net: ethernet: mtk_eth_soc: rely on page_pool for single page buffers
authorLorenzo Bianconi <lorenzo@kernel.org>
Fri, 22 Jul 2022 07:19:36 +0000 (09:19 +0200)
committerDavid S. Miller <davem@davemloft.net>
Mon, 25 Jul 2022 09:38:57 +0000 (10:38 +0100)
Rely on page_pool allocator for single page buffers in order to keep
them dma mapped and add skb recycling support.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/mediatek/Kconfig
drivers/net/ethernet/mediatek/mtk_eth_soc.c
drivers/net/ethernet/mediatek/mtk_eth_soc.h

index da4ec23..d2422c7 100644 (file)
@@ -17,6 +17,7 @@ config NET_MEDIATEK_SOC
        select PINCTRL
        select PHYLINK
        select DIMLIB
+       select PAGE_POOL
        help
          This driver supports the gigabit ethernet MACs in the
          MediaTek SoC family.
index 6beb3d4..9a92d60 100644 (file)
@@ -1432,6 +1432,68 @@ static void mtk_update_rx_cpu_idx(struct mtk_eth *eth)
        }
 }
 
+static struct page_pool *mtk_create_page_pool(struct mtk_eth *eth,
+                                             struct xdp_rxq_info *xdp_q,
+                                             int id, int size)
+{
+       struct page_pool_params pp_params = {
+               .order = 0,
+               .flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV,
+               .pool_size = size,
+               .nid = NUMA_NO_NODE,
+               .dev = eth->dma_dev,
+               .dma_dir = DMA_FROM_DEVICE,
+               .offset = MTK_PP_HEADROOM,
+               .max_len = MTK_PP_MAX_BUF_SIZE,
+       };
+       struct page_pool *pp;
+       int err;
+
+       pp = page_pool_create(&pp_params);
+       if (IS_ERR(pp))
+               return pp;
+
+       err = __xdp_rxq_info_reg(xdp_q, &eth->dummy_dev, eth->rx_napi.napi_id,
+                                id, PAGE_SIZE);
+       if (err < 0)
+               goto err_free_pp;
+
+       err = xdp_rxq_info_reg_mem_model(xdp_q, MEM_TYPE_PAGE_POOL, pp);
+       if (err)
+               goto err_unregister_rxq;
+
+       return pp;
+
+err_unregister_rxq:
+       xdp_rxq_info_unreg(xdp_q);
+err_free_pp:
+       page_pool_destroy(pp);
+
+       return ERR_PTR(err);
+}
+
+static void *mtk_page_pool_get_buff(struct page_pool *pp, dma_addr_t *dma_addr,
+                                   gfp_t gfp_mask)
+{
+       struct page *page;
+
+       page = page_pool_alloc_pages(pp, gfp_mask | __GFP_NOWARN);
+       if (!page)
+               return NULL;
+
+       *dma_addr = page_pool_get_dma_addr(page) + MTK_PP_HEADROOM;
+       return page_address(page);
+}
+
+static void mtk_rx_put_buff(struct mtk_rx_ring *ring, void *data, bool napi)
+{
+       if (ring->page_pool)
+               page_pool_put_full_page(ring->page_pool,
+                                       virt_to_head_page(data), napi);
+       else
+               skb_free_frag(data);
+}
+
 static int mtk_poll_rx(struct napi_struct *napi, int budget,
                       struct mtk_eth *eth)
 {
@@ -1445,9 +1507,9 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
 
        while (done < budget) {
                unsigned int pktlen, *rxdcsum;
+               u32 hash, reason, reserve_len;
                struct net_device *netdev;
                dma_addr_t dma_addr;
-               u32 hash, reason;
                int mac = 0;
 
                ring = mtk_get_rx_ring(eth);
@@ -1478,36 +1540,54 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
                        goto release_desc;
 
