After commit 
eeb84aa0d0aff ("net_sched: sch_fq: do not assume EDT
packets are ordered"), all skbs get a non zero time_to_send
in flow_queue_add()
This means @time_next_packet variable in fq_dequeue()
can no longer be zero.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
                        fq_flow_set_throttled(q, f);
                        goto begin;
                }
-               if (time_next_packet &&
-                   (s64)(now - time_next_packet - q->ce_threshold) > 0) {
+               if ((s64)(now - time_next_packet - q->ce_threshold) > 0) {
                        INET_ECN_set_ce(skb);
                        q->stat_ce_mark++;
                }