)
-		goto destroy_targets_out;
-	return 0;
-
-destroy_targets_out:
-	damon_sysfs_destroy_targets(ctx);
-	return err;
+	t->obsolete = sys_target->obsolete;
+	return damon_sysfs_set_regions(t, sys_target->regions, ctx->min_sz_region);
 }
 
 static int damon_sysfs_add_targets(struct damon_ctx *ctx,
@@ -1181,95 +1428,31 @@ static int damon_sysfs_add_targets(struct damon_ctx *ctx,
 	return 0;
 }
 
-static bool damon_sysfs_schemes_regions_updating;
-
-static void damon_sysfs_before_terminate(struct damon_ctx *ctx)
-{
-	struct damon_target *t, *next;
-	struct damon_sysfs_kdamond *kdamond;
-	enum damon_sysfs_cmd cmd;
-
-	/* damon_sysfs_schemes_update_regions_stop() might not yet called */
-	kdamond = damon_sysfs_cmd_request.kdamond;
-	cmd = damon_sysfs_cmd_request.cmd;
-	if (kdamond && ctx == kdamond->damon_ctx &&
-			(cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS ||
-			 cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES) &&
-			damon_sysfs_schemes_regions_updating) {
-		damon_sysfs_schemes_update_regions_stop(ctx);
-		damon_sysfs_schemes_regions_updating = false;
-		mutex_unlock(&damon_sysfs_lock);
-	}
-
-	if (!damon_target_has_pid(ctx))
-		return;
-
-	mutex_lock(&ctx->kdamond_lock);
-	damon_for_each_target_safe(t, next, ctx) {
-		put_pid(t->pid);
-		damon_destroy_target(t);
-	}
-	mutex_unlock(&ctx->kdamond_lock);
-}
-
 /*
  * damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files.
- * @kdamond:	The kobject wrapper that associated to the kdamond thread.
+ * @data:	The kobject wrapper that associated to the kdamond thread.
  *
  * This function reads the schemes stats of specific kdamond and update the
  * related values for sysfs files.  This function should be called from DAMON
- * callbacks while holding ``damon_syfs_lock``, to safely access the DAMON
- * contexts-internal data and DAMON sysfs variables.
+ * worker thread,to safely access the DAMON contexts-internal data.  Caller
+ * should also ensure holding ``damon_syfs_lock``, and ->damon_ctx of @data is
+ * not NULL but a valid pointer, to safely access DAMON sysfs variables.
  */
-static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond)
+static int damon_sysfs_upd_schemes_stats(void *data)
 {
+	struct damon_sysfs_kdamond *kdamond = data;
 	struct damon_ctx *ctx = kdamond->damon_ctx;
 
-	if (!ctx)
-		return -EINVAL;
 	damon_sysfs_schemes_update_stats(
 			kdamond->contexts->contexts_arr[0]->schemes, ctx);
 	return 0;
 }
 
-static int damon_sysfs_upd_schemes_regions_start(
-		struct damon_sysfs_kdamond *kdamond, bool total_bytes_only)
-{
-	struct damon_ctx *ctx = kdamond->damon_ctx;
-
-	if (!ctx)
-		return -EINVAL;
-	return damon_sysfs_schemes_update_regions_start(
-			kdamond->contexts->contexts_arr[0]->schemes, ctx,
-			total_bytes_only);
-}
-
-static int damon_sysfs_upd_schemes_regions_stop(
-		struct damon_sysfs_kdamond *kdamond)
-{
-	struct damon_ctx *ctx = kdamond->damon_ctx;
-
-	if (!ctx)
-		return -EINVAL;
-	return damon_sysfs_schemes_update_regions_stop(ctx);
-}
-
-static int damon_sysfs_clear_schemes_regions(
-		struct damon_sysfs_kdamond *kdamond)
-{
-	struct damon_ctx *ctx = kdamond->damon_ctx;
-
-	if (!ctx)
-		return -EINVAL;
-	return damon_sysfs_schemes_clear_regions(
-			kdamond->contexts->contexts_arr[0]->schemes, ctx);
-}
-
 static inline bool damon_sysfs_kdamond_running(
 		struct damon_sysfs_kdamond *kdamond)
 {
 	return kdamond->damon_ctx &&
-		damon_sysfs_ctx_running(kdamond->damon_ctx);
+		damon_is_running(kdamond->damon_ctx);
 }
 
