1 files changed, 51 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/include/lru_gen_util.h b/tools/testing/selftests/kvm/include/lru_gen_util.h
new file mode 100644
index 000000000000..d32ff5d8ffd0
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/lru_gen_util.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Tools for integrating with lru_gen, like parsing the lru_gen debugfs output.
+ *
+ * Copyright (C) 2025, Google LLC.
+ */
+#ifndef SELFTEST_KVM_LRU_GEN_UTIL_H
+#define SELFTEST_KVM_LRU_GEN_UTIL_H
+
+#include <inttypes.h>
+#include <limits.h>
+#include <stdlib.h>
+
+#include "test_util.h"
+
+#define MAX_NR_GENS 16 /* MAX_NR_GENS in include/linux/mmzone.h */
+#define MAX_NR_NODES 4 /* Maximum number of nodes supported by the test */
+
+#define LRU_GEN_DEBUGFS "/sys/kernel/debug/lru_gen"
+#define LRU_GEN_ENABLED_PATH "/sys/kernel/mm/lru_gen/enabled"
+#define LRU_GEN_ENABLED 1
+#define LRU_GEN_MM_WALK 2
+
+struct generation_stats {
+	int gen;
+	long age_ms;
+	long nr_anon;
+	long nr_file;
+};
+
+struct node_stats {
+	int node;
+	int nr_gens; /* Number of populated gens entries. */
+	struct generation_stats gens[MAX_NR_GENS];
+};
+
+struct memcg_stats {
+	unsigned long memcg_id;
+	int nr_nodes; /* Number of populated nodes entries. */
+	struct node_stats nodes[MAX_NR_NODES];
+};
+
+void lru_gen_read_memcg_stats(struct memcg_stats *stats, const char *memcg);
+long lru_gen_sum_memcg_stats(const struct memcg_stats *stats);
+long lru_gen_sum_memcg_stats_for_gen(int gen, const struct memcg_stats *stats);
+void lru_gen_do_aging(struct memcg_stats *stats, const char *memcg);
+int lru_gen_find_generation(const struct memcg_stats *stats,
+			    unsigned long total_pages);
+bool lru_gen_usable(void);
+
+#endif /* SELFTEST_KVM_LRU_GEN_UTIL_H */