net: netsec: add XDP support

The interface only supports 1 Tx queue so locking is introduced on
the Tx queue if XDP is enabled to make sure .ndo_start_xmit and
.ndo_xdp_xmit won't corrupt Tx ring

- Performance (SMMU off)

Benchmark   XDP_SKB     XDP_DRV
xdp1        291kpps     344kpps
rxdrop      282kpps     342kpps

- Performance (SMMU on)
Benchmark   XDP_SKB     XDP_DRV
xdp1        167kpps     324kpps
rxdrop      164kpps     323kpps

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ilias Apalodimas 2019-06-29 08:23:25 +03:00 committed by David S. Miller
parent bb005f2a70
commit ba2b232108

View File

@ -9,6 +9,9 @@
#include <linux/etherdevice.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/netlink.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <net/tcp.h>
#include <net/page_pool.h>
@ -236,23 +239,41 @@
#define DESC_NUM 256
#define NETSEC_SKB_PAD (NET_SKB_PAD + NET_IP_ALIGN)
#define NETSEC_RX_BUF_NON_DATA (NETSEC_SKB_PAD + \
#define NETSEC_RXBUF_HEADROOM (max(XDP_PACKET_HEADROOM, NET_SKB_PAD) + \
NET_IP_ALIGN)
#define NETSEC_RX_BUF_NON_DATA (NETSEC_RXBUF_HEADROOM + \
SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
#define DESC_SZ sizeof(struct netsec_de)
#define NETSEC_F_NETSEC_VER_MAJOR_NUM(x) ((x) & 0xffff0000)
#define NETSEC_XDP_PASS 0
#define NETSEC_XDP_CONSUMED BIT(0)
#define NETSEC_XDP_TX BIT(1)
#define NETSEC_XDP_REDIR BIT(2)
#define NETSEC_XDP_RX_OK (NETSEC_XDP_PASS | NETSEC_XDP_TX | NETSEC_XDP_REDIR)
enum ring_id {
NETSEC_RING_TX = 0,
NETSEC_RING_RX
};
enum buf_type {
TYPE_NETSEC_SKB = 0,
TYPE_NETSEC_XDP_TX,
TYPE_NETSEC_XDP_NDO,
};
struct netsec_desc {
struct sk_buff *skb;
union {
struct sk_buff *skb;
struct xdp_frame *xdpf;
};
dma_addr_t dma_addr;
void *addr;
u16 len;
u8 buf_type;
};
struct netsec_desc_ring {
@ -260,13 +281,17 @@ struct netsec_desc_ring {
struct netsec_desc *desc;
void *vaddr;
u16 head, tail;
u16 xdp_xmit; /* netsec_xdp_xmit packets */
bool is_xdp;
struct page_pool *page_pool;
struct xdp_rxq_info xdp_rxq;
spinlock_t lock; /* XDP tx queue locking */
};
struct netsec_priv {
struct netsec_desc_ring desc_ring[NETSEC_RING_MAX];
struct ethtool_coalesce et_coalesce;
struct bpf_prog *xdp_prog;
spinlock_t reglock; /* protect reg access */
struct napi_struct napi;
phy_interface_t phy_interface;
@ -303,6 +328,11 @@ struct netsec_rx_pkt_info {
bool err_flag;
};
static void netsec_set_tx_de(struct netsec_priv *priv,
struct netsec_desc_ring *dring,
const struct netsec_tx_pkt_ctrl *tx_ctrl,
const struct netsec_desc *desc, void *buf);
static void netsec_write(struct netsec_priv *priv, u32 reg_addr, u32 val)
{
writel(val, priv->ioaddr + reg_addr);
@ -609,6 +639,9 @@ static bool netsec_clean_tx_dring(struct netsec_priv *priv)
int tail = dring->tail;
int cnt = 0;
if (dring->is_xdp)
spin_lock(&dring->lock);
pkts = 0;
bytes = 0;
entry = dring->vaddr + DESC_SZ * tail;
@ -622,13 +655,23 @@ static bool netsec_clean_tx_dring(struct netsec_priv *priv)
eop = (entry->attr >> NETSEC_TX_LAST) & 1;
dma_rmb();
dma_unmap_single(priv->dev, desc->dma_addr, desc->len,
DMA_TO_DEVICE);
if (eop) {
pkts++;
if (desc->buf_type == TYPE_NETSEC_SKB)
dma_unmap_single(priv->dev, desc->dma_addr, desc->len,
DMA_TO_DEVICE);
else if (desc->buf_type == TYPE_NETSEC_XDP_NDO)
dma_unmap_single(priv->dev, desc->dma_addr,
desc->len, DMA_TO_DEVICE);
if (!eop)
goto next;
if (desc->buf_type == TYPE_NETSEC_SKB) {
bytes += desc->skb->len;
dev_kfree_skb(desc->skb);
} else {
xdp_return_frame(desc->xdpf);
}
next:
/* clean up so netsec_uninit_pkt_dring() won't free the skb
* again
*/
@ -645,6 +688,8 @@ static bool netsec_clean_tx_dring(struct netsec_priv *priv)
entry = dring->vaddr + DESC_SZ * tail;
cnt++;
}
if (dring->is_xdp)
spin_unlock(&dring->lock);
if (!cnt)
return false;
@ -688,12 +733,13 @@ static void *netsec_alloc_rx_data(struct netsec_priv *priv,
if (!page)
return NULL;
/* page_pool API will map the whole page, skip
* NET_SKB_PAD + NET_IP_ALIGN for the payload
/* We allocate the same buffer length for XDP and non-XDP cases.
