r8152: replace tasklet with NAPI

Replace tasklet with NAPI.

Add rx_queue to queue the remaining rx packets if the number of the
rx packets is more than the request from poll().

Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index e519e6a..2e22442 100644 (file)
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -27,7 +27,7 @@
 #include <linux/usb/cdc.h>
 
 /* Version Information */
-#define DRIVER_VERSION "v1.07.0 (2014/10/09)"
+#define DRIVER_VERSION "v1.08.0 (2015/01/13)"
 #define DRIVER_AUTHOR "Realtek linux nic maintainers <nic_swsd@realtek.com>"
 #define DRIVER_DESC "Realtek RTL8152/RTL8153 Based USB Ethernet Adapters"
 #define MODULENAME "r8152"
@@ -448,6 +448,7 @@ enum rtl_register_content {
 #define RTL8152_RMS            (VLAN_ETH_FRAME_LEN + VLAN_HLEN)
 #define RTL8153_RMS            RTL8153_MAX_PACKET
 #define RTL8152_TX_TIMEOUT     (5 * HZ)
+#define RTL8152_NAPI_WEIGHT    64
 
 /* rtl8152 flags */
 enum rtl8152_flags {
@@ -457,7 +458,7 @@ enum rtl8152_flags {
        RTL8152_LINK_CHG,
        SELECTIVE_SUSPEND,
        PHY_RESET,
-       SCHEDULE_TASKLET,
+       SCHEDULE_NAPI,
 };
 
 /* Define these values to match your device */
@@ -549,14 +550,14 @@ struct tx_agg {
 struct r8152 {
        unsigned long flags;
        struct usb_device *udev;
-       struct tasklet_struct tl;
+       struct napi_struct napi;
        struct usb_interface *intf;
        struct net_device *netdev;
        struct urb *intr_urb;
        struct tx_agg tx_info[RTL8152_MAX_TX];
        struct rx_agg rx_info[RTL8152_MAX_RX];
        struct list_head rx_done, tx_free;
-       struct sk_buff_head tx_queue;
+       struct sk_buff_head tx_queue, rx_queue;
        spinlock_t rx_lock, tx_lock;
        struct delayed_work schedule;
        struct mii_if_info mii;
@@ -1062,7 +1063,7 @@ static void read_bulk_callback(struct urb *urb)
                spin_lock(&tp->rx_lock);
                list_add_tail(&agg->list, &tp->rx_done);
                spin_unlock(&tp->rx_lock);
-               tasklet_schedule(&tp->tl);
+               napi_schedule(&tp->napi);
                return;
        case -ESHUTDOWN:
                set_bit(RTL8152_UNPLUG, &tp->flags);
@@ -1126,7 +1127,7 @@ static void write_bulk_callback(struct urb *urb)
                return;
 
        if (!skb_queue_empty(&tp->tx_queue))
-               tasklet_schedule(&tp->tl);
+               napi_schedule(&tp->napi);
 }
 
 static void intr_callback(struct urb *urb)
@@ -1245,6 +1246,7 @@ static int alloc_all_mem(struct r8152 *tp)
        spin_lock_init(&tp->tx_lock);
        INIT_LIST_HEAD(&tp->tx_free);
        skb_queue_head_init(&tp->tx_queue);
+       skb_queue_head_init(&tp->rx_queue);
 
        for (i = 0; i < RTL8152_MAX_RX; i++) {
                buf = kmalloc_node(agg_buf_sz, GFP_KERNEL, node);
@@ -1649,13 +1651,32 @@ return_result:
        return checksum;
 }
 
-static void rx_bottom(struct r8152 *tp)
+static int rx_bottom(struct r8152 *tp, int budget)
 {
        unsigned long flags;
        struct list_head *cursor, *next, rx_queue;
+       int work_done = 0;
+
+       if (!skb_queue_empty(&tp->rx_queue)) {
+               while (work_done < budget) {
+                       struct sk_buff *skb = __skb_dequeue(&tp->rx_queue);
+                       struct net_device *netdev = tp->netdev;
+                       struct net_device_stats *stats = &netdev->stats;
+                       unsigned int pkt_len;
+
+                       if (!skb)
+                               break;
+
+                       pkt_len = skb->len;
+                       napi_gro_receive(&tp->napi, skb);
+                       work_done++;
+                       stats->rx_packets++;
+                       stats->rx_bytes += pkt_len;
+               }
+       }
 
        if (list_empty(&tp->rx_done))
-               return;
+               goto out1;
 
