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 <davem@davemloft.net>
---
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 <davem@davemloft.net>
---
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 <davem@davemloft.net>
---
.../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)