1 files changed, 71 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/free_timer.c b/tools/testing/selftests/bpf/progs/free_timer.c
new file mode 100644
index 000000000000..4501ae8fc414
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/free_timer.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2025. Huawei Technologies Co., Ltd */
+#include <linux/bpf.h>
+#include <time.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+
+#define MAX_ENTRIES 8
+
+struct map_value {
+	struct bpf_timer timer;
+};
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__type(key, int);
+	__type(value, struct map_value);
+	__uint(max_entries, MAX_ENTRIES);
+} map SEC(".maps");
+
+static int timer_cb(void *map, void *key, struct map_value *value)
+{
+	volatile int sum = 0;
+	int i;
+
+	bpf_for(i, 0, 1024 * 1024) sum += i;
+
+	return 0;
+}
+
+static int start_cb(int key)
+{
+	struct map_value *value;
+
+	value = bpf_map_lookup_elem(&map, (void *)&key);
+	if (!value)
+		return 0;
+
+	bpf_timer_init(&value->timer, &map, CLOCK_MONOTONIC);
+	bpf_timer_set_callback(&value->timer, timer_cb);
+	/* Hope 100us will be enough to wake-up and run the overwrite thread */
+	bpf_timer_start(&value->timer, 100000, BPF_F_TIMER_CPU_PIN);
+
+	return 0;
+}
+
+static int overwrite_cb(int key)
+{
+	struct map_value zero = {};
+
+	/* Free the timer which may run on other CPU */
+	bpf_map_update_elem(&map, (void *)&key, &zero, BPF_ANY);
+
+	return 0;
+}
+
+SEC("syscall")
+int BPF_PROG(start_timer)
+{
+	bpf_loop(MAX_ENTRIES, start_cb, NULL, 0);
+	return 0;
+}
+
+SEC("syscall")
+int BPF_PROG(overwrite_timer)
+{
+	bpf_loop(MAX_ENTRIES, overwrite_cb, NULL, 0);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";