bpf_jit_emit_exit_insn
int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx, int tmp_reg, long exit_addr);
ret = bpf_jit_emit_exit_insn(image, ctx, _R0, exit_addr);
ret = bpf_jit_emit_exit_insn(image, ctx, tmp1_reg, exit_addr);