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kernel/linux-imx6_3.14.28/include/net/gro_cells.h 2.41 KB
6b13f685e   김민수   BSP 최초 추가
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  #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;
  } ____cacheline_aligned_in_smp;
  
  struct gro_cells {
  	unsigned int		gro_cells_mask;
  	struct gro_cell		*cells;
  };
  
  static inline void gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb)
  {
  	struct gro_cell *cell = gcells->cells;
  	struct net_device *dev = skb->dev;
  
  	if (!cell || skb_cloned(skb) || !(dev->features & NETIF_F_GRO)) {
  		netif_rx(skb);
  		return;
  	}
  
  	if (skb_rx_queue_recorded(skb))
  		cell += skb_get_rx_queue(skb) & gcells->gro_cells_mask;
  
  	if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) {
  		atomic_long_inc(&dev->rx_dropped);
  		kfree_skb(skb);
  		return;
  	}
  
  	/* We run in BH context */
  	spin_lock(&cell->napi_skbs.lock);
  
  	__skb_queue_tail(&cell->napi_skbs, skb);
  	if (skb_queue_len(&cell->napi_skbs) == 1)
  		napi_schedule(&cell->napi);
  
  	spin_unlock(&cell->napi_skbs.lock);
  }
  
  /* called unser 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;
  
  	spin_lock(&cell->napi_skbs.lock);
  	while (work_done < budget) {
  		skb = __skb_dequeue(&cell->napi_skbs);
  		if (!skb)
  			break;
  		spin_unlock(&cell->napi_skbs.lock);
  		napi_gro_receive(napi, skb);
  		work_done++;
  		spin_lock(&cell->napi_skbs.lock);
  	}
  
  	if (work_done < budget)
  		napi_complete(napi);
  	spin_unlock(&cell->napi_skbs.lock);
  	return work_done;
  }
  
  static inline int gro_cells_init(struct gro_cells *gcells, struct net_device *dev)
  {
  	int i;
  
  	gcells->gro_cells_mask = roundup_pow_of_two(netif_get_num_default_rss_queues()) - 1;
  	gcells->cells = kcalloc(gcells->gro_cells_mask + 1,
  				sizeof(struct gro_cell),
  				GFP_KERNEL);
  	if (!gcells->cells)
  		return -ENOMEM;
  
  	for (i = 0; i <= gcells->gro_cells_mask; i++) {
  		struct gro_cell *cell = 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)
  {
  	struct gro_cell *cell = gcells->cells;
  	int i;
  
  	if (!cell)
  		return;
  	for (i = 0; i <= gcells->gro_cells_mask; i++,cell++) {
  		netif_napi_del(&cell->napi);
  		skb_queue_purge(&cell->napi_skbs);
  	}
  	kfree(gcells->cells);
  	gcells->cells = NULL;
  }
  
  #endif