From 126cdfe1007acb3632d054a4a68a0174bd47f17d Mon Sep 17 00:00:00 2001 From: Maciej Fijalkowski Date: Tue, 25 Jan 2022 17:04:45 +0100 Subject: [PATCH] ice: xsk: Improve AF_XDP ZC Tx and use batching API Apply the logic that was done for regular XDP from commit 9610bd988df9 ("ice: optimize XDP_TX workloads") to the ZC side of the driver. On top of that, introduce batching to Tx that is inspired by i40e's implementation with adjustments to the cleaning logic - take into the account NAPI budget in ice_clean_xdp_irq_zc(). Separating the stats structs onto separate cache lines seemed to improve the performance. Signed-off-by: Maciej Fijalkowski Signed-off-by: Daniel Borkmann Reviewed-by: Alexander Lobakin Link: https://lore.kernel.org/bpf/20220125160446.78976-8-maciej.fijalkowski@intel.com --- drivers/net/ethernet/intel/ice/ice_txrx.c | 2 +- drivers/net/ethernet/intel/ice/ice_txrx.h | 6 +- drivers/net/ethernet/intel/ice/ice_xsk.c | 256 +++++++++++++++++++----------- drivers/net/ethernet/intel/ice/ice_xsk.h | 27 +++- 4 files changed, 190 insertions(+), 101 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index 73f6049..7d8824b 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -1462,7 +1462,7 @@ int ice_napi_poll(struct napi_struct *napi, int budget) bool wd; if (tx_ring->xsk_pool) - wd = ice_clean_tx_irq_zc(tx_ring, budget); + wd = ice_xmit_zc(tx_ring, ICE_DESC_UNUSED(tx_ring), budget); else if (ice_ring_is_xdp(tx_ring)) wd = true; else diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.h b/drivers/net/ethernet/intel/ice/ice_txrx.h index 611dd7c..666db35 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.h +++ b/drivers/net/ethernet/intel/ice/ice_txrx.h @@ -322,17 +322,17 @@ struct ice_tx_ring { u16 count; /* Number of descriptors */ u16 q_index; /* Queue number of ring */ /* stats structs */ - struct ice_q_stats stats; - struct u64_stats_sync syncp; struct ice_txq_stats tx_stats; - /* CL3 - 3rd cacheline starts here */ + struct ice_q_stats stats; + struct u64_stats_sync syncp; struct rcu_head rcu; /* to avoid race on free */ DECLARE_BITMAP(xps_state, ICE_TX_NBITS); /* XPS Config State */ struct ice_channel *ch; struct ice_ptp_tx *tx_tstamps; spinlock_t tx_lock; u32 txq_teid; /* Added Tx queue TEID */ + /* CL4 - 4th cacheline starts here */ #define ICE_TX_FLAGS_RING_XDP BIT(0) u8 flags; u8 dcb_tc; /* Traffic class of ring */ diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index b12079a7..8b6acb4 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -679,134 +679,212 @@ construct_skb: } /** - * ice_xmit_zc - Completes AF_XDP entries, and cleans XDP entries + * ice_clean_xdp_tx_buf - Free and unmap XDP Tx buffer * @xdp_ring: XDP Tx ring - * @budget: max number of frames to xmit + * @tx_buf: Tx buffer to clean + */ +static void +ice_clean_xdp_tx_buf(struct ice_tx_ring *xdp_ring, struct ice_tx_buf *tx_buf) +{ + xdp_return_frame((struct xdp_frame *)tx_buf->raw_buf); + dma_unmap_single(xdp_ring->dev, dma_unmap_addr(tx_buf, dma), + dma_unmap_len(tx_buf, len), DMA_TO_DEVICE); + dma_unmap_len_set(tx_buf, len, 0); +} + +/** + * ice_clean_xdp_irq_zc - Reclaim resources after transmit completes on XDP ring + * @xdp_ring: XDP ring to clean + * @napi_budget: amount of descriptors that NAPI allows us to clean * - * Returns true if cleanup/transmission is done. + * Returns count of cleaned descriptors */ -static bool ice_xmit_zc(struct ice_tx_ring *xdp_ring, int budget) +static u16 