[PATCH RT 1/2] net: gianfar: do not disable interrupts

[Sebastian Andrzej Siewior]

each per-queue lock is taken with spin_lock_irqsave() except in the case
where all of them are taken for some kind of serialisation. As an
optimisation local_irq_save() is used so that lock_tx_qs() and
lock_rx_qs() can use just the spin_lock() variant instead.
On RT local_irq_save() behaves differently so we use the nort()
variant.
Lockdep screems easily by "ethtool -K eth0 rx off tx off"

What remains is missing lockdep annotation that makes lockdep think
lock_tx_qs() may cause a dead lock.

Cc: stable-rt@xxxxxxxxxxxxxxx
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
 drivers/net/ethernet/freescale/gianfar.c         | 16 ++++++++--------
 drivers/net/ethernet/freescale/gianfar_ethtool.c |  8 ++++----
 drivers/net/ethernet/freescale/gianfar_sysfs.c   | 24 ++++++++++++------------
 3 files changed, 24 insertions(+), 24 deletions(-)

diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c
index de10ff3..8f1afda 100644
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -1301,7 +1301,7 @@ static int gfar_suspend(struct device *dev)
 
 	if (netif_running(ndev)) {
 
-		local_irq_save(flags);
+		local_irq_save_nort(flags);
 		lock_tx_qs(priv);
 		lock_rx_qs(priv);
 
@@ -1319,7 +1319,7 @@ static int gfar_suspend(struct device *dev)
 
 		unlock_rx_qs(priv);
 		unlock_tx_qs(priv);
-		local_irq_restore(flags);
+		local_irq_restore_nort(flags);
 
 		disable_napi(priv);
 
@@ -1361,7 +1361,7 @@ static int gfar_resume(struct device *dev)
 	/* Disable Magic Packet mode, in case something
 	 * else woke us up.
 	 */
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_tx_qs(priv);
 	lock_rx_qs(priv);
 
@@ -1373,7 +1373,7 @@ static int gfar_resume(struct device *dev)
 
 	unlock_rx_qs(priv);
 	unlock_tx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	netif_device_attach(ndev);
 
@@ -2387,7 +2387,7 @@ void gfar_vlan_mode(struct net_device *dev, netdev_features_t features)
 	u32 tempval;
 
 	regs = priv->gfargrp[0].regs;
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_rx_qs(priv);
 
 	if (features & NETIF_F_HW_VLAN_CTAG_TX) {
@@ -2420,7 +2420,7 @@ void gfar_vlan_mode(struct net_device *dev, netdev_features_t features)
 	gfar_change_mtu(dev, dev->mtu);
 
 	unlock_rx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 }
 
 static int gfar_change_mtu(struct net_device *dev, int new_mtu)
@@ -3381,14 +3381,14 @@ static irqreturn_t gfar_error(int irq, void *grp_id)
 			dev->stats.tx_dropped++;
 			atomic64_inc(&priv->extra_stats.tx_underrun);
 
-			local_irq_save(flags);
+			local_irq_save_nort(flags);
 			lock_tx_qs(priv);
 
 			/* Reactivate the Tx Queues */
 			gfar_write(&regs->tstat, gfargrp->tstat);
 
 			unlock_tx_qs(priv);
-			local_irq_restore(flags);
+			local_irq_restore_nort(flags);
 		}
 		netif_dbg(priv, tx_err, dev, "Transmit Error\n");
 	}
diff --git a/drivers/net/ethernet/freescale/gianfar_ethtool.c b/drivers/net/ethernet/freescale/gianfar_ethtool.c
index d3d7ede..95a1f62 100644
--- a/drivers/net/ethernet/freescale/gianfar_ethtool.c
+++ b/drivers/net/ethernet/freescale/gianfar_ethtool.c
@@ -501,7 +501,7 @@ static int gfar_sringparam(struct net_device *dev,
 		/* Halt TX and RX, and process the frames which
 		 * have already been received
 		 */
-		local_irq_save(flags);
+		local_irq_save_nort(flags);
 		lock_tx_qs(priv);
 		lock_rx_qs(priv);
 