* page_pool API will map the whole page, skip what's needed for
* network payloads and/or XDP
*/
*dma_handle = page_pool_get_dma_addr(page) + NETSEC_SKB_PAD;
/* make sure the incoming payload fits in the page with the needed
* NET_SKB_PAD + NET_IP_ALIGN + skb_shared_info
*dma_handle = page_pool_get_dma_addr(page) + NETSEC_RXBUF_HEADROOM;
/* Make sure the incoming payload fits in the page for XDP and non-XDP
* cases and reserve enough space for headroom + skb_shared_info
*/
*desc_len = PAGE_SIZE - NETSEC_RX_BUF_NON_DATA;
@ -714,21 +760,159 @@ static void netsec_rx_fill(struct netsec_priv *priv, u16 from, u16 num)
}
}
static void netsec_xdp_ring_tx_db(struct netsec_priv *priv, u16 pkts)
{
if (likely(pkts))
netsec_write(priv, NETSEC_REG_NRM_TX_PKTCNT, pkts);
}
static void netsec_finalize_xdp_rx(struct netsec_priv *priv, u32 xdp_res,
u16 pkts)
{
if (xdp_res & NETSEC_XDP_REDIR)
xdp_do_flush_map();
if (xdp_res & NETSEC_XDP_TX)
netsec_xdp_ring_tx_db(priv, pkts);
}
/* The current driver only supports 1 Txq, this should run under spin_lock() */
static u32 netsec_xdp_queue_one(struct netsec_priv *priv,
struct xdp_frame *xdpf, bool is_ndo)
{
struct netsec_desc_ring *tx_ring = &priv->desc_ring[NETSEC_RING_TX];
struct page *page = virt_to_page(xdpf->data);
struct netsec_tx_pkt_ctrl tx_ctrl = {};
struct netsec_desc tx_desc;
dma_addr_t dma_handle;
u16 filled;
if (tx_ring->head >= tx_ring->tail)
filled = tx_ring->head - tx_ring->tail;
else
filled = tx_ring->head + DESC_NUM - tx_ring->tail;
if (DESC_NUM - filled <= 1)
return NETSEC_XDP_CONSUMED;
if (is_ndo) {
/* this is for ndo_xdp_xmit, the buffer needs mapping before
* sending
*/
dma_handle = dma_map_single(priv->dev, xdpf->data, xdpf->len,
DMA_TO_DEVICE);
if (dma_mapping_error(priv->dev, dma_handle))
return NETSEC_XDP_CONSUMED;
tx_desc.buf_type = TYPE_NETSEC_XDP_NDO;
} else {
/* This is the device Rx buffer from page_pool. No need to remap
* just sync and send it
*/
struct netsec_desc_ring *rx_ring =
&priv->desc_ring[NETSEC_RING_RX];
enum dma_data_direction dma_dir =
page_pool_get_dma_dir(rx_ring->page_pool);
dma_handle = page_pool_get_dma_addr(page) +
NETSEC_RXBUF_HEADROOM;
dma_sync_single_for_device(priv->dev, dma_handle, xdpf->len,
dma_dir);
tx_desc.buf_type = TYPE_NETSEC_XDP_TX;
}
tx_desc.dma_addr = dma_handle;
tx_desc.addr = xdpf->data;
tx_desc.len = xdpf->len;
netsec_set_tx_de(priv, tx_ring, &tx_ctrl, &tx_desc, xdpf);
return NETSEC_XDP_TX;
}
static u32 netsec_xdp_xmit_back(struct netsec_priv *priv, struct xdp_buff *xdp)
{
struct netsec_desc_ring *tx_ring = &priv->desc_ring[NETSEC_RING_TX];
struct xdp_frame *xdpf = convert_to_xdp_frame(xdp);
u32 ret;
if (unlikely(!xdpf))
return NETSEC_XDP_CONSUMED;
spin_lock(&tx_ring->lock);
ret = netsec_xdp_queue_one(priv, xdpf, false);
spin_unlock(&tx_ring->lock);
return ret;
}
static u32 netsec_run_xdp(struct netsec_priv *priv, struct bpf_prog *prog,
struct xdp_buff *xdp)
{
u32 ret = NETSEC_XDP_PASS;
int err;
u32 act;
act = bpf_prog_run_xdp(prog, xdp);
