| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * Copyright (c) 2016 Qualcomm Atheros, Inc |
| * |
| * 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, unsigned int packets, |
| unsigned int bytes, unsigned int truesize) |
| { |
| struct fq_tin *tin = flow->tin; |
| int idx; |
| |
| tin->backlog_bytes -= bytes; |
| tin->backlog_packets -= packets; |
| flow->backlog -= bytes; |
| fq->backlog -= packets; |
| fq->memory_usage -= truesize; |
| |
| if (flow->backlog) |
| return; |
| |
| if (flow == &tin->default_flow) { |
| list_del_init(&tin->tin_list); |
| return; |
| } |
| |
| idx = flow - fq->flows; |
| __clear_bit(idx, fq->flows_bitmap); |
| } |
| |
| static void fq_adjust_removal(struct fq *fq, |
| struct fq_flow *flow, |
| struct sk_buff *skb) |
| { |
| __fq_adjust_removal(fq, flow, 1, skb->len, skb->truesize); |
| } |
| |
| 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); |
| |
| return skb; |
| } |
| |
| static int fq_flow_drop(struct fq *fq, struct fq_flow *flow, |
| fq_skb_free_t free_func) |
| { |
| unsigned int packets = 0, bytes = 0, truesize = 0; |
| struct fq_tin *tin = flow->tin; |
| struct sk_buff *skb; |
| int pending; |
| |
| lockdep_assert_held(&fq->lock); |
| |
| pending = min_t(int, 32, skb_queue_len(&flow->queue) / 2); |
| do { |
| skb = __skb_dequeue(&flow->queue); |
| if (!skb) |
| break; |
| |
| packets++; |
| bytes += skb->len; |
| truesize += skb->truesize; |
| free_func(fq, tin, flow, skb); |
| } while (packets < pending); |
| |
| __fq_adjust_removal(fq, flow, packets, bytes, truesize); |
| |
| return packets; |
| } |
| |
| 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 u32 fq_flow_idx(struct fq *fq, struct sk_buff *skb) |
| { |
| u32 hash = skb_get_hash(skb); |
| |
| return reciprocal_scale(hash, fq->flows_cnt); |
| } |
| |
| static struct fq_flow *fq_flow_classify(struct fq *fq, |
| struct fq_tin *tin, u32 idx, |
| struct sk_buff *skb) |
| { |
| struct fq_flow *flow; |
| |
| lockdep_assert_held(&fq->lock); |
| |
| flow = &fq->flows[idx]; |
| if (flow->tin && flow->tin != tin) { |
| flow = &tin->default_flow; |
| tin->collisions++; |
| fq->collisions++; |
| } |
| |
| if (!flow->tin) |
| tin->flows++; |
| |
| return flow; |
| } |
| |
| static struct fq_flow *fq_find_fattest_flow(struct fq *fq) |
| { |
| struct fq_tin *tin; |
| struct fq_flow *flow = NULL; |
| u32 len = 0; |
| int i; |
| |
| for_each_set_bit(i, fq->flows_bitmap, fq->flows_cnt) { |
| struct fq_flow *cur = &fq->flows[i]; |
| unsigned int cur_len; |
| |
| cur_len = cur->backlog; |
| if (cur_len <= len) |
| continue; |
| |
| flow = cur; |
| len = cur_len; |
| } |
| |
| list_for_each_entry(tin, &fq->tin_backlog, tin_list) { |
| unsigned int cur_len = tin->default_flow.backlog; |
| |
| if (cur_len <= len) |
| continue; |
| |
| flow = &tin->default_flow; |
| len = cur_len; |
| } |
| |
| return flow; |
| } |
| |
| static void fq_tin_enqueue(struct fq *fq, |
| struct fq_tin *tin, u32 idx, |
| struct sk_buff *skb, |
| fq_skb_free_t free_func) |
| { |
| struct fq_flow *flow; |
| bool oom; |
| |
| lockdep_assert_held(&fq->lock); |
| |
| flow = fq_flow_classify(fq, tin, idx, skb); |
| |
| if (!flow->backlog) { |
| if (flow != &tin->default_flow) |
| __set_bit(idx, fq->flows_bitmap); |
| else if (list_empty(&tin->tin_list)) |
| list_add(&tin->tin_list, &fq->tin_backlog); |
| } |
| |
| flow->tin = tin; |
| flow->backlog += skb->len; |
| tin->backlog_bytes += skb->len; |
| tin->backlog_packets++; |
| fq->memory_usage += skb->truesize; |
| fq->backlog++; |
| |
| 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 = fq_find_fattest_flow(fq); |
| if (!flow) |
| return; |
| |
| if (!fq_flow_drop(fq, flow, free_func)) |
| return; |
| |
| 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); |
| } |
| } |
| |
| 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 fq_tin *tin = flow->tin; |
| struct sk_buff *skb; |
| |
| while ((skb = fq_flow_dequeue(fq, flow))) |
| free_func(fq, tin, flow, skb); |
| |
| if (!list_empty(&flow->flowchain)) { |
| list_del_init(&flow->flowchain); |
| if (list_empty(&tin->new_flows) && |
| list_empty(&tin->old_flows)) |
| list_del_init(&tin->tin_list); |
| } |
| |
| 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(!list_empty(&tin->tin_list)); |
| 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); |
| __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); |
| INIT_LIST_HEAD(&tin->tin_list); |
| fq_flow_init(&tin->default_flow); |
| } |
| |
| static int fq_init(struct fq *fq, int flows_cnt) |
| { |
| int i; |
| |
| memset(fq, 0, sizeof(fq[0])); |
| spin_lock_init(&fq->lock); |
| INIT_LIST_HEAD(&fq->tin_backlog); |
| fq->flows_cnt = max_t(u32, flows_cnt, 1); |
| fq->quantum = 300; |
| fq->limit = 8192; |
| fq->memory_limit = 16 << 20; /* 16 MBytes */ |
| |
| fq->flows = kvcalloc(fq->flows_cnt, sizeof(fq->flows[0]), GFP_KERNEL); |
| if (!fq->flows) |
| return -ENOMEM; |
| |
| fq->flows_bitmap = bitmap_zalloc(fq->flows_cnt, GFP_KERNEL); |
| if (!fq->flows_bitmap) { |
| kvfree(fq->flows); |
| fq->flows = NULL; |
| 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); |
| |
| kvfree(fq->flows); |
| fq->flows = NULL; |
| |
| bitmap_free(fq->flows_bitmap); |
| fq->flows_bitmap = NULL; |
| } |
| |
| #endif |