        INIT_LIST_HEAD(&rx_queue);
        spin_lock_irqsave(&tp->rx_lock, flags);
@@ -1708,9 +1729,14 @@ static void rx_bottom(struct r8152 *tp)
                        skb_put(skb, pkt_len);
                        skb->protocol = eth_type_trans(skb, netdev);
                        rtl_rx_vlan_tag(rx_desc, skb);
-                       netif_receive_skb(skb);
-                       stats->rx_packets++;
-                       stats->rx_bytes += pkt_len;
+                       if (work_done < budget) {
+                               napi_gro_receive(&tp->napi, skb);
+                               work_done++;
+                               stats->rx_packets++;
+                               stats->rx_bytes += pkt_len;
+                       } else {
+                               __skb_queue_tail(&tp->rx_queue, skb);
+                       }
 
 find_next_rx:
                        rx_data = rx_agg_align(rx_data + pkt_len + CRC_SIZE);
@@ -1722,6 +1748,9 @@ find_next_rx:
 submit:
                r8152_submit_rx(tp, agg, GFP_ATOMIC);
        }
+
+out1:
+       return work_done;
 }
 
 static void tx_bottom(struct r8152 *tp)
@@ -1761,12 +1790,8 @@ static void tx_bottom(struct r8152 *tp)
        } while (res == 0);
 }
 
-static void bottom_half(unsigned long data)
+static void bottom_half(struct r8152 *tp)
 {
-       struct r8152 *tp;
-
-       tp = (struct r8152 *)data;
-
        if (test_bit(RTL8152_UNPLUG, &tp->flags))
                return;
 
@@ -1778,12 +1803,28 @@ static void bottom_half(unsigned long data)
        if (!netif_carrier_ok(tp->netdev))
                return;
 
-       clear_bit(SCHEDULE_TASKLET, &tp->flags);
+       clear_bit(SCHEDULE_NAPI, &tp->flags);
 
-       rx_bottom(tp);
        tx_bottom(tp);
 }
 
+static int r8152_poll(struct napi_struct *napi, int budget)
+{
+       struct r8152 *tp = container_of(napi, struct r8152, napi);
+       int work_done;
+
+       work_done = rx_bottom(tp, budget);
+       bottom_half(tp);
+
+       if (work_done < budget) {
+               napi_complete(napi);
+               if (!list_empty(&tp->rx_done))
+                       napi_schedule(napi);
+       }
+
+       return work_done;
+}
+
 static
 int r8152_submit_rx(struct r8152 *tp, struct rx_agg *agg, gfp_t mem_flags)
 {
@@ -1810,7 +1851,11 @@ int r8152_submit_rx(struct r8152 *tp, struct rx_agg *agg, gfp_t mem_flags)
                spin_lock_irqsave(&tp->rx_lock, flags);
                list_add_tail(&agg->list, &tp->rx_done);
                spin_unlock_irqrestore(&tp->rx_lock, flags);
-               tasklet_schedule(&tp->tl);
+
+               netif_err(tp, rx_err, tp->netdev,
+                         "Couldn't submit rx[%p], ret = %d\n", agg, ret);
+
+               napi_schedule(&tp->napi);
        }
 
        return ret;
@@ -1929,11 +1974,11 @@ static netdev_tx_t rtl8152_start_xmit(struct sk_buff *skb,
 
        if (!list_empty(&tp->tx_free)) {
                if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) {
-                       set_bit(SCHEDULE_TASKLET, &tp->flags);
+                       set_bit(SCHEDULE_NAPI, &tp->flags);
                        schedule_delayed_work(&tp->schedule, 0);
                } else {
                        usb_mark_last_busy(tp->udev);
-                       tasklet_schedule(&tp->tl);
+                       napi_schedule(&tp->napi);
                }
        } else if (skb_queue_len(&tp->tx_queue) > tp->tx_qlen) {
                netif_stop_queue(netdev);
@@ -2012,6 +2057,7 @@ static int rtl_start_rx(struct r8152 *tp)
 {
        int i, ret = 0;
 
+       napi_disable(&tp->napi);
        INIT_LIST_HEAD(&tp->rx_done);
        for (i = 0; i < RTL8152_MAX_RX; i++) {
                INIT_LIST_HEAD(&tp->rx_info[i].list);
@@ -2019,6 +2065,7 @@ static int rtl_start_rx(struct r8152 *tp)
                if (ret)
                        break;
        }
+       napi_enable(&tp->napi);
 
        if (ret && ++i < RTL8152_MAX_RX) {
                struct list_head rx_queue;
@@ -2049,6 +2096,9 @@ static int rtl_stop_rx(struct r8152 *tp)
        for (i = 0; i < RTL8152_MAX_RX; i++)
                usb_kill_urb(tp->rx_info[i].urb);
 
+       while (!skb_queue_empty(&tp->rx_queue))
+               dev_kfree_skb(__skb_dequeue(&tp->rx_queue));
+
        return 0;
 }
 