                /* alloc new buffer */
-               if (ring->frag_size <= PAGE_SIZE)
-                       new_data = napi_alloc_frag(ring->frag_size);
-               else
-                       new_data = mtk_max_lro_buf_alloc(GFP_ATOMIC);
-               if (unlikely(!new_data)) {
-                       netdev->stats.rx_dropped++;
-                       goto release_desc;
-               }
-               dma_addr = dma_map_single(eth->dma_dev,
-                                         new_data + NET_SKB_PAD +
-                                         eth->ip_align,
-                                         ring->buf_size,
-                                         DMA_FROM_DEVICE);
-               if (unlikely(dma_mapping_error(eth->dma_dev, dma_addr))) {
-                       skb_free_frag(new_data);
-                       netdev->stats.rx_dropped++;
-                       goto release_desc;
-               }
+               if (ring->page_pool) {
+                       new_data = mtk_page_pool_get_buff(ring->page_pool,
+                                                         &dma_addr,
+                                                         GFP_ATOMIC);
+                       if (unlikely(!new_data)) {
+                               netdev->stats.rx_dropped++;
+                               goto release_desc;
+                       }
+               } else {
+                       if (ring->frag_size <= PAGE_SIZE)
+                               new_data = napi_alloc_frag(ring->frag_size);
+                       else
+                               new_data = mtk_max_lro_buf_alloc(GFP_ATOMIC);
+
+                       if (unlikely(!new_data)) {
+                               netdev->stats.rx_dropped++;
+                               goto release_desc;
+                       }
 
-               dma_unmap_single(eth->dma_dev, trxd.rxd1,
-                                ring->buf_size, DMA_FROM_DEVICE);
+                       dma_addr = dma_map_single(eth->dma_dev,
+                               new_data + NET_SKB_PAD + eth->ip_align,
+                               ring->buf_size, DMA_FROM_DEVICE);
+                       if (unlikely(dma_mapping_error(eth->dma_dev,
+                                                      dma_addr))) {
+                               skb_free_frag(new_data);
+                               netdev->stats.rx_dropped++;
+                               goto release_desc;
+                       }
+
+                       dma_unmap_single(eth->dma_dev, trxd.rxd1,
+                                        ring->buf_size, DMA_FROM_DEVICE);
+               }
 
                /* receive data */
                skb = build_skb(data, ring->frag_size);
                if (unlikely(!skb)) {
-                       skb_free_frag(data);
+                       mtk_rx_put_buff(ring, data, true);
                        netdev->stats.rx_dropped++;
                        goto skip_rx;
                }
-               skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
+
+               if (ring->page_pool) {
+                       reserve_len = MTK_PP_HEADROOM;
+                       skb_mark_for_recycle(skb);
+               } else {
+                       reserve_len = NET_SKB_PAD + NET_IP_ALIGN;
+               }
+               skb_reserve(skb, reserve_len);
 
                pktlen = RX_DMA_GET_PLEN0(trxd.rxd2);
                skb->dev = netdev;
@@ -1561,7 +1641,6 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
 skip_rx:
                ring->data[idx] = new_data;
                rxd->rxd1 = (unsigned int)dma_addr;
-
 release_desc:
                if (MTK_HAS_CAPS(eth->soc->caps, MTK_SOC_MT7628))
                        rxd->rxd2 = RX_DMA_LSO;
@@ -1569,7 +1648,6 @@ release_desc:
                        rxd->rxd2 = RX_DMA_PREP_PLEN0(ring->buf_size);
 
                ring->calc_idx = idx;
-
                done++;
        }
 
@@ -1933,13 +2011,15 @@ static int mtk_rx_alloc(struct mtk_eth *eth, int ring_no, int rx_flag)
        if (!ring->data)
                return -ENOMEM;
 
-       for (i = 0; i < rx_dma_size; i++) {
-               if (ring->frag_size <= PAGE_SIZE)
-                       ring->data[i] = netdev_alloc_frag(ring->frag_size);
-               else
-                       ring->data[i] = mtk_max_lro_buf_alloc(GFP_KERNEL);
-               if (!ring->data[i])
-                       return -ENOMEM;
+       if (!eth->hwlro) {
+               struct page_pool *pp;
+
+               pp = mtk_create_page_pool(eth, &ring->xdp_q, ring_no,
+                                         rx_dma_size);
+               if (IS_ERR(pp))
+                       return PTR_ERR(pp);
+
+               ring->page_pool = pp;
        }
 
        ring->dma = dma_alloc_coherent(eth->dma_dev,
@@ -1950,16 +2030,33 @@ static int mtk_rx_alloc(struct mtk_eth *eth, int ring_no, int rx_flag)
 