switch (act) {
case XDP_PASS:
ret = NETSEC_XDP_PASS;
break;
case XDP_TX:
ret = netsec_xdp_xmit_back(priv, xdp);
if (ret != NETSEC_XDP_TX)
xdp_return_buff(xdp);
break;
case XDP_REDIRECT:
err = xdp_do_redirect(priv->ndev, xdp, prog);
if (!err) {
ret = NETSEC_XDP_REDIR;
} else {
ret = NETSEC_XDP_CONSUMED;
xdp_return_buff(xdp);
}
break;
default:
bpf_warn_invalid_xdp_action(act);
/* fall through */
case XDP_ABORTED:
trace_xdp_exception(priv->ndev, prog, act);
/* fall through -- handle aborts by dropping packet */
case XDP_DROP:
ret = NETSEC_XDP_CONSUMED;
xdp_return_buff(xdp);
break;
}
return ret;
}
static int netsec_process_rx(struct netsec_priv *priv, int budget)
{
struct netsec_desc_ring *dring = &priv->desc_ring[NETSEC_RING_RX];
struct net_device *ndev = priv->ndev;
struct netsec_rx_pkt_info rx_info;
struct sk_buff *skb;
enum dma_data_direction dma_dir;
struct bpf_prog *xdp_prog;
struct sk_buff *skb = NULL;
u16 xdp_xmit = 0;
u32 xdp_act = 0;
int done = 0;
rcu_read_lock();
xdp_prog = READ_ONCE(priv->xdp_prog);
dma_dir = page_pool_get_dma_dir(dring->page_pool);
while (done < budget) {
u16 idx = dring->tail;
struct netsec_de *de = dring->vaddr + (DESC_SZ * idx);
struct netsec_desc *desc = &dring->desc[idx];
struct page *page = virt_to_page(desc->addr);
u32 xdp_result = XDP_PASS;
u16 pkt_len, desc_len;
dma_addr_t dma_handle;
struct xdp_buff xdp;
void *buf_addr;
if (de->attr & (1U << NETSEC_RX_PKT_OWN_FIELD)) {
@ -770,10 +954,26 @@ static int netsec_process_rx(struct netsec_priv *priv, int budget)
break;
dma_sync_single_for_cpu(priv->dev, desc->dma_addr, pkt_len,
DMA_FROM_DEVICE);
dma_dir);
prefetch(desc->addr);
xdp.data_hard_start = desc->addr;
xdp.data = desc->addr + NETSEC_RXBUF_HEADROOM;
xdp_set_data_meta_invalid(&xdp);
xdp.data_end = xdp.data + pkt_len;
xdp.rxq = &dring->xdp_rxq;
if (xdp_prog) {
xdp_result = netsec_run_xdp(priv, xdp_prog, &xdp);
if (xdp_result != NETSEC_XDP_PASS) {
xdp_act |= xdp_result;
if (xdp_result == NETSEC_XDP_TX)
xdp_xmit++;
goto next;
}
}
skb = build_skb(desc->addr, desc->len + NETSEC_RX_BUF_NON_DATA);
if (unlikely(!skb)) {
/* If skb fails recycle_direct will either unmap and
* free the page or refill the cache depending on the
@ -787,27 +987,32 @@ static int netsec_process_rx(struct netsec_priv *priv, int budget)
}
page_pool_release_page(dring->page_pool, page);
/* Update the descriptor with the new buffer we allocated */
desc->len = desc_len;
desc->dma_addr = dma_handle;
desc->addr = buf_addr;
skb_reserve(skb, NETSEC_SKB_PAD);
skb_put(skb, pkt_len);
skb_reserve(skb, xdp.data - xdp.data_hard_start);
skb_put(skb, xdp.data_end - xdp.data);
skb->protocol = eth_type_trans(skb, priv->ndev);
if (priv->rx_cksum_offload_flag &&
rx_info.rx_cksum_result == NETSEC_RX_CKSUM_OK)
skb->ip_summed = CHECKSUM_UNNECESSARY;
if (napi_gro_receive(&priv->napi, skb) != GRO_DROP) {
next:
if ((skb && napi_gro_receive(&priv->napi, skb) != GRO_DROP) ||
xdp_result & NETSEC_XDP_RX_OK) {
ndev->stats.rx_packets++;
ndev->stats.rx_bytes += pkt_len;
