net/mlx5e: Support XDP over Striding RQ

Add XDP support over Striding RQ.
Now that linear SKB is supported over Striding RQ,
we can support XDP by setting stride size to PAGE_SIZE
and headroom to XDP_PACKET_HEADROOM.

Upon a MPWQE free, do not release pages that are being
XDP xmit, they will be released upon completions.

Striding RQ is capable of a higher packet-rate than
conventional RQ.
A performance gain is expected for all cases that had
a HW packet-rate bottleneck. This is the case whenever
using many flows that distribute to many cores.

Performance testing:
ConnectX-5, 24 rings, default MTU.
CQE compression ON (to reduce completions BW in PCI).

XDP_DROP packet rate:
--------------------------------------------------
| pkt size | XDP rate   | 100GbE linerate | pct% |
--------------------------------------------------
|   64byte | 126.2 Mpps |      148.0 Mpps |  85% |
|  128byte |  80.0 Mpps |       84.8 Mpps |  94% |
|  256byte |  42.7 Mpps |       42.7 Mpps | 100% |
|  512byte |  23.4 Mpps |       23.4 Mpps | 100% |
--------------------------------------------------

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
This commit is contained in:
Tariq Toukan 2018-02-07 14:46:36 +02:00 committed by Saeed Mahameed
parent 121e892754
commit 22f4539881
3 changed files with 26 additions and 8 deletions

View File

@ -457,6 +457,7 @@ struct mlx5e_mpw_info {
struct mlx5e_umr_dma_info umr;
u16 consumed_strides;
u16 skbs_frags[MLX5_MPWRQ_PAGES_PER_WQE];
DECLARE_BITMAP(xdp_xmit_bitmap, MLX5_MPWRQ_PAGES_PER_WQE);
};
/* a single cache unit is capable to serve one napi call (for non-striding rq)

View File

@ -200,7 +200,8 @@ bool mlx5e_striding_rq_possible(struct mlx5_core_dev *mdev,
struct mlx5e_params *params)
{
return mlx5e_check_fragmented_striding_rq_cap(mdev) &&
!params->xdp_prog && !MLX5_IPSEC_DEV(mdev);
!MLX5_IPSEC_DEV(mdev) &&
!(params->xdp_prog && !mlx5e_rx_mpwqe_is_linear_skb(mdev, params));
}
void mlx5e_set_rq_type(struct mlx5_core_dev *mdev, struct mlx5e_params *params)

View File

@ -349,13 +349,16 @@ mlx5e_copy_skb_header_mpwqe(struct device *pdev,
void mlx5e_free_rx_mpwqe(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi)
{
const bool no_xdp_xmit =
bitmap_empty(wi->xdp_xmit_bitmap, MLX5_MPWRQ_PAGES_PER_WQE);
int pg_strides = mlx5e_mpwqe_strides_per_page(rq);
struct mlx5e_dma_info *dma_info = &wi->umr.dma_info[0];
struct mlx5e_dma_info *dma_info = wi->umr.dma_info;
int i;
for (i = 0; i < MLX5_MPWRQ_PAGES_PER_WQE; i++, dma_info++) {
page_ref_sub(dma_info->page, pg_strides - wi->skbs_frags[i]);
mlx5e_page_release(rq, dma_info, true);
for (i = 0; i < MLX5_MPWRQ_PAGES_PER_WQE; i++) {
page_ref_sub(dma_info[i].page, pg_strides - wi->skbs_frags[i]);
if (no_xdp_xmit || !test_bit(i, wi->xdp_xmit_bitmap))
mlx5e_page_release(rq, &dma_info[i], true);
}
}
@ -404,6 +407,7 @@ static int mlx5e_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
}
memset(wi->skbs_frags, 0, sizeof(*wi->skbs_frags) * MLX5_MPWRQ_PAGES_PER_WQE);
bitmap_zero(wi->xdp_xmit_bitmap, MLX5_MPWRQ_PAGES_PER_WQE);
wi->consumed_strides = 0;
rq->mpwqe.umr_in_progress = true;
@ -1028,18 +1032,30 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
{
struct mlx5e_dma_info *di = &wi->umr.dma_info[page_idx];
u16 rx_headroom = rq->buff.headroom;
u32 cqe_bcnt32 = cqe_bcnt;
struct sk_buff *skb;
void *va, *data;
u32 frag_size;
bool consumed;
va = page_address(di->page) + head_offset;
data = va + rx_headroom;
frag_size = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);
frag_size = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt32);
dma_sync_single_range_for_cpu(rq->pdev, di->addr, head_offset,
frag_size, DMA_FROM_DEVICE);
prefetch(data);
skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt);
rcu_read_lock();
consumed = mlx5e_xdp_handle(rq, di, va, &rx_headroom, &cqe_bcnt32);
rcu_read_unlock();
if (consumed) {
if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags))
__set_bit(page_idx, wi->xdp_xmit_bitmap); /* non-atomic */
return NULL; /* page/packet was consumed by XDP */
}
skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt32);
if (unlikely(!skb))
return NULL;
@ -1078,7 +1094,7 @@ void mlx5e_handle_rx_cqe_mpwrq(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe)
skb = rq->mpwqe.skb_from_cqe_mpwrq(rq, wi, cqe_bcnt, head_offset,
page_idx);
if (unlikely(!skb))
if (!skb)
goto mpwrq_cqe_out;
mlx5e_complete_rx_cqe(rq, cqe, cqe_bcnt, skb);