On 7/13/21, Yunsheng Lin <linyunsheng@xxxxxxxxxx> wrote:
> This patch adds skb's frag page recycling support based on
> the elevated refcnt support in page pool.
>
> The performance improves above 10~20% with IOMMU disabled.
> The performance improves about 200% when IOMMU is enabled
> and iperf server shares the same cpu with irq/NAPI.
Could you share workload details?
>
> Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
> ---
> drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 79
> +++++++++++++++++++++++--
> drivers/net/ethernet/hisilicon/hns3/hns3_enet.h | 3 +
> 2 files changed, 77 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
> b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
> index cdb5f14..c799129 100644
> --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
> +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
> @@ -3205,6 +3205,21 @@ static int hns3_alloc_buffer(struct hns3_enet_ring
> *ring,
> unsigned int order = hns3_page_order(ring);
> struct page *p;
>
> + if (ring->page_pool) {
> + p = page_pool_dev_alloc_frag(ring->page_pool,
> + &cb->page_offset,
> + hns3_buf_size(ring));
> + if (unlikely(!p))
> + return -ENOMEM;
> +
> + cb->priv = p;
> + cb->buf = page_address(p);
> + cb->dma = page_pool_get_dma_addr(p);
> + cb->type = DESC_TYPE_FRAG;
> + cb->reuse_flag = 0;
> + return 0;
> + }
> +
> p = dev_alloc_pages(order);
> if (!p)
> return -ENOMEM;
> @@ -3227,8 +3242,12 @@ static void hns3_free_buffer(struct hns3_enet_ring
> *ring,
> if (cb->type & (DESC_TYPE_SKB | DESC_TYPE_BOUNCE_HEAD |
> DESC_TYPE_BOUNCE_ALL | DESC_TYPE_SGL_SKB))
> napi_consume_skb(cb->priv, budget);
> - else if (!HNAE3_IS_TX_RING(ring) && cb->pagecnt_bias)
> - __page_frag_cache_drain(cb->priv, cb->pagecnt_bias);
> + else if (!HNAE3_IS_TX_RING(ring)) {
> + if (cb->type & DESC_TYPE_PAGE && cb->pagecnt_bias)
> + __page_frag_cache_drain(cb->priv, cb->pagecnt_bias);
> + else if (cb->type & DESC_TYPE_FRAG)
> + page_pool_put_full_page(ring->page_pool, cb->priv, false);
> + }
> memset(cb, 0, sizeof(*cb));
> }
>
> @@ -3315,7 +3334,7 @@ static int hns3_alloc_and_map_buffer(struct
> hns3_enet_ring *ring,
> int ret;
>
> ret = hns3_alloc_buffer(ring, cb);
> - if (ret)
> + if (ret || ring->page_pool)
> goto out;
>
> ret = hns3_map_buffer(ring, cb);
> @@ -3337,7 +3356,8 @@ static int hns3_alloc_and_attach_buffer(struct
> hns3_enet_ring *ring, int i)
> if (ret)
> return ret;
>
> - ring->desc[i].addr = cpu_to_le64(ring->desc_cb[i].dma);
> + ring->desc[i].addr = cpu_to_le64(ring->desc_cb[i].dma +
> + ring->desc_cb[i].page_offset);
>
> return 0;
> }
> @@ -3367,7 +3387,8 @@ static void hns3_replace_buffer(struct hns3_enet_ring
> *ring, int i,
> {
> hns3_unmap_buffer(ring, &ring->desc_cb[i]);
> ring->desc_cb[i] = *res_cb;
> - ring->desc[i].addr = cpu_to_le64(ring->desc_cb[i].dma);
> + ring->desc[i].addr = cpu_to_le64(ring->desc_cb[i].dma +
> + ring->desc_cb[i].page_offset);
> ring->desc[i].rx.bd_base_info = 0;
> }
>
> @@ -3539,6 +3560,12 @@ static void hns3_nic_reuse_page(struct sk_buff *skb,
> int i,
> u32 frag_size = size - pull_len;
> bool reused;
>
> + if (ring->page_pool) {
> + skb_add_rx_frag(skb, i, desc_cb->priv, frag_offset,
> + frag_size, truesize);
> + return;
> + }
> +
> /* Avoid re-using remote or pfmem page */
> if (unlikely(!dev_page_is_reusable(desc_cb->priv)))
> goto out;
> @@ -3856,6 +3883,9 @@ static int hns3_alloc_skb(struct hns3_enet_ring *ring,
