From: Viacheslav Ovsiienko Date: Fri, 16 Oct 2020 16:44:35 +0000 (+0000) Subject: ethdev: introduce Rx buffer split X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=4ff702b5dfa94fbc5d8fd8561277f106dafe1266;p=dpdk.git ethdev: introduce Rx buffer split The DPDK datapath in the transmit direction is very flexible. An application can build the multi-segment packet and manages almost all data aspects - the memory pools where segments are allocated from, the segment lengths, the memory attributes like external buffers, registered for DMA, etc. In the receiving direction, the datapath is much less flexible, an application can only specify the memory pool to configure the receiving queue and nothing more. In order to extend receiving datapath capabilities it is proposed to add the way to provide extended information how to split the packets being received. The new offload flag RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT in device capabilities is introduced to present the way for PMD to report to application about supporting Rx packet split to configurable segments. Prior invoking the rte_eth_rx_queue_setup() routine application should check RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT flag. The following structure is introduced to specify the Rx packet segment for RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT offload: struct rte_eth_rxseg_split { struct rte_mempool *mp; /* memory pools to allocate segment from */ uint16_t length; /* segment maximal data length, configures "split point" */ uint16_t offset; /* data offset from beginning of mbuf data buffer */ uint32_t reserved; /* reserved field */ }; The segment descriptions are added to the rte_eth_rxconf structure: rx_seg - pointer the array of segment descriptions, each element describes the memory pool, maximal data length, initial data offset from the beginning of data buffer in mbuf. This array allows to specify the different settings for each segment in individual fashion. rx_nseg - number of elements in the array If the extended segment descriptions is provided with these new fields the mp parameter of the rte_eth_rx_queue_setup must be specified as NULL to avoid ambiguity. There are two options to specify Rx buffer configuration: - mp is not NULL, rrx_conf.rx_nseg is zero, it is compatible configuration, follows existing implementation, provides the single pool and no description for segment sizes and offsets. - mp is NULL, rx_conf.rx_seg is not NULL, rx_conf.rx_nseg is not zero, it provides the extended configuration, individually for each segment. f the Rx queue is configured with new settings the packets being received will be split into multiple segments pushed to the mbufs with specified attributes. The PMD will split the received packets into multiple segments according to the specification in the description array. For example, let's suppose we configured the Rx queue with the following segments: seg0 - pool0, len0=14B, off0=2 seg1 - pool1, len1=20B, off1=128B seg2 - pool2, len2=20B, off2=0B seg3 - pool3, len3=512B, off3=0B The packet 46 bytes long will look like the following: seg0 - 14B long @ RTE_PKTMBUF_HEADROOM + 2 in mbuf from pool0 seg1 - 20B long @ 128 in mbuf from pool1 seg2 - 12B long @ 0 in mbuf from pool2 The packet 1500 bytes long will look like the following: seg0 - 14B @ RTE_PKTMBUF_HEADROOM + 2 in mbuf from pool0 seg1 - 20B @ 128 in mbuf from pool1 seg2 - 20B @ 0 in mbuf from pool2 seg3 - 512B @ 0 in mbuf from pool3 seg4 - 512B @ 0 in mbuf from pool3 seg5 - 422B @ 0 in mbuf from pool3 The offload RTE_ETH_RX_OFFLOAD_SCATTER must be present and configured to support new buffer split feature (if rx_nseg is greater than one). The split limitations imposed by underlying PMD is reported in the new introduced rte_eth_dev_info->rx_seg_capa field. The new approach would allow splitting the ingress packets into multiple parts pushed to the