v4.19.13 snapshot.
diff --git a/include/net/fq_impl.h b/include/net/fq_impl.h
new file mode 100644
index 0000000..be7c0fa
--- /dev/null
+++ b/include/net/fq_impl.h
@@ -0,0 +1,337 @@
+/*
+ * Copyright (c) 2016 Qualcomm Atheros, Inc
+ *
+ * GPL v2
+ *
+ * Based on net/sched/sch_fq_codel.c
+ */
+#ifndef __NET_SCHED_FQ_IMPL_H
+#define __NET_SCHED_FQ_IMPL_H
+
+#include <net/fq.h>
+
+/* functions that are embedded into includer */
+
+static void fq_adjust_removal(struct fq *fq,
+ struct fq_flow *flow,
+ struct sk_buff *skb)
+{
+ struct fq_tin *tin = flow->tin;
+
+ tin->backlog_bytes -= skb->len;
+ tin->backlog_packets--;
+ flow->backlog -= skb->len;
+ fq->backlog--;
+ fq->memory_usage -= skb->truesize;
+}
+
+static void fq_rejigger_backlog(struct fq *fq, struct fq_flow *flow)
+{
+ struct fq_flow *i;
+
+ if (flow->backlog == 0) {
+ list_del_init(&flow->backlogchain);
+ } else {
+ i = flow;
+
+ list_for_each_entry_continue(i, &fq->backlogs, backlogchain)
+ if (i->backlog < flow->backlog)
+ break;
+
+ list_move_tail(&flow->backlogchain,
+ &i->backlogchain);
+ }
+}
+
+static struct sk_buff *fq_flow_dequeue(struct fq *fq,
+ struct fq_flow *flow)
+{
+ struct sk_buff *skb;
+
+ lockdep_assert_held(&fq->lock);
+
+ skb = __skb_dequeue(&flow->queue);
+ if (!skb)
+ return NULL;
+
+ fq_adjust_removal(fq, flow, skb);
+ fq_rejigger_backlog(fq, flow);
+
+ return skb;
+}
+
+static struct sk_buff *fq_tin_dequeue(struct fq *fq,
+ struct fq_tin *tin,
+ fq_tin_dequeue_t dequeue_func)
+{
+ struct fq_flow *flow;
+ struct list_head *head;
+ struct sk_buff *skb;
+
+ lockdep_assert_held(&fq->lock);
+
+begin:
+ head = &tin->new_flows;
+ if (list_empty(head)) {
+ head = &tin->old_flows;
+ if (list_empty(head))
+ return NULL;
+ }
+
+ flow = list_first_entry(head, struct fq_flow, flowchain);
+
+ if (flow->deficit <= 0) {
+ flow->deficit += fq->quantum;
+ list_move_tail(&flow->flowchain,
+ &tin->old_flows);
+ goto begin;
+ }
+
+ skb = dequeue_func(fq, tin, flow);
+ if (!skb) {
+ /* force a pass through old_flows to prevent starvation */
+ if ((head == &tin->new_flows) &&
+ !list_empty(&tin->old_flows)) {
+ list_move_tail(&flow->flowchain, &tin->old_flows);
+ } else {
+ list_del_init(&flow->flowchain);
+ flow->tin = NULL;
+ }
+ goto begin;
+ }
+
+ flow->deficit -= skb->len;
+ tin->tx_bytes += skb->len;
+ tin->tx_packets++;
+
+ return skb;
+}
+
+static struct fq_flow *fq_flow_classify(struct fq *fq,
+ struct fq_tin *tin,
+ struct sk_buff *skb,
+ fq_flow_get_default_t get_default_func)
+{
+ struct fq_flow *flow;
+ u32 hash;
+ u32 idx;
+
+ lockdep_assert_held(&fq->lock);
+
+ hash = skb_get_hash_perturb(skb, fq->perturbation);
+ idx = reciprocal_scale(hash, fq->flows_cnt);
+ flow = &fq->flows[idx];
+
+ if (flow->tin && flow->tin != tin) {
+ flow = get_default_func(fq, tin, idx, skb);
+ tin->collisions++;
+ fq->collisions++;
+ }
+
+ if (!flow->tin)
+ tin->flows++;
+
+ return flow;
+}
+
+static void fq_recalc_backlog(struct fq *fq,
+ struct fq_tin *tin,
+ struct fq_flow *flow)
+{
+ struct fq_flow *i;
+
+ if (list_empty(&flow->backlogchain))
+ list_add_tail(&flow->backlogchain, &fq->backlogs);
+
+ i = flow;
+ list_for_each_entry_continue_reverse(i, &fq->backlogs,
+ backlogchain)
+ if (i->backlog > flow->backlog)
+ break;
+
+ list_move(&flow->backlogchain, &i->backlogchain);
+}
+
+static void fq_tin_enqueue(struct fq *fq,
+ struct fq_tin *tin,
+ struct sk_buff *skb,
+ fq_skb_free_t free_func,
+ fq_flow_get_default_t get_default_func)
+{
+ struct fq_flow *flow;
+ bool oom;
+
+ lockdep_assert_held(&fq->lock);
+
+ flow = fq_flow_classify(fq, tin, skb, get_default_func);
+
+ flow->tin = tin;
+ flow->backlog += skb->len;
