[openwrt/openwrt] bmips: improve rx loop

[LEDE Commits]

noltari pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/6276dad6caadc6dc96bb6fb54d432bc8d8455a0e

commit 6276dad6caadc6dc96bb6fb54d432bc8d8455a0e
Author: Sieng Piaw Liew <liew.s.piaw at gmail.com>
AuthorDate: Thu Jun 23 14:48:42 2022 +0800

    bmips: improve rx loop
    
    Use existing rx processed count to track against budget, thereby making
    budget decrement operation redundant.
    rx_desc_count can be calculated outside the rx loop, making the loop a
    bit smaller.
    
    Signed-off-by: Sieng Piaw Liew <liew.s.piaw at gmail.com>
---
 .../linux/bmips/files/drivers/net/ethernet/broadcom/bcm6368-enetsw.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/target/linux/bmips/files/drivers/net/ethernet/broadcom/bcm6368-enetsw.c b/target/linux/bmips/files/drivers/net/ethernet/broadcom/bcm6368-enetsw.c
index 962f9ac887..04884a122d 100644
--- a/target/linux/bmips/files/drivers/net/ethernet/broadcom/bcm6368-enetsw.c
+++ b/target/linux/bmips/files/drivers/net/ethernet/broadcom/bcm6368-enetsw.c
@@ -367,7 +367,6 @@ static int bcm6368_enetsw_receive_queue(struct net_device *dev, int budget)
 		priv->rx_curr_desc++;
 		if (priv->rx_curr_desc == priv->rx_ring_size)
 			priv->rx_curr_desc = 0;
-		priv->rx_desc_count--;
 
 		/* if the packet does not have start of packet _and_
 		 * end of packet flag set, then just recycle it */
@@ -420,7 +419,9 @@ static int bcm6368_enetsw_receive_queue(struct net_device *dev, int budget)
 		dev->stats.rx_packets++;
 		dev->stats.rx_bytes += len;
 		netif_receive_skb(skb);
-	} while (--budget > 0);
+	} while (processed < budget);
+
+	priv->rx_desc_count -= processed;
 
 	if (processed || !priv->rx_desc_count) {
 		bcm6368_enetsw_refill_rx(dev, true);