memory with different attributes. For example, the packet headers can be pushed to the embedded data buffers within mbufs and the application data into the external buffers attached to mbufs allocated from the different memory pools. The memory attributes for the split parts may differ either - for example the application data may be pushed into the external memory located on the dedicated physical device, say GPU or NVMe. This would improve the DPDK receiving datapath flexibility with preserving compatibility with existing API. Signed-off-by: Viacheslav Ovsiienko Acked-by: Ajit Khaparde Acked-by: Jerin Jacob Reviewed-by: Andrew Rybchenko Acked-by: Thomas Monjalon --- diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst index dd8c9555b0..16e00b8f64 100644 --- a/doc/guides/nics/features.rst +++ b/doc/guides/nics/features.rst @@ -185,6 +185,20 @@ Supports receiving segmented mbufs. * **[related] eth_dev_ops**: ``rx_pkt_burst``. +.. _nic_features_buffer_split: + +Buffer Split on Rx +------------------ + +Scatters the packets being received on specified boundaries to segmented mbufs. + +* **[uses] rte_eth_rxconf,rte_eth_rxmode**: ``offloads:RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT``. +* **[uses] rte_eth_rxconf**: ``rx_conf.rx_seg, rx_conf.rx_nseg``. +* **[implements] datapath**: ``Buffer Split functionality``. +* **[provides] rte_eth_dev_info**: ``rx_offload_capa:RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT``. +* **[related] API**: ``rte_eth_rx_queue_setup()``. + + .. _nic_features_lro: LRO diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst index 3bcc4ffc6f..6b191aaf69 100644 --- a/doc/guides/rel_notes/deprecation.rst +++ b/doc/guides/rel_notes/deprecation.rst @@ -138,11 +138,6 @@ Deprecation Notices In 19.11 PMDs will still update the field even when the offload is not enabled. -* ethdev: Add new fields to ``rte_eth_rxconf`` to configure the receiving - queues to split ingress packets into multiple segments according to the - specified lengths into the buffers allocated from the specified - memory pools. The backward compatibility to existing API is preserved. - * ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done`` will be removed in 21.11. Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status`` diff --git a/doc/guides/rel_notes/release_20_11.rst b/doc/guides/rel_notes/release_20_11.rst index 101f72daa0..f0337a16ff 100644 --- a/doc/guides/rel_notes/release_20_11.rst +++ b/doc/guides/rel_notes/release_20_11.rst @@ -83,6 +83,12 @@ New Features * Added optimized implementations of CRC32-Ethernet and CRC16-CCITT using the AVX512 and VPCLMULQDQ instruction sets. +* **Introduced extended buffer description for receiving.** + + Added the extended Rx buffer description for Rx queue setup routine + providing the individual settings for each Rx segment with maximal size, + buffer offset and memory pool to allocate data buffers from. + * **Added the FEC API, for a generic FEC query and config.** Added the FEC API which provides functions for query FEC capabilities and @@ -539,6 +545,9 @@ ABI Changes Applications should use the new values for identification of existing extensions in the packet header. + * Added fields ``rx_seg`` and ``rx_nseg`` to ``rte_eth_rxconf`` structure + to provide extended description of the receiving buffer. + * ``struct rte_eth_hairpin_conf`` has two new members: * ``uint32_t tx_explicit:1;`` diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c index 8ffc2ca1c7..38f249ab7a 100644 --- a/lib/librte_ethdev/rte_ethdev.c +++ b/lib/librte_ethdev/rte_ethdev.c @@ -104,6 +104,9 @@ static const struct rte_eth_xstats_name_off rte_txq_stats_strings[] = { #define RTE_RX_OFFLOAD_BIT2STR(_name) \ { DEV_RX_OFFLOAD_##_name, #_name } +#define RTE_ETH_RX_OFFLOAD_BIT2STR(_name) \ + { RTE_ETH_RX_OFFLOAD_##_name, #_name } + static const struct { uint64_t offload; const char *name; @@ -127,9 +130,11 @@ static const struct { RTE_RX_OFFLOAD_BIT2STR(SCTP_CKSUM), RTE_RX_OFFLOAD_BIT2STR(OUTER_UDP_CKSUM), RTE_RX_OFFLOAD_BIT2STR(RSS_HASH), + RTE_ETH_RX_OFFLOAD_BIT2STR(BUFFER_SPLIT), }; #undef RTE_RX_OFFLOAD_BIT2STR +#undef RTE_ETH_RX_OFFLOAD_BIT2STR #define RTE_TX_OFFLOAD_BIT2STR(_name) \ { DEV_TX_OFFLOAD_##_name, #_name } @@ -1814,6 +1819,77 @@ rte_eth_dev_is_removed(uint16_t port_id) return ret; } +static int +rte_eth_rx_queue_check_split(const struct rte_eth_rxseg_split *rx_seg, + uint16_t n_seg, uint32_t *mbp_buf_size, + const struct rte_eth_dev_info *dev_info) +{ + const struct rte_eth_rxseg_capa *seg_capa = &dev_info->rx_seg_capa; + struct rte_mempool *mp_first; + uint32_t offset_mask; + uint16_t seg_idx; + + if (n_seg > seg_capa->max_nseg) { + RTE_ETHDEV_LOG(ERR, + "Requested Rx segments %u exceed supported %u\n", + n_seg, seg_capa->max_nseg); + return -EINVAL; + } + /* + * Check the sizes and offsets against buffer sizes + * for each segment specified in extended configuration. + */ + mp_first = rx_seg[0].mp; + offset_mask = (1u << seg_capa->offset_align_log2) - 1; + for (seg_idx = 0; seg_idx < n_seg; seg_idx++) { + struct rte_mempool *mpl = rx_seg[seg_idx].mp; + uint32_t length = rx_seg[seg_idx].length; + uint32_t offset = rx_seg[seg_idx].offset; + + if (mpl == NULL) { + RTE_ETHDEV_LOG(ERR, "null mempool pointer\n"); + return -EINVAL; + } + if (seg_idx != 0 && mp_first != mpl && + seg_capa->multi_pools == 0) { + RTE_ETHDEV_LOG(ERR, "Receiving to multiple pools is not supported\n"); + return -ENOTSUP; + } + if (offset != 0) { + if (seg_capa->offset_allowed == 0) { + RTE_ETHDEV_LOG(ERR, "Rx segmentation with offset is not supported\n"); + return -ENOTSUP; + } + if (offset & offset_mask) { + RTE_ETHDEV_LOG(ERR, "Rx segmentation invalid offset alignment %u, %u\n", + offset, + seg_capa->offset_align_log2); + return -EINVAL; + } + } + if (mpl->private_data_size < + sizeof(struct rte_pktmbuf_pool_private)) { + RTE_ETHDEV_LOG(ERR, + "%s private_data_size %u < %u\n", + mpl->name, mpl->private_data_size, + (unsigned int)sizeof + (struct rte_pktmbuf_pool_private)); + return -ENOSPC; + } + offset += seg_idx != 0 ? 0 : RTE_PKTMBUF_HEADROOM; + *mbp_buf_size = rte_pktmbuf_data_room_size(mpl); + length = length != 0 ? length : *mbp_buf_size; + if (*mbp_buf_size < length + offset) { + RTE_ETHDEV_LOG(ERR, + "%s mbuf_data_room_size %u < %u (segment length=%u + segment offset=%u)\n", + mpl->name, *mbp_buf_size, + length + offset, length, offset); + return -EINVAL; + } + } + return 0; +} + int rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id, uint16_t nb_rx_desc, unsigned int socket_id, @@ -1835,38 +1911,65 @@ rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id, return -EINVAL; } - if (mp == NULL) { - RTE_ETHDEV_LOG(ERR, "Invalid null mempool pointer\n"); - return -EINVAL; - } - RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_setup, -ENOTSUP); - /* - * Check the size of the mbuf data buffer. - * This value must be provided in the private data of the memory pool. - * First check that the memory pool has a valid private data. - */ ret = rte_eth_dev_info_get(port_id, &dev_info); if (ret != 0) return ret; - if (mp->private_data_size < sizeof(struct rte_pktmbuf_pool_private)) { - RTE_ETHDEV_LOG(ERR, "%s private_data_size %d < %d\n", - mp->name, (int)mp->private_data_size, - (int)sizeof(struct rte_pktmbuf_pool_private)); - return -ENOSPC; - } - mbp_buf_size = rte_pktmbuf_data_room_size(mp); + if (mp != NULL) { + /* Single pool configuration check. */ + if (rx_conf != NULL && rx_conf->rx_nseg != 0) { + RTE_ETHDEV_LOG(ERR, + "Ambiguous segment configuration\n"); + return -EINVAL; + } + /* + * Check the size of the mbuf data buffer, this value + * must be provided in the private data of the memory pool. + * First check that the memory pool(s) has a valid private data. + */ + if (mp->private_data_size < + sizeof(struct rte_pktmbuf_pool_private)) { + RTE_ETHDEV_LOG(ERR, "%s