Commit 12889ce9 authored by Moon Yeounsu's avatar Moon Yeounsu Committed by Jakub Kicinski
Browse files

net: dlink: add synchronization for stats update 



This patch synchronizes code that accesses from both user-space
and IRQ contexts. The `get_stats()` function can be called from both
context.

`dev->stats.tx_errors` and `dev->stats.collisions` are also updated
in the `tx_errors()` function. Therefore, these fields must also be
protected by synchronized.

There is no code that accessses `dev->stats.tx_errors` between the
previous and updated lines, so the updating point can be moved.

Signed-off-by: default avatarMoon Yeounsu <yyyynoom@gmail.com>
Link: https://patch.msgid.link/20250515075333.48290-1-yyyynoom@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent b66b76a8

drivers/net/ethernet/dlink/dl2k.c

+13 −1
Original line number Diff line number Diff line
@@ -146,6 +146,8 @@ rio_probe1 (struct pci_dev *pdev, const struct pci_device_id *ent) 
	np->ioaddr = ioaddr;

	np->chip_id = chip_idx;

	np->pdev = pdev;



	spin_lock_init(&np->stats_lock);

	spin_lock_init (&np->tx_lock);

	spin_lock_init (&np->rx_lock);
@@ -865,7 +867,6 @@ tx_error (struct net_device *dev, int tx_status) 
	frame_id = (tx_status & 0xffff0000);

	printk (KERN_ERR "%s: Transmit error, TxStatus %4.4x, FrameId %d.\n",

		dev->name, tx_status, frame_id);

	dev->stats.tx_errors++;

	/* Ttransmit Underrun */

	if (tx_status & 0x10) {

		dev->stats.tx_fifo_errors++;
@@ -902,9 +903,15 @@ tx_error (struct net_device *dev, int tx_status) 
		rio_set_led_mode(dev);

		/* Let TxStartThresh stay default value */

	}



	spin_lock(&np->stats_lock);

	/* Maximum Collisions */

	if (tx_status & 0x08)

		dev->stats.collisions++;



	dev->stats.tx_errors++;

	spin_unlock(&np->stats_lock);



	/* Restart the Tx */

	dw32(MACCtrl, dr16(MACCtrl) | TxEnable);

}
@@ -1073,7 +1080,9 @@ get_stats (struct net_device *dev) 
	int i;

#endif

	unsigned int stat_reg;

	unsigned long flags;



	spin_lock_irqsave(&np->stats_lock, flags);

	/* All statistics registers need to be acknowledged,

	   else statistic overflow could cause problems */
@@ -1123,6 +1132,9 @@ get_stats (struct net_device *dev) 
	dr16(TCPCheckSumErrors);

	dr16(UDPCheckSumErrors);

	dr16(IPCheckSumErrors);



	spin_unlock_irqrestore(&np->stats_lock, flags);



	return &dev->stats;

}

drivers/net/ethernet/dlink/dl2k.h

+2 −0
Original line number Diff line number Diff line
@@ -372,6 +372,8 @@ struct netdev_private { 
	struct pci_dev *pdev;

	void __iomem *ioaddr;

	void __iomem *eeprom_addr;

	// To ensure synchronization when stats are updated.

	spinlock_t stats_lock;

	spinlock_t tx_lock;

	spinlock_t rx_lock;

	unsigned int rx_buf_sz;		/* Based on MTU+slack. */