@@ -2884,9 +2934,9 @@ static void set_carrier(struct r8152 *tp)
        } else {
                if (tp->speed & LINK_STATUS) {
                        netif_carrier_off(netdev);
-                       tasklet_disable(&tp->tl);
+                       napi_disable(&tp->napi);
                        tp->rtl_ops.disable(tp);
-                       tasklet_enable(&tp->tl);
+                       napi_enable(&tp->napi);
                }
        }
        tp->speed = speed;
@@ -2919,10 +2969,11 @@ static void rtl_work_func_t(struct work_struct *work)
        if (test_bit(RTL8152_SET_RX_MODE, &tp->flags))
                _rtl8152_set_rx_mode(tp->netdev);
 
-       if (test_bit(SCHEDULE_TASKLET, &tp->flags) &&
+       /* don't schedule napi before linking */
+       if (test_bit(SCHEDULE_NAPI, &tp->flags) &&
            (tp->speed & LINK_STATUS)) {
-               clear_bit(SCHEDULE_TASKLET, &tp->flags);
-               tasklet_schedule(&tp->tl);
+               clear_bit(SCHEDULE_NAPI, &tp->flags);
+               napi_schedule(&tp->napi);
        }
 
        if (test_bit(PHY_RESET, &tp->flags))
@@ -2983,7 +3034,7 @@ static int rtl8152_open(struct net_device *netdev)
                           res);
                free_all_mem(tp);
        } else {
-               tasklet_enable(&tp->tl);
+               napi_enable(&tp->napi);
        }
 
        mutex_unlock(&tp->control);
@@ -2999,7 +3050,7 @@ static int rtl8152_close(struct net_device *netdev)
        struct r8152 *tp = netdev_priv(netdev);
        int res = 0;
 
-       tasklet_disable(&tp->tl);
+       napi_disable(&tp->napi);
        clear_bit(WORK_ENABLE, &tp->flags);
        usb_kill_urb(tp->intr_urb);
        cancel_delayed_work_sync(&tp->schedule);
@@ -3008,6 +3059,7 @@ static int rtl8152_close(struct net_device *netdev)
        res = usb_autopm_get_interface(tp->intf);
        if (res < 0) {
                rtl_drop_queued_tx(tp);
+               rtl_stop_rx(tp);
        } else {
                mutex_lock(&tp->control);
 
@@ -3263,7 +3315,7 @@ static int rtl8152_suspend(struct usb_interface *intf, pm_message_t message)
        if (netif_running(netdev) && test_bit(WORK_ENABLE, &tp->flags)) {
                clear_bit(WORK_ENABLE, &tp->flags);
                usb_kill_urb(tp->intr_urb);
-               tasklet_disable(&tp->tl);
+               napi_disable(&tp->napi);
                if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) {
                        rtl_stop_rx(tp);
                        rtl_runtime_suspend_enable(tp, true);
@@ -3271,7 +3323,7 @@ static int rtl8152_suspend(struct usb_interface *intf, pm_message_t message)
                        cancel_delayed_work_sync(&tp->schedule);
                        tp->rtl_ops.down(tp);
                }
-               tasklet_enable(&tp->tl);
+               napi_enable(&tp->napi);
        }
 out1:
        mutex_unlock(&tp->control);
@@ -3855,7 +3907,6 @@ static int rtl8152_probe(struct usb_interface *intf,
        if (ret)
                goto out;
 
-       tasklet_init(&tp->tl, bottom_half, (unsigned long)tp);
        mutex_init(&tp->control);
        INIT_DELAYED_WORK(&tp->schedule, rtl_work_func_t);
 
@@ -3891,6 +3942,7 @@ static int rtl8152_probe(struct usb_interface *intf,
        set_ethernet_addr(tp);
 
        usb_set_intfdata(intf, tp);
+       netif_napi_add(netdev, &tp->napi, r8152_poll, RTL8152_NAPI_WEIGHT);
 
        ret = register_netdev(netdev);
        if (ret != 0) {
@@ -3904,15 +3956,13 @@ static int rtl8152_probe(struct usb_interface *intf,
        else
                device_set_wakeup_enable(&udev->dev, false);
 
-       tasklet_disable(&tp->tl);
-
        netif_info(tp, probe, netdev, "%s\n", DRIVER_VERSION);
 
        return 0;
 
 out1:
+       netif_napi_del(&tp->napi);
        usb_set_intfdata(intf, NULL);
-       tasklet_kill(&tp->tl);
 out:
        free_netdev(netdev);
        return ret;
@@ -3929,7 +3979,7 @@ static void rtl8152_disconnect(struct usb_interface *intf)
                if (udev->state == USB_STATE_NOTATTACHED)
                        set_bit(RTL8152_UNPLUG, &tp->flags);
 
-               tasklet_kill(&tp->tl);
+               netif_napi_del(&tp->napi);
                unregister_netdev(tp->netdev);
                tp->rtl_ops.unload(tp);
                free_netdev(tp->netdev);