private_data_size %u < %u\n", + mp->name, mp->private_data_size, + (unsigned int) + sizeof(struct rte_pktmbuf_pool_private)); + return -ENOSPC; + } + mbp_buf_size = rte_pktmbuf_data_room_size(mp); + if (mbp_buf_size < dev_info.min_rx_bufsize + + RTE_PKTMBUF_HEADROOM) { + RTE_ETHDEV_LOG(ERR, + "%s mbuf_data_room_size %u < %u (RTE_PKTMBUF_HEADROOM=%u + min_rx_bufsize(dev)=%u)\n", + mp->name, mbp_buf_size, + RTE_PKTMBUF_HEADROOM + + dev_info.min_rx_bufsize, + RTE_PKTMBUF_HEADROOM, + dev_info.min_rx_bufsize); + return -EINVAL; + } + } else { + const struct rte_eth_rxseg_split *rx_seg = + (const struct rte_eth_rxseg_split *)rx_conf->rx_seg; + uint16_t n_seg = rx_conf->rx_nseg; - if (mbp_buf_size < dev_info.min_rx_bufsize + RTE_PKTMBUF_HEADROOM) { - RTE_ETHDEV_LOG(ERR, - "%s mbuf_data_room_size %d < %d (RTE_PKTMBUF_HEADROOM=%d + min_rx_bufsize(dev)=%d)\n", - mp->name, (int)mbp_buf_size, - (int)(RTE_PKTMBUF_HEADROOM + dev_info.min_rx_bufsize), - (int)RTE_PKTMBUF_HEADROOM, - (int)dev_info.min_rx_bufsize); - return -EINVAL; + /* Extended multi-segment configuration check. */ + if (rx_conf == NULL || rx_conf->rx_seg == NULL || rx_conf->rx_nseg == 0) { + RTE_ETHDEV_LOG(ERR, + "Memory pool is null and no extended configuration provided\n"); + return -EINVAL; + } + if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT) { + ret = rte_eth_rx_queue_check_split(rx_seg, n_seg, + &mbp_buf_size, + &dev_info); + if (ret != 0) + return ret; + } else { + RTE_ETHDEV_LOG(ERR, "No Rx segmentation offload configured\n"); + return -EINVAL; + } } /* Use default specified by driver, if nb_rx_desc is zero */ diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h index f56cfa3396..0a134b697f 100644 --- a/lib/librte_ethdev/rte_ethdev.h +++ b/lib/librte_ethdev/rte_ethdev.h @@ -969,6 +969,61 @@ struct rte_eth_txmode { void *reserved_ptrs[2]; /**< Reserved for future fields */ }; +/** + * @warning + * @b EXPERIMENTAL: this structure may change without prior notice. + * + * A structure used to configure an Rx packet segment to split. + * + * If RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT flag is set in offloads field, + * the PMD will split the received packets into multiple segments + * according to the specification in the description array: + * + * - The first network buffer will be allocated from the memory pool, + * specified in the first array element, the second buffer, from the + * pool in the second element, and so on. + * + * - The offsets from the segment description elements specify + * the data offset from the buffer beginning except the first mbuf. + * The first segment offset is added with RTE_PKTMBUF_HEADROOM. + * + * - The lengths in the elements define the maximal data amount + * being received to each segment. The receiving starts with filling + * up the first mbuf data buffer up to specified length. If the + * there are data remaining (packet is longer than buffer in the first + * mbuf) the following data will be pushed to the next segment + * up to its own length, and so on. + * + * - If the length in the segment description element is zero + * the actual buffer size will be deduced from the appropriate + * memory pool properties. + * + * - If there is not enough elements to describe the buffer for entire + * packet of maximal length the following parameters will be used + * for the all remaining segments: + * - pool from the last valid element + * - the buffer size from this pool + * - zero offset + */ +struct rte_eth_rxseg_split { + struct rte_mempool *mp; /**< Memory pool to allocate segment from. */ + uint16_t length; /**< Segment data length, configures split point. */ + uint16_t offset; /**< Data offset from beginning of mbuf data buffer. */ + uint32_t reserved; /**< Reserved field. */ +}; + +/** + * @warning + * @b EXPERIMENTAL: this structure may change without prior notice. + * + * A common structure used to