This is a note to let you know that I've just added the patch titled net: hns3: default enable tx bounce buffer when smmu enabled to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-hns3-default-enable-tx-bounce-buffer-when-smmu-e.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ceb0ea1cbece9d1be93ef301b5c5dc69ea3f26cc Author: Peiyang Wang <wangpeiyang1@xxxxxxxxxx> Date: Fri Oct 25 17:29:30 2024 +0800 net: hns3: default enable tx bounce buffer when smmu enabled [ Upstream commit e6ab19443b36a45ebfb392775cb17d6a78dd07ea ] The SMMU engine on HIP09 chip has a hardware issue. SMMU pagetable prefetch features may prefetch and use a invalid PTE even the PTE is valid at that time. This will cause the device trigger fake pagefaults. The solution is to avoid prefetching by adding a SYNC command when smmu mapping a iova. But the performance of nic has a sharp drop. Then we do this workaround, always enable tx bounce buffer, avoid mapping/unmapping on TX path. This issue only affects HNS3, so we always enable tx bounce buffer when smmu enabled to improve performance. Fixes: 295ba232a8c3 ("net: hns3: add device version to replace pci revision") Signed-off-by: Peiyang Wang <wangpeiyang1@xxxxxxxxxx> Signed-off-by: Jian Shen <shenjian15@xxxxxxxxxx> Signed-off-by: Jijie Shao <shaojijie@xxxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c index 14d086b535a2d..1f9bbf13214fb 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -11,6 +11,7 @@ #include <linux/irq.h> #include <linux/ip.h> #include <linux/ipv6.h> +#include <linux/iommu.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/skbuff.h> @@ -1032,6 +1033,8 @@ static bool hns3_can_use_tx_sgl(struct hns3_enet_ring *ring, static void hns3_init_tx_spare_buffer(struct hns3_enet_ring *ring) { u32 alloc_size = ring->tqp->handle->kinfo.tx_spare_buf_size; + struct net_device *netdev = ring_to_netdev(ring); + struct hns3_nic_priv *priv = netdev_priv(netdev); struct hns3_tx_spare *tx_spare; struct page *page; dma_addr_t dma; @@ -1073,6 +1076,7 @@ static void hns3_init_tx_spare_buffer(struct hns3_enet_ring *ring) tx_spare->buf = page_address(page); tx_spare->len = PAGE_SIZE << order; ring->tx_spare = tx_spare; + ring->tx_copybreak = priv->tx_copybreak; return; dma_mapping_error: @@ -4872,6 +4876,30 @@ static void hns3_nic_dealloc_vector_data(struct hns3_nic_priv *priv) devm_kfree(&pdev->dev, priv->tqp_vector); } +static void hns3_update_tx_spare_buf_config(struct hns3_nic_priv *priv) +{ +#define HNS3_MIN_SPARE_BUF_SIZE (2 * 1024 * 1024) +#define HNS3_MAX_PACKET_SIZE (64 * 1024) + + struct iommu_domain *domain = iommu_get_domain_for_dev(priv->dev); + struct hnae3_ae_dev *ae_dev = hns3_get_ae_dev(priv->ae_handle); + struct hnae3_handle *handle = priv->ae_handle; + + if (ae_dev->dev_version < HNAE3_DEVICE_VERSION_V3) + return; + + if (!(domain && iommu_is_dma_domain(domain))) + return; + + priv->min_tx_copybreak = HNS3_MAX_PACKET_SIZE; + priv->min_tx_spare_buf_size = HNS3_MIN_SPARE_BUF_SIZE; + + if (priv->tx_copybreak < priv->min_tx_copybreak) + priv->tx_copybreak = priv->min_tx_copybreak; + if (handle->kinfo.tx_spare_buf_size < priv->min_tx_spare_buf_size) + handle->kinfo.tx_spare_buf_size = priv->min_tx_spare_buf_size; +} + static void hns3_ring_get_cfg(struct hnae3_queue *q, struct hns3_nic_priv *priv, unsigned int ring_type) { @@ -5106,6 +5134,7 @@ int hns3_init_all_ring(struct hns3_nic_priv *priv) int i, j; int ret; + hns3_update_tx_spare_buf_config(priv); for (i = 0; i < ring_num; i++) { ret = hns3_alloc_ring_memory(&priv->ring[i]); if (ret) { @@ -5310,6 +5339,8 @@ static int hns3_client_init(struct hnae3_handle *handle) priv->ae_handle = handle; priv->tx_timeout_count = 0; priv->max_non_tso_bd_num = ae_dev->dev_specs.max_non_tso_bd_num; + priv->min_tx_copybreak = 0; + priv->min_tx_spare_buf_size = 0; set_bit(HNS3_NIC_STATE_DOWN, &priv->state); handle->msg_enable = netif_msg_init(debug, DEFAULT_MSG_LEVEL); diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h index d36c4ed16d8dd..caf7a4df85852 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h @@ -596,6 +596,8 @@ struct hns3_nic_priv { struct hns3_enet_coalesce rx_coal; u32 tx_copybreak; u32 rx_copybreak; + u32 min_tx_copybreak; + u32 min_tx_spare_buf_size; }; union l3_hdr_info { diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c index 78181eea93c1c..e03ba5aa3d182 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c @@ -1928,6 +1928,31 @@ static int hns3_set_tx_spare_buf_size(struct net_device *netdev, return ret; } +static int hns3_check_tx_copybreak(struct net_device *netdev, u32 copybreak) +{ + struct hns3_nic_priv *priv = netdev_priv(netdev); + + if (copybreak < priv->min_tx_copybreak) { + netdev_err(netdev, "tx copybreak %u should be no less than %u!\n", + copybreak, priv->min_tx_copybreak); + return -EINVAL; + } + return 0; +} + +static int hns3_check_tx_spare_buf_size(struct net_device *netdev, u32 buf_size) +{ + struct hns3_nic_priv *priv = netdev_priv(netdev); + + if (buf_size < priv->min_tx_spare_buf_size) { + netdev_err(netdev, + "tx spare buf size %u should be no less than %u!\n", + buf_size, priv->min_tx_spare_buf_size); + return -EINVAL; + } + return 0; +} + static int hns3_set_tunable(struct net_device *netdev, const struct ethtool_tunable *tuna, const void *data) @@ -1944,6 +1969,10 @@ static int hns3_set_tunable(struct net_device *netdev, switch (tuna->id) { case ETHTOOL_TX_COPYBREAK: + ret = hns3_check_tx_copybreak(netdev, *(u32 *)data); + if (ret) + return ret; + priv->tx_copybreak = *(u32 *)data; for (i = 0; i < h->kinfo.num_tqps; i++) @@ -1958,6 +1987,10 @@ static int hns3_set_tunable(struct net_device *netdev, break; case ETHTOOL_TX_COPYBREAK_BUF_SIZE: + ret = hns3_check_tx_spare_buf_size(netdev, *(u32 *)data); + if (ret) + return ret; + old_tx_spare_buf_size = h->kinfo.tx_spare_buf_size; new_tx_spare_buf_size = *(u32 *)data; netdev_info(netdev, "request to set tx spare buf size from %u to %u\n",