*             **-EPERM** if no permission to send the *sig*.
  *
  *             **-EAGAIN** if bpf program can try again.
+ *
+ * u64 bpf_jiffies64(void)
+ *     Description
+ *             Obtain the 64bit jiffies
+ *     Return
+ *             The 64 bit jiffies
  */
 #define __BPF_FUNC_MAPPER(FN)          \
        FN(unspec),                     \
        FN(probe_read_user_str),        \
        FN(probe_read_kernel_str),      \
        FN(tcp_send_ack),               \
-       FN(send_signal_thread),
+       FN(send_signal_thread),         \
+       FN(jiffies64),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call