describe Rx packet segment properties. + */ +union rte_eth_rxseg { + /* The settings for buffer split offload. */ + struct rte_eth_rxseg_split split; + /* The other features settings should be added here. */ +}; + /** * A structure used to configure an RX ring of an Ethernet port. */ @@ -977,12 +1032,21 @@ struct rte_eth_rxconf { uint16_t rx_free_thresh; /**< Drives the freeing of RX descriptors. */ uint8_t rx_drop_en; /**< Drop packets if no descriptors are available. */ uint8_t rx_deferred_start; /**< Do not start queue with rte_eth_dev_start(). */ + uint16_t rx_nseg; /**< Number of descriptions in rx_seg array. */ /** * Per-queue Rx offloads to be set using DEV_RX_OFFLOAD_* flags. * Only offloads set on rx_queue_offload_capa or rx_offload_capa * fields on rte_eth_dev_info structure are allowed to be set. */ uint64_t offloads; + /** + * Points to the array of segment descriptions for an entire packet. + * Array elements are properties for consecutive Rx segments. + * + * The supported capabilities of receiving segmentation is reported + * in rte_eth_dev_info.rx_seg_capa field. + */ + union rte_eth_rxseg *rx_seg; uint64_t reserved_64s[2]; /**< Reserved for future fields */ void *reserved_ptrs[2]; /**< Reserved for future fields */ @@ -1285,6 +1349,7 @@ struct rte_eth_conf { #define DEV_RX_OFFLOAD_SCTP_CKSUM 0x00020000 #define DEV_RX_OFFLOAD_OUTER_UDP_CKSUM 0x00040000 #define DEV_RX_OFFLOAD_RSS_HASH 0x00080000 +#define RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT 0x00100000 #define DEV_RX_OFFLOAD_CHECKSUM (DEV_RX_OFFLOAD_IPV4_CKSUM | \ DEV_RX_OFFLOAD_UDP_CKSUM | \ @@ -1400,6 +1465,21 @@ struct rte_eth_switch_info { */ }; +/** + * @warning + * @b EXPERIMENTAL: this structure may change without prior notice. + * + * Ethernet device Rx buffer segmentation capabilities. + */ +struct rte_eth_rxseg_capa { + __extension__ + uint32_t multi_pools:1; /**< Supports receiving to multiple pools.*/ + uint32_t offset_allowed:1; /**< Supports buffer offsets. */ + uint32_t offset_align_log2:4; /**< Required offset alignment. */ + uint16_t max_nseg; /**< Maximum amount of segments to split. */ + uint16_t reserved; /**< Reserved field. */ +}; + /** * Ethernet device information */ @@ -1428,6 +1508,7 @@ struct rte_eth_dev_info { /** Maximum number of hash MAC addresses for MTA and UTA. */ uint16_t max_vfs; /**< Maximum number of VFs. */ uint16_t max_vmdq_pools; /**< Maximum number of VMDq pools. */ + struct rte_eth_rxseg_capa rx_seg_capa; /**< Segmentation capability.*/ uint64_t rx_offload_capa; /**< All RX offload capabilities including all per-queue ones */ uint64_t tx_offload_capa; @@ -2054,9 +2135,21 @@ rte_eth_dev_is_removed(uint16_t port_id); * No need to repeat any bit in rx_conf->offloads which has already been * enabled in rte_eth_dev_configure() at port level. An offloading enabled * at port level can't be disabled at queue level. + * The configuration structure also contains the pointer to the array + * of the receiving buffer segment descriptions, see rx_seg and rx_nseg + * fields, this extended configuration might be used by split offloads like + * RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT. If mp_pool is not NULL, + * the extended configuration fields must be set to NULL and zero. * @param mb_pool * The pointer to the memory pool from which to allocate *rte_mbuf* network - * memory buffers to populate each descriptor of the receive ring. + * memory buffers to populate each descriptor of the receive ring. There are + * two options to provide Rx buffer configuration: + * - single pool: + * mb_pool is not NULL, rx_conf.rx_nseg is 0. + * - multiple segments description: + * mb_pool is NULL, rx_conf.rx_seg is not NULL, rx_conf.rx_nseg is not 0. + * Taken only if flag RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT is set in offloads. + * * @return * - 0: Success, receive queue correctly set up. * - -EIO: if device is removed.