From a03bb56e67c357980dae886683733dab5583dc14 Mon Sep 17 00:00:00 2001 From: Govindarajulu Varadarajan <_govind@gmx.com> Date: Wed, 3 Sep 2014 03:17:19 +0530 Subject: [PATCH 1/3] enic: implement rx_copybreak Calling dma_map_single()/dma_unmap_single() is quite expensive compared to copying a small packet. So let's copy short frames and keep the buffers mapped. Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com> Signed-off-by: David S. Miller --- drivers/net/ethernet/cisco/enic/enic.h | 1 + drivers/net/ethernet/cisco/enic/enic_main.c | 50 +++++++++++++++++++-- 2 files changed, 48 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/cisco/enic/enic.h b/drivers/net/ethernet/cisco/enic/enic.h index 962510f391df..5ba5ad071bb6 100644 --- a/drivers/net/ethernet/cisco/enic/enic.h +++ b/drivers/net/ethernet/cisco/enic/enic.h @@ -186,6 +186,7 @@ struct enic { ____cacheline_aligned struct vnic_cq cq[ENIC_CQ_MAX]; unsigned int cq_count; struct enic_rfs_flw_tbl rfs_h; + u32 rx_copybreak; }; static inline struct device *enic_get_dev(struct enic *enic) diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c index c8832bc1c5f7..929bfe70080a 100644 --- a/drivers/net/ethernet/cisco/enic/enic_main.c +++ b/drivers/net/ethernet/cisco/enic/enic_main.c @@ -66,6 +66,8 @@ #define PCI_DEVICE_ID_CISCO_VIC_ENET_DYN 0x0044 /* enet dynamic vnic */ #define PCI_DEVICE_ID_CISCO_VIC_ENET_VF 0x0071 /* enet SRIOV VF */ +#define RX_COPYBREAK_DEFAULT 256 + /* Supported devices */ static const struct pci_device_id enic_id_table[] = { { PCI_VDEVICE(CISCO, PCI_DEVICE_ID_CISCO_VIC_ENET) }, @@ -924,6 +926,7 @@ static void enic_free_rq_buf(struct vnic_rq *rq, struct vnic_rq_buf *buf) pci_unmap_single(enic->pdev, buf->dma_addr, buf->len, PCI_DMA_FROMDEVICE); dev_kfree_skb_any(buf->os_buf); + buf->os_buf = NULL; } static int enic_rq_alloc_buf(struct vnic_rq *rq) @@ -934,7 +937,24 @@ static int enic_rq_alloc_buf(struct vnic_rq *rq) unsigned int len = netdev->mtu + VLAN_ETH_HLEN; unsigned int os_buf_index = 0; dma_addr_t dma_addr; + struct vnic_rq_buf *buf = rq->to_use; + if (buf->os_buf) { + buf = buf->next; + rq->to_use = buf; + rq->ring.desc_avail--; + if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) { + /* Adding write memory barrier prevents compiler and/or + * CPU reordering, thus avoiding descriptor posting + * before descriptor is initialized. Otherwise, hardware + * can read stale descriptor fields. + */ + wmb(); + iowrite32(buf->index, &rq->ctrl->posted_index); + } + + return 0; + } skb = netdev_alloc_skb_ip_align(netdev, len); if (!skb) return -ENOMEM; @@ -957,6 +977,25 @@ static void enic_intr_update_pkt_size(struct vnic_rx_bytes_counter *pkt_size, pkt_size->small_pkt_bytes_cnt += pkt_len; } +static bool enic_rxcopybreak(struct net_device *netdev, struct sk_buff **skb, + struct vnic_rq_buf *buf, u16 len) +{ + struct enic *enic = netdev_priv(netdev); + struct sk_buff *new_skb; + + if (len > enic->rx_copybreak) + return false; + new_skb = netdev_alloc_skb_ip_align(netdev, len); + if (!new_skb) + return false; + pci_dma_sync_single_for_cpu(enic->pdev, buf->dma_addr, len, + DMA_FROM_DEVICE); + memcpy(new_skb->data, (*skb)->data, len); + *skb = new_skb; + + return true; +} + static void enic_rq_indicate_buf(struct vnic_rq *rq, struct cq_desc *cq_desc, struct vnic_rq_buf *buf, int skipped, void *opaque) @@ -978,9 +1017,6 @@ static void enic_rq_indicate_buf(struct vnic_rq *rq, return; skb = buf->os_buf; - prefetch(skb->data - NET_IP_ALIGN); - pci_unmap_single(enic->pdev, buf->dma_addr, - buf->len, PCI_DMA_FROMDEVICE); cq_enet_rq_desc_dec((struct cq_enet_rq_desc *)cq_desc, &type, &color, &q_number, &completed_index, @@ -1011,6 +1047,13 @@ static void enic_rq_indicate_buf(struct vnic_rq *rq, /* Good