| From a974d225fb46b62ac53ed85ae6149f818860bf15 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 15 May 2025 16:53:31 +0900 |
| Subject: net: dlink: add synchronization for stats update |
| |
| From: Moon Yeounsu <yyyynoom@gmail.com> |
| |
| [ Upstream commit 12889ce926e9a9baf6b83d809ba316af539b89e2 ] |
| |
| 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: Moon Yeounsu <yyyynoom@gmail.com> |
| Link: https://patch.msgid.link/20250515075333.48290-1-yyyynoom@gmail.com |
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/net/ethernet/dlink/dl2k.c | 14 +++++++++++++- |
| drivers/net/ethernet/dlink/dl2k.h | 2 ++ |
| 2 files changed, 15 insertions(+), 1 deletion(-) |
| |
| diff --git a/drivers/net/ethernet/dlink/dl2k.c b/drivers/net/ethernet/dlink/dl2k.c |
| index eb23157641343..8d57fb5072054 100644 |
| --- a/drivers/net/ethernet/dlink/dl2k.c |
| +++ b/drivers/net/ethernet/dlink/dl2k.c |
| @@ -155,6 +155,8 @@ 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); |
| |
| @@ -875,7 +877,6 @@ 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++; |
| @@ -912,9 +913,15 @@ 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); |
| } |
| @@ -1084,7 +1091,9 @@ 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 */ |
| |
| @@ -1134,6 +1143,9 @@ get_stats (struct net_device *dev) |
| dr16(TCPCheckSumErrors); |
| dr16(UDPCheckSumErrors); |
| dr16(IPCheckSumErrors); |
| + |
| + spin_unlock_irqrestore(&np->stats_lock, flags); |
| + |
| return &dev->stats; |
| } |
| |
| diff --git a/drivers/net/ethernet/dlink/dl2k.h b/drivers/net/ethernet/dlink/dl2k.h |
| index 0e33e2eaae960..56aff2f0bdbfa 100644 |
| --- a/drivers/net/ethernet/dlink/dl2k.h |
| +++ b/drivers/net/ethernet/dlink/dl2k.h |
| @@ -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. */ |
| -- |
| 2.39.5 |
| |