> unsigned int length,
> /* We can reuse buffer as-is, just make sure it is reusable */
> if (dev_page_is_reusable(desc_cb->priv))
> desc_cb->reuse_flag = 1;
> + else if (desc_cb->type & DESC_TYPE_FRAG)
> + page_pool_put_full_page(ring->page_pool, desc_cb->priv,
> + false);
> else /* This page cannot be reused so discard it */
> __page_frag_cache_drain(desc_cb->priv,
> desc_cb->pagecnt_bias);
> @@ -3863,6 +3893,10 @@ static int hns3_alloc_skb(struct hns3_enet_ring
> *ring, unsigned int length,
> hns3_rx_ring_move_fw(ring);
> return 0;
> }
> +
> + if (ring->page_pool)
> + skb_mark_for_recycle(skb);
> +
> u64_stats_update_begin(&ring->syncp);
> ring->stats.seg_pkt_cnt++;
> u64_stats_update_end(&ring->syncp);
> @@ -3901,6 +3935,10 @@ static int hns3_add_frag(struct hns3_enet_ring
> *ring)
> "alloc rx fraglist skb fail\n");
> return -ENXIO;
> }
> +
> + if (ring->page_pool)
> + skb_mark_for_recycle(new_skb);
> +
> ring->frag_num = 0;
>
> if (ring->tail_skb) {
> @@ -4705,6 +4743,29 @@ static void hns3_put_ring_config(struct hns3_nic_priv
> *priv)
> priv->ring = NULL;
> }
>
> +static void hns3_alloc_page_pool(struct hns3_enet_ring *ring)
> +{
> + struct page_pool_params pp_params = {
> + .flags = PP_FLAG_DMA_MAP | PP_FLAG_PAGE_FRAG,
> + .order = hns3_page_order(ring),
> + .pool_size = ring->desc_num * hns3_buf_size(ring) / PAGE_SIZE,
> + .nid = dev_to_node(ring_to_dev(ring)),
> + .dev = ring_to_dev(ring),
> + .dma_dir = DMA_FROM_DEVICE,
> + .offset = 0,
> + .max_len = 0,
> + };
> +
> + ring->page_pool = page_pool_create(&pp_params);
> + if (IS_ERR(ring->page_pool)) {
> + dev_warn(ring_to_dev(ring), "page pool creation failed: %ld\n",
> + PTR_ERR(ring->page_pool));
> + ring->page_pool = NULL;
> + } else {
> + dev_info(ring_to_dev(ring), "page pool creation succeeded\n");
> + }
> +}
> +
> static int hns3_alloc_ring_memory(struct hns3_enet_ring *ring)
> {
> int ret;
> @@ -4724,6 +4785,8 @@ static int hns3_alloc_ring_memory(struct
> hns3_enet_ring *ring)
> goto out_with_desc_cb;
>
> if (!HNAE3_IS_TX_RING(ring)) {
> + hns3_alloc_page_pool(ring);
> +
> ret = hns3_alloc_ring_buffers(ring);
> if (ret)
> goto out_with_desc;
> @@ -4764,6 +4827,12 @@ void hns3_fini_ring(struct hns3_enet_ring *ring)
> devm_kfree(ring_to_dev(ring), tx_spare);
> ring->tx_spare = NULL;
> }
> +
> + if (!HNAE3_IS_TX_RING(ring) && ring->page_pool) {
> + page_pool_destroy(ring->page_pool);
> + ring->page_pool = NULL;
> + dev_info(ring_to_dev(ring), "page pool destroyed\n");
> + }
> }
>
> static int hns3_buf_size2type(u32 buf_size)
> diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
> b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
> index 15af3d9..115c0ce 100644
> --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
> +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
> @@ -6,6 +6,7 @@
>
> #include <linux/dim.h>
> #include <linux/if_vlan.h>
> +#include <net/page_pool.h>
>
> #include "hnae3.h"
>
> @@ -307,6 +308,7 @@ enum hns3_desc_type {
> DESC_TYPE_BOUNCE_ALL = 1 << 3,
> DESC_TYPE_BOUNCE_HEAD = 1 << 4,
> DESC_TYPE_SGL_SKB = 1 << 5,
> + DESC_TYPE_FRAG = 1 << 6,
> };
>
> struct hns3_desc_cb {
> @@ -451,6 +453,7 @@ struct hns3_enet_ring {
> struct hnae3_queue *tqp;
> int queue_index;
> struct device *dev; /* will be used for DMA mapping of descriptors */
> + struct page_pool *page_pool;
>
> /* statistic */
> struct ring_stats stats;
> --
> 2.7.4
>
>