@@ -509,7 +509,7 @@ static int gfar_sringparam(struct net_device *dev,
 
 		unlock_rx_qs(priv);
 		unlock_tx_qs(priv);
-		local_irq_restore(flags);
+		local_irq_restore_nort(flags);
 
 		for (i = 0; i < priv->num_rx_queues; i++)
 			gfar_clean_rx_ring(priv->rx_queue[i],
@@ -624,7 +624,7 @@ int gfar_set_features(struct net_device *dev, netdev_features_t features)
 		/* Halt TX and RX, and process the frames which
 		 * have already been received
 		 */
-		local_irq_save(flags);
+		local_irq_save_nort(flags);
 		lock_tx_qs(priv);
 		lock_rx_qs(priv);
 
@@ -632,7 +632,7 @@ int gfar_set_features(struct net_device *dev, netdev_features_t features)
 
 		unlock_tx_qs(priv);
 		unlock_rx_qs(priv);
-		local_irq_restore(flags);
+		local_irq_restore_nort(flags);
 
 		for (i = 0; i < priv->num_rx_queues; i++)
 			gfar_clean_rx_ring(priv->rx_queue[i],
diff --git a/drivers/net/ethernet/freescale/gianfar_sysfs.c b/drivers/net/ethernet/freescale/gianfar_sysfs.c
index acb55af..f0160e67 100644
--- a/drivers/net/ethernet/freescale/gianfar_sysfs.c
+++ b/drivers/net/ethernet/freescale/gianfar_sysfs.c
@@ -68,7 +68,7 @@ static ssize_t gfar_set_bd_stash(struct device *dev,
 		return count;
 
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_rx_qs(priv);
 
 	/* Set the new stashing value */
@@ -84,7 +84,7 @@ static ssize_t gfar_set_bd_stash(struct device *dev,
 	gfar_write(&regs->attr, temp);
 
 	unlock_rx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	return count;
 }
@@ -112,7 +112,7 @@ static ssize_t gfar_set_rx_stash_size(struct device *dev,
 	if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_BUF_STASHING))
 		return count;
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_rx_qs(priv);
 
 	if (length > priv->rx_buffer_size)
@@ -140,7 +140,7 @@ static ssize_t gfar_set_rx_stash_size(struct device *dev,
 
 out:
 	unlock_rx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	return count;
 }
@@ -171,7 +171,7 @@ static ssize_t gfar_set_rx_stash_index(struct device *dev,
 	if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_BUF_STASHING))
 		return count;
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_rx_qs(priv);
 
 	if (index > priv->rx_stash_size)
@@ -189,7 +189,7 @@ static ssize_t gfar_set_rx_stash_index(struct device *dev,
 
 out:
 	unlock_rx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	return count;
 }
@@ -219,7 +219,7 @@ static ssize_t gfar_set_fifo_threshold(struct device *dev,
 	if (length > GFAR_MAX_FIFO_THRESHOLD)
 		return count;
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_tx_qs(priv);
 
 	priv->fifo_threshold = length;
@@ -230,7 +230,7 @@ static ssize_t gfar_set_fifo_threshold(struct device *dev,
 	gfar_write(&regs->fifo_tx_thr, temp);
 
 	unlock_tx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	return count;
 }
@@ -259,7 +259,7 @@ static ssize_t gfar_set_fifo_starve(struct device *dev,
 	if (num > GFAR_MAX_FIFO_STARVE)
 		return count;
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_tx_qs(priv);
 
 	priv->fifo_starve = num;
@@ -270,7 +270,7 @@ static ssize_t gfar_set_fifo_starve(struct device *dev,
 	gfar_write(&regs->fifo_tx_starve, temp);
 
 	unlock_tx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	return count;
 }
@@ -300,7 +300,7 @@ static ssize_t gfar_set_fifo_starve_off(struct device *dev,
 	if (num > GFAR_MAX_FIFO_STARVE_OFF)
 		return count;
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	lock_tx_qs(priv);
 
 	priv->fifo_starve_off = num;
@@ -311,7 +311,7 @@ static ssize_t gfar_set_fifo_starve_off(struct device *dev,
 	gfar_write(&regs->fifo_tx_starve_shutoff, temp);
 
 	unlock_tx_qs(priv);
-	local_irq_restore(flags);
+	local_irq_restore_nort(flags);
 
 	return count;
 }
-- 
1.9.1

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