netdev - [net-next RFC v3 1/7] net: ravb: Simplify poll & receive functions

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Message-Id: <20240415094804.8016-2-paul.barker.ct@bp.renesas.com>
Date: Mon, 15 Apr 2024 10:47:58 +0100
From: Paul Barker <paul.barker.ct@...renesas.com>
To: Sergey Shtylyov <s.shtylyov@....ru>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>
Cc: Paul Barker <paul.barker.ct@...renesas.com>,
	Niklas Söderlund <niklas.soderlund+renesas@...natech.se>,
	Geert Uytterhoeven <geert+renesas@...der.be>,
	netdev@...r.kernel.org,
	linux-renesas-soc@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [net-next RFC v3 1/7] net: ravb: Simplify poll & receive functions

We don't need to pass the work budget to ravb_rx() by reference, it's
cleaner to pass this by value and return the amount of work done. This
allows us to simplify the ravb_poll() function and use the common
`work_done` variable name seen in other network drivers for consistency
and ease of understanding.

This is a pure refactor and should not affect behaviour.

Signed-off-by: Paul Barker <paul.barker.ct@...renesas.com>
---
 drivers/net/ethernet/renesas/ravb.h      |  2 +-
 drivers/net/ethernet/renesas/ravb_main.c | 29 ++++++++++--------------
 2 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index b48935ec7e28..71de2a7aa27c 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -1039,7 +1039,7 @@ struct ravb_ptp {
 };
 
 struct ravb_hw_info {
-	bool (*receive)(struct net_device *ndev, int *quota, int q);
+	int (*receive)(struct net_device *ndev, int budget, int q);
 	void (*set_rate)(struct net_device *ndev);
 	int (*set_feature)(struct net_device *ndev, netdev_features_t features);
 	int (*dmac_init)(struct net_device *ndev);
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index fd2679ce4e3d..33f8043143c1 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -759,7 +759,7 @@ static struct sk_buff *ravb_get_skb_gbeth(struct net_device *ndev, int entry,
 }
 
 /* Packet receive function for Gigabit Ethernet */
-static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q)
+static int ravb_rx_gbeth(struct net_device *ndev, int budget, int q)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
 	const struct ravb_hw_info *info = priv->info;
@@ -778,7 +778,7 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q)
 	limit = priv->dirty_rx[q] + priv->num_rx_ring[q] - priv->cur_rx[q];
 	stats = &priv->stats[q];
 
-	for (i = 0; i < limit && rx_packets < *quota; i++, priv->cur_rx[q]++) {
+	for (i = 0; i < limit && rx_packets < budget; i++, priv->cur_rx[q]++) {
 		entry = priv->cur_rx[q] % priv->num_rx_ring[q];
 		desc = &priv->rx_ring[q].desc[entry];
 		if (desc->die_dt == DT_FEMPTY)
@@ -881,13 +881,11 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q)
 		desc->die_dt = DT_FEMPTY;
 	}
 
-	stats->rx_packets += rx_packets;
-	*quota -= rx_packets;
-	return *quota == 0;
+	return rx_packets;
 }
 
 /* Packet receive function for Ethernet AVB */
-static bool ravb_rx_rcar(struct net_device *ndev, int *quota, int q)
+static int ravb_rx_rcar(struct net_device *ndev, int budget, int q)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
 	const struct ravb_hw_info *info = priv->info;
@@ -904,7 +902,7 @@ static bool ravb_rx_rcar(struct net_device *ndev, int *quota, int q)
 	int i;
 
 	limit = priv->dirty_rx[q] + priv->num_rx_ring[q] - priv->cur_rx[q];
-	for (i = 0; i < limit && rx_packets < *quota; i++, priv->cur_rx[q]++) {
+	for (i = 0; i < limit && rx_packets < budget; i++, priv->cur_rx[q]++) {
 		entry = priv->cur_rx[q] % priv->num_rx_ring[q];
 		desc = &priv->rx_ring[q].ex_desc[entry];
 		if (desc->die_dt == DT_FEMPTY)
@@ -992,18 +990,16 @@ static bool ravb_rx_rcar(struct net_device *ndev, int *quota, int q)
 		desc->die_dt = DT_FEMPTY;
 	}
 
-	stats->rx_packets += rx_packets;
-	*quota -= rx_packets;
-	return *quota == 0;
+	return rx_packets;
 }
 
 /* Packet receive function for Ethernet AVB */
-static bool ravb_rx(struct net_device *ndev, int *quota, int q)
+static int ravb_rx(struct net_device *ndev, int budget, int q)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
 	const struct ravb_hw_info *info = priv->info;
 
-	return info->receive(ndev, quota, q);
+	return info->receive(ndev, budget, q);
 }
 
 static void ravb_rcv_snd_disable(struct net_device *ndev)
@@ -1320,13 +1316,12 @@ static int ravb_poll(struct napi_struct *napi, int budget)
 	unsigned long flags;
 	int q = napi - priv->napi;
 	int mask = BIT(q);
-	int quota = budget;
-	bool unmask;
+	int work_done;
 
 	/* Processing RX Descriptor Ring */
 	/* Clear RX interrupt */
 	ravb_write(ndev, ~(mask | RIS0_RESERVED), RIS0);
-	unmask = !ravb_rx(ndev, &quota, q);
+	work_done = ravb_rx(ndev, budget, q);
 
 	/* Processing TX Descriptor Ring */
 	spin_lock_irqsave(&priv->lock, flags);
@@ -1345,7 +1340,7 @@ static int ravb_poll(struct napi_struct *napi, int budget)
 	if (priv->rx_fifo_errors != ndev->stats.rx_fifo_errors)
 		ndev->stats.rx_fifo_errors = priv->rx_fifo_errors;
 
-	if (!unmask)
+	if (work_done == budget)
 		goto out;
 
 	napi_complete(napi);
@@ -1362,7 +1357,7 @@ static int ravb_poll(struct napi_struct *napi, int budget)
 	spin_unlock_irqrestore(&priv->lock, flags);
 
 out:
-	return budget - quota;
+	return work_done;
 }
 
 static void ravb_set_duplex_gbeth(struct net_device *ndev)
-- 
2.39.2