6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
[ Upstream commit c4f922e86c8e0f7c5fe94e0547e9835fc9711f08 ]
Add spin lock protection for irq {un}mask registers' control.
After napi_complete_done() and this protection were applied,
a lot of redundant interrupts no longer occur.
For example: when "iperf3 -c <ipaddr> -R" on R-Car S4-8 Spider
Before the patches are applied: about 800,000 times happened
After the patches were applied: about 100,000 times happened
Fixes: 3590918b5d07 ("net: ethernet: renesas: Add support for "Ethernet Switch"")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Stable-dep-of: a0c55bba0d0d ("rswitch: Fix PHY station management clock setting")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/renesas/rswitch.c | 12 ++++++++++++
drivers/net/ethernet/renesas/rswitch.h | 2 ++
2 files changed, 14 insertions(+)
diff --git a/drivers/net/ethernet/renesas/rswitch.c b/drivers/net/ethernet/renesas/rswitch.c
index 449ed1f5624c9..215854812f80a 100644
--- a/drivers/net/ethernet/renesas/rswitch.c
+++ b/drivers/net/ethernet/renesas/rswitch.c
@@ -799,6 +799,7 @@ static int rswitch_poll(struct napi_struct *napi, int budget)
struct net_device *ndev = napi->dev;
struct rswitch_private *priv;
struct rswitch_device *rdev;
+ unsigned long flags;
int quota = budget;
rdev = netdev_priv(ndev);
@@ -817,8 +818,10 @@ static int rswitch_poll(struct napi_struct *napi, int budget)
netif_wake_subqueue(ndev, 0);
if (napi_complete_done(napi, budget - quota)) {
+ spin_lock_irqsave(&priv->lock, flags);
rswitch_enadis_data_irq(priv, rdev->tx_queue->index, true);
rswitch_enadis_data_irq(priv, rdev->rx_queue->index, true);
+ spin_unlock_irqrestore(&priv->lock, flags);
}
out:
@@ -835,8 +838,10 @@ static void rswitch_queue_interrupt(struct net_device *ndev)
struct rswitch_device *rdev = netdev_priv(ndev);
if (napi_schedule_prep(&rdev->napi)) {
+ spin_lock(&rdev->priv->lock);
rswitch_enadis_data_irq(rdev->priv, rdev->tx_queue->index, false);
rswitch_enadis_data_irq(rdev->priv, rdev->rx_queue->index, false);
+ spin_unlock(&rdev->priv->lock);
__napi_schedule(&rdev->napi);
}
}
@@ -1430,14 +1435,17 @@ static void rswitch_ether_port_deinit_all(struct rswitch_private *priv)
static int rswitch_open(struct net_device *ndev)
{
struct rswitch_device *rdev = netdev_priv(ndev);
+ unsigned long flags;
phy_start(ndev->phydev);
napi_enable(&rdev->napi);
netif_start_queue(ndev);
+ spin_lock_irqsave(&rdev->priv->lock, flags);
rswitch_enadis_data_irq(rdev->priv, rdev->tx_queue->index, true);
rswitch_enadis_data_irq(rdev->priv, rdev->rx_queue->index, true);
+ spin_unlock_irqrestore(&rdev->priv->lock, flags);
if (bitmap_empty(rdev->priv->opened_ports, RSWITCH_NUM_PORTS))
iowrite32(GWCA_TS_IRQ_BIT, rdev->priv->addr + GWTSDIE);
@@ -1451,6 +1459,7 @@ static int rswitch_stop(struct net_device *ndev)
{
struct rswitch_device *rdev = netdev_priv(ndev);
struct rswitch_gwca_ts_info *ts_info, *ts_info2;
+ unsigned long flags;
netif_tx_stop_all_queues(ndev);
bitmap_clear(rdev->priv->opened_ports, rdev->port, 1);
@@ -1466,8 +1475,10 @@ static int rswitch_stop(struct net_device *ndev)
kfree(ts_info);
}
+ spin_lock_irqsave(&rdev->priv->lock, flags);
rswitch_enadis_data_irq(rdev->priv, rdev->tx_queue->index, false);
rswitch_enadis_data_irq(rdev->priv, rdev->rx_queue->index, false);
+ spin_unlock_irqrestore(&rdev->priv->lock, flags);
phy_stop(ndev->phydev);
napi_disable(&rdev->napi);
@@ -1869,6 +1880,7 @@ static int renesas_eth_sw_probe(struct platform_device *pdev)
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
+ spin_lock_init(&priv->lock);
priv->ptp_priv = rcar_gen4_ptp_alloc(pdev);
if (!priv->ptp_priv)
diff --git a/drivers/net/ethernet/renesas/rswitch.h b/drivers/net/ethernet/renesas/rswitch.h
index bb9ed971a97ca..9740398067140 100644
--- a/drivers/net/ethernet/renesas/rswitch.h
+++ b/drivers/net/ethernet/renesas/rswitch.h
@@ -1011,6 +1011,8 @@ struct rswitch_private {
struct rswitch_etha etha[RSWITCH_NUM_PORTS];
struct rswitch_mfwd mfwd;
+ spinlock_t lock; /* lock interrupt registers' control */
+
bool gwca_halt;
};
--
2.40.1