 static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,
@@ -1280,6 +1463,11 @@ static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,
 	err = damon_select_ops(ctx, sys_ctx->ops_id);
 	if (err)
 		return err;
+	ctx->addr_unit = sys_ctx->addr_unit;
+	/* addr_unit is respected by only DAMON_OPS_PADDR */
+	if (sys_ctx->ops_id == DAMON_OPS_PADDR)
+		ctx->min_sz_region = max(
+				DAMON_MIN_REGION / sys_ctx->addr_unit, 1);
 	err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs);
 	if (err)
 		return err;
@@ -1293,14 +1481,35 @@ static struct damon_ctx *damon_sysfs_build_ctx(
 		struct damon_sysfs_context *sys_ctx);
 
 /*
+ * Return a new damon_ctx for testing new parameters to commit.
+ */
+static struct damon_ctx *damon_sysfs_new_test_ctx(
+		struct damon_ctx *running_ctx)
+{
+	struct damon_ctx *test_ctx;
+	int err;
+
+	test_ctx = damon_new_ctx();
+	if (!test_ctx)
+		return NULL;
+	err = damon_commit_ctx(test_ctx, running_ctx);
+	if (err) {
+		damon_destroy_ctx(test_ctx);
+		return NULL;
+	}
+	return test_ctx;
+}
+
+/*
  * damon_sysfs_commit_input() - Commit user inputs to a running kdamond.
  * @kdamond:	The kobject wrapper for the associated kdamond.
  *
- * If the sysfs input is wrong, the kdamond will be terminated.
+ * Returns error if the sysfs input is wrong.
  */
-static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond)
+static int damon_sysfs_commit_input(void *data)
 {
-	struct damon_ctx *param_ctx;
+	struct damon_sysfs_kdamond *kdamond = data;
+	struct damon_ctx *param_ctx, *test_ctx;
 	int err;
 
 	if (!damon_sysfs_kdamond_running(kdamond))
@@ -1312,15 +1521,22 @@ static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond)
 	param_ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]);
 	if (IS_ERR(param_ctx))
 		return PTR_ERR(param_ctx);
+	test_ctx = damon_sysfs_new_test_ctx(kdamond->damon_ctx);
+	if (!test_ctx)
+		return -ENOMEM;
+	err = damon_commit_ctx(test_ctx, param_ctx);
+	if (err)
+		goto out;
 	err = damon_commit_ctx(kdamond->damon_ctx, param_ctx);
-	damon_sysfs_destroy_targets(param_ctx);
+out:
+	damon_destroy_ctx(test_ctx);
 	damon_destroy_ctx(param_ctx);
 	return err;
 }
 
-static int damon_sysfs_commit_schemes_quota_goals(
-		struct damon_sysfs_kdamond *sysfs_kdamond)
+static int damon_sysfs_commit_schemes_quota_goals(void *data)
 {
+	struct damon_sysfs_kdamond *sysfs_kdamond = data;
 	struct damon_ctx *ctx;
 	struct damon_sysfs_context *sysfs_ctx;
 
