From: Alexander Lobakin Date: Fri, 10 Feb 2023 17:06:17 +0000 (+0100) Subject: ice: Fix freeing XDP frames backed by Page Pool X-Git-Tag: v6.6.7~3490^2~13^2~34^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=055d0920685e53ed8c2ad914888724d69dca17c6;p=platform%2Fkernel%2Flinux-starfive.git ice: Fix freeing XDP frames backed by Page Pool As already mentioned, freeing any &xdp_frame via page_frag_free() is wrong, as it assumes the frame is backed by either an order-0 page or a page with no "patrons" behind them, while in fact frames backed by Page Pool can be redirected to a device, which's driver doesn't use it. Keep storing a pointer to the raw buffer and then freeing it unconditionally via page_frag_free() for %XDP_TX frames, but introduce a separate type in the enum for frames coming through .ndo_xdp_xmit(), and free them via xdp_return_frame_bulk(). Note that saving xdpf as xdp_buff->data_hard_start is intentional and is always true when everything is configured properly. After this change, %XDP_REDIRECT from a Page Pool based driver to ice becomes zero-alloc as it should be and horrendous 3.3 Mpps / queue turn into 6.6, hehe. Let it go with no "Fixes:" tag as it spans across good 5+ commits and can't be trivially backported. Signed-off-by: Alexander Lobakin Signed-off-by: Daniel Borkmann Acked-by: Maciej Fijalkowski Link: https://lore.kernel.org/bpf/20230210170618.1973430-6-alexandr.lobakin@intel.com --- diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index d7e8a3f..e451276 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -128,6 +128,9 @@ ice_unmap_and_free_tx_buf(struct ice_tx_ring *ring, struct ice_tx_buf *tx_buf) case ICE_TX_BUF_XDP_TX: page_frag_free(tx_buf->raw_buf); break; + case ICE_TX_BUF_XDP_XMIT: + xdp_return_frame(tx_buf->xdpf); + break; } tx_buf->next_to_watch = NULL; @@ -575,7 +578,7 @@ ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp, case XDP_TX: if (static_branch_unlikely(&ice_xdp_locking_key)) spin_lock(&xdp_ring->tx_lock); - ret = __ice_xmit_xdp_ring(xdp, xdp_ring); + ret = __ice_xmit_xdp_ring(xdp, xdp_ring, false); if (static_branch_unlikely(&ice_xdp_locking_key)) spin_unlock(&xdp_ring->tx_lock); if (ret == ICE_XDP_CONSUMED) diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.h b/drivers/net/ethernet/intel/ice/ice_txrx.h index 18d8ba0..fff0efe 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.h +++ b/drivers/net/ethernet/intel/ice/ice_txrx.h @@ -153,6 +153,7 @@ static inline int ice_skb_pad(void) * @ICE_TX_BUF_FRAG: mapped skb OR &xdp_buff frag, only unmap DMA * @ICE_TX_BUF_SKB: &sk_buff, unmap and consume_skb(), update stats * @ICE_TX_BUF_XDP_TX: &xdp_buff, unmap and page_frag_free(), stats + * @ICE_TX_BUF_XDP_XMIT: &xdp_frame, unmap and xdp_return_frame(), stats * @ICE_TX_BUF_XSK_TX: &xdp_buff on XSk queue, xsk_buff_free(), stats */ enum ice_tx_buf_type { @@ -161,6 +162,7 @@ enum ice_tx_buf_type { ICE_TX_BUF_FRAG, ICE_TX_BUF_SKB, ICE_TX_BUF_XDP_TX, + ICE_TX_BUF_XDP_XMIT, ICE_TX_BUF_XSK_TX, }; @@ -172,6 +174,7 @@ struct ice_tx_buf { union { void *raw_buf; /* used for XDP_TX and FDir rules */ struct sk_buff *skb; /* used for .ndo_start_xmit() */ + struct xdp_frame *xdpf; /* used for .ndo_xdp_xmit() */ struct xdp_buff *xdp; /* used for XDP_TX ZC */ }; unsigned int bytecount; diff --git a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c index 23ac482..6d98c34 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c @@ -222,13 +222,15 @@ ice_receive_skb(struct ice_rx_ring *rx_ring, struct sk_buff *skb, u16 vlan_tag) /** * ice_clean_xdp_tx_buf - Free and unmap XDP Tx buffer - * @xdp_ring: XDP Tx ring + * @dev: device for DMA mapping * @tx_buf: Tx buffer to clean + * @bq: XDP bulk flush struct */ static void -ice_clean_xdp_tx_buf(struct ice_tx_ring *xdp_ring, struct ice_tx_buf *tx_buf) +ice_clean_xdp_tx_buf(struct device *dev, struct ice_tx_buf *tx_buf, + struct xdp_frame_bulk *bq) { - dma_unmap_single(xdp_ring->dev, dma_unmap_addr(tx_buf, dma), + dma_unmap_single(dev, dma_unmap_addr(tx_buf, dma), dma_unmap_len(tx_buf, len), DMA_TO_DEVICE); dma_unmap_len_set(tx_buf, len, 