| Message ID | 20240808183556.386397-4-anthony.l.nguyen@intel.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | igb: Add support for AF_XDP zero-copy | expand |
On Thu, Aug 08, 2024 at 11:35:53AM -0700, Tony Nguyen wrote: > From: Sriram Yagnaraman <sriram.yagnaraman@est.tech> > > Add support for AF_XDP zero-copy receive path. > > When AF_XDP zero-copy is enabled, the rx buffers are allocated from the > xsk buff pool using igb_alloc_rx_buffers_zc. > > Use xsk_pool_get_rx_frame_size to set SRRCTL rx buf size when zero-copy > is enabled. > > Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> > [Kurt: Port to v6.10 and provide napi_id for xdp_rxq_info_reg()] > Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> > Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com> (A Contingent Worker at Intel) > Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> > --- > drivers/net/ethernet/intel/igb/igb.h | 4 + > drivers/net/ethernet/intel/igb/igb_main.c | 95 ++++++-- > drivers/net/ethernet/intel/igb/igb_xsk.c | 261 +++++++++++++++++++++- > 3 files changed, 337 insertions(+), 23 deletions(-) > > diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h > index 053130c01480..4983a6ec718e 100644 > --- a/drivers/net/ethernet/intel/igb/igb.h > +++ b/drivers/net/ethernet/intel/igb/igb.h > @@ -87,6 +87,7 @@ struct igb_adapter; > #define IGB_XDP_CONSUMED BIT(0) > #define IGB_XDP_TX BIT(1) > #define IGB_XDP_REDIR BIT(2) > +#define IGB_XDP_EXIT BIT(3) > > struct vf_data_storage { > unsigned char vf_mac_addresses[ETH_ALEN]; > @@ -832,6 +833,9 @@ struct xsk_buff_pool *igb_xsk_pool(struct igb_adapter *adapter, > int igb_xsk_pool_setup(struct igb_adapter *adapter, > struct xsk_buff_pool *pool, > u16 qid); > +bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, u16 count); > +void igb_clean_rx_ring_zc(struct igb_ring *rx_ring); > +int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, const int budget); > int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags); > > #endif /* _IGB_H_ */ > diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c > index b6f23bbeff71..0b779b2ca9ea 100644 > --- a/drivers/net/ethernet/intel/igb/igb_main.c > +++ b/drivers/net/ethernet/intel/igb/igb_main.c > @@ -472,12 +472,17 @@ static void igb_dump(struct igb_adapter *adapter) > > for (i = 0; i < rx_ring->count; i++) { > const char *next_desc; > - struct igb_rx_buffer *buffer_info; > - buffer_info = &rx_ring->rx_buffer_info[i]; > + dma_addr_t dma = (dma_addr_t)0; > + struct igb_rx_buffer *buffer_info = NULL; > rx_desc = IGB_RX_DESC(rx_ring, i); > u0 = (struct my_u0 *)rx_desc; > staterr = le32_to_cpu(rx_desc->wb.upper.status_error); > > + if (!rx_ring->xsk_pool) { > + buffer_info = &rx_ring->rx_buffer_info[i]; > + dma = buffer_info->dma; > + } > + > if (i == rx_ring->next_to_use) > next_desc = " NTU"; > else if (i == rx_ring->next_to_clean) > @@ -497,11 +502,11 @@ static void igb_dump(struct igb_adapter *adapter) > "R ", i, > le64_to_cpu(u0->a), > le64_to_cpu(u0->b), > - (u64)buffer_info->dma, > + (u64)dma, > next_desc); > > if (netif_msg_pktdata(adapter) && > - buffer_info->dma && buffer_info->page) { > + buffer_info && dma && buffer_info->page) { > print_hex_dump(KERN_INFO, "", > DUMP_PREFIX_ADDRESS, > 16, 1, > @@ -1983,7 +1988,10 @@ static void igb_configure(struct igb_adapter *adapter) > */ > for (i = 0; i < adapter->num_rx_queues; i++) { > struct igb_ring *ring = adapter->rx_ring[i]; > - igb_alloc_rx_buffers(ring, igb_desc_unused(ring)); > + if (ring->xsk_pool) > + igb_alloc_rx_buffers_zc(ring, igb_desc_unused(ring)); > + else > + igb_alloc_rx_buffers(ring, igb_desc_unused(ring)); > } > } > > @@ -3335,7 +3343,8 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) > netdev->priv_flags |= IFF_SUPP_NOFCS; > > netdev->priv_flags |= IFF_UNICAST_FLT; > - netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT; > + netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | > + NETDEV_XDP_ACT_XSK_ZEROCOPY; > > /* MTU range: 68 - 9216 */ > netdev->min_mtu = ETH_MIN_MTU; > @@ -4423,7 +4432,8 @@ int igb_setup_rx_resources(struct igb_ring *rx_ring) > if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq)) > xdp_rxq_info_unreg(&rx_ring->xdp_rxq); > res = xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev, > - rx_ring->queue_index, 0); > + rx_ring->queue_index, > + rx_ring->q_vector->napi.napi_id); > if (res < 0) { > dev_err(dev, "Failed to register