1 files changed, 35 insertions, 0 deletions
diff --git a/examples/bpf/legacy/bpf_cyclic.c b/examples/bpf/legacy/bpf_cyclic.c
new file mode 100644
index 0000000..3359073
--- /dev/null
+++ b/examples/bpf/legacy/bpf_cyclic.c
@@ -0,0 +1,35 @@
+#include "../../../include/bpf_api.h"
+
+/* Cyclic dependency example to test the kernel's runtime upper
+ * bound on loops. Also demonstrates on how to use direct-actions,
+ * loaded as: tc filter add [...] bpf da obj [...]
+ */
+#define JMP_MAP_ID	0xabccba
+
+struct bpf_elf_map __section_maps jmp_tc = {
+	.type		= BPF_MAP_TYPE_PROG_ARRAY,
+	.id		= JMP_MAP_ID,
+	.size_key	= sizeof(uint32_t),
+	.size_value	= sizeof(uint32_t),
+	.pinning	= PIN_OBJECT_NS,
+	.max_elem	= 1,
+};
+
+__section_tail(JMP_MAP_ID, 0)
+int cls_loop(struct __sk_buff *skb)
+{
+	printt("cb: %u\n", skb->cb[0]++);
+	tail_call(skb, &jmp_tc, 0);
+
+	skb->tc_classid = TC_H_MAKE(1, 42);
+	return TC_ACT_OK;
+}
+
+__section_cls_entry
+int cls_entry(struct __sk_buff *skb)
+{
+	tail_call(skb, &jmp_tc, 0);
+	return TC_ACT_SHOT;
+}
+
+BPF_LICENSE("GPL");