ndev->stats.rx_bytes += xdp.data_end - xdp.data;
}
/* Update the descriptor with fresh buffers */
desc->len = desc_len;
desc->dma_addr = dma_handle;
desc->addr = buf_addr;
netsec_rx_fill(priv, idx, 1);
dring->tail = (dring->tail + 1) % DESC_NUM;
}
netsec_finalize_xdp_rx(priv, xdp_act, xdp_xmit);
rcu_read_unlock();
return done;
}
@ -837,8 +1042,7 @@ static int netsec_napi_poll(struct napi_struct *napi, int budget)
static void netsec_set_tx_de(struct netsec_priv *priv,
struct netsec_desc_ring *dring,
const struct netsec_tx_pkt_ctrl *tx_ctrl,
const struct netsec_desc *desc,
struct sk_buff *skb)
const struct netsec_desc *desc, void *buf)
{
int idx = dring->head;
struct netsec_de *de;
@ -861,10 +1065,16 @@ static void netsec_set_tx_de(struct netsec_priv *priv,
de->data_buf_addr_lw = lower_32_bits(desc->dma_addr);
de->buf_len_info = (tx_ctrl->tcp_seg_len << 16) | desc->len;
de->attr = attr;
dma_wmb();
/* under spin_lock if using XDP */
if (!dring->is_xdp)
dma_wmb();
dring->desc[idx] = *desc;
dring->desc[idx].skb = skb;
if (desc->buf_type == TYPE_NETSEC_SKB)
dring->desc[idx].skb = buf;
else if (desc->buf_type == TYPE_NETSEC_XDP_TX ||
desc->buf_type == TYPE_NETSEC_XDP_NDO)
dring->desc[idx].xdpf = buf;
/* move head ahead */
dring->head = (dring->head + 1) % DESC_NUM;
@ -915,8 +1125,12 @@ static netdev_tx_t netsec_netdev_start_xmit(struct sk_buff *skb,
u16 tso_seg_len = 0;
int filled;
if (dring->is_xdp)
spin_lock_bh(&dring->lock);
filled = netsec_desc_used(dring);
if (netsec_check_stop_tx(priv, filled)) {
if (dring->is_xdp)
spin_unlock_bh(&dring->lock);
net_warn_ratelimited("%s %s Tx queue full\n",
dev_name(priv->dev), ndev->name);
return NETDEV_TX_BUSY;
@ -949,6 +1163,8 @@ static netdev_tx_t netsec_netdev_start_xmit(struct sk_buff *skb,
tx_desc.dma_addr = dma_map_single(priv->dev, skb->data,
skb_headlen(skb), DMA_TO_DEVICE);
if (dma_mapping_error(priv->dev, tx_desc.dma_addr)) {
if (dring->is_xdp)
spin_unlock_bh(&dring->lock);
netif_err(priv, drv, priv->ndev,
"%s: DMA mapping failed\n", __func__);
ndev->stats.tx_dropped++;
@ -957,11 +1173,14 @@ static netdev_tx_t netsec_netdev_start_xmit(struct sk_buff *skb,
}
tx_desc.addr = skb->data;
tx_desc.len = skb_headlen(skb);
tx_desc.buf_type = TYPE_NETSEC_SKB;
skb_tx_timestamp(skb);
netdev_sent_queue(priv->ndev, skb->len);
netsec_set_tx_de(priv, dring, &tx_ctrl, &tx_desc, skb);
if (dring->is_xdp)
spin_unlock_bh(&dring->lock);
netsec_write(priv, NETSEC_REG_NRM_TX_PKTCNT, 1); /* submit another tx */
return NETDEV_TX_OK;
@ -1049,6 +1268,7 @@ err:
static void netsec_setup_tx_dring(struct netsec_priv *priv)
{
struct netsec_desc_ring *dring = &priv->desc_ring[NETSEC_RING_TX];
struct bpf_prog *xdp_prog = READ_ONCE(priv->xdp_prog);
int i;
for (i = 0; i < DESC_NUM; i++) {
@ -1061,11 +1281,18 @@ static void netsec_setup_tx_dring(struct netsec_priv *priv)
*/
de->attr = 1U << NETSEC_TX_SHIFT_OWN_FIELD;
}
if (xdp_prog)
dring->is_xdp = true;
else
dring->is_xdp = false;
}
static int netsec_setup_rx_dring(struct netsec_priv *priv)