@@ -1338,128 +1554,33 @@ static int damon_sysfs_commit_schemes_quota_goals(
 /*
  * damon_sysfs_upd_schemes_effective_quotas() - Update schemes effective quotas
  * sysfs files.
- * @kdamond:	The kobject wrapper that associated to the kdamond thread.
+ * @data:	The kobject wrapper that associated to the kdamond thread.
  *
  * This function reads the schemes' effective quotas of specific kdamond and
  * update the related values for sysfs files.  This function should be called
  * from DAMON callbacks while holding ``damon_syfs_lock``, to safely access the
  * DAMON contexts-internal data and DAMON sysfs variables.
  */
-static int damon_sysfs_upd_schemes_effective_quotas(
-		struct damon_sysfs_kdamond *kdamond)
+static int damon_sysfs_upd_schemes_effective_quotas(void *data)
 {
+	struct damon_sysfs_kdamond *kdamond = data;
 	struct damon_ctx *ctx = kdamond->damon_ctx;
 
-	if (!ctx)
-		return -EINVAL;
 	damos_sysfs_update_effective_quotas(
 			kdamond->contexts->contexts_arr[0]->schemes, ctx);
 	return 0;
 }
 
-
-/*
- * damon_sysfs_cmd_request_callback() - DAMON callback for handling requests.
- * @c:		The DAMON context of the callback.
- * @active:	Whether @c is not deactivated due to watermarks.
- * @after_aggr:	Whether this is called from after_aggregation() callback.
- *
- * This function is periodically called back from the kdamond thread for @c.
- * Then, it checks if there is a waiting DAMON sysfs request and handles it.
- */
-static int damon_sysfs_cmd_request_callback(struct damon_ctx *c, bool active,
-		bool after_aggregation)
-{
-	struct damon_sysfs_kdamond *kdamond;
-	bool total_bytes_only = false;
-	int err = 0;
-
-	/* avoid deadlock due to concurrent state_store('off') */
-	if (!damon_sysfs_schemes_regions_updating &&
-			!mutex_trylock(&damon_sysfs_lock))
-		return 0;
-	kdamond = damon_sysfs_cmd_request.kdamond;
-	if (!kdamond || kdamond->damon_ctx != c)
-		goto out;
-	switch (damon_sysfs_cmd_request.cmd) {
-	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS:
-		err = damon_sysfs_upd_schemes_stats(kdamond);
-		break;
-	case DAMON_SYSFS_CMD_COMMIT:
-		if (!after_aggregation)
-			goto out;
-		err = damon_sysfs_commit_input(kdamond);
-		break;
-	case DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS:
-		err = damon_sysfs_commit_schemes_quota_goals(kdamond);
-		break;
-	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES:
-		total_bytes_only = true;
-		fallthrough;
-	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS:
-		if (!damon_sysfs_schemes_regions_updating) {
-			err = damon_sysfs_upd_schemes_regions_start(kdamond,
-					total_bytes_only);
-			if (!err) {
-				damon_sysfs_schemes_regions_updating = true;
-				goto keep_lock_out;
-			}
-		} else {
-			damos_sysfs_mark_finished_regions_updates(c);
-			/*
-			 * Continue regions updating if DAMON is till
-			 * active and the update for all schemes is not
-			 * finished.
-			 */
-			if (active && !damos_sysfs_regions_upd_done())
-				goto keep_lock_out;
-			err = damon_sysfs_upd_schemes_regions_stop(kdamond);
-			damon_sysfs_schemes_regions_updating = false;
-		}
-		break;
-	case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS:
-		err = damon_sysfs_clear_schemes_regions(kdamond);
-		break;
-	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_EFFECTIVE_QUOTAS:
-		err = damon_sysfs_upd_schemes_effective_quotas(kdamond);
-		break;
-	default:
-		break;
-	}
-	/* Mark the request as invalid now. */
-	damon_sysfs_cmd_request.kdamond = NULL;
-out:
-	if (!damon_sysfs_schemes_regions_updating)
-		mutex_unlock(&damon_sysfs_lock);
-keep_lock_out:
-	return err;
-}
-
-static int damon_sysfs_after_wmarks_check(struct damon_ctx *c)
-{
-	/*
-	 * after_wmarks_check() is called back while the context is deactivated
-	 * by watermarks.
-	 */
-	return damon_sysfs_cmd_request_callback(c, false, false);
-}
-
-static int damon_sysfs_after_sampling(struct damon_ctx *c)
+static int damon_sysfs_upd_tuned_intervals(void *data)
 {
-	/*
-	 * after_sampling() is called back only while the context is not
-	 * deactivated by watermarks.
-	 */
-	return damon_sysfs_cmd_request_callback(c, true, false);
-}
+	struct damon_sysfs_kdamond *kdamond = data;
+	struct damon_ctx *ctx = kdamond->damon_ctx;
 