xdp_rxq index %u\n", > rx_ring->queue_index); > @@ -4719,12 +4729,17 @@ void igb_setup_srrctl(struct igb_adapter *adapter, struct igb_ring *ring) > struct e1000_hw *hw = &adapter->hw; > int reg_idx = ring->reg_idx; > u32 srrctl = 0; > + u32 buf_size; > > - srrctl = IGB_RX_HDR_LEN << E1000_SRRCTL_BSIZEHDRSIZE_SHIFT; > - if (ring_uses_large_buffer(ring)) > - srrctl |= IGB_RXBUFFER_3072 >> E1000_SRRCTL_BSIZEPKT_SHIFT; > + if (ring->xsk_pool) > + buf_size = xsk_pool_get_rx_frame_size(ring->xsk_pool); > + else if (ring_uses_large_buffer(ring)) > + buf_size = IGB_RXBUFFER_3072; > else > - srrctl |= IGB_RXBUFFER_2048 >> E1000_SRRCTL_BSIZEPKT_SHIFT; > + buf_size = IGB_RXBUFFER_2048; > + > + srrctl = IGB_RX_HDR_LEN << E1000_SRRCTL_BSIZEHDRSIZE_SHIFT; > + srrctl |= buf_size >> E1000_SRRCTL_BSIZEPKT_SHIFT; > srrctl |= E1000_SRRCTL_DESCTYPE_ADV_ONEBUF; > if (hw->mac.type >= e1000_82580) > srrctl |= E1000_SRRCTL_TIMESTAMP; > @@ -4756,9 +4771,17 @@ void igb_configure_rx_ring(struct igb_adapter *adapter, > u32 rxdctl = 0; > > xdp_rxq_info_unreg_mem_model(&ring->xdp_rxq); > - WARN_ON(xdp_rxq_info_reg_mem_model(&ring->xdp_rxq, > - MEM_TYPE_PAGE_SHARED, NULL)); > ring->xsk_pool = igb_xsk_pool(adapter, ring); > + if (ring->xsk_pool) { > + WARN_ON(xdp_rxq_info_reg_mem_model(&ring->xdp_rxq, > + MEM_TYPE_XSK_BUFF_POOL, > + NULL)); > + xsk_pool_set_rxq_info(ring->xsk_pool, &ring->xdp_rxq); > + } else { > + WARN_ON(xdp_rxq_info_reg_mem_model(&ring->xdp_rxq, > + MEM_TYPE_PAGE_SHARED, > + NULL)); > + } > > /* disable the queue */ > wr32(E1000_RXDCTL(reg_idx), 0); > @@ -4785,9 +4808,12 @@ void igb_configure_rx_ring(struct igb_adapter *adapter, > rxdctl |= IGB_RX_HTHRESH << 8; > rxdctl |= IGB_RX_WTHRESH << 16; > > - /* initialize rx_buffer_info */ > - memset(ring->rx_buffer_info, 0, > - sizeof(struct igb_rx_buffer) * ring->count); > + if (ring->xsk_pool) > + memset(ring->rx_buffer_info_zc, 0, > + sizeof(*ring->rx_buffer_info_zc) * ring->count); > + else > + memset(ring->rx_buffer_info, 0, > + sizeof(*ring->rx_buffer_info) * ring->count); ah okay. comment from previous patch is addressed here, thanks. > > /* initialize Rx descriptor 0 */ > rx_desc = IGB_RX_DESC(ring, 0); > @@ -4974,8 +5000,13 @@ void igb_free_rx_resources(struct igb_ring *rx_ring) > > rx_ring->xdp_prog = NULL; > xdp_rxq_info_unreg(&rx_ring->xdp_rxq); > - vfree(rx_ring->rx_buffer_info); > - rx_ring->rx_buffer_info = NULL; > + if (rx_ring->xsk_pool) { > + vfree(rx_ring->rx_buffer_info_zc); > + rx_ring->rx_buffer_info_zc = NULL; > + } else { > + vfree(rx_ring->rx_buffer_info); > + rx_ring->rx_buffer_info = NULL; > + } > > /* if not set, then don't free */ > if (!rx_ring->desc) > @@ -5013,6 +5044,11 @@ void igb_clean_rx_ring(struct igb_ring *rx_ring) > dev_kfree_skb(rx_ring->skb); > rx_ring->skb = NULL; > > + if (rx_ring->xsk_pool) { > + igb_clean_rx_ring_zc(rx_ring); > + goto skip_for_xsk; > + } > + > /* Free all the Rx ring sk_buffs */ > while (i != rx_ring->next_to_alloc) { > struct igb_rx_buffer *buffer_info = &rx_ring->rx_buffer_info[i]; > @@ -5040,6 +5076,7 @@ void igb_clean_rx_ring(struct igb_ring *rx_ring) > i = 0; > } > > +skip_for_xsk: > rx_ring->next_to_alloc = 0; > rx_ring->next_to_clean = 0; > rx_ring->next_to_use = 0; > @@ -8195,7 +8232,9 @@ static int igb_poll(struct napi_struct *napi, int budget) > clean_complete = igb_clean_tx_irq(q_vector, budget); > > if (q_vector->rx.ring) { > - int cleaned = igb_clean_rx_irq(q_vector, budget); > + int cleaned = q_vector->rx.ring->xsk_pool ? best if you would READ_ONCE() here pool and use it for the rest of napi lifetime... > + igb_clean_rx_irq_zc(q_vector, budget) : > + igb_clean_rx_irq(q_vector, budget); > > work_done += cleaned; > if (cleaned >= budget) > @@ -8603,8 +8642,15 @@ struct sk_buff *igb_run_xdp(struct igb_adapter *adapter, > break; > case XDP_REDIRECT: > err = xdp_do_redirect(adapter->netdev, xdp, xdp_prog); We were introducing a ZC variant of handling XDP verdict due to a fact that mostly what happens is the redirect to user space. We observed a reasonable perf improvement from likely()fying XDP_REDIRECT case. > - if (err) > + if (err) { > + if (rx_ring->xsk_pool && > + xsk_uses_need_wakeup(rx_ring->xsk_pool) && > + err == -ENOBUFS) > + result = IGB_XDP_EXIT; > + else > + result = IGB_XDP_CONSUMED; > goto out_failure; > + } > result = IGB_XDP_REDIR; > break; > default: > @@ -8861,12 +8907,14 @@ static void igb_put_rx_buffer(struct