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path: root/drivers/net/ethernet/mellanox/mlx4/en_rx.c
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Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx4/en_rx.c')
-rw-r--r--drivers/net/ethernet/mellanox/mlx4/en_rx.c126
1 files changed, 114 insertions, 12 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 99b5407f2278..2040dad8611d 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -32,6 +32,7 @@
*/
#include <net/busy_poll.h>
+#include <linux/bpf.h>
#include <linux/mlx4/cq.h>
#include <linux/slab.h>
#include <linux/mlx4/qp.h>
@@ -57,7 +58,7 @@ static int mlx4_alloc_pages(struct mlx4_en_priv *priv,
struct page *page;
dma_addr_t dma;
- for (order = MLX4_EN_ALLOC_PREFER_ORDER; ;) {
+ for (order = frag_info->order; ;) {
gfp_t gfp = _gfp;
if (order)
@@ -70,7 +71,7 @@ static int mlx4_alloc_pages(struct mlx4_en_priv *priv,
return -ENOMEM;
}
dma = dma_map_page(priv->ddev, page, 0, PAGE_SIZE << order,
- PCI_DMA_FROMDEVICE);
+ frag_info->dma_dir);
if (dma_mapping_error(priv->ddev, dma)) {
put_page(page);
return -ENOMEM;
@@ -124,7 +125,8 @@ out:
while (i--) {
if (page_alloc[i].page != ring_alloc[i].page) {
dma_unmap_page(priv->ddev, page_alloc[i].dma,
- page_alloc[i].page_size, PCI_DMA_FROMDEVICE);
+ page_alloc[i].page_size,
+ priv->frag_info[i].dma_dir);
page = page_alloc[i].page;
/* Revert changes done by mlx4_alloc_pages */
page_ref_sub(page, page_alloc[i].page_size /
@@ -145,7 +147,7 @@ static void mlx4_en_free_frag(struct mlx4_en_priv *priv,
if (next_frag_end > frags[i].page_size)
dma_unmap_page(priv->ddev, frags[i].dma, frags[i].page_size,
- PCI_DMA_FROMDEVICE);
+ frag_info->dma_dir);
if (frags[i].page)
put_page(frags[i].page);
@@ -176,7 +178,8 @@ out:
page_alloc = &ring->page_alloc[i];
dma_unmap_page(priv->ddev, page_alloc->dma,
- page_alloc->page_size, PCI_DMA_FROMDEVICE);
+ page_alloc->page_size,
+ priv->frag_info[i].dma_dir);
page = page_alloc->page;
/* Revert changes done by mlx4_alloc_pages */
page_ref_sub(page, page_alloc->page_size /
@@ -201,7 +204,7 @@ static void mlx4_en_destroy_allocator(struct mlx4_en_priv *priv,
i, page_count(page_alloc->page));
dma_unmap_page(priv->ddev, page_alloc->dma,
- page_alloc->page_size, PCI_DMA_FROMDEVICE);
+ page_alloc->page_size, frag_info->dma_dir);
while (page_alloc->page_offset + frag_info->frag_stride <
page_alloc->page_size) {
put_page(page_alloc->page);
@@ -244,6 +247,12 @@ static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
struct mlx4_en_rx_alloc *frags = ring->rx_info +
(index << priv->log_rx_info);
+ if (ring->page_cache.index > 0) {
+ frags[0] = ring->page_cache.buf[--ring->page_cache.index];
+ rx_desc->data[0].addr = cpu_to_be64(frags[0].dma);
+ return 0;
+ }
+
return mlx4_en_alloc_frags(priv, rx_desc, frags, ring->page_alloc, gfp);
}
@@ -502,13 +511,35 @@ void mlx4_en_recover_from_oom(struct mlx4_en_priv *priv)
}
}
+/* When the rx ring is running in page-per-packet mode, a released frame can go
+ * directly into a small cache, to avoid unmapping or touching the page
+ * allocator. In bpf prog performance scenarios, buffers are either forwarded
+ * or dropped, never converted to skbs, so every page can come directly from
+ * this cache when it is sized to be a multiple of the napi budget.