-static int damon_sysfs_after_aggregation(struct damon_ctx *c)
-{
-	/*
-	 * after_aggregation() is called back only while the context is not
-	 * deactivated by watermarks.
-	 */
-	return damon_sysfs_cmd_request_callback(c, true, true);
+	kdamond->contexts->contexts_arr[0]->attrs->intervals->sample_us =
+		ctx->attrs.sample_interval;
+	kdamond->contexts->contexts_arr[0]->attrs->intervals->aggr_us =
+		ctx->attrs.aggr_interval;
+	return 0;
 }
 
 static struct damon_ctx *damon_sysfs_build_ctx(
@@ -1477,22 +1598,39 @@ static struct damon_ctx *damon_sysfs_build_ctx(
 		return ERR_PTR(err);
 	}
 
-	ctx->callback.after_wmarks_check = damon_sysfs_after_wmarks_check;
-	ctx->callback.after_sampling = damon_sysfs_after_sampling;
-	ctx->callback.after_aggregation = damon_sysfs_after_aggregation;
-	ctx->callback.before_terminate = damon_sysfs_before_terminate;
 	return ctx;
 }
 
+static unsigned long damon_sysfs_next_update_jiffies;
+
+static int damon_sysfs_repeat_call_fn(void *data)
+{
+	struct damon_sysfs_kdamond *sysfs_kdamond = data;
+
+	if (!sysfs_kdamond->refresh_ms)
+		return 0;
+	if (time_before(jiffies, damon_sysfs_next_update_jiffies))
+		return 0;
+	damon_sysfs_next_update_jiffies = jiffies +
+		msecs_to_jiffies(sysfs_kdamond->refresh_ms);
+
+	if (!mutex_trylock(&damon_sysfs_lock))
+		return 0;
+	damon_sysfs_upd_tuned_intervals(sysfs_kdamond);
+	damon_sysfs_upd_schemes_stats(sysfs_kdamond);
+	damon_sysfs_upd_schemes_effective_quotas(sysfs_kdamond);
+	mutex_unlock(&damon_sysfs_lock);
+	return 0;
+}
+
 static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond)
 {
 	struct damon_ctx *ctx;
+	struct damon_call_control *repeat_call_control;
 	int err;
 
 	if (damon_sysfs_kdamond_running(kdamond))
 		return -EBUSY;
-	if (damon_sysfs_cmd_request.kdamond == kdamond)
-		return -EBUSY;
 	/* TODO: support multiple contexts per kdamond */
 	if (kdamond->contexts->nr != 1)
 		return -EINVAL;
@@ -1501,15 +1639,32 @@ static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond)
 		damon_destroy_ctx(kdamond->damon_ctx);
 	kdamond->damon_ctx = NULL;
 
+	repeat_call_control = kmalloc(sizeof(*repeat_call_control),
+			GFP_KERNEL);
+	if (!repeat_call_control)
+		return -ENOMEM;
+
 	ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]);
-	if (IS_ERR(ctx))
+	if (IS_ERR(ctx)) {
+		kfree(repeat_call_control);
 		return PTR_ERR(ctx);
+	}
 	err = damon_start(&ctx, 1, false);
 	if (err) {
+		kfree(repeat_call_control);
 		damon_destroy_ctx(ctx);
 		return err;
 	}
 	kdamond->damon_ctx = ctx;
+
+	damon_sysfs_next_update_jiffies =
+		jiffies + msecs_to_jiffies(kdamond->refresh_ms);
+
+	repeat_call_control->fn = damon_sysfs_repeat_call_fn;
+	repeat_call_control->data = kdamond;
+	repeat_call_control->repeat = true;
+	repeat_call_control->dealloc_on_cancel = true;
+	damon_call(ctx, repeat_call_control);
 	return err;
 }
 