ice_clean_xdp_irq_zc(struct ice_tx_ring *xdp_ring, int napi_budget) { - struct ice_tx_desc *tx_desc = NULL; - bool work_done = true; - struct xdp_desc desc; - dma_addr_t dma; + u16 tx_thresh = ICE_RING_QUARTER(xdp_ring); + int budget = napi_budget / tx_thresh; + u16 ntc = xdp_ring->next_to_clean; + u16 next_dd = xdp_ring->next_dd; + u16 cleared_dds = 0; - while (likely(budget-- > 0)) { + do { + struct ice_tx_desc *next_dd_desc; + u16 desc_cnt = xdp_ring->count; struct ice_tx_buf *tx_buf; + u32 xsk_frames; + u16 i; - if (unlikely(!ICE_DESC_UNUSED(xdp_ring))) { - xdp_ring->tx_stats.tx_busy++; - work_done = false; - break; - } - - tx_buf = &xdp_ring->tx_buf[xdp_ring->next_to_use]; - - if (!xsk_tx_peek_desc(xdp_ring->xsk_pool, &desc)) + next_dd_desc = ICE_TX_DESC(xdp_ring, next_dd); + if (!(next_dd_desc->cmd_type_offset_bsz & + cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE))) break; - dma = xsk_buff_raw_get_dma(xdp_ring->xsk_pool, desc.addr); - xsk_buff_raw_dma_sync_for_device(xdp_ring->xsk_pool, dma, - desc.len); + cleared_dds++; + xsk_frames = 0; - tx_buf->bytecount = desc.len; + for (i = 0; i < tx_thresh; i++) { + tx_buf = &xdp_ring->tx_buf[ntc]; - tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_to_use); - tx_desc->buf_addr = cpu_to_le64(dma); - tx_desc->cmd_type_offset_bsz = - ice_build_ctob(ICE_TXD_LAST_DESC_CMD, 0, desc.len, 0); + if (tx_buf->raw_buf) { + ice_clean_xdp_tx_buf(xdp_ring, tx_buf); + tx_buf->raw_buf = NULL; + } else { + xsk_frames++; + } - xdp_ring->next_to_use++; - if (xdp_ring->next_to_use == xdp_ring->count) - xdp_ring->next_to_use = 0; - } + ntc++; + if (ntc >= xdp_ring->count) + ntc = 0; + } + if (xsk_frames) + xsk_tx_completed(xdp_ring->xsk_pool, xsk_frames); + next_dd_desc->cmd_type_offset_bsz = 0; + next_dd = next_dd + tx_thresh; + if (next_dd >= desc_cnt) + next_dd = tx_thresh - 1; + } while (budget--); - if (tx_desc) { - ice_xdp_ring_update_tail(xdp_ring); - xsk_tx_release(xdp_ring->xsk_pool); - } + xdp_ring->next_to_clean = ntc; + xdp_ring->next_dd = next_dd; - return budget > 0 && work_done; + return cleared_dds * tx_thresh; } /** - * ice_clean_xdp_tx_buf - Free and unmap XDP Tx buffer - * @xdp_ring: XDP Tx ring - * @tx_buf: Tx buffer to clean + * ice_xmit_pkt - produce a single HW Tx descriptor out of AF_XDP descriptor + * @xdp_ring: XDP ring to produce the HW Tx descriptor on + * @desc: AF_XDP descriptor to pull the DMA address and length from + * @total_bytes: bytes accumulator that will be used for stats update */ -static void -ice_clean_xdp_tx_buf(struct ice_tx_ring *xdp_ring, struct ice_tx_buf *tx_buf) +static void ice_xmit_pkt(struct ice_tx_ring *xdp_ring, struct xdp_desc *desc, + unsigned int *total_bytes) { - xdp_return_frame((struct xdp_frame *)tx_buf->raw_buf); - dma_unmap_single(xdp_ring->dev, dma_unmap_addr(tx_buf, dma), - dma_unmap_len(tx_buf, len), DMA_TO_DEVICE); - dma_unmap_len_set(tx_buf, len, 0); + struct ice_tx_desc *tx_desc; + dma_addr_t dma; + + dma = xsk_buff_raw_get_dma(xdp_ring->xsk_pool, desc->addr); + xsk_buff_raw_dma_sync_for_device(xdp_ring->xsk_pool, dma, desc->len); + + tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_to_use++); + tx_desc->buf_addr = cpu_to_le64(dma); + tx_desc->cmd_type_offset_bsz = ice_build_ctob(ICE_TX_DESC_CMD_EOP, + 0, desc->len, 0); + + *total_bytes += desc->len; } /** - * ice_clean_tx_irq_zc - Completes AF_XDP entries, and cleans XDP entries - * @xdp_ring: XDP Tx ring - * @budget: NAPI