receive */ + if (!enic_rxcopybreak(netdev, &skb, buf, bytes_written)) { + buf->os_buf = NULL; + pci_unmap_single(enic->pdev, buf->dma_addr, buf->len, + PCI_DMA_FROMDEVICE); + } + prefetch(skb->data - NET_IP_ALIGN); + skb_put(skb, bytes_written); skb->protocol = eth_type_trans(skb, netdev); skb_record_rx_queue(skb, q_number); @@ -2531,6 +2574,7 @@ static int enic_probe(struct pci_dev *pdev, const struct pci_device_id *ent) dev_err(dev, "Cannot register net device, aborting\n"); goto err_out_dev_deinit; } + enic->rx_copybreak = RX_COPYBREAK_DEFAULT; return 0; From f0db9b073415848709dd59a6394969882f517da9 Mon Sep 17 00:00:00 2001 From: Govindarajulu Varadarajan <_govind@gmx.com> Date: Wed, 3 Sep 2014 03:17:20 +0530 Subject: [PATCH 2/3] ethtool: Add generic options for tunables This patch adds new ethtool cmd, ETHTOOL_GTUNABLE & ETHTOOL_STUNABLE for getting tunable values from driver. Add get_tunable and set_tunable to ethtool_ops. Driver implements these functions for getting/setting tunable value. Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com> Signed-off-by: David S. Miller --- include/linux/ethtool.h | 4 ++ include/uapi/linux/ethtool.h | 28 +++++++++++++ net/core/ethtool.c | 81 ++++++++++++++++++++++++++++++++++++ 3 files changed, 113 insertions(+) diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index e658229fee39..c1a2d60dfb82 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -257,6 +257,10 @@ struct ethtool_ops { struct ethtool_eeprom *, u8 *); int (*get_eee)(struct net_device *, struct ethtool_eee *); int (*set_eee)(struct net_device *, struct ethtool_eee *); + int (*get_tunable)(struct net_device *, + const struct ethtool_tunable *, void *); + int (*set_tunable)(struct net_device *, + const struct ethtool_tunable *, const void *); }; diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index e3c7a719c76b..7a364f2f3d3f 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h @@ -209,6 +209,32 @@ struct ethtool_value { __u32 data; }; +enum tunable_id { + ETHTOOL_ID_UNSPEC, + ETHTOOL_RX_COPYBREAK, +}; + +enum tunable_type_id { + ETHTOOL_TUNABLE_UNSPEC, + ETHTOOL_TUNABLE_U8, + ETHTOOL_TUNABLE_U16, + ETHTOOL_TUNABLE_U32, + ETHTOOL_TUNABLE_U64, + ETHTOOL_TUNABLE_STRING, + ETHTOOL_TUNABLE_S8, + ETHTOOL_TUNABLE_S16, + ETHTOOL_TUNABLE_S32, + ETHTOOL_TUNABLE_S64, +}; + +struct ethtool_tunable { + __u32 cmd; + __u32 id; + __u32 type_id; + __u32 len; + void *data[0]; +}; + /** * struct ethtool_regs - hardware register dump * @cmd: Command number = %ETHTOOL_GREGS @@ -1152,6 +1178,8 @@ enum ethtool_sfeatures_retval_bits { #define ETHTOOL_GRSSH 0x00000046 /* Get RX flow hash configuration */ #define ETHTOOL_SRSSH 0x00000047 /* Set RX flow hash configuration */ +#define ETHTOOL_GTUNABLE 0x00000048 /* Get tunable configuration */ +#define ETHTOOL_STUNABLE 0x00000049 /* Set tunable configuration */ /* compatibility with older code */ #define SPARC_ETH_GSET ETHTOOL_GSET diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 17cb912793fa..27e61b886520 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -1621,6 +1621,80 @@ static int ethtool_get_module_eeprom(struct net_device *dev, modinfo.eeprom_len); } +static int ethtool_tunable_valid(const struct ethtool_tunable *tuna) +{ + switch (tuna->id) { + case ETHTOOL_RX_COPYBREAK: + if (tuna->len != sizeof(u32) || + tuna->type_id != ETHTOOL_TUNABLE_U32) + return -EINVAL; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int ethtool_get_tunable(struct net_device *dev, void __user *useraddr) +{ + int ret; + struct ethtool_tunable tuna; + const struct ethtool_ops *ops = dev->ethtool_ops; + void *data; + + if (!ops->get_tunable) + return -EOPNOTSUPP; + if (copy_from_user(&tuna, useraddr, sizeof(tuna))) + return -EFAULT; + ret = ethtool_tunable_valid(&tuna); + if (ret) + return ret; + data = kmalloc(tuna.len, GFP_USER); + if (!data) + return -ENOMEM; + ret = ops->get_tunable(dev, &tuna, data); + if (ret) + goto out; + useraddr += sizeof(tuna); + ret = -EFAULT; + if (copy_to_user(useraddr, data, tuna.len)) + goto out; + ret = 0; + +out: + kfree(data); + return ret; +} + +static int ethtool_set_tunable(struct net_device *dev, void __user *useraddr) +{ + int ret; + struct ethtool_tunable tuna; + const struct ethtool_ops *ops = dev->ethtool_ops; + void *data; + + if (!ops->set_tunable) + return -EOPNOTSUPP; + if (copy_from_user(&tuna, useraddr, sizeof(tuna))) + return -EFAULT; + ret = ethtool_tunable_valid(&tuna); + if (ret) + return ret; + data = kmalloc(tuna.len, GFP_USER); + if (!data) + return -ENOMEM; + useraddr += sizeof(tuna); + ret = -EFAULT; + if (copy_from_user(data, useraddr, tuna.len)) + goto out; + ret = ops->set_tunable(dev, &tuna, data); + +out: + kfree(data); + return ret; +} + /* The main entry point in this file. Called from net/core/dev_ioctl.c */ int dev_ethtool(struct net *net, struct ifreq *ifr) @@ -1670,6 +1744,7 @@ int dev_ethtool(struct net *net, struct ifreq *ifr) case ETHTOOL_GCHANNELS: case ETHTOOL_GET_TS_INFO: case ETHTOOL_GEEE: + case ETHTOOL_GTUNABLE: break; default: if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) @@ -1857,6 +1932,12 @@ int dev_ethtool(struct net *net, struct ifreq *ifr) case ETHTOOL_GMODULEEEPROM: rc = ethtool_get_module_eeprom(dev, useraddr); break; + case ETHTOOL_GTUNABLE: + rc = ethtool_get_tunable(dev, useraddr); + break; + case ETHTOOL_STUNABLE: + rc = ethtool_set_tunable(dev, useraddr); + break; default: rc = -EOPNOTSUPP; } From d4ad30b182305ecf97f145a5d4d1fd9e728c6d01 Mon Sep 17 00:00:00 2001 From: Govindarajulu Varadarajan <_govind@gmx.com> Date: Wed, 3 Sep 2014 03:17:21 +0530 Subject: [PATCH 3/3] enic: Add tunable_ops support for rx_copybreak This patch adds support for setting/getting rx_copybreak using generic ethtool tunable. Defines enic_get_tunable() & enic_set_tunable() to get/set rx_copybreak. As of now, these two function supports only rx_copybreak. Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com> Signed-off-by: David S. Miller --- .../net/ethernet/cisco/enic/enic_ethtool.c | 39 +++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/drivers/net/ethernet/cisco/enic/enic_ethtool.c b/drivers/net/ethernet/cisco/enic/enic_ethtool.c index 523c9ceb04c0..85173d620758 100644 --- a/drivers/net/ethernet/cisco/enic/enic_ethtool.c +++ b/drivers/net/ethernet/cisco/enic/enic_ethtool.c @@ -379,6 +379,43 @@ static int enic_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *cmd, return ret; } +static int enic_get_tunable(struct net_device *dev, + const struct ethtool_tunable *tuna, void *data) +{ + struct enic *enic = netdev_priv(dev); + int ret = 0; + + switch (tuna->id) { + case ETHTOOL_RX_COPYBREAK: + *(u32 *)data = enic->rx_copybreak; + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static int enic_set_tunable(struct net_device *dev, + const struct ethtool_tunable *tuna, + const void *data) +{ + struct enic *enic = netdev_priv(dev); + int ret = 0; + + switch (tuna->id) { + case ETHTOOL_RX_COPYBREAK: + enic->rx_copybreak = *(u32 *)data; + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + static const struct ethtool_ops enic_ethtool_ops = { .get_settings = enic_get_settings, .get_drvinfo = enic_get_drvinfo, @@ -391,6 +428,8 @@ static const struct ethtool_ops enic_ethtool_ops = { .get_coalesce = enic_get_coalesce, .set_coalesce = enic_set_coalesce, .get_rxnfc = enic_get_rxnfc, + .get_tunable = enic_get_tunable, + .set_tunable = enic_set_tunable, }; void enic_set_ethtool_ops(struct net_device *netdev)