        for (i = 0; i < rx_dma_size; i++) {
                struct mtk_rx_dma_v2 *rxd;
-
-               dma_addr_t dma_addr = dma_map_single(eth->dma_dev,
-                               ring->data[i] + NET_SKB_PAD + eth->ip_align,
-                               ring->buf_size,
-                               DMA_FROM_DEVICE);
-               if (unlikely(dma_mapping_error(eth->dma_dev, dma_addr)))
-                       return -ENOMEM;
+               dma_addr_t dma_addr;
+               void *data;
 
                rxd = ring->dma + i * eth->soc->txrx.rxd_size;
+               if (ring->page_pool) {
+                       data = mtk_page_pool_get_buff(ring->page_pool,
+                                                     &dma_addr, GFP_KERNEL);
+                       if (!data)
+                               return -ENOMEM;
+               } else {
+                       if (ring->frag_size <= PAGE_SIZE)
+                               data = netdev_alloc_frag(ring->frag_size);
+                       else
+                               data = mtk_max_lro_buf_alloc(GFP_KERNEL);
+
+                       if (!data)
+                               return -ENOMEM;
+
+                       dma_addr = dma_map_single(eth->dma_dev,
+                               data + NET_SKB_PAD + eth->ip_align,
+                               ring->buf_size, DMA_FROM_DEVICE);
+                       if (unlikely(dma_mapping_error(eth->dma_dev,
+                                                      dma_addr)))
+                               return -ENOMEM;
+               }
                rxd->rxd1 = (unsigned int)dma_addr;
+               ring->data[i] = data;
 
                if (MTK_HAS_CAPS(eth->soc->caps, MTK_SOC_MT7628))
                        rxd->rxd2 = RX_DMA_LSO;
@@ -1975,6 +2072,7 @@ static int mtk_rx_alloc(struct mtk_eth *eth, int ring_no, int rx_flag)
                        rxd->rxd8 = 0;
                }
        }
+
        ring->dma_size = rx_dma_size;
        ring->calc_idx_update = false;
        ring->calc_idx = rx_dma_size - 1;
@@ -2026,7 +2124,7 @@ static void mtk_rx_clean(struct mtk_eth *eth, struct mtk_rx_ring *ring)
 
                        dma_unmap_single(eth->dma_dev, rxd->rxd1,
                                         ring->buf_size, DMA_FROM_DEVICE);
-                       skb_free_frag(ring->data[i]);
+                       mtk_rx_put_buff(ring, ring->data[i], false);
                }
                kfree(ring->data);
                ring->data = NULL;
@@ -2038,6 +2136,13 @@ static void mtk_rx_clean(struct mtk_eth *eth, struct mtk_rx_ring *ring)
                                  ring->dma, ring->phys);
                ring->dma = NULL;
        }
+
+       if (ring->page_pool) {
+               if (xdp_rxq_info_is_reg(&ring->xdp_q))
+                       xdp_rxq_info_unreg(&ring->xdp_q);
+               page_pool_destroy(ring->page_pool);
+               ring->page_pool = NULL;
+       }
 }
 
 static int mtk_hwlro_rx_init(struct mtk_eth *eth)
index 0a63289..26c0193 100644 (file)
@@ -18,6 +18,8 @@
 #include <linux/rhashtable.h>
 #include <linux/dim.h>
 #include <linux/bitfield.h>
+#include <net/page_pool.h>
+#include <linux/bpf_trace.h>
 #include "mtk_ppe.h"
 
 #define MTK_QDMA_PAGE_SIZE     2048
 #define MTK_HW_FEATURES_MT7628 (NETIF_F_SG | NETIF_F_RXCSUM)
 #define NEXT_DESP_IDX(X, Y)    (((X) + 1) & ((Y) - 1))
 
+#define MTK_PP_HEADROOM                XDP_PACKET_HEADROOM
+#define MTK_PP_PAD             (MTK_PP_HEADROOM + \
+                                SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
+#define MTK_PP_MAX_BUF_SIZE    (PAGE_SIZE - MTK_PP_PAD)
+
 #define MTK_QRX_OFFSET         0x10
 
 #define MTK_MAX_RX_RING_NUM    4
@@ -745,6 +752,9 @@ struct mtk_rx_ring {
        bool calc_idx_update;
        u16 calc_idx;
        u32 crx_idx_reg;
+       /* page_pool */
+       struct page_pool *page_pool;
+       struct xdp_rxq_info xdp_q;
 };
 
 enum mkt_eth_capabilities {