33  * Each flow has a CoDel managed queue.
37  * For a given flow, packets are not reordered (CoDel uses a FIFO)
40  * Low memory footprint (64 bytes per flow)
117 static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow)  in dequeue_head()  argument
119 	struct sk_buff *skb = flow->head;  in dequeue_head()
121 	flow->head = skb->next;  in dequeue_head()
126 /* add skb to flow queue (tail add) */
127 static inline void flow_queue_add(struct fq_codel_flow *flow,  in flow_queue_add()  argument
130 	if (flow->head == NULL)  in flow_queue_add()
131 		flow->head = skb;  in flow_queue_add()
133 		flow->tail->next = skb;  in flow_queue_add()
134 	flow->tail = skb;  in flow_queue_add()
144 	struct fq_codel_flow *flow;  in fq_codel_drop()  local
148 	/* Queue is full! Find the fat flow and drop packet(s) from it.  in fq_codel_drop()
152 	 * In stress mode, we'll try to drop 64 packets from the flow,  in fq_codel_drop()
162 	/* Our goal is to drop half of this fat flow backlog */  in fq_codel_drop()
165 	flow = &q->flows[idx];  in fq_codel_drop()
169 		skb = dequeue_head(flow);  in fq_codel_drop()
176 	flow->cvars.count += i;  in fq_codel_drop()
190 	struct fq_codel_flow *flow;  in fq_codel_enqueue()  local
205 	flow = &q->flows[idx];  in fq_codel_enqueue()
206 	flow_queue_add(flow, skb);  in fq_codel_enqueue()
210 	if (list_empty(&flow->flowchain)) {  in fq_codel_enqueue()
211 		list_add_tail(&flow->flowchain, &q->new_flows);  in fq_codel_enqueue()
213 		flow->deficit = q->quantum;  in fq_codel_enqueue()
227 	 * in q->backlogs[] to find a fat flow.  in fq_codel_enqueue()
240 	 * If we dropped a packet for this flow, return NET_XMIT_CN,  in fq_codel_enqueue()
260 	struct fq_codel_flow *flow;  in dequeue_func()  local
263 	flow = container_of(vars, struct fq_codel_flow, cvars);  in dequeue_func()
264 	if (flow->head) {  in dequeue_func()
265 		skb = dequeue_head(flow);  in dequeue_func()
266 		q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb);  in dequeue_func()
286 	struct fq_codel_flow *flow;  in fq_codel_dequeue()  local
296 	flow = list_first_entry(head, struct fq_codel_flow, flowchain);  in fq_codel_dequeue()
298 	if (flow->deficit <= 0) {  in fq_codel_dequeue()
299 		flow->deficit += q->quantum;  in fq_codel_dequeue()
300 		list_move_tail(&flow->flowchain, &q->old_flows);  in fq_codel_dequeue()
305 			    &flow->cvars, &q->cstats, qdisc_pkt_len,  in fq_codel_dequeue()
311 			list_move_tail(&flow->flowchain, &q->old_flows);  in fq_codel_dequeue()
313 			list_del_init(&flow->flowchain);  in fq_codel_dequeue()
317 	flow->deficit -= qdisc_pkt_len(skb);  in fq_codel_dequeue()
330 static void fq_codel_flow_purge(struct fq_codel_flow *flow)  in fq_codel_flow_purge()  argument
332 	rtnl_kfree_skbs(flow->head, flow->tail);  in fq_codel_flow_purge()
333 	flow->head = NULL;  in fq_codel_flow_purge()
344 		struct fq_codel_flow *flow = q->flows + i;  in fq_codel_reset()  local
346 		fq_codel_flow_purge(flow);  in fq_codel_reset()
347 		INIT_LIST_HEAD(&flow->flowchain);  in fq_codel_reset()
348 		codel_vars_init(&flow->cvars);  in fq_codel_reset()
493 			struct fq_codel_flow *flow = q->flows + i;  in fq_codel_init()  local
495 			INIT_LIST_HEAD(&flow->flowchain);  in fq_codel_init()
496 			codel_vars_init(&flow->cvars);  in fq_codel_init()
624 		const struct fq_codel_flow *flow = &q->flows[idx];  in fq_codel_dump_class_stats()  local
629 		xstats.class_stats.deficit = flow->deficit;  in fq_codel_dump_class_stats()
631 			codel_time_to_us(flow->cvars.ldelay);  in fq_codel_dump_class_stats()
632 		xstats.class_stats.count = flow->cvars.count;  in fq_codel_dump_class_stats()
633 		xstats.class_stats.lastcount = flow->cvars.lastcount;  in fq_codel_dump_class_stats()
634 		xstats.class_stats.dropping = flow->cvars.dropping;  in fq_codel_dump_class_stats()
635 		if (flow->cvars.dropping) {  in fq_codel_dump_class_stats()
636 			codel_tdiff_t delta = flow->cvars.drop_next -  in fq_codel_dump_class_stats()
643 		if (flow->head) {  in fq_codel_dump_class_stats()
645 			skb = flow->head;  in fq_codel_dump_class_stats()