On Tue, 2013-08-13 at 15:28 +0800, Hayes Wang wrote:
> +
> +static void rx_bottom(struct r8152 *tp)
> +{
> + struct net_device_stats *stats;
> + struct net_device *netdev;
> + struct rx_agg *agg;
> + struct rx_desc *rx_desc;
> + unsigned long lockflags;
> + struct list_head *cursor, *next;
> + struct sk_buff *skb;
> + struct urb *urb;
> + unsigned pkt_len;
> + int len_used;
> + u8 *rx_data;
> + int ret;
> +
> + netdev = tp->netdev;
> +
> + if (!netif_running(netdev))
> return;
> - dev_kfree_skb_irq(tp->tx_skb);
> - if (!netif_device_present(tp->netdev))
> +
> + stats = rtl8152_get_stats(netdev);
> +
> + spin_lock_irqsave(&tp->rx_lock, lockflags);
> + list_for_each_safe(cursor, next, &tp->rx_done) {
> + list_del_init(cursor);
> + spin_unlock_irqrestore(&tp->rx_lock, lockflags);
> +
> + agg = list_entry(cursor, struct rx_agg, list);
> + urb = agg->urb;
> + if (urb->actual_length < ETH_ZLEN) {
> + ret = r8152_submit_rx(tp, agg, GFP_ATOMIC);
> + spin_lock_irqsave(&tp->rx_lock, lockflags);
> + if (ret && ret != -ENODEV) {
> + list_add_tail(&agg->list, next);
> + tasklet_schedule(&tp->tl);
> + }
> + continue;
> + }
> +
> + len_used = 0;
> + rx_desc = agg->head;
> + rx_data = agg->head;
> + smp_wmb();
> + pkt_len = le32_to_cpu(rx_desc->opts1) & RX_LEN_MASK;
> + len_used += sizeof(struct rx_desc) + pkt_len;
> +
> + while (urb->actual_length >= len_used) {
> + if (pkt_len < ETH_ZLEN)
> + break;
> +
> + pkt_len -= 4; /* CRC */
> + rx_data += sizeof(struct rx_desc);
> +
> + skb = netdev_alloc_skb_ip_align(netdev,
> pkt_len);
> + if (!skb) {
> + stats->rx_dropped++;
> + break;
> + }
> + memcpy(skb->data, rx_data, pkt_len);
> + skb_put(skb, pkt_len);
> + skb->protocol = eth_type_trans(skb, netdev);
> + netif_rx(skb);
> + stats->rx_packets++;
> + stats->rx_bytes += pkt_len;
> +
> + rx_data = rx_agg_align(rx_data + pkt_len + 4);
> + rx_desc = (struct rx_desc *)rx_data;
> + smp_wmb();
Against what is the memory barrier?
> + pkt_len = le32_to_cpu(rx_desc->opts1) &
> RX_LEN_MASK;
> + len_used = (int)(rx_data - (u8 *)agg->head);
> + len_used += sizeof(struct rx_desc) + pkt_len;
> + }
> +
> + ret = r8152_submit_rx(tp, agg, GFP_ATOMIC);
> + spin_lock_irqsave(&tp->rx_lock, lockflags);
> + if (ret && ret != -ENODEV) {
> + list_add_tail(&agg->list, next);
> + tasklet_schedule(&tp->tl);
> + }
> + }
> + spin_unlock_irqrestore(&tp->rx_lock, lockflags);
> +}
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
