1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (c) 2016 Qualcomm Atheros, Inc 4 * 5 * Based on net/sched/sch_fq_codel.c 6 */ 7 #ifndef __NET_SCHED_FQ_H 8 #define __NET_SCHED_FQ_H 9 10 struct fq_tin; 11 12 /** 13 * struct fq_flow - per traffic flow queue 14 * 15 * @tin: owner of this flow. Used to manage collisions, i.e. when a packet 16 * hashes to an index which points to a flow that is already owned by a 17 * different tin the packet is destined to. In such case the implementer 18 * must provide a fallback flow 19 * @flowchain: can be linked to fq_tin's new_flows or old_flows. Used for DRR++ 20 * (deficit round robin) based round robin queuing similar to the one 21 * found in net/sched/sch_fq_codel.c 22 * @backlogchain: can be linked to other fq_flow and fq. Used to keep track of 23 * fat flows and efficient head-dropping if packet limit is reached 24 * @queue: sk_buff queue to hold packets 25 * @backlog: number of bytes pending in the queue. The number of packets can be 26 * found in @queue.qlen 27 * @deficit: used for DRR++ 28 */ 29 struct fq_flow { 30 struct fq_tin *tin; 31 struct list_head flowchain; 32 struct list_head backlogchain; 33 struct sk_buff_head queue; 34 u32 backlog; 35 int deficit; 36 }; 37 38 /** 39 * struct fq_tin - a logical container of fq_flows 40 * 41 * Used to group fq_flows into a logical aggregate. DRR++ scheme is used to 42 * pull interleaved packets out of the associated flows. 43 * 44 * @new_flows: linked list of fq_flow 45 * @old_flows: linked list of fq_flow 46 */ 47 struct fq_tin { 48 struct list_head new_flows; 49 struct list_head old_flows; 50 u32 backlog_bytes; 51 u32 backlog_packets; 52 u32 overlimit; 53 u32 collisions; 54 u32 flows; 55 u32 tx_bytes; 56 u32 tx_packets; 57 }; 58 59 /** 60 * struct fq - main container for fair queuing purposes 61 * 62 * @backlogs: linked to fq_flows. Used to maintain fat flows for efficient 63 * head-dropping when @backlog reaches @limit 64 * @limit: max number of packets that can be queued across all flows 65 * @backlog: number of packets queued across all flows 66 */ 67 struct fq { 68 struct fq_flow *flows; 69 struct list_head backlogs; 70 spinlock_t lock; 71 u32 flows_cnt; 72 siphash_key_t perturbation; 73 u32 limit; 74 u32 memory_limit; 75 u32 memory_usage; 76 u32 quantum; 77 u32 backlog; 78 u32 overlimit; 79 u32 overmemory; 80 u32 collisions; 81 }; 82 83 typedef struct sk_buff *fq_tin_dequeue_t(struct fq *, 84 struct fq_tin *, 85 struct fq_flow *flow); 86 87 typedef void fq_skb_free_t(struct fq *, 88 struct fq_tin *, 89 struct fq_flow *, 90 struct sk_buff *); 91 92 /* Return %true to filter (drop) the frame. */ 93 typedef bool fq_skb_filter_t(struct fq *, 94 struct fq_tin *, 95 struct fq_flow *, 96 struct sk_buff *, 97 void *); 98 99 typedef struct fq_flow *fq_flow_get_default_t(struct fq *, 100 struct fq_tin *, 101 int idx, 102 struct sk_buff *); 103 104 #endif 105