1 files changed, 112 insertions, 1 deletions

diff --git a/mm/damon/core.c b/mm/damon/core.c
index ceec75b88ef9..d9ef62047bf5 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -263,6 +263,40 @@ int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges,
 	return 0;
 }
 
+struct damos_filter *damos_new_filter(enum damos_filter_type type,
+		bool matching)
+{
+	struct damos_filter *filter;
+
+	filter = kmalloc(sizeof(*filter), GFP_KERNEL);
+	if (!filter)
+		return NULL;
+	filter->type = type;
+	filter->matching = matching;
+	return filter;
+}
+
+void damos_add_filter(struct damos *s, struct damos_filter *f)
+{
+	list_add_tail(&f->list, &s->filters);
+}
+
+static void damos_del_filter(struct damos_filter *f)
+{
+	list_del(&f->list);
+}
+
+static void damos_free_filter(struct damos_filter *f)
+{
+	kfree(f);
+}
+
+void damos_destroy_filter(struct damos_filter *f)
+{
+	damos_del_filter(f);
+	damos_free_filter(f);
+}
+
 /* initialize private fields of damos_quota and return the pointer */
 static struct damos_quota *damos_quota_init_priv(struct damos_quota *quota)
 {
@@ -287,6 +321,7 @@ struct damos *damon_new_scheme(struct damos_access_pattern *pattern,
 		return NULL;
 	scheme->pattern = *pattern;
 	scheme->action = action;
+	INIT_LIST_HEAD(&scheme->filters);
 	scheme->stat = (struct damos_stat){};
 	INIT_LIST_HEAD(&scheme->list);
 
@@ -315,6 +350,10 @@ static void damon_free_scheme(struct damos *s)
 
 void damon_destroy_scheme(struct damos *s)
 {
+	struct damos_filter *f, *next;
+
+	damos_for_each_filter_safe(f, next, s)
+		damos_destroy_filter(f);
 	damon_del_scheme(s);
 	damon_free_scheme(s);
 }
@@ -426,6 +465,76 @@ void damon_destroy_ctx(struct damon_ctx *ctx)
 	kfree(ctx);
 }
 
+static unsigned int damon_age_for_new_attrs(unsigned int age,
+		struct damon_attrs *old_attrs, struct damon_attrs *new_attrs)
+{
+	return age * old_attrs->aggr_interval / new_attrs->aggr_interval;
+}
+
+/* convert access ratio in bp (per 10,000) to nr_accesses */
+static unsigned int damon_accesses_bp_to_nr_accesses(
+		unsigned int accesses_bp, struct damon_attrs *attrs)
+{
+	unsigned int max_nr_accesses =
+		attrs->aggr_interval / attrs->sample_interval;
+
+	return accesses_bp * max_nr_accesses / 10000;
+}
+
+/* convert nr_accesses to access ratio in bp (per 10,000) */
+static unsigned int damon_nr_accesses_to_accesses_bp(
+		unsigned int nr_accesses, struct damon_attrs *attrs)
+{
+	unsigned int max_nr_accesses =
+		attrs->aggr_interval / attrs->sample_interval;
+
+	return nr_accesses * 10000 / max_nr_accesses;
+}
+
+static unsigned int damon_nr_accesses_for_new_attrs(unsigned int nr_accesses,
+		struct damon_attrs *old_attrs, struct damon_attrs *new_attrs)
+{
+	return damon_accesses_bp_to_nr_accesses(
+			damon_nr_accesses_to_accesses_bp(
+				nr_accesses, old_attrs),
+			new_attrs);
+}
+
+static void damon_update_monitoring_result(struct damon_region *r,
+		struct damon_attrs *old_attrs, struct damon_attrs *new_attrs)
+{
+	r->nr_accesses = damon_nr_accesses_for_new_attrs(r->nr_accesses,
+			old_attrs, new_attrs);
+	r->age = damon_age_for_new_attrs(r->age, old_attrs, new_attrs);
+}
+
+/*
+ * region->nr_accesses is the number of sampling intervals in the last
+ * aggregation interval that access to the region has found, and region->age is
+ * the number of aggregation intervals that its access pattern has maintained.
+ * For the reason, the real meaning of the two fields depend on current
+ * sampling interval and aggregation interval.  This function updates
+ * ->nr_accesses and ->age of given damon_ctx's regions for new damon_attrs.
+ */
+static void damon_update_monitoring_results(struct damon_ctx *ctx,
+		struct damon_attrs *new_attrs)
+{
+	struct damon_attrs *old_attrs = &ctx->attrs;
+	struct damon_target *t;
+	struct damon_region *r;
+
+	/* if any interval is zero, simply forgive conversion */
+	if (!old_attrs->sample_interval || !old_attrs->aggr_interval ||
+			!new_attrs->sample_interval ||
+			!new_attrs->aggr_interval)
+		return;
+
+	damon_for_each_target(t, ctx)
+		damon_for_each_region(r, t)
+			damon_update_monitoring_result(
+					r, old_attrs, new_attrs);
+}
+
 /**
  * damon_set_attrs() - Set attributes for the monitoring.
  * @ctx:		monitoring context
@@ -443,6 +552,7 @@ int damon_set_attrs(struct damon_ctx *ctx, struct damon_attrs *attrs)
 	if (attrs->min_nr_regions > attrs->max_nr_regions)
 		return -EINVAL;
 
+	damon_update_monitoring_results(ctx, attrs);
 	ctx->attrs = *attrs;
 	return 0;
 }
@@ -1230,7 +1340,8 @@ static int kdamond_fn(void *data)
 			if (ctx->callback.after_aggregation &&
 					ctx->callback.after_aggregation(ctx))
 				break;
-			kdamond_apply_schemes(ctx);
+			if (!list_empty(&ctx->schemes))
+				kdamond_apply_schemes(ctx);
 			kdamond_reset_aggregated(ctx);
 			kdamond_split_regions(ctx);
 			if (ctx->ops.reset_aggregated)