igb_ring *rx_ring, > > static int igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget) > { > + unsigned int total_bytes = 0, total_packets = 0; > struct igb_adapter *adapter = q_vector->adapter; > struct igb_ring *rx_ring = q_vector->rx.ring; > - struct sk_buff *skb = rx_ring->skb; > - unsigned int total_bytes = 0, total_packets = 0; > u16 cleaned_count = igb_desc_unused(rx_ring); > + struct sk_buff *skb = rx_ring->skb; > + int cpu = smp_processor_id(); > unsigned int xdp_xmit = 0; > + struct netdev_queue *nq; > struct xdp_buff xdp; > u32 frame_sz = 0; > int rx_buf_pgcnt; > @@ -8994,7 +9042,10 @@ static int igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget) > if (xdp_xmit & IGB_XDP_TX) { > struct igb_ring *tx_ring = igb_xdp_tx_queue_mapping(adapter); > > + nq = txring_txq(tx_ring); > + __netif_tx_lock(nq, cpu); That belongs to a patch where you do: "Always call igb_xdp_ring_update_tail under __netif_tx_lock" > igb_xdp_ring_update_tail(tx_ring); > + __netif_tx_unlock(nq); > } > > u64_stats_update_begin(&rx_ring->rx_syncp); > diff --git a/drivers/net/ethernet/intel/igb/igb_xsk.c b/drivers/net/ethernet/intel/igb/igb_xsk.c > index 925bf97f7caa..66cdc30e9b6e 100644 > --- a/drivers/net/ethernet/intel/igb/igb_xsk.c > +++ b/drivers/net/ethernet/intel/igb/igb_xsk.c > @@ -66,7 +66,10 @@ static void igb_txrx_ring_enable(struct igb_adapter *adapter, u16 qid) > * at least 1 descriptor unused to make sure > * next_to_use != next_to_clean > */ > - igb_alloc_rx_buffers(rx_ring, igb_desc_unused(rx_ring)); > + if (rx_ring->xsk_pool) > + igb_alloc_rx_buffers_zc(rx_ring, igb_desc_unused(rx_ring)); > + else > + igb_alloc_rx_buffers(rx_ring, igb_desc_unused(rx_ring)); > > /* Rx/Tx share the same napi context. */ > napi_enable(&rx_ring->q_vector->napi); > @@ -172,6 +175,262 @@ int igb_xsk_pool_setup(struct igb_adapter *adapter, > igb_xsk_pool_disable(adapter, qid); > } > > +static u16 igb_fill_rx_descs(struct xsk_buff_pool *pool, struct xdp_buff **xdp, > + union e1000_adv_rx_desc *rx_desc, u16 count) > +{ > + dma_addr_t dma; > + u16 buffs; > + int i; > + > + /* nothing to do */ > + if (!count) > + return 0; > + > + buffs = xsk_buff_alloc_batch(pool, xdp, count); > + for (i = 0; i < buffs; i++) { > + dma = xsk_buff_xdp_get_dma(*xdp); > + rx_desc->read.pkt_addr = cpu_to_le64(dma); > + rx_desc->wb.upper.length = 0; > + > + rx_desc++; > + xdp++; > + } > + > + return buffs; > +} > + > +bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, u16 count) > +{ > + u32 nb_buffs_extra = 0, nb_buffs = 0; > + union e1000_adv_rx_desc *rx_desc; > + u16 ntu = rx_ring->next_to_use; > + u16 total_count = count; > + struct xdp_buff **xdp; > + > + rx_desc = IGB_RX_DESC(rx_ring, ntu); > + xdp = &rx_ring->rx_buffer_info_zc[ntu]; > + > + if (ntu + count >= rx_ring->count) { > + nb_buffs_extra = igb_fill_rx_descs(rx_ring->xsk_pool, xdp, > + rx_desc, > + rx_ring->count - ntu); > + if (nb_buffs_extra != rx_ring->count - ntu) { > + ntu += nb_buffs_extra; > + goto exit; > + } > + rx_desc = IGB_RX_DESC(rx_ring, 0); > + xdp = rx_ring->rx_buffer_info_zc; > + ntu = 0; > + count -= nb_buffs_extra; > + } > + > + nb_buffs = igb_fill_rx_descs(rx_ring->xsk_pool, xdp, rx_desc, count); > + ntu += nb_buffs; > + if (ntu == rx_ring->count) > + ntu = 0; > + > + /* clear the length for the next_to_use descriptor */ > + rx_desc = IGB_RX_DESC(rx_ring, ntu); > + rx_desc->wb.upper.length = 0; > + > +exit: > + if (rx_ring->next_to_use != ntu) { > + rx_ring->next_to_use = ntu; > + > + /* Force memory writes to complete before letting h/w > + * know there are new descriptors to fetch. (Only > + * applicable for weak-ordered memory model archs, > + * such as IA-64). > + */ > + wmb(); > + writel(ntu, rx_ring->tail); > + } > + > + return total_count == (nb_buffs + nb_buffs_extra); > +} > + > +void igb_clean_rx_ring_zc(struct igb_ring *rx_ring) > +{ > + u16 ntc = rx_ring->next_to_clean; > + u16 ntu = rx_ring->next_to_use; > + > + while (ntc != ntu) { > + struct xdp_buff *xdp = rx_ring->rx_buffer_info_zc[ntc]; > + > + xsk_buff_free(xdp); > + ntc++; > + if (ntc >= rx_ring->count) > + ntc = 0; > + } > +} > + > +static struct sk_buff *igb_construct_skb_zc(struct igb_ring *rx_ring, > + struct xdp_buff *xdp, > + ktime_t timestamp) > +{ > + unsigned int totalsize = xdp->data_end - xdp->data_meta; > + unsigned int metasize = xdp->data - xdp->data_meta; > + struct sk_buff *skb; > + > + net_prefetch(xdp->data_meta); > + > + /* allocate a skb to store the frags */ > + skb = napi_alloc_skb(&rx_ring->q_vector->napi, totalsize); > + if (unlikely(!skb)) > + return NULL; > + > + if (timestamp) > + skb_hwtstamps(skb)->hwtstamp = timestamp; > + > + memcpy(__skb_put(skb, totalsize), xdp->data_meta, > + ALIGN(totalsize, sizeof(long))); > + > + if (metasize) { > + skb_metadata_set(skb, metasize); > + __skb_pull(skb, metasize); > + } > + > + return skb; > +} > + > +static void igb_update_ntc(struct igb_ring *rx_ring) > +{ > + u32 ntc = rx_ring->next_to_clean + 1; > + > + /* fetch, update, and store next to clean */ > + ntc = (ntc < rx_ring->count) ? ntc : 0; > + rx_ring->next_to_clean = ntc; That is suboptimal. You don't have update the ring's member per each procesed descriptor. What you can do is to work on a local ntc and update it to ring at the end of napi's Rx side. Even if you would insist on doing the current way then I would expect that you would use this helper in igb_is_non_eop() as this is duplicated code. > + > + prefetch(IGB_RX_DESC(rx_ring, ntc)); > +} > + > +int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, const int budget) > +{ > + struct igb_adapter *adapter = q_vector->adapter; > + unsigned int total_bytes = 0, total_packets = 0; > + struct igb_ring *rx_ring = q_vector->rx.ring; > + int cpu = smp_processor_id(); > + unsigned int xdp_xmit = 0; > + struct netdev_queue *nq; > + bool failure = false; > + u16 entries_to_alloc; > + struct sk_buff *skb; > + > + while (likely(total_packets < budget)) { > + union e1000_adv_rx_desc *rx_desc; > + struct xdp_buff *xdp; > + ktime_t timestamp = 0; minor: RCT > + unsigned int size; > + > + rx_desc = IGB_RX_DESC(rx_ring, rx_ring->next_to_clean); > + size = le16_to_cpu(rx_desc->wb.upper.length); > + if (!size) > + break; > + > + /* This memory barrier is needed to keep us from reading > + * any other fields out of the rx_desc until we know the > + * descriptor has been written back > + */ > + dma_rmb(); > + > + xdp = rx_ring->rx_buffer_info_zc[rx_ring->next_to_clean]; > + xsk_buff_set_size(xdp, size); > + xsk_buff_dma_sync_for_cpu(xdp); > + > + /* pull rx packet timestamp if available and valid */ > + if (igb_test_staterr(rx_desc, E1000_RXDADV_STAT_TSIP)) { > + int ts_hdr_len; > + > + ts_hdr_len = igb_ptp_rx_pktstamp(rx_ring->q_vector, > + xdp->data, > + ×tamp); > + > + xdp->data += ts_hdr_len; > + xdp->data_meta += ts_hdr_len; > + size -= ts_hdr_len; > + } > + > + skb = igb_run_xdp(adapter, rx_ring, xdp); > + > + if (IS_ERR(skb)) { > + unsigned int xdp_res = -PTR_ERR(skb); > + > + if (likely(xdp_res & (IGB_XDP_TX | IGB_XDP_REDIR))) { > + xdp_xmit |= xdp_res; > + } else if (xdp_res == IGB_XDP_EXIT) { > + failure = true; > + break; > + } else if (xdp_res == IGB_XDP_CONSUMED) { > + xsk_buff_free(xdp); > + } > + > + total_packets++; > + total_bytes += size; > + > + igb_update_ntc(rx_ring); > + continue; > + } > + > + skb = igb_construct_skb_zc(rx_ring, xdp, timestamp); > + > + /* exit if we failed to retrieve a buffer */ > + if (!skb) { > + rx_ring->rx_stats.alloc_failed++; > + break; > + } > + > + xsk_buff_free(xdp); > + igb_update_ntc(rx_ring); > + > + if (eth_skb_pad(skb)) > + continue; > + > + /* probably a little skewed due to removing CRC */ > + total_bytes += skb->len; > + > + /* populate checksum, timestamp, VLAN, and protocol */ > + igb_process_skb_fields(rx_ring, rx_desc, skb); > + > + napi_gro_receive(&q_vector->napi, skb); > + > + /* update budget accounting */ > + total_packets++; > + } > + > + if (xdp_xmit & IGB_XDP_REDIR) > + xdp_do_flush(); > + > + if (xdp_xmit & IGB_XDP_TX) { > + struct igb_ring *tx_ring = igb_xdp_tx_queue_mapping(adapter); pull this out to common function and use this in igb_clean_rx_irq() ? > + > + nq = txring_txq(tx_ring); > + __netif_tx_lock(nq, cpu); > + igb_xdp_ring_update_tail(tx_ring); > + __netif_tx_unlock(nq); > + } > + > + u64_stats_update_begin(&rx_ring->rx_syncp); > + rx_ring->rx_stats.packets += total_packets; > + rx_ring->rx_stats.bytes += total_bytes; > + u64_stats_update_end(&rx_ring->rx_syncp); > + q_vector->rx.total_packets += total_packets; > + q_vector->rx.total_bytes += total_bytes; ... same here :) > + > + entries_to_alloc = igb_desc_unused(rx_ring); > + if (entries_to_alloc >= IGB_RX_BUFFER_WRITE) > + failure |= !igb_alloc_rx_buffers_zc(rx_ring, entries_to_alloc); > + > + if (xsk_uses_need_wakeup(rx_ring->xsk_pool)) { > + if (failure || rx_ring->next_to_clean == rx_ring->next_to_use) > + xsk_set_rx_need_wakeup(rx_ring->xsk_pool); > + else > + xsk_clear_rx_need_wakeup(rx_ring->xsk_pool); > + > + return (int)total_packets; > + } > + return failure ? budget : (int)total_packets; > +} > + > int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags) > { > struct igb_adapter *adapter = netdev_priv(dev); > -- > 2.42.0 >
