[PATCH 1/2] mwifiex: resubmit failed to submit RX URBs in main thread

From: James Cao <redacted>

Current driver has 6 Rx data URBs. Once any packet received
kernel calls our callback, in which the same URB will be
resubmitted after Rx indication. In URB submission function a new
skb will be allocated since the previous one is passed to upper
layer (freed later). Since the skb is from a special pool (not
regular memory), skb allocation may fail when kernel holds a lot
of Rx packets on some low resource platforms. The URB will not be
resubmitted in this no free skb case. If driver fails to resubmit
all 6 URBs, Rx will stop. To cover this scenario check and
resubmit Rx URBs in main thread.

Signed-off-by: James Cao <redacted>
Signed-off-by: Cathy Luo <redacted>
Signed-off-by: Ganapathi Bhat <redacted>
---
 drivers/net/wireless/marvell/mwifiex/main.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/main.c b/drivers/net/wireless/marvell/mwifiex/main.c
index ee40b73..c78014b 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.c
+++ b/drivers/net/wireless/marvell/mwifiex/main.c

@@ -247,6 +247,7 @@ int mwifiex_main_process(struct mwifiex_adapter *adapter)
 {
 	int ret = 0;
 	unsigned long flags;
+	struct usb_card_rec *usb_card;
 
 	spin_lock_irqsave(&adapter->main_proc_lock, flags);
 

@@ -278,6 +279,16 @@ int mwifiex_main_process(struct mwifiex_adapter *adapter)
 			break;
 		}
 
+		/* Try to resubmit RX URB if sunmission failed earlier */
+		if (!atomic_read(&adapter->rx_pending) &&
+		    adapter->iface_type == MWIFIEX_USB) {
+			usb_card = adapter->card;
+			if (atomic_read(&usb_card->rx_data_urb_pending) <
+			    MWIFIEX_RX_DATA_URB &&
+			    adapter->if_ops.submit_rem_rx_urbs)
+				adapter->if_ops.submit_rem_rx_urbs(adapter);
+		}
+
 		/* Handle pending interrupt if any */
 		if (adapter->int_status) {
 			if (adapter->hs_activated)

-- 
1.9.1