From: Robert Hancock robert.hancock@calian.com
[ Upstream commit cb45a8bf4693965e89d115cd2c510f12bc127c37 ]
The RX and TX byte/packet statistics in this driver could be overflowed relatively quickly on a 32-bit platform. Switch these stats to use the u64_stats infrastructure to avoid this.
Signed-off-by: Robert Hancock robert.hancock@calian.com Link: https://lore.kernel.org/r/20220829233901.3429419-1-robert.hancock@calian.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/xilinx/xilinx_axienet.h | 12 ++++++ .../net/ethernet/xilinx/xilinx_axienet_main.c | 37 +++++++++++++++++-- 2 files changed, 45 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h b/drivers/net/ethernet/xilinx/xilinx_axienet.h index f2e2261b4b7d..8ff4333de2ad 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet.h +++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h @@ -402,6 +402,9 @@ struct axidma_bd { * @rx_bd_num: Size of RX buffer descriptor ring * @rx_bd_ci: Stores the index of the Rx buffer descriptor in the ring being * accessed currently. + * @rx_packets: RX packet count for statistics + * @rx_bytes: RX byte count for statistics + * @rx_stat_sync: Synchronization object for RX stats * @napi_tx: NAPI TX control structure * @tx_dma_cr: Nominal content of TX DMA control register * @tx_bd_v: Virtual address of the TX buffer descriptor ring @@ -411,6 +414,9 @@ struct axidma_bd { * complete. Only updated at runtime by TX NAPI poll. * @tx_bd_tail: Stores the index of the next Tx buffer descriptor in the ring * to be populated. + * @tx_packets: TX packet count for statistics + * @tx_bytes: TX byte count for statistics + * @tx_stat_sync: Synchronization object for TX stats * @dma_err_task: Work structure to process Axi DMA errors * @tx_irq: Axidma TX IRQ number * @rx_irq: Axidma RX IRQ number @@ -458,6 +464,9 @@ struct axienet_local { dma_addr_t rx_bd_p; u32 rx_bd_num; u32 rx_bd_ci; + u64_stats_t rx_packets; + u64_stats_t rx_bytes; + struct u64_stats_sync rx_stat_sync;
struct napi_struct napi_tx; u32 tx_dma_cr; @@ -466,6 +475,9 @@ struct axienet_local { u32 tx_bd_num; u32 tx_bd_ci; u32 tx_bd_tail; + u64_stats_t tx_packets; + u64_stats_t tx_bytes; + struct u64_stats_sync tx_stat_sync;
struct work_struct dma_err_task;
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index 1760930ec0c4..9262988d26a3 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -752,8 +752,10 @@ static int axienet_tx_poll(struct napi_struct *napi, int budget) if (lp->tx_bd_ci >= lp->tx_bd_num) lp->tx_bd_ci %= lp->tx_bd_num;
- ndev->stats.tx_packets += packets; - ndev->stats.tx_bytes += size; + u64_stats_update_begin(&lp->tx_stat_sync); + u64_stats_add(&lp->tx_packets, packets); + u64_stats_add(&lp->tx_bytes, size); + u64_stats_update_end(&lp->tx_stat_sync);
/* Matches barrier in axienet_start_xmit */ smp_mb(); @@ -984,8 +986,10 @@ static int axienet_rx_poll(struct napi_struct *napi, int budget) cur_p = &lp->rx_bd_v[lp->rx_bd_ci]; }
- lp->ndev->stats.rx_packets += packets; - lp->ndev->stats.rx_bytes += size; + u64_stats_update_begin(&lp->rx_stat_sync); + u64_stats_add(&lp->rx_packets, packets); + u64_stats_add(&lp->rx_bytes, size); + u64_stats_update_end(&lp->rx_stat_sync);
if (tail_p) axienet_dma_out_addr(lp, XAXIDMA_RX_TDESC_OFFSET, tail_p); @@ -1292,10 +1296,32 @@ static int axienet_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) return phylink_mii_ioctl(lp->phylink, rq, cmd); }
+static void +axienet_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) +{ + struct axienet_local *lp = netdev_priv(dev); + unsigned int start; + + netdev_stats_to_stats64(stats, &dev->stats); + + do { + start = u64_stats_fetch_begin_irq(&lp->rx_stat_sync); + stats->rx_packets = u64_stats_read(&lp->rx_packets); + stats->rx_bytes = u64_stats_read(&lp->rx_bytes); + } while (u64_stats_fetch_retry_irq(&lp->rx_stat_sync, start)); + + do { + start = u64_stats_fetch_begin_irq(&lp->tx_stat_sync); + stats->tx_packets = u64_stats_read(&lp->tx_packets); + stats->tx_bytes = u64_stats_read(&lp->tx_bytes); + } while (u64_stats_fetch_retry_irq(&lp->tx_stat_sync, start)); +} + static const struct net_device_ops axienet_netdev_ops = { .ndo_open = axienet_open, .ndo_stop = axienet_stop, .ndo_start_xmit = axienet_start_xmit, + .ndo_get_stats64 = axienet_get_stats64, .ndo_change_mtu = axienet_change_mtu, .ndo_set_mac_address = netdev_set_mac_address, .ndo_validate_addr = eth_validate_addr, @@ -1850,6 +1876,9 @@ static int axienet_probe(struct platform_device *pdev) lp->rx_bd_num = RX_BD_NUM_DEFAULT; lp->tx_bd_num = TX_BD_NUM_DEFAULT;
+ u64_stats_init(&lp->rx_stat_sync); + u64_stats_init(&lp->tx_stat_sync); + netif_napi_add(ndev, &lp->napi_rx, axienet_rx_poll, NAPI_POLL_WEIGHT); netif_napi_add(ndev, &lp->napi_tx, axienet_tx_poll, NAPI_POLL_WEIGHT);