0); @@ -236,6 +238,9 @@ ice_clean_xdp_tx_buf(struct ice_tx_ring *xdp_ring, struct ice_tx_buf *tx_buf) case ICE_TX_BUF_XDP_TX: page_frag_free(tx_buf->raw_buf); break; + case ICE_TX_BUF_XDP_XMIT: + xdp_return_frame_bulk(tx_buf->xdpf, bq); + break; } tx_buf->type = ICE_TX_BUF_EMPTY; @@ -248,9 +253,11 @@ ice_clean_xdp_tx_buf(struct ice_tx_ring *xdp_ring, struct ice_tx_buf *tx_buf) static u32 ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring) { int total_bytes = 0, total_pkts = 0; + struct device *dev = xdp_ring->dev; u32 ntc = xdp_ring->next_to_clean; struct ice_tx_desc *tx_desc; u32 cnt = xdp_ring->count; + struct xdp_frame_bulk bq; u32 frags, xdp_tx = 0; u32 ready_frames = 0; u32 idx; @@ -270,6 +277,9 @@ static u32 ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring) return 0; ret = ready_frames; + xdp_frame_bulk_init(&bq); + rcu_read_lock(); /* xdp_return_frame_bulk() */ + while (ready_frames) { struct ice_tx_buf *tx_buf = &xdp_ring->tx_buf[ntc]; struct ice_tx_buf *head = tx_buf; @@ -289,15 +299,18 @@ static u32 ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring) for (int i = 0; i < frags; i++) { tx_buf = &xdp_ring->tx_buf[ntc]; - ice_clean_xdp_tx_buf(xdp_ring, tx_buf); + ice_clean_xdp_tx_buf(dev, tx_buf, &bq); ntc++; if (ntc == cnt) ntc = 0; } - ice_clean_xdp_tx_buf(xdp_ring, head); + ice_clean_xdp_tx_buf(dev, head, &bq); } + xdp_flush_frame_bulk(&bq); + rcu_read_unlock(); + tx_desc->cmd_type_offset_bsz = 0; xdp_ring->next_to_clean = ntc; xdp_ring->xdp_tx_active -= xdp_tx; @@ -310,8 +323,10 @@ static u32 ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring) * __ice_xmit_xdp_ring - submit frame to XDP ring for transmission * @xdp: XDP buffer to be placed onto Tx descriptors * @xdp_ring: XDP ring for transmission + * @frame: whether this comes from .ndo_xdp_xmit() */ -int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring) +int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring, + bool frame) { struct skb_shared_info *sinfo = NULL; u32 size = xdp->data_end - xdp->data; @@ -355,10 +370,15 @@ int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring) dma_unmap_len_set(tx_buf, len, size); dma_unmap_addr_set(tx_buf, dma, dma); + if (frame) { + tx_buf->type = ICE_TX_BUF_FRAG; + } else { + tx_buf->type = ICE_TX_BUF_XDP_TX; + tx_buf->raw_buf = data; + } + tx_desc->buf_addr = cpu_to_le64(dma); tx_desc->cmd_type_offset_bsz = ice_build_ctob(0, 0, size, 0); - tx_buf->type = ICE_TX_BUF_XDP_TX; - tx_buf->raw_buf = data; ntu++; if (ntu == cnt) @@ -379,6 +399,11 @@ int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring) tx_head->bytecount = xdp_get_buff_len(xdp); tx_head->nr_frags = nr_frags; + if (frame) { + tx_head->type = ICE_TX_BUF_XDP_XMIT; + tx_head->xdpf = xdp->data_hard_start; + } + /* update last descriptor from a frame with EOP */ tx_desc->cmd_type_offset_bsz |= cpu_to_le64(ICE_TX_DESC_CMD_EOP << ICE_TXD_QW1_CMD_S); @@ -419,7 +444,7 @@ int ice_xmit_xdp_ring(struct xdp_frame *xdpf, struct ice_tx_ring *xdp_ring) struct xdp_buff xdp; xdp_convert_frame_to_buff(xdpf, &xdp); - return __ice_xmit_xdp_ring(&xdp, xdp_ring); + return __ice_xmit_xdp_ring(&xdp, xdp_ring, true); } /** diff --git a/drivers/net/ethernet/intel/ice/ice_txrx_lib.h b/drivers/net/ethernet/intel/ice/ice_txrx_lib.h index ea977f2..79efc20 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx_lib.h +++ b/drivers/net/ethernet/intel/ice/ice_txrx_lib.h @@ -143,7 +143,8 @@ static inline u32 ice_set_rs_bit(const struct ice_tx_ring *xdp_ring) void ice_finalize_xdp_rx(struct ice_tx_ring *xdp_ring, unsigned int xdp_res, u32 first_idx); int ice_xmit_xdp_buff(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring); int ice_xmit_xdp_ring(struct xdp_frame *xdpf, struct ice_tx_ring *xdp_ring); -int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring); +int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring, + bool frame); void ice_release_rx_desc(struct ice_rx_ring *rx_ring, u16 val); void ice_process_skb_fields(struct ice_rx_ring *rx_ring,