budget - * - * Returns true if cleanup/tranmission is done. + * ice_xmit_pkt_batch - produce a batch of HW Tx descriptors out of AF_XDP descriptors + * @xdp_ring: XDP ring to produce the HW Tx descriptors on + * @descs: AF_XDP descriptors to pull the DMA addresses and lengths from + * @total_bytes: bytes accumulator that will be used for stats update */ -bool ice_clean_tx_irq_zc(struct ice_tx_ring *xdp_ring, int budget) +static void ice_xmit_pkt_batch(struct ice_tx_ring *xdp_ring, struct xdp_desc *descs, + unsigned int *total_bytes) { - int total_packets = 0, total_bytes = 0; - s16 ntc = xdp_ring->next_to_clean; + u16 tx_thresh = ICE_RING_QUARTER(xdp_ring); + u16 ntu = xdp_ring->next_to_use; struct ice_tx_desc *tx_desc; - struct ice_tx_buf *tx_buf; - u32 xsk_frames = 0; - bool xmit_done; + u32 i; - tx_desc = ICE_TX_DESC(xdp_ring, ntc); - tx_buf = &xdp_ring->tx_buf[ntc]; - ntc -= xdp_ring->count; + loop_unrolled_for(i = 0; i < PKTS_PER_BATCH; i++) { + dma_addr_t dma; - do { - if (!(tx_desc->cmd_type_offset_bsz & - cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE))) - break; + dma = xsk_buff_raw_get_dma(xdp_ring->xsk_pool, descs[i].addr); + xsk_buff_raw_dma_sync_for_device(xdp_ring->xsk_pool, dma, descs[i].len); - total_bytes += tx_buf->bytecount; - total_packets++; + tx_desc = ICE_TX_DESC(xdp_ring, ntu++); + tx_desc->buf_addr = cpu_to_le64(dma); + tx_desc->cmd_type_offset_bsz = ice_build_ctob(ICE_TX_DESC_CMD_EOP, + 0, descs[i].len, 0); - if (tx_buf->raw_buf) { - ice_clean_xdp_tx_buf(xdp_ring, tx_buf); - tx_buf->raw_buf = NULL; - } else { - xsk_frames++; - } + *total_bytes += descs[i].len; + } - tx_desc->cmd_type_offset_bsz = 0; - tx_buf++; - tx_desc++; - ntc++; + xdp_ring->next_to_use = ntu; - if (unlikely(!ntc)) { - ntc -= xdp_ring->count; - tx_buf = xdp_ring->tx_buf; - tx_desc = ICE_TX_DESC(xdp_ring, 0); - } + if (xdp_ring->next_to_use > xdp_ring->next_rs) { + tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_rs); + tx_desc->cmd_type_offset_bsz |= + cpu_to_le64(ICE_TX_DESC_CMD_RS << ICE_TXD_QW1_CMD_S); + xdp_ring->next_rs += tx_thresh; + } +} - prefetch(tx_desc); +/** + * ice_fill_tx_hw_ring - produce the number of Tx descriptors onto ring + * @xdp_ring: XDP ring to produce the HW Tx descriptors on + * @descs: AF_XDP descriptors to pull the DMA addresses and lengths from + * @nb_pkts: count of packets to be send + * @total_bytes: bytes accumulator that will be used for stats update + */ +static void ice_fill_tx_hw_ring(struct ice_tx_ring *xdp_ring, struct xdp_desc *descs, + u32 nb_pkts, unsigned int *total_bytes) +{ + u16 tx_thresh = ICE_RING_QUARTER(xdp_ring); + u32 batched, leftover, i; + + batched = ALIGN_DOWN(nb_pkts, PKTS_PER_BATCH); + leftover = nb_pkts & (PKTS_PER_BATCH - 1); + for (i = 0; i < batched; i += PKTS_PER_BATCH) + ice_xmit_pkt_batch(xdp_ring, &descs[i], total_bytes); + for (; i < batched + leftover; i++) + ice_xmit_pkt(xdp_ring, &descs[i], total_bytes); + + if (xdp_ring->next_to_use > xdp_ring->next_rs) { + struct ice_tx_desc *tx_desc; + + tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_rs); + tx_desc->cmd_type_offset_bsz |= + cpu_to_le64(ICE_TX_DESC_CMD_RS << ICE_TXD_QW1_CMD_S); + xdp_ring->next_rs += tx_thresh; + } +} - } while (likely(--budget)); +/** + * ice_xmit_zc - take entries from XSK Tx ring and place them onto HW Tx ring + * @xdp_ring: XDP ring to produce the HW Tx descriptors on + * @budget: number of free descriptors on HW Tx ring that can