@@ -1525,63 +1680,104 @@ static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond)
 	 */
 }
 
+static int damon_sysfs_damon_call(int (*fn)(void *data),
+		struct damon_sysfs_kdamond *kdamond)
+{
+	struct damon_call_control call_control = {};
+	int err;
+
+	if (!kdamond->damon_ctx)
+		return -EINVAL;
+	call_control.fn = fn;
+	call_control.data = kdamond;
+	err = damon_call(kdamond->damon_ctx, &call_control);
+	return err ? err : call_control.return_code;
+}
+
+struct damon_sysfs_schemes_walk_data {
+	struct damon_sysfs_kdamond *sysfs_kdamond;
+	bool total_bytes_only;
+};
+
+/* populate the region directory */
+static void damon_sysfs_schemes_tried_regions_upd_one(void *data, struct damon_ctx *ctx,
+		struct damon_target *t, struct damon_region *r,
+		struct damos *s, unsigned long sz_filter_passed)
+{
+	struct damon_sysfs_schemes_walk_data *walk_data = data;
+	struct damon_sysfs_kdamond *sysfs_kdamond = walk_data->sysfs_kdamond;
+
+	damos_sysfs_populate_region_dir(
+			sysfs_kdamond->contexts->contexts_arr[0]->schemes,
+			ctx, t, r, s, walk_data->total_bytes_only,
+			sz_filter_passed);
+}
+
+static int damon_sysfs_update_schemes_tried_regions(
+		struct damon_sysfs_kdamond *sysfs_kdamond, bool total_bytes_only)
+{
+	struct damon_sysfs_schemes_walk_data walk_data = {
+		.sysfs_kdamond = sysfs_kdamond,
+		.total_bytes_only = total_bytes_only,
+	};
+	struct damos_walk_control control = {
+		.walk_fn = damon_sysfs_schemes_tried_regions_upd_one,
+		.data = &walk_data,
+	};
+	struct damon_ctx *ctx = sysfs_kdamond->damon_ctx;
+
+	if (!ctx)
+		return -EINVAL;
+
+	damon_sysfs_schemes_clear_regions(
+			sysfs_kdamond->contexts->contexts_arr[0]->schemes);
+	return damos_walk(ctx, &control);
+}
+
 /*
  * damon_sysfs_handle_cmd() - Handle a command for a specific kdamond.
  * @cmd:	The command to handle.
  * @kdamond:	The kobject wrapper for the associated kdamond.
  *
- * This function handles a DAMON sysfs command for a kdamond.  For commands
- * that need to access running DAMON context-internal data, it requests
- * handling of the command to the DAMON callback
- * (@damon_sysfs_cmd_request_callback()) and wait until it is properly handled,
- * or the context is completed.
+ * This function handles a DAMON sysfs command for a kdamond.
  *
  * Return: 0 on success, negative error code otherwise.
  */
 static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd,
 		struct damon_sysfs_kdamond *kdamond)
 {
-	bool need_wait = true;
-
-	/* Handle commands that doesn't access DAMON context-internal data */
 	switch (cmd) {
 	case DAMON_SYSFS_CMD_ON:
 		return damon_sysfs_turn_damon_on(kdamond);
 	case DAMON_SYSFS_CMD_OFF:
 		return damon_sysfs_turn_damon_off(kdamond);
+	case DAMON_SYSFS_CMD_COMMIT:
+		return damon_sysfs_damon_call(
+				damon_sysfs_commit_input, kdamond);
+	case DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS:
+		return damon_sysfs_damon_call(
+				damon_sysfs_commit_schemes_quota_goals,
+				kdamond);
+	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS:
+		return damon_sysfs_damon_call(
+				damon_sysfs_upd_schemes_stats, kdamond);
+	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES:
+		return damon_sysfs_update_schemes_tried_regions(kdamond, true);
+	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS:
+		return damon_sysfs_update_schemes_tried_regions(kdamond, false);
+	case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS:
+		return damon_sysfs_schemes_clear_regions(
+			kdamond->contexts->contexts_arr[0]->schemes);
+	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_EFFECTIVE_QUOTAS:
+		return damon_sysfs_damon_call(
+				damon_sysfs_upd_schemes_effective_quotas,
+				kdamond);
+	case DAMON_SYSFS_CMD_UPDATE_TUNED_INTERVALS:
+		return damon_sysfs_damon_call(
+				damon_sysfs_upd_tuned_intervals, kdamond);
 	default:
-		break;
-	}
-
-	/* Pass the command to DAMON callback for safe DAMON context access */
-	if (damon_sysfs_cmd_request.kdamond)
-		return -EBUSY;
-	if (!damon_sysfs_kdamond_running(kdamond))
 		return -EINVAL;
-	damon_sysfs_cmd_request.cmd = cmd;
-	damon_sysfs_cmd_request.kdamond = kdamond;
-
-	/*
-	 * wait until damon_sysfs_cmd_request_callback() handles the request
-	 * from kdamond context
-	 */
-	mutex_unlock(&damon_sysfs_lock);
-	while (need_wait) {
-		schedule_timeout_idle(msecs_to_jiffies(100));
-		if (!mutex_trylock(&damon_sysfs_lock))
-			continue;
-		if (!damon_sysfs_cmd_request.kdamond) {
-			/* damon_sysfs_cmd_request_callback() handled */
-			need_wait = false;
-		} else if (!damon_sysfs_kdamond_running(kdamond)) {
-			/* kdamond has already finished */
-			need_wait = false;
-			damon_sysfs_cmd_request.kdamond = NULL;
-		}
-		mutex_unlock(&damon_sysfs_lock);
 	}
-	mutex_lock(&damon_sysfs_lock);
-	return 0;
 }
 
