Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 90caf67b authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net_sched: sch_fq: remove dead code dealing with retransmits 



With the earliest departure time model, we no longer plan
special casing TCP retransmits. We therefore remove dead
code (since most compilers understood skb_is_retransmit()
was false)

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c092dd5f

net/sched/sch_fq.c

+5 −53
Original line number Diff line number Diff line
@@ -106,7 +106,6 @@ struct fq_sched_data { 


	u64		stat_gc_flows;

	u64		stat_internal_packets;

	u64		stat_tcp_retrans;

	u64		stat_throttled;

	u64		stat_flows_plimit;

	u64		stat_pkts_too_long;
@@ -327,62 +326,17 @@ static struct sk_buff *fq_dequeue_head(struct Qdisc *sch, struct fq_flow *flow) 
	return skb;

}



/* We might add in the future detection of retransmits

 * For the time being, just return false

 */

static bool skb_is_retransmit(struct sk_buff *skb)

{

	return false;

}



/* add skb to flow queue

 * flow queue is a linked list, kind of FIFO, except for TCP retransmits

 * We special case tcp retransmits to be transmitted before other packets.

 * We rely on fact that TCP retransmits are unlikely, so we do not waste

 * a separate queue or a pointer.

 * head->  [retrans pkt 1]

 *         [retrans pkt 2]

 *         [ normal pkt 1]

 *         [ normal pkt 2]

 *         [ normal pkt 3]

 * tail->  [ normal pkt 4]

 */

static void flow_queue_add(struct fq_flow *flow, struct sk_buff *skb)

{

	struct sk_buff *prev, *head = flow->head;

	struct sk_buff *head = flow->head;



	skb->next = NULL;

	if (!head) {

	if (!head)

		flow->head = skb;

		flow->tail = skb;

		return;

	}

	if (likely(!skb_is_retransmit(skb))) {

	else

		flow->tail->next = skb;

		flow->tail = skb;

		return;

	}



	/* This skb is a tcp retransmit,

	 * find the last retrans packet in the queue

	 */

	prev = NULL;

	while (skb_is_retransmit(head)) {

		prev = head;

		head = head->next;

		if (!head)

			break;

	}

	if (!prev) { /* no rtx packet in queue, become the new head */

		skb->next = flow->head;

		flow->head = skb;

	} else {

		if (prev == flow->tail)

	flow->tail = skb;

		else

			skb->next = prev->next;

		prev->next = skb;

	}

}



static int fq_enqueue(struct sk_buff *skb, struct Qdisc *sch,
@@ -401,8 +355,6 @@ static int fq_enqueue(struct sk_buff *skb, struct Qdisc *sch, 
	}



	f->qlen++;

	if (skb_is_retransmit(skb))

		q->stat_tcp_retrans++;

	qdisc_qstats_backlog_inc(sch, skb);

	if (fq_flow_is_detached(f)) {

		struct sock *sk = skb->sk;
@@ -874,7 +826,7 @@ static int fq_dump_stats(struct Qdisc *sch, struct gnet_dump *d) 


	st.gc_flows		  = q->stat_gc_flows;

	st.highprio_packets	  = q->stat_internal_packets;

	st.tcp_retrans		  = q->stat_tcp_retrans;

	st.tcp_retrans		  = 0;

	st.throttled		  = q->stat_throttled;

	st.flows_plimit		  = q->stat_flows_plimit;

	st.pkts_too_long	  = q->stat_pkts_too_long;