be used + * @napi_budget: amount of descriptors that NAPI allows us to clean + * + * Returns true if there is no more work that needs to be done, false otherwise + */ +bool ice_xmit_zc(struct ice_tx_ring *xdp_ring, u32 budget, int napi_budget) +{ + struct xdp_desc *descs = xdp_ring->xsk_pool->tx_descs; + u16 tx_thresh = ICE_RING_QUARTER(xdp_ring); + u32 nb_pkts, nb_processed = 0; + unsigned int total_bytes = 0; + + if (budget < tx_thresh) + budget += ice_clean_xdp_irq_zc(xdp_ring, napi_budget); + + nb_pkts = xsk_tx_peek_release_desc_batch(xdp_ring->xsk_pool, budget); + if (!nb_pkts) + return true; + + if (xdp_ring->next_to_use + nb_pkts >= xdp_ring->count) { + struct ice_tx_desc *tx_desc; + + nb_processed = xdp_ring->count - xdp_ring->next_to_use; + ice_fill_tx_hw_ring(xdp_ring, descs, nb_processed, &total_bytes); + tx_desc = ICE_TX_DESC(xdp_ring, xdp_ring->next_rs); + tx_desc->cmd_type_offset_bsz |= + cpu_to_le64(ICE_TX_DESC_CMD_RS << ICE_TXD_QW1_CMD_S); + xdp_ring->next_rs = tx_thresh - 1; + xdp_ring->next_to_use = 0; + } - ntc += xdp_ring->count; - xdp_ring->next_to_clean = ntc; + ice_fill_tx_hw_ring(xdp_ring, &descs[nb_processed], nb_pkts - nb_processed, + &total_bytes); - if (xsk_frames) - xsk_tx_completed(xdp_ring->xsk_pool, xsk_frames); + ice_xdp_ring_update_tail(xdp_ring); + ice_update_tx_ring_stats(xdp_ring, nb_pkts, total_bytes); if (xsk_uses_need_wakeup(xdp_ring->xsk_pool)) xsk_set_tx_need_wakeup(xdp_ring->xsk_pool); - ice_update_tx_ring_stats(xdp_ring, total_packets, total_bytes); - xmit_done = ice_xmit_zc(xdp_ring, ICE_DFLT_IRQ_WORK); - - return budget > 0 && xmit_done; + return nb_pkts < budget; } /** diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.h b/drivers/net/ethernet/intel/ice/ice_xsk.h index 4c7bd8e..0cbb579 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.h +++ b/drivers/net/ethernet/intel/ice/ice_xsk.h @@ -6,19 +6,37 @@ #include "ice_txrx.h" #include "ice.h" +#define PKTS_PER_BATCH 8 + +#ifdef __clang__ +#define loop_unrolled_for _Pragma("clang loop unroll_count(8)") for +#elif __GNUC__ >= 4 +#define loop_unrolled_for _Pragma("GCC unroll 8") for +#else +#define loop_unrolled_for for +#endif + struct ice_vsi; #ifdef CONFIG_XDP_SOCKETS int ice_xsk_pool_setup(struct ice_vsi *vsi, struct xsk_buff_pool *pool, u16 qid); int ice_clean_rx_irq_zc(struct ice_rx_ring *rx_ring, int budget); -bool ice_clean_tx_irq_zc(struct ice_tx_ring *xdp_ring, int budget); int ice_xsk_wakeup(struct net_device *netdev, u32 queue_id, u32 flags); bool ice_alloc_rx_bufs_zc(struct ice_rx_ring *rx_ring, u16 count); bool ice_xsk_any_rx_ring_ena(struct ice_vsi *vsi); void ice_xsk_clean_rx_ring(struct ice_rx_ring *rx_ring); void ice_xsk_clean_xdp_ring(struct ice_tx_ring *xdp_ring); +bool ice_xmit_zc(struct ice_tx_ring *xdp_ring, u32 budget, int napi_budget); #else +static inline bool +ice_xmit_zc(struct ice_tx_ring __always_unused *xdp_ring, + u32 __always_unused budget, + int __always_unused napi_budget) +{ + return false; +} + static inline int ice_xsk_pool_setup(struct ice_vsi __always_unused *vsi, struct xsk_buff_pool __always_unused *pool, @@ -35,13 +53,6 @@ ice_clean_rx_irq_zc(struct ice_rx_ring __always_unused *rx_ring, } static inline bool -ice_clean_tx_irq_zc(struct ice_tx_ring __always_unused *xdp_ring, - int __always_unused budget) -{ - return false; -} - -static inline bool ice_alloc_rx_bufs_zc(struct ice_rx_ring __always_unused *rx_ring, u16 __always_unused count) { -- 2.7.4