On Sat, Aug 10, 2024 at 03:55:10PM +0200, Maciej Fijalkowski wrote: > On Thu, Aug 08, 2024 at 11:35:53AM -0700, Tony Nguyen wrote: > > From: Sriram Yagnaraman <sriram.yagnaraman@est.tech> > > > > Add support for AF_XDP zero-copy receive path. > > > > When AF_XDP zero-copy is enabled, the rx buffers are allocated from the > > xsk buff pool using igb_alloc_rx_buffers_zc. > > > > Use xsk_pool_get_rx_frame_size to set SRRCTL rx buf size when zero-copy > > is enabled. > > > > Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> > > [Kurt: Port to v6.10 and provide napi_id for xdp_rxq_info_reg()] > > Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> > > Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com> (A Contingent Worker at Intel) > > Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> > > --- > > netdev->priv_flags |= IFF_UNICAST_FLT; > > - netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT; > > + netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | > > + NETDEV_XDP_ACT_XSK_ZEROCOPY; > > Also please set this on last patch as this opens us to a state where AF_XDP ZC is enabled but there is no Tx ZC yet.
>> case XDP_REDIRECT: >> err = xdp_do_redirect(adapter->netdev, xdp, xdp_prog); > > We were introducing a ZC variant of handling XDP verdict due to a fact > that mostly what happens is the redirect to user space. We observed a > reasonable perf improvement from likely()fying XDP_REDIRECT case. Indeed, I can observe an improvement too. I've introduced igb_run_xdp_zc() which takes care of that optimization. Also it takes a pointer to the (read once) xsk_pool to address the other comment. Thanks, Kurt
On Wed, Aug 14, 2024 at 10:29:29AM +0200, Kurt Kanzenbach wrote: > >> case XDP_REDIRECT: > >> err = xdp_do_redirect(adapter->netdev, xdp, xdp_prog); > > > > We were introducing a ZC variant of handling XDP verdict due to a fact > > that mostly what happens is the redirect to user space. We observed a > > reasonable perf improvement from likely()fying XDP_REDIRECT case. > > Indeed, I can observe an improvement too. > > I've introduced igb_run_xdp_zc() which takes care of that > optimization. Also it takes a pointer to the (read once) xsk_pool to > address the other comment. Nice, thanks! > > Thanks, > Kurt
diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h index 053130c01480..4983a6ec718e 100644 --- a/drivers/net/ethernet/intel/igb/igb.h +++ b/drivers/net/ethernet/intel/igb/igb.h @@ -87,6 +87,7 @@ struct igb_adapter; #define IGB_XDP_CONSUMED BIT(0) #define IGB_XDP_TX BIT(1) #define IGB_XDP_REDIR BIT(2) +#define IGB_XDP_EXIT BIT(3) struct vf_data_storage { unsigned char vf_mac_addresses[ETH_ALEN]; @@ -832,6 +833,9 @@ struct xsk_buff_pool *igb_xsk_pool(struct igb_adapter *adapter, int igb_xsk_pool_setup(struct igb_adapter *adapter, struct xsk_buff_pool *pool, u16 qid); +bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, u16 count); +void igb_clean_rx_ring_zc(struct igb_ring *rx_ring); +int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, const int budget); int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags); #endif /* _IGB_H_ */ diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index b6f23bbeff71..0b779b2ca9ea 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -472,12 +472,17 @@ static void igb_dump(struct igb_adapter *adapter) for (i = 0; i < rx_ring->count; i++) { const char *next_desc; - struct igb_rx_buffer *buffer_info; - buffer_info = &rx_ring->rx_buffer_info[i]; + dma_addr_t dma = (dma_addr_t)0; + struct igb_rx_buffer *buffer_info = NULL; rx_desc = IGB_RX_DESC(rx_ring, i); u0 = (struct my_u0 *)rx_desc; staterr = le32_to_cpu(rx_desc->wb.upper.status_error); + if (!rx_ring->xsk_pool) { + buffer_info = &rx_ring->rx_buffer_info[i]; + dma = buffer_info->dma; + } + if (i == rx_ring->next_to_use) next_desc = " NTU"; else if (i == rx_ring->next_to_clean) @@ -497,11 +502,11 @@ static void igb_dump(struct igb_adapter *adapter) "R ", i, le64_to_cpu(u0->a), le64_to_cpu(u0->b), - (u64)buffer_info->dma, + (u64)dma, next_desc); if (netif_msg_pktdata(adapter) && - buffer_info->dma && buffer_info->page) { + buffer_info && dma && buffer_info->page) { print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 1, @@ -1983,7 +1988,10 @@ static void igb_configure(struct igb_adapter *adapter) */ for (i = 0; i < adapter->num_rx_queues; i++) { struct igb_ring *ring = adapter->rx_ring[i]; - igb_alloc_rx_buffers(ring, igb_desc_unused(ring)); + if (ring->xsk_pool) + igb_alloc_rx_buffers_zc(ring, igb_desc_unused(ring)); + else + igb_alloc_rx_buffers(ring, igb_desc_unused(ring)); } } @@ -3335,7 +3343,8 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) netdev->priv_flags |= IFF_SUPP_NOFCS; netdev->priv_flags |= IFF_UNICAST_FLT; - netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT; + netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | + NETDEV_XDP_ACT_XSK_ZEROCOPY; /* MTU range: 68 - 9216 */ netdev->min_mtu = ETH_MIN_MTU; @@ -4423,7 +4432,8 @@ int igb_setup_rx_resources(struct igb_ring *rx_ring) if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq)) xdp_rxq_info_unreg(&rx_ring->xdp_rxq); res = xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev, - rx_ring->queue_index, 0); + rx_ring->queue_index, + rx_ring->q_vector->napi.napi_id); if (res < 0) { dev_err(dev, "Failed to register xdp_rxq index %u\n", rx_ring->queue_index); @@ -4719,12 +4729,17 @@ void igb_setup_srrctl(struct igb_adapter *adapter, struct igb_ring *ring) struct e1000_hw *hw = &adapter->hw; int reg_idx = ring->reg_idx; u32 srrctl = 0; + u32 buf_size; - srrctl = IGB_RX_HDR_LEN << E1000_SRRCTL_BSIZEHDRSIZE_SHIFT; - if (ring_uses_large_buffer(ring)) - srrctl |= IGB_RXBUFFER_3072 >> E1000_SRRCTL_BSIZEPKT_SHIFT; + if (ring->xsk_pool) + buf_size = xsk_pool_get_rx_frame_size(ring->xsk_pool); + else if (ring_uses_large_buffer(ring)) + buf_size = IGB_RXBUFFER_3072; else - srrctl |= IGB_RXBUFFER_2048 >> E1000_SRRCTL_BSIZEPKT_SHIFT; + buf_size = IGB_RXBUFFER_2048; + + srrctl = IGB_RX_HDR_LEN << E1000_SRRCTL_BSIZEHDRSIZE_SHIFT; + srrctl |= buf_size >> E1000_SRRCTL_BSIZEPKT_SHIFT; srrctl |= E1000_SRRCTL_DESCTYPE_ADV_ONEBUF; if (hw->mac.type >= e1000_82580) srrctl |= E1000_SRRCTL_TIMESTAMP; @@ -4756,9 +4771,17 @@ void igb_configure_rx_ring(struct igb_adapter *adapter, u32 rxdctl = 0; xdp_rxq_info_unreg_mem_model(&ring->xdp_rxq); - WARN_ON(xdp_rxq_info_reg_mem_model(&ring->xdp_rxq, - MEM_TYPE_PAGE_SHARED, NULL)); ring->xsk_pool = igb_xsk_pool(adapter, ring); + if (ring->xsk_pool) { + WARN_ON(xdp_rxq_info_reg_mem_model(&ring->xdp_rxq, + MEM_TYPE_XSK_BUFF_POOL, + NULL)); + xsk_pool_set_rxq_info(ring->xsk_pool, &ring->xdp_rxq); + } else { + WARN_ON(xdp_rxq_info_reg_mem_model(&ring->xdp_rxq, + MEM_TYPE_PAGE_SHARED, + NULL)); + } /* disable the queue */ wr32(E1000_RXDCTL(reg_idx), 0); @@ -4785,9 +4808,12 @@ void igb_configure_rx_ring(struct igb_adapter *adapter, rxdctl |= IGB_RX_HTHRESH << 8; rxdctl |= IGB_RX_WTHRESH << 16; - /* initialize rx_buffer_info */ - memset(ring->rx_buffer_info, 0, - sizeof(struct igb_rx_buffer) * ring->count); + if (ring->xsk_pool) + memset(ring->rx_buffer_info_zc, 0, + sizeof(*ring->rx_buffer_info_zc) * ring->count); + else + memset(ring->rx_buffer_info, 0, + sizeof(*ring->rx_buffer_info) * ring->count); /* initialize Rx descriptor 0 */ rx_desc = IGB_RX_DESC(ring, 0); @@ -4974,8 +5000,13 @@ void igb_free_rx_resources(struct igb_ring *rx_ring) rx_ring->xdp_prog = NULL; xdp_rxq_info_unreg(&rx_ring->xdp_rxq); - vfree(rx_ring->rx_buffer_info); - rx_ring->rx_buffer_info = NULL; + if (rx_ring->xsk_pool) { + vfree(rx_ring->rx_buffer_info_zc); + rx_ring->rx_buffer_info_zc = NULL; + } else { + vfree(rx_ring->rx_buffer_info); + rx_ring->rx_buffer_info = NULL; + } /* if not set, then don't free */ if (!rx_ring->desc) @@ -5013,6 +5044,11 @@ void igb_clean_rx_ring(struct igb_ring *rx_ring) dev_kfree_skb(rx_ring->skb); rx_ring->skb = NULL; + if (rx_ring->xsk_pool) { + igb_clean_rx_ring_zc(rx_ring); + goto skip_for_xsk; + } + /* Free all the Rx ring sk_buffs */ while (i != rx_ring->next_to_alloc) { struct igb_rx_buffer *buffer_info = &rx_ring->rx_buffer_info[i]; @@ -5040,6 +5076,7 @@ void igb_clean_rx_ring(struct igb_ring *rx_ring) i = 0; } +skip_for_xsk: rx_ring->next_to_alloc = 0; rx_ring->next_to_clean = 0; rx_ring->next_to_use = 0; @@ -8195,7 +8232,9 @@ static int igb_poll(struct napi_struct *napi, int budget) clean_complete = igb_clean_tx_irq(q_vector, budget); if (q_vector->rx.ring) { - int cleaned = igb_clean_rx_irq(q_vector, budget); + int cleaned = q_vector->rx.ring->xsk_pool ? + igb_clean_rx_irq_zc(q_vector, budget) : + igb_clean_rx_irq(q_vector, budget); work_done += cleaned; if (cleaned >= budget) @@ -8603,8 +8642,15 @@ struct sk_buff *igb_run_xdp(struct igb_adapter *adapter, break; case XDP_REDIRECT: err = xdp_do_redirect(adapter->netdev, xdp, xdp_prog); - if (err) + if (err) { + if (rx_ring->xsk_pool && + xsk_uses_need_wakeup(rx_ring->xsk_pool) && + err == -ENOBUFS) + result = IGB_XDP_EXIT; + else + result = IGB_XDP_CONSUMED; goto out_failure; + } result = IGB_XDP_REDIR; break; default: @@ -8861,12 +8907,14 @@ static void igb_put_rx_buffer(struct igb_ring *rx_ring, static int igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget) { + unsigned int total_bytes = 0, total_packets = 0; struct igb_adapter *adapter = q_vector->adapter; struct igb_ring *rx_ring = q_vector->rx.ring; - struct sk_buff *skb = rx_ring->skb; - unsigned int total_bytes = 0, total_packets = 0; u16 cleaned_count = igb_desc_unused(rx_ring); + struct sk_buff *skb = rx_ring->skb; + int cpu = smp_processor_id(); unsigned int xdp_xmit = 0; + struct netdev_queue *nq; struct xdp_buff xdp; u32 frame_sz = 0; int rx_buf_pgcnt; @@ -8994,7 +9042,10 @@ static int igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget) if (xdp_xmit & IGB_XDP_TX) { struct igb_ring *tx_ring = igb_xdp_tx_queue_mapping(adapter); + nq = txring_txq(tx_ring); + __netif_tx_lock(nq, cpu); igb_xdp_ring_update_tail(tx_ring); + __netif_tx_unlock(nq); } u64_stats_update_begin(&rx_ring->rx_syncp); diff --git a/drivers/net/ethernet/intel/igb/igb_xsk.c b/drivers/net/ethernet/intel/igb/igb_xsk.c index 925bf97f7caa..66cdc30e9b6e 100644 --- a/drivers/net/ethernet/intel/igb/igb_xsk.c +++ b/drivers/net/ethernet/intel/igb/igb_xsk.c @@ -66,7 +66,10 @@ static void igb_txrx_ring_enable(struct igb_adapter *adapter, u16 qid) * at least 1 descriptor unused to make sure * next_to_use != next_to_clean */ - igb_alloc_rx_buffers(rx_ring, igb_desc_unused(rx_ring)); + if (rx_ring->xsk_pool) + igb_alloc_rx_buffers_zc(rx_ring, igb_desc_unused(rx_ring)); + else + igb_alloc_rx_buffers(rx_ring, igb_desc_unused(rx_ring)); /* Rx/Tx share the same napi context. */ napi_enable(&rx_ring->q_vector->napi); @@ -172,6 +175,262 @@ int igb_xsk_pool_setup(struct igb_adapter *adapter, igb_xsk_pool_disable(adapter, qid); } +static u16 igb_fill_rx_descs(struct xsk_buff_pool *pool, struct xdp_buff **xdp, + union e1000_adv_rx_desc *rx_desc, u16 count) +{ + dma_addr_t dma; + u16 buffs; + int i; + + /* nothing to do */ + if (!count) + return 0; + + buffs = xsk_buff_alloc_batch(pool, xdp, count); + for (i = 0; i < buffs; i++) { + dma = xsk_buff_xdp_get_dma(*xdp); + rx_desc->read.pkt_addr = cpu_to_le64(dma); + rx_desc->wb.upper.length = 0; + + rx_desc++; + xdp++; + } + + return buffs; +} + +bool igb_alloc_rx_buffers_zc(struct igb_ring *rx_ring, u16 count) +{ + u32 nb_buffs_extra = 0, nb_buffs = 0; + union e1000_adv_rx_desc *rx_desc; + u16 ntu = rx_ring->next_to_use; + u16 total_count = count; + struct xdp_buff **xdp; + + rx_desc = IGB_RX_DESC(rx_ring, ntu); + xdp = &rx_ring->rx_buffer_info_zc[ntu]; + + if (ntu + count >= rx_ring->count) { + nb_buffs_extra = igb_fill_rx_descs(rx_ring->xsk_pool, xdp, + rx_desc, + rx_ring->count - ntu); + if (nb_buffs_extra != rx_ring->count - ntu) { + ntu += nb_buffs_extra; + goto exit; + } + rx_desc = IGB_RX_DESC(rx_ring, 0); + xdp = rx_ring->rx_buffer_info_zc; + ntu = 0; + count -= nb_buffs_extra; + } + + nb_buffs = igb_fill_rx_descs(rx_ring->xsk_pool, xdp, rx_desc, count); + ntu += nb_buffs; + if (ntu == rx_ring->count) + ntu = 0; + + /* clear the length for the next_to_use descriptor */ + rx_desc = IGB_RX_DESC(rx_ring, ntu); + rx_desc->wb.upper.length = 0; + +exit: + if (rx_ring->next_to_use != ntu) { + rx_ring->next_to_use = ntu; + + /* Force memory writes to complete before letting h/w + * know there are new descriptors to fetch. (Only + * applicable for weak-ordered memory model archs, + * such as IA-64). + */ + wmb(); + writel(ntu, rx_ring->tail); + } + + return total_count == (nb_buffs + nb_buffs_extra); +} + +void igb_clean_rx_ring_zc(struct igb_ring *rx_ring) +{ + u16 ntc = rx_ring->next_to_clean; + u16 ntu = rx_ring->next_to_use; + + while (ntc != ntu) { + struct xdp_buff *xdp = rx_ring->rx_buffer_info_zc[ntc]; + + xsk_buff_free(xdp); + ntc++; + if (ntc >= rx_ring->count) + ntc = 0; + } +} + +static struct sk_buff *igb_construct_skb_zc(struct igb_ring *rx_ring, + struct xdp_buff *xdp, + ktime_t timestamp) +{ + unsigned int totalsize = xdp->data_end - xdp->data_meta; + unsigned int metasize = xdp->data - xdp->data_meta; + struct sk_buff *skb; + + net_prefetch(xdp->data_meta); + + /* allocate a skb to store the frags */ + skb = napi_alloc_skb(&rx_ring->q_vector->napi, totalsize); + if (unlikely(!skb)) + return NULL; + + if (timestamp) + skb_hwtstamps(skb)->hwtstamp = timestamp; + + memcpy(__skb_put(skb, totalsize), xdp->data_meta, + ALIGN(totalsize, sizeof(long))); + + if (metasize) { + skb_metadata_set(skb, metasize); + __skb_pull(skb, metasize); + } + + return skb; +} + +static void igb_update_ntc(struct igb_ring *rx_ring) +{ + u32 ntc = rx_ring->next_to_clean + 1; + + /* fetch, update, and store next to clean */ + ntc = (ntc < rx_ring->count) ? ntc : 0; + rx_ring->next_to_clean = ntc; + + prefetch(IGB_RX_DESC(rx_ring, ntc)); +} + +int igb_clean_rx_irq_zc(struct igb_q_vector *q_vector, const int budget) +{ + struct igb_adapter *adapter = q_vector->adapter; + unsigned int total_bytes = 0, total_packets = 0; + struct igb_ring *rx_ring = q_vector->rx.ring; + int cpu = smp_processor_id(); + unsigned int xdp_xmit = 0; + struct netdev_queue *nq; + bool failure = false; + u16 entries_to_alloc; + struct sk_buff *skb; + + while (likely(total_packets < budget)) { + union e1000_adv_rx_desc *rx_desc; + struct xdp_buff *xdp; + ktime_t timestamp = 0; + unsigned int size; + + rx_desc = IGB_RX_DESC(rx_ring, rx_ring->next_to_clean); + size = le16_to_cpu(rx_desc->wb.upper.length); + if (!size) + break; + + /* This memory barrier is needed to keep us from reading + * any other fields out of the rx_desc until we know the + * descriptor has been written back + */ + dma_rmb(); + + xdp = rx_ring->rx_buffer_info_zc[rx_ring->next_to_clean]; + xsk_buff_set_size(xdp, size); + xsk_buff_dma_sync_for_cpu(xdp); + + /* pull rx packet timestamp if available and valid */ + if (igb_test_staterr(rx_desc, E1000_RXDADV_STAT_TSIP)) { + int ts_hdr_len; + + ts_hdr_len = igb_ptp_rx_pktstamp(rx_ring->q_vector, + xdp->data, + ×tamp); + + xdp->data += ts_hdr_len; + xdp->data_meta += ts_hdr_len; + size -= ts_hdr_len; + } + + skb = igb_run_xdp(adapter, rx_ring, xdp); + + if (IS_ERR(skb)) { + unsigned int xdp_res = -PTR_ERR(skb); + + if (likely(xdp_res & (IGB_XDP_TX | IGB_XDP_REDIR))) { + xdp_xmit |= xdp_res; + } else if (xdp_res == IGB_XDP_EXIT) { + failure = true; + break; + } else if (xdp_res == IGB_XDP_CONSUMED) { + xsk_buff_free(xdp); + } + + total_packets++; + total_bytes += size; + + igb_update_ntc(rx_ring); + continue; + } + + skb = igb_construct_skb_zc(rx_ring, xdp, timestamp); + + /* exit if we failed to retrieve a buffer */ + if (!skb) { + rx_ring->rx_stats.alloc_failed++; + break; + } + + xsk_buff_free(xdp); + igb_update_ntc(rx_ring); + + if (eth_skb_pad(skb)) + continue; + + /* probably a little skewed due to removing CRC */ + total_bytes += skb->len; + + /* populate checksum, timestamp, VLAN, and protocol */ + igb_process_skb_fields(rx_ring, rx_desc, skb); + + napi_gro_receive(&q_vector->napi, skb); + + /* update budget accounting */ + total_packets++; + } + + if (xdp_xmit & IGB_XDP_REDIR) + xdp_do_flush(); + + if (xdp_xmit & IGB_XDP_TX) { + struct igb_ring *tx_ring = igb_xdp_tx_queue_mapping(adapter); + + nq = txring_txq(tx_ring); + __netif_tx_lock(nq, cpu); + igb_xdp_ring_update_tail(tx_ring); + __netif_tx_unlock(nq); + } + + u64_stats_update_begin(&rx_ring->rx_syncp); + rx_ring->rx_stats.packets += total_packets; + rx_ring->rx_stats.bytes += total_bytes; + u64_stats_update_end(&rx_ring->rx_syncp); + q_vector->rx.total_packets += total_packets; + q_vector->rx.total_bytes += total_bytes; + + entries_to_alloc = igb_desc_unused(rx_ring); + if (entries_to_alloc >= IGB_RX_BUFFER_WRITE) + failure |= !igb_alloc_rx_buffers_zc(rx_ring, entries_to_alloc); + + if (xsk_uses_need_wakeup(rx_ring->xsk_pool)) { + if (failure || rx_ring->next_to_clean == rx_ring->next_to_use) + xsk_set_rx_need_wakeup(rx_ring->xsk_pool); + else + xsk_clear_rx_need_wakeup(rx_ring->xsk_pool); + + return (int)total_packets; + } + return failure ? budget : (int)total_packets; +} + int igb_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags) { struct igb_adapter *adapter = netdev_priv(dev);