+ tin->backlog_bytes += skb->len;
+ tin->backlog_packets++;
+ fq->memory_usage += skb->truesize;
+ fq->backlog++;
+
+ fq_recalc_backlog(fq, tin, flow);
+
+ if (list_empty(&flow->flowchain)) {
+ flow->deficit = fq->quantum;
+ list_add_tail(&flow->flowchain,
+ &tin->new_flows);
+ }
+
+ __skb_queue_tail(&flow->queue, skb);
+ oom = (fq->memory_usage > fq->memory_limit);
+ while (fq->backlog > fq->limit || oom) {
+ flow = list_first_entry_or_null(&fq->backlogs,
+ struct fq_flow,
+ backlogchain);
+ if (!flow)
+ return;
+
+ skb = fq_flow_dequeue(fq, flow);
+ if (!skb)
+ return;
+
+ free_func(fq, flow->tin, flow, skb);
+
+ flow->tin->overlimit++;
+ fq->overlimit++;
+ if (oom) {
+ fq->overmemory++;
+ oom = (fq->memory_usage > fq->memory_limit);
+ }
+ }
+}
+
+static void fq_flow_filter(struct fq *fq,
+ struct fq_flow *flow,
+ fq_skb_filter_t filter_func,
+ void *filter_data,
+ fq_skb_free_t free_func)
+{
+ struct fq_tin *tin = flow->tin;
+ struct sk_buff *skb, *tmp;
+
+ lockdep_assert_held(&fq->lock);
+
+ skb_queue_walk_safe(&flow->queue, skb, tmp) {
+ if (!filter_func(fq, tin, flow, skb, filter_data))
+ continue;
+
+ __skb_unlink(skb, &flow->queue);
+ fq_adjust_removal(fq, flow, skb);
+ free_func(fq, tin, flow, skb);
+ }
+
+ fq_rejigger_backlog(fq, flow);
+}
+
+static void fq_tin_filter(struct fq *fq,
+ struct fq_tin *tin,
+ fq_skb_filter_t filter_func,
+ void *filter_data,
+ fq_skb_free_t free_func)
+{
+ struct fq_flow *flow;
+
+ lockdep_assert_held(&fq->lock);
+
+ list_for_each_entry(flow, &tin->new_flows, flowchain)
+ fq_flow_filter(fq, flow, filter_func, filter_data, free_func);
+ list_for_each_entry(flow, &tin->old_flows, flowchain)
+ fq_flow_filter(fq, flow, filter_func, filter_data, free_func);
+}
+
+static void fq_flow_reset(struct fq *fq,
+ struct fq_flow *flow,
+ fq_skb_free_t free_func)
+{
+ struct sk_buff *skb;
+
+ while ((skb = fq_flow_dequeue(fq, flow)))
+ free_func(fq, flow->tin, flow, skb);
+
+ if (!list_empty(&flow->flowchain))
+ list_del_init(&flow->flowchain);
+
+ if (!list_empty(&flow->backlogchain))
+ list_del_init(&flow->backlogchain);
+
+ flow->tin = NULL;
+
+ WARN_ON_ONCE(flow->backlog);
+}
+
+static void fq_tin_reset(struct fq *fq,
+ struct fq_tin *tin,
+ fq_skb_free_t free_func)
+{
+ struct list_head *head;
+ struct fq_flow *flow;
+
+ for (;;) {
+ head = &tin->new_flows;
+ if (list_empty(head)) {
+ head = &tin->old_flows;
+ if (list_empty(head))
+ break;
+ }
+
+ flow = list_first_entry(head, struct fq_flow, flowchain);
+ fq_flow_reset(fq, flow, free_func);
+ }
+
+ WARN_ON_ONCE(tin->backlog_bytes);
+ WARN_ON_ONCE(tin->backlog_packets);
+}
+
+static void fq_flow_init(struct fq_flow *flow)
+{
+ INIT_LIST_HEAD(&flow->flowchain);
+ INIT_LIST_HEAD(&flow->backlogchain);
+ __skb_queue_head_init(&flow->queue);
+}
+
+static void fq_tin_init(struct fq_tin *tin)
+{
+ INIT_LIST_HEAD(&tin->new_flows);
+ INIT_LIST_HEAD(&tin->old_flows);
+}
+
+static int fq_init(struct fq *fq, int flows_cnt)
+{
+ int i;
+
+ memset(fq, 0, sizeof(fq[0]));
+ INIT_LIST_HEAD(&fq->backlogs);
+ spin_lock_init(&fq->lock);
+ fq->flows_cnt = max_t(u32, flows_cnt, 1);
+ fq->perturbation = prandom_u32();
+ fq->quantum = 300;
+ fq->limit = 8192;
+ fq->memory_limit = 16 << 20; /* 16 MBytes */
+
+ fq->flows = kcalloc(fq->flows_cnt, sizeof(fq->flows[0]), GFP_KERNEL);
+ if (!fq->flows)
+ return -ENOMEM;
+
+ for (i = 0; i < fq->flows_cnt; i++)
+ fq_flow_init(&fq->flows[i]);
+
+ return 0;
+}
+
+static void fq_reset(struct fq *fq,
+ fq_skb_free_t free_func)
+{
+ int i;
+
+ for (i = 0; i < fq->flows_cnt; i++)
+ fq_flow_reset(fq, &fq->flows[i], free_func);
+
+ kfree(fq->flows);
+ fq->flows = NULL;
+}
+
+#endif