summaryrefslogtreecommitdiff
path: root/include/net/gro_cells.h
blob: d15214d673b2e8e08fd6437b572278fb1359f10d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
#ifndef _NET_GRO_CELLS_H
#define _NET_GRO_CELLS_H

#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/netdevice.h>

struct gro_cell {
	struct sk_buff_head	napi_skbs;
	struct napi_struct	napi;
};

struct gro_cells {
	struct gro_cell __percpu	*cells;
};

static inline int gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb)
{
	struct gro_cell *cell;
	struct net_device *dev = skb->dev;

	if (!gcells->cells || skb_cloned(skb) || !(dev->features & NETIF_F_GRO))
		return netif_rx(skb);

	cell = this_cpu_ptr(gcells->cells);

	if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) {
		atomic_long_inc(&dev->rx_dropped);
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	__skb_queue_tail(&cell->napi_skbs, skb);
	if (skb_queue_len(&cell->napi_skbs) == 1)
		napi_schedule(&cell->napi);
	return NET_RX_SUCCESS;
}

/* called under BH context */
static inline int gro_cell_poll(struct napi_struct *napi, int budget)
{
	struct gro_cell *cell = container_of(napi, struct gro_cell, napi);
	struct sk_buff *skb;
	int work_done = 0;

	while (work_done < budget) {
		skb = __skb_dequeue(&cell->napi_skbs);
		if (!skb)
			break;
		napi_gro_receive(napi, skb);
		work_done++;
	}

	if (work_done < budget)
		napi_complete_done(napi, work_done);
	return work_done;
}

static inline int gro_cells_init(struct gro_cells *gcells, struct net_device *dev)
{
	int i;

	gcells->cells = alloc_percpu(struct gro_cell);
	if (!gcells->cells)
		return -ENOMEM;

	for_each_possible_cpu(i) {
		struct gro_cell *cell = per_cpu_ptr(gcells->cells, i);

		__skb_queue_head_init(&cell->napi_skbs);
		netif_napi_add(dev, &cell->napi, gro_cell_poll, 64);
		napi_enable(&cell->napi);
	}
	return 0;
}

static inline void gro_cells_destroy(struct gro_cells *gcells)
{
	int i;

	if (!gcells->cells)
		return;
	for_each_possible_cpu(i) {
		struct gro_cell *cell = per_cpu_ptr(gcells->cells, i);

		netif_napi_del(&cell->napi);
		__skb_queue_purge(&cell->napi_skbs);
	}
	free_percpu(gcells->cells);
	gcells->cells = NULL;
}

#endif