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 } ____cacheline_aligned_in_smp;
12
13 struct gro_cells {
14 unsigned int gro_cells_mask;
15 struct gro_cell *cells;
16 };
17
gro_cells_receive(struct gro_cells * gcells,struct sk_buff * skb)18 static inline void gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb)
19 {
20 struct gro_cell *cell = gcells->cells;
21 struct net_device *dev = skb->dev;
22
23 if (!cell || skb_cloned(skb) || !(dev->features & NETIF_F_GRO)) {
24 netif_rx(skb);
25 return;
26 }
27
28 if (skb_rx_queue_recorded(skb))
29 cell += skb_get_rx_queue(skb) & gcells->gro_cells_mask;
30
31 if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) {
32 atomic_long_inc(&dev->rx_dropped);
33 kfree_skb(skb);
34 return;
35 }
36
37 /* We run in BH context */
38 spin_lock(&cell->napi_skbs.lock);
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 spin_unlock(&cell->napi_skbs.lock);
45 }
46
47 /* called unser BH context */
gro_cell_poll(struct napi_struct * napi,int budget)48 static inline int gro_cell_poll(struct napi_struct *napi, int budget)
49 {
50 struct gro_cell *cell = container_of(napi, struct gro_cell, napi);
51 struct sk_buff *skb;
52 int work_done = 0;
53
54 spin_lock(&cell->napi_skbs.lock);
55 while (work_done < budget) {
56 skb = __skb_dequeue(&cell->napi_skbs);
57 if (!skb)
58 break;
59 spin_unlock(&cell->napi_skbs.lock);
60 napi_gro_receive(napi, skb);
61 work_done++;
62 spin_lock(&cell->napi_skbs.lock);
63 }
64
65 if (work_done < budget)
66 napi_complete(napi);
67 spin_unlock(&cell->napi_skbs.lock);
68 return work_done;
69 }
70
gro_cells_init(struct gro_cells * gcells,struct net_device * dev)71 static inline int gro_cells_init(struct gro_cells *gcells, struct net_device *dev)
72 {
73 int i;
74
75 gcells->gro_cells_mask = roundup_pow_of_two(netif_get_num_default_rss_queues()) - 1;
76 gcells->cells = kcalloc(gcells->gro_cells_mask + 1,
77 sizeof(struct gro_cell),
78 GFP_KERNEL);
79 if (!gcells->cells)
80 return -ENOMEM;
81
82 for (i = 0; i <= gcells->gro_cells_mask; i++) {
83 struct gro_cell *cell = gcells->cells + i;
84
85 skb_queue_head_init(&cell->napi_skbs);
86 netif_napi_add(dev, &cell->napi, gro_cell_poll, 64);
87 napi_enable(&cell->napi);
88 }
89 return 0;
90 }
91
gro_cells_destroy(struct gro_cells * gcells)92 static inline void gro_cells_destroy(struct gro_cells *gcells)
93 {
94 struct gro_cell *cell = gcells->cells;
95 int i;
96
97 if (!cell)
98 return;
99 for (i = 0; i <= gcells->gro_cells_mask; i++,cell++) {
100 netif_napi_del(&cell->napi);
101 skb_queue_purge(&cell->napi_skbs);
102 }
103 kfree(gcells->cells);
104 gcells->cells = NULL;
105 }
106
107 #endif
108