 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
@@ -1629,6 +1825,30 @@ out:
 	return sysfs_emit(buf, "%d\n", pid);
 }
 
+static ssize_t refresh_ms_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
+			struct damon_sysfs_kdamond, kobj);
+
+	return sysfs_emit(buf, "%u\n", kdamond->refresh_ms);
+}
+
+static ssize_t refresh_ms_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
+			struct damon_sysfs_kdamond, kobj);
+	unsigned int nr;
+	int err = kstrtouint(buf, 0, &nr);
+
+	if (err)
+		return err;
+
+	kdamond->refresh_ms = nr;
+	return count;
+}
+
 static void damon_sysfs_kdamond_release(struct kobject *kobj)
 {
 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
@@ -1645,9 +1865,13 @@ static struct kobj_attribute damon_sysfs_kdamond_state_attr =
 static struct kobj_attribute damon_sysfs_kdamond_pid_attr =
 		__ATTR_RO_MODE(pid, 0400);
 
+static struct kobj_attribute damon_sysfs_kdamond_refresh_ms_attr =
+		__ATTR_RW_MODE(refresh_ms, 0600);
+
 static struct attribute *damon_sysfs_kdamond_attrs[] = {
 	&damon_sysfs_kdamond_state_attr.attr,
 	&damon_sysfs_kdamond_pid_attr.attr,
+	&damon_sysfs_kdamond_refresh_ms_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(damon_sysfs_kdamond);
@@ -1693,8 +1917,7 @@ static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds,
 	int i;
 
 	for (i = 0; i < nr_kdamonds; i++) {
-		if (damon_sysfs_kdamond_running(kdamonds[i]) ||
-		    damon_sysfs_cmd_request.kdamond == kdamonds[i])
+		if (damon_sysfs_kdamond_running(kdamonds[i]))
 			return true;
 	}