+ */
+bool mlx4_en_rx_recycle(struct mlx4_en_rx_ring *ring,
+ struct mlx4_en_rx_alloc *frame)
+{
+ struct mlx4_en_page_cache *cache = &ring->page_cache;
+
+ if (cache->index >= MLX4_EN_CACHE_SIZE)
+ return false;
+
+ cache->buf[cache->index++] = *frame;
+ return true;
+}
+
void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
struct mlx4_en_rx_ring **pring,
u32 size, u16 stride)
{
struct mlx4_en_dev *mdev = priv->mdev;
struct mlx4_en_rx_ring *ring = *pring;
+ struct bpf_prog *old_prog;
+ old_prog = READ_ONCE(ring->xdp_prog);
+ if (old_prog)
+ bpf_prog_put(old_prog);
mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * stride + TXBB_SIZE);
vfree(ring->rx_info);
ring->rx_info = NULL;
@@ -519,6 +550,16 @@ void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
struct mlx4_en_rx_ring *ring)
{
+ int i;
+
+ for (i = 0; i < ring->page_cache.index; i++) {
+ struct mlx4_en_rx_alloc *frame = &ring->page_cache.buf[i];
+
+ dma_unmap_page(priv->ddev, frame->dma, frame->page_size,
+ priv->frag_info[0].dma_dir);
+ put_page(frame->page);
+ }
+ ring->page_cache.index = 0;
mlx4_en_free_rx_buf(priv, ring);
if (ring->stride <= TXBB_SIZE)
ring->buf -= TXBB_SIZE;
@@ -740,7 +781,10 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
struct mlx4_en_rx_ring *ring = priv->rx_ring[cq->ring];
struct mlx4_en_rx_alloc *frags;
struct mlx4_en_rx_desc *rx_desc;
+ struct bpf_prog *xdp_prog;
+ int doorbell_pending;
struct sk_buff *skb;
+ int tx_index;
int index;
int nr;
unsigned int length;
@@ -756,6 +800,10 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
if (budget <= 0)
return polled;
+ xdp_prog = READ_ONCE(ring->xdp_prog);
+ doorbell_pending = 0;
+ tx_index = (priv->tx_ring_num - priv->xdp_ring_num) + cq->ring;
+
/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
* descriptor offset can be deduced from the CQE index instead of
* reading 'cqe->index' */
@@ -832,6 +880,43 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
l2_tunnel = (dev->hw_enc_features & NETIF_F_RXCSUM) &&
(cqe->vlan_my_qpn & cpu_to_be32(MLX4_CQE_L2_TUNNEL));
+ /* A bpf program gets first chance to drop the packet. It may
+ * read bytes but not past the end of the frag.
+ */
+ if (xdp_prog) {
+ struct xdp_buff xdp;
+ dma_addr_t dma;
+ u32 act;
+
+ dma = be64_to_cpu(rx_desc->data[0].addr);
+ dma_sync_single_for_cpu(priv->ddev, dma,
+ priv->frag_info[0].frag_size,
+ DMA_FROM_DEVICE);
+
+ xdp.data = page_address(frags[0].page) +
+ frags[0].page_offset;
+ xdp.data_end = xdp.data + length;
+
+ act = bpf_prog_run_xdp(xdp_prog, &xdp);
+ switch (act) {
+ case XDP_PASS:
+ break;
+ case XDP_TX:
+ if (!mlx4_en_xmit_frame(frags, dev,
+ length, tx_index,
+ &doorbell_pending))
+ goto consumed;
+ break;
+ default:
+ bpf_warn_invalid_xdp_action(act);
+ case XDP_ABORTED:
+ case XDP_DROP:
+ if (mlx4_en_rx_recycle(ring, frags))
+ goto consumed;
+ goto next;
+ }
+ }
+
if (likely(dev->features & NETIF_F_RXCSUM)) {
if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_TCP |
MLX4_CQE_STATUS_UDP)) {
@@ -983,6 +1068,7 @@ next:
for (nr = 0; nr < priv->num_frags; nr++)
mlx4_en_free_frag(priv, frags, nr);
+consumed:
++cq->mcq.cons_index;
index = (cq->mcq.cons_index) & ring->size_mask;
cqe = mlx4_en_get_cqe(cq->buf, index, priv->cqe_size) + factor;
@@ -991,6 +1077,9 @@ next:
}
out:
+ if (doorbell_pending)
+ mlx4_en_xmit_doorbell(priv->tx_ring[tx_index]);
+
AVG_PERF_COUNTER(priv->pstats.rx_coal_avg, polled);
mlx4_cq_set_ci(&cq->mcq);
wmb(); /* ensure HW sees CQ consumer before we post new buffers */
@@ -1058,22 +1147,35 @@ static const int frag_sizes[] = {
void mlx4_en_calc_rx_buf(struct net_device *dev)
{
+ enum dma_data_direction dma_dir = PCI_DMA_FROMDEVICE;
struct mlx4_en_priv *priv = netdev_priv(dev);
- /* VLAN_HLEN is added twice,to support skb vlan tagged with multiple
- * headers. (For example: ETH_P_8021Q and ETH_P_8021AD).
- */
- int eff_mtu = dev->mtu + ETH_HLEN + (2 * VLAN_HLEN);
+ int eff_mtu = MLX4_EN_EFF_MTU(dev->mtu);
+ int order = MLX4_EN_ALLOC_PREFER_ORDER;
+ u32 align = SMP_CACHE_BYTES;
int buf_size = 0;
int i = 0;
+ /* bpf requires buffers to be set up as 1 packet per page.
+ * This only works when num_frags == 1.
+ */
+ if (priv->xdp_ring_num) {
+ dma_dir = PCI_DMA_BIDIRECTIONAL;
+ /* This will gain efficient xdp frame recycling at the expense
+ * of more costly truesize accounting
+ */
+ align = PAGE_SIZE;
+ order = 0;
+ }
+
while (buf_size < eff_mtu) {
+ priv->frag_info[i].order = order;
priv->frag_info[i].frag_size =
(eff_mtu > buf_size + frag_sizes[i]) ?
frag_sizes[i] : eff_mtu - buf_size;
priv->frag_info[i].frag_prefix_size = buf_size;
priv->frag_info[i].frag_stride =
- ALIGN(priv->frag_info[i].frag_size,
- SMP_CACHE_BYTES);
+ ALIGN(priv->frag_info[i].frag_size, align);
+ priv->frag_info[i].dma_dir = dma_dir;
buf_size += priv->frag_info[i].frag_size;
i++;
}
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