rsi: improve RX handling in SDIO interface

Currently, RX packets are handled in interrupt context in SDIO
interface. To improve the efficiency of processing RX packets,
RX thread and RX skb queues are introduced.
When the packet is read from device, driver prepares skb, add to
RX queue and trigger RX thread event. RX thread processes the
packets from RX queue.

Signed-off-by: Prameela Rani Garnepudi <prameela.j04cs@gmail.com>
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

1 files changed, 51 insertions, 13 deletions

diff --git a/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c b/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
index 6e74261186c6..612c211e21a1 100644
--- a/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
+++ b/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
@@ -60,6 +60,43 @@ int rsi_sdio_master_access_msword(struct rsi_hw *adapter, u16 ms_word)
 	return status;
 }
 
+void rsi_sdio_rx_thread(struct rsi_common *common)
+{
+	struct rsi_hw *adapter = common->priv;
+	struct rsi_91x_sdiodev *sdev = adapter->rsi_dev;
+	struct sk_buff *skb;
+	int status;
+
+	do {
+		rsi_wait_event(&sdev->rx_thread.event, EVENT_WAIT_FOREVER);
+		rsi_reset_event(&sdev->rx_thread.event);
+
+		while (true) {
+			if (atomic_read(&sdev->rx_thread.thread_done))
+				goto out;
+
+			skb = skb_dequeue(&sdev->rx_q.head);
+			if (!skb)
+				break;
+			if (sdev->rx_q.num_rx_pkts > 0)
+				sdev->rx_q.num_rx_pkts--;
+			status = rsi_read_pkt(common, skb->data, skb->len);
+			if (status) {
+				rsi_dbg(ERR_ZONE, "Failed to read the packet\n");
+				dev_kfree_skb(skb);
+				break;
+			}
+			dev_kfree_skb(skb);
+		}
+	} while (1);
+
+out:
+	rsi_dbg(INFO_ZONE, "%s: Terminated SDIO RX thread\n", __func__);
+	skb_queue_purge(&sdev->rx_q.head);
+	atomic_inc(&sdev->rx_thread.thread_done);
+	complete_and_exit(&sdev->rx_thread.completion, 0);
+}
+
 /**
  * rsi_process_pkt() - This Function reads rx_blocks register and figures out
  *		       the size of the rx pkt.
@@ -76,6 +113,10 @@ static int rsi_process_pkt(struct rsi_common *common)
 	u32 rcv_pkt_len = 0;
 	int status = 0;
 	u8 value = 0;
+	struct sk_buff *skb;
+
+	if (dev->rx_q.num_rx_pkts >= RSI_MAX_RX_PKTS)
+		return 0;
 
 	num_blks = ((adapter->interrupt_status & 1) |
 			((adapter->interrupt_status >> RECV_NUM_BLOCKS) << 1));
@@ -103,27 +144,24 @@ static int rsi_process_pkt(struct rsi_common *common)
 
 	rcv_pkt_len = (num_blks * 256);
 
-	common->rx_data_pkt = kzalloc(rcv_pkt_len, GFP_KERNEL);
-	if (!common->rx_data_pkt) {
-		rsi_dbg(ERR_ZONE, "%s: Failed in memory allocation\n",
-			__func__);
+	skb = dev_alloc_skb(rcv_pkt_len);
+	if (!skb)
 		return -ENOMEM;
-	}
 
-	status = rsi_sdio_host_intf_read_pkt(adapter,
-					     common->rx_data_pkt,
-					     rcv_pkt_len);
+	status = rsi_sdio_host_intf_read_pkt(adapter, skb->data, rcv_pkt_len);
 	if (status) {
 		rsi_dbg(ERR_ZONE, "%s: Failed to read packet from card\n",
 			__func__);
-		goto fail;
+		dev_kfree_skb(skb);
+		return status;
 	}
+	skb_put(skb, rcv_pkt_len);
+	skb_queue_tail(&dev->rx_q.head, skb);
+	dev->rx_q.num_rx_pkts++;
 
-	status = rsi_read_pkt(common, common->rx_data_pkt, rcv_pkt_len);
+	rsi_set_event(&dev->rx_thread.event);
 
-fail:
-	kfree(common->rx_data_pkt);
-	return status;
+	return 0;
 }
 
 /**