ath9k_htc: Increase URB count for REG_IN pipe

Using a single URB for receiving WMI events is
insufficient, increase it to 64 to not lose
WMI events in high throughput situations.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 61 insertions, 42 deletions

diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
index e252576760d1..0b63a48462c7 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -566,6 +566,9 @@ static void ath9k_hif_usb_reg_in_cb(struct urb *urb)
         case -ESHUTDOWN:
                 goto free;
         default:
+                skb_reset_tail_pointer(skb);
+                skb_trim(skb, 0);
+
                 goto resubmit;
         }
 
@@ -590,23 +593,15 @@ static void ath9k_hif_usb_reg_in_cb(struct urb *urb)
                                                  USB_REG_IN_PIPE),
                                  nskb->data, MAX_REG_IN_BUF_SIZE,
                                  ath9k_hif_usb_reg_in_cb, nskb);
-
-                ret = usb_submit_urb(urb, GFP_ATOMIC);
-                if (ret) {
-                        kfree_skb(nskb);
-                        urb->context = NULL;
-                }
-
-                return;
         }
 
 resubmit:
-        skb_reset_tail_pointer(skb);
-        skb_trim(skb, 0);
-
+        usb_anchor_urb(urb, &hif_dev->reg_in_submitted);
         ret = usb_submit_urb(urb, GFP_ATOMIC);
-        if (ret)
+        if (ret) {
+                usb_unanchor_urb(urb);
                 goto free;
+        }
 
         return;
 free:
@@ -747,43 +742,67 @@ err_urb:
         return ret;
 }
 
-static void ath9k_hif_usb_dealloc_reg_in_urb(struct hif_device_usb *hif_dev)
+static void ath9k_hif_usb_dealloc_reg_in_urbs(struct hif_device_usb *hif_dev)
 {
-        if (hif_dev->reg_in_urb) {
-                usb_kill_urb(hif_dev->reg_in_urb);
-                if (hif_dev->reg_in_urb->context)
-                        kfree_skb((void *)hif_dev->reg_in_urb->context);
-                usb_free_urb(hif_dev->reg_in_urb);
-                hif_dev->reg_in_urb = NULL;
-        }
+        usb_kill_anchored_urbs(&hif_dev->reg_in_submitted);
 }
 
-static int ath9k_hif_usb_alloc_reg_in_urb(struct hif_device_usb *hif_dev)
+static int ath9k_hif_usb_alloc_reg_in_urbs(struct hif_device_usb *hif_dev)
 {
-        struct sk_buff *skb;
+        struct urb *urb = NULL;
+        struct sk_buff *skb = NULL;
+        int i, ret;
 
-        hif_dev->reg_in_urb = usb_alloc_urb(0, GFP_KERNEL);
-        if (hif_dev->reg_in_urb == NULL)
-                return -ENOMEM;
+        init_usb_anchor(&hif_dev->reg_in_submitted);
 
-        skb = alloc_skb(MAX_REG_IN_BUF_SIZE, GFP_KERNEL);
-        if (!skb)
-                goto err;
+        for (i = 0; i < MAX_REG_IN_URB_NUM; i++) {
 
-        usb_fill_bulk_urb(hif_dev->reg_in_urb, hif_dev->udev,
-                         usb_rcvbulkpipe(hif_dev->udev,
-                                         USB_REG_IN_PIPE),
-                         skb->data, MAX_REG_IN_BUF_SIZE,
-                         ath9k_hif_usb_reg_in_cb, skb);
+                /* Allocate URB */
+                urb = usb_alloc_urb(0, GFP_KERNEL);
+                if (urb == NULL) {
+                        ret = -ENOMEM;
+                        goto err_urb;
+                }
 
-        if (usb_submit_urb(hif_dev->reg_in_urb, GFP_KERNEL) != 0)
-                goto err;
+                /* Allocate buffer */
+                skb = alloc_skb(MAX_REG_IN_BUF_SIZE, GFP_KERNEL);
+                if (!skb) {
+                        ret = -ENOMEM;
+                        goto err_skb;
+                }
+
+                usb_fill_bulk_urb(urb, hif_dev->udev,
+                                  usb_rcvbulkpipe(hif_dev->udev,
+                                                  USB_REG_IN_PIPE),
+                                  skb->data, MAX_REG_IN_BUF_SIZE,
+                                  ath9k_hif_usb_reg_in_cb, skb);
+
+                /* Anchor URB */
+                usb_anchor_urb(urb, &hif_dev->reg_in_submitted);
+
+                /* Submit URB */
+                ret = usb_submit_urb(urb, GFP_KERNEL);
+                if (ret) {
+                        usb_unanchor_urb(urb);
+                        goto err_submit;
+                }
+
+                /*
+                 * Drop reference count.
+                 * This ensures that the URB is freed when killing them.
+                 */
+                usb_free_urb(urb);
+        }
 
         return 0;
 
-err:
-        ath9k_hif_usb_dealloc_reg_in_urb(hif_dev);
-        return -ENOMEM;
+err_submit:
+        kfree_skb(skb);
+err_skb:
+        usb_free_urb(urb);
+err_urb:
+        ath9k_hif_usb_dealloc_reg_in_urbs(hif_dev);
+        return ret;
 }
 
 static int ath9k_hif_usb_alloc_urbs(struct hif_device_usb *hif_dev)
@@ -800,7 +819,7 @@ static int ath9k_hif_usb_alloc_urbs(struct hif_device_usb *hif_dev)
                 goto err_rx;
 
         /* Register Read */
-        if (ath9k_hif_usb_alloc_reg_in_urb(hif_dev) < 0)
+        if (ath9k_hif_usb_alloc_reg_in_urbs(hif_dev) < 0)
                 goto err_reg;
 
         return 0;
@@ -815,7 +834,7 @@ err:
 static void ath9k_hif_usb_dealloc_urbs(struct hif_device_usb *hif_dev)
 {
         usb_kill_anchored_urbs(&hif_dev->regout_submitted);
-        ath9k_hif_usb_dealloc_reg_in_urb(hif_dev);
+        ath9k_hif_usb_dealloc_reg_in_urbs(hif_dev);
         ath9k_hif_usb_dealloc_tx_urbs(hif_dev);
         ath9k_hif_usb_dealloc_rx_urbs(hif_dev);
 }
diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.h b/drivers/net/wireless/ath/ath9k/hif_usb.h
index f82b32bbf4e2..8b98d646e91a 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.h
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.h
@@ -40,7 +40,7 @@
 #define MAX_PKT_NUM_IN_TRANSFER 10
 
 #define MAX_REG_OUT_URB_NUM  1
-#define MAX_REG_OUT_BUF_NUM  8
+#define MAX_REG_IN_URB_NUM   64
 
 #define MAX_REG_IN_BUF_SIZE 64
 
@@ -90,9 +90,9 @@ struct hif_device_usb {
         const struct firmware *firmware;
         struct htc_target *htc_handle;
         struct hif_usb_tx tx;
-        struct urb *reg_in_urb;
         struct usb_anchor regout_submitted;
         struct usb_anchor rx_submitted;
+        struct usb_anchor reg_in_submitted;
         struct sk_buff *remain_skb;
         const char *fw_name;
         int rx_remain_len;