1 #ifndef _NET_GRO_CELLS_H
2 #define _NET_GRO_CELLS_H
3
4 #include <linux/skbuff.h>
5 #include <linux/slab.h>
6 #include <linux/netdevice.h>
7
8 struct gro_cell {
9 struct sk_buff_head napi_skbs;
10 struct napi_struct napi;
11 };
12
13 struct gro_cells {
14 struct gro_cell __percpu *cells;
15 };
16
gro_cells_receive(struct gro_cells * gcells,struct sk_buff * skb)17 static inline void gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb)
18 {
19 struct gro_cell *cell;
20 struct net_device *dev = skb->dev;
21
22 rcu_read_lock();
23 if (unlikely(!(dev->flags & IFF_UP)))
24 goto drop;
25
26 if (!gcells->cells || skb_cloned(skb) || !(dev->features & NETIF_F_GRO)) {
27 netif_rx(skb);
28 goto unlock;
29 }
30
31 cell = this_cpu_ptr(gcells->cells);
32
33 if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) {
34 drop:
35 atomic_long_inc(&dev->rx_dropped);
36 kfree_skb(skb);
37 goto unlock;
38 }
39
40 __skb_queue_tail(&cell->napi_skbs, skb);
41 if (skb_queue_len(&cell->napi_skbs) == 1)
42 napi_schedule(&cell->napi);
43
44 unlock:
45 rcu_read_unlock();
46 }
47
48 /* called under BH context */
gro_cell_poll(struct napi_struct * napi,int budget)49 static inline int gro_cell_poll(struct napi_struct *napi, int budget)
50 {
51 struct gro_cell *cell = container_of(napi, struct gro_cell, napi);
52 struct sk_buff *skb;
53 int work_done = 0;
54
55 while (work_done < budget) {
56 skb = __skb_dequeue(&cell->napi_skbs);
57 if (!skb)
58 break;
59 napi_gro_receive(napi, skb);
60 work_done++;
61 }
62
63 if (work_done < budget)
64 napi_complete_done(napi, work_done);
65 return work_done;
66 }
67
gro_cells_init(struct gro_cells * gcells,struct net_device * dev)68 static inline int gro_cells_init(struct gro_cells *gcells, struct net_device *dev)
69 {
70 int i;
71
72 gcells->cells = alloc_percpu(struct gro_cell);
73 if (!gcells->cells)
74 return -ENOMEM;
75
76 for_each_possible_cpu(i) {
77 struct gro_cell *cell = per_cpu_ptr(gcells->cells, i);
78
79 __skb_queue_head_init(&cell->napi_skbs);
80 netif_napi_add(dev, &cell->napi, gro_cell_poll, 64);
81 napi_enable(&cell->napi);
82 }
83 return 0;
84 }
85
gro_cells_destroy(struct gro_cells * gcells)86 static inline void gro_cells_destroy(struct gro_cells *gcells)
87 {
88 int i;
89
90 if (!gcells->cells)
91 return;
92 for_each_possible_cpu(i) {
93 struct gro_cell *cell = per_cpu_ptr(gcells->cells, i);
94
95 napi_disable(&cell->napi);
96 netif_napi_del(&cell->napi);
97 __skb_queue_purge(&cell->napi_skbs);
98 }
99 free_percpu(gcells->cells);
100 gcells->cells = NULL;
101 }
102
103 #endif
104