{
struct netsec_desc_ring *dring = &priv->desc_ring[NETSEC_RING_RX];
struct bpf_prog *xdp_prog = READ_ONCE(priv->xdp_prog);
struct page_pool_params pp_params = { 0 };
int i, err;
@ -1075,7 +1302,7 @@ static int netsec_setup_rx_dring(struct netsec_priv *priv)
pp_params.pool_size = DESC_NUM;
pp_params.nid = cpu_to_node(0);
pp_params.dev = priv->dev;
pp_params.dma_dir = DMA_FROM_DEVICE;
pp_params.dma_dir = xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
dring->page_pool = page_pool_create(&pp_params);
if (IS_ERR(dring->page_pool)) {
@ -1495,6 +1722,9 @@ static int netsec_netdev_init(struct net_device *ndev)
if (ret)
goto err2;
spin_lock_init(&priv->desc_ring[NETSEC_RING_TX].lock);
spin_lock_init(&priv->desc_ring[NETSEC_RING_RX].lock);
return 0;
err2:
netsec_free_dring(priv, NETSEC_RING_RX);
@ -1527,6 +1757,81 @@ static int netsec_netdev_ioctl(struct net_device *ndev, struct ifreq *ifr,
return phy_mii_ioctl(ndev->phydev, ifr, cmd);
}
static int netsec_xdp_xmit(struct net_device *ndev, int n,
struct xdp_frame **frames, u32 flags)
{
struct netsec_priv *priv = netdev_priv(ndev);
struct netsec_desc_ring *tx_ring = &priv->desc_ring[NETSEC_RING_TX];
int drops = 0;
int i;
if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
return -EINVAL;
spin_lock(&tx_ring->lock);
for (i = 0; i < n; i++) {
struct xdp_frame *xdpf = frames[i];
int err;
err = netsec_xdp_queue_one(priv, xdpf, true);
if (err != NETSEC_XDP_TX) {
xdp_return_frame_rx_napi(xdpf);
drops++;
} else {
tx_ring->xdp_xmit++;
}
}
spin_unlock(&tx_ring->lock);
if (unlikely(flags & XDP_XMIT_FLUSH)) {
netsec_xdp_ring_tx_db(priv, tx_ring->xdp_xmit);
tx_ring->xdp_xmit = 0;
}
return n - drops;
}
static int netsec_xdp_setup(struct netsec_priv *priv, struct bpf_prog *prog,
struct netlink_ext_ack *extack)
{
struct net_device *dev = priv->ndev;
struct bpf_prog *old_prog;
/* For now just support only the usual MTU sized frames */
if (prog && dev->mtu > 1500) {
NL_SET_ERR_MSG_MOD(extack, "Jumbo frames not supported on XDP");
return -EOPNOTSUPP;
}
if (netif_running(dev))
netsec_netdev_stop(dev);
/* Detach old prog, if any */
old_prog = xchg(&priv->xdp_prog, prog);
if (old_prog)
bpf_prog_put(old_prog);
if (netif_running(dev))
netsec_netdev_open(dev);
return 0;
}
static int netsec_xdp(struct net_device *ndev, struct netdev_bpf *xdp)
{
struct netsec_priv *priv = netdev_priv(ndev);
switch (xdp->command) {
case XDP_SETUP_PROG:
return netsec_xdp_setup(priv, xdp->prog, xdp->extack);
case XDP_QUERY_PROG:
xdp->prog_id = priv->xdp_prog ? priv->xdp_prog->aux->id : 0;
return 0;
default:
return -EINVAL;
}
}
static const struct net_device_ops netsec_netdev_ops = {
.ndo_init = netsec_netdev_init,
.ndo_uninit = netsec_netdev_uninit,
@ -1537,6 +1842,8 @@ static const struct net_device_ops netsec_netdev_ops = {
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
.ndo_do_ioctl = netsec_netdev_ioctl,
.ndo_xdp_xmit = netsec_xdp_xmit,
.ndo_bpf = netsec_xdp,
};
static int netsec_of_probe(struct platform_device *pdev,