From: Leyi Rong Date: Thu, 14 Jan 2021 06:39:51 +0000 (+0800) Subject: net/i40e: optimize Tx by using AVX512 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=5171b4ee6b6b19074194045f28639cb8c7874d04;p=dpdk.git net/i40e: optimize Tx by using AVX512 Optimize Tx path by using AVX512 instructions and vectorize the tx free bufs process. Signed-off-by: Leyi Rong Signed-off-by: Bruce Richardson Acked-by: Wenzhuo Lu --- diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c index 25963b382c..3574867685 100644 --- a/drivers/net/i40e/i40e_rxtx.c +++ b/drivers/net/i40e/i40e_rxtx.c @@ -2533,6 +2533,25 @@ i40e_tx_queue_release_mbufs(struct i40e_tx_queue *txq) * vPMD tx will not set sw_ring's mbuf to NULL after free, * so need to free remains more carefully. */ +#ifdef CC_AVX512_SUPPORT + if (dev->tx_pkt_burst == i40e_xmit_pkts_vec_avx512) { + struct i40e_vec_tx_entry *swr = (void *)txq->sw_ring; + + i = txq->tx_next_dd - txq->tx_rs_thresh + 1; + if (txq->tx_tail < i) { + for (; i < txq->nb_tx_desc; i++) { + rte_pktmbuf_free_seg(swr[i].mbuf); + swr[i].mbuf = NULL; + } + i = 0; + } + for (; i < txq->tx_tail; i++) { + rte_pktmbuf_free_seg(swr[i].mbuf); + swr[i].mbuf = NULL; + } + return; + } +#endif if (dev->tx_pkt_burst == i40e_xmit_pkts_vec_avx2 || dev->tx_pkt_burst == i40e_xmit_pkts_vec) { i = txq->tx_next_dd - txq->tx_rs_thresh + 1; diff --git a/drivers/net/i40e/i40e_rxtx.h b/drivers/net/i40e/i40e_rxtx.h index f4ad6b6b3b..3447a58c82 100644 --- a/drivers/net/i40e/i40e_rxtx.h +++ b/drivers/net/i40e/i40e_rxtx.h @@ -129,6 +129,10 @@ struct i40e_tx_entry { uint16_t last_id; }; +struct i40e_vec_tx_entry { + struct rte_mbuf *mbuf; +}; + /* * Structure associated with each TX queue. */ diff --git a/drivers/net/i40e/i40e_rxtx_vec_avx512.c b/drivers/net/i40e/i40e_rxtx_vec_avx512.c index 94075aa0fb..e92f97b7ed 100644 --- a/drivers/net/i40e/i40e_rxtx_vec_avx512.c +++ b/drivers/net/i40e/i40e_rxtx_vec_avx512.c @@ -873,6 +873,115 @@ i40e_recv_scattered_pkts_vec_avx512(void *rx_queue, rx_pkts + retval, nb_pkts); } +static __rte_always_inline int +i40e_tx_free_bufs_avx512(struct i40e_tx_queue *txq) +{ + struct i40e_vec_tx_entry *txep; + uint32_t n; + uint32_t i; + int nb_free = 0; + struct rte_mbuf *m, *free[RTE_I40E_TX_MAX_FREE_BUF_SZ]; + + /* check DD bits on threshold descriptor */ + if ((txq->tx_ring[txq->tx_next_dd].cmd_type_offset_bsz & + rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) != + rte_cpu_to_le_64(I40E_TX_DESC_DTYPE_DESC_DONE)) + return 0; + + n = txq->tx_rs_thresh; + + /* first buffer to free from S/W ring is at index + * tx_next_dd - (tx_rs_thresh-1) + */ + txep = (void *)txq->sw_ring; + txep += txq->tx_next_dd - (n - 1); + + if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE && (n & 31) == 0) { + struct rte_mempool *mp = txep[0].mbuf->pool; + void **cache_objs; + struct rte_mempool_cache *cache = rte_mempool_default_cache(mp, + rte_lcore_id()); + + if (!cache || cache->len == 0) + goto normal; + + cache_objs = &cache->objs[cache->len]; + + if (n > RTE_MEMPOOL_CACHE_MAX_SIZE) { + rte_mempool_ops_enqueue_bulk(mp, (void *)txep, n); + goto done; + } + + /* The cache follows the following algorithm + * 1. Add the objects to the cache + * 2. Anything greater than the cache min value (if it + * crosses the cache flush threshold) is flushed to the ring. + */ + /* Add elements back into the cache */ + uint32_t copied = 0; + /* n is multiple of 32 */ + while (copied < n) { + const __m512i a = _mm512_load_si512(&txep[copied]); + const __m512i b = _mm512_load_si512(&txep[copied + 8]); + const __m512i c = _mm512_load_si512(&txep[copied + 16]); + const __m512i d = _mm512_load_si512(&txep[copied + 24]); + + _mm512_storeu_si512(&cache_objs[copied], a); + _mm512_storeu_si512(&cache_objs[copied + 8], b); + _mm512_storeu_si512(&cache_objs[copied + 16], c); + _mm512_storeu_si512(&cache_objs[copied + 24], d); + copied += 32; + } + cache->len += n; + + if (cache->len >= cache->flushthresh) { + rte_mempool_ops_enqueue_bulk + (mp, &cache->objs[cache->size], + cache->len - cache->size); + cache->len = cache->size; + } + goto done; + } + +normal: + m = rte_pktmbuf_prefree_seg(txep[0].mbuf); + if (likely(m)) { + free[0] = m; + nb_free = 1; + for (i = 1; i < n; i++) { + rte_prefetch0(&txep[i + 3].mbuf->cacheline1); + m = rte_pktmbuf_prefree_seg(txep[i].mbuf); + if (likely(m)) { + if (likely(m->pool == free[0]->pool)) { + free[nb_free++] = m; + } else { + rte_mempool_put_bulk(free[0]->pool, + (void *)free, + nb_free); + free[0] = m; + nb_free = 1; + } + } + } + rte_mempool_put_bulk(free[0]->pool, (void **)free, nb_free); + } else { + for (i = 1; i < n; i++) { + m = rte_pktmbuf_prefree_seg(txep[i].mbuf); + if (m) + rte_mempool_put(m->pool, m); + } + } + +done: + /* buffers were freed, update counters */ + txq->nb_tx_free = (uint16_t)(txq->nb_tx_free + txq->tx_rs_thresh); + txq->tx_next_dd = (uint16_t)(txq->tx_next_dd + txq->tx_rs_thresh); + if (txq->tx_next_dd >= txq->nb_tx_desc) + txq->tx_next_dd = (uint16_t)(txq->tx_rs_thresh - 1); + + return txq->tx_rs_thresh; +} + static inline void vtx1(volatile struct i40e_tx_desc *txdp, struct rte_mbuf *pkt, uint64_t flags) { @@ -892,13 +1001,6 @@ vtx(volatile struct i40e_tx_desc *txdp, const uint64_t hi_qw_tmpl = (I40E_TX_DESC_DTYPE_DATA | ((uint64_t)flags << I40E_TXD_QW1_CMD_SHIFT)); - /* if unaligned on 32-bit boundary, do one to align */ - if (((uintptr_t)txdp & 0x1F) != 0 && nb_pkts != 0) { - vtx1(txdp, *pkt, flags); - nb_pkts--, txdp++, pkt++; - } - - /* do two at a time while possible, in bursts */ for (; nb_pkts > 3; txdp += 4, pkt += 4, nb_pkts -= 4) { uint64_t hi_qw3 = hi_qw_tmpl | @@ -917,14 +1019,13 @@ vtx(volatile struct i40e_tx_desc *txdp, ((uint64_t)pkt[0]->data_len << I40E_TXD_QW1_TX_BUF_SZ_SHIFT); - __m256i desc2_3 = _mm256_set_epi64x + __m512i desc0_3 = + _mm512_set_epi64 (hi_qw3, pkt[3]->buf_iova + pkt[3]->data_off, - hi_qw2, pkt[2]->buf_iova + pkt[2]->data_off); - __m256i desc0_1 = _mm256_set_epi64x - (hi_qw1, pkt[1]->buf_iova + pkt[1]->data_off, + hi_qw2, pkt[2]->buf_iova + pkt[2]->data_off, + hi_qw1, pkt[1]->buf_iova + pkt[1]->data_off, hi_qw0, pkt[0]->buf_iova + pkt[0]->data_off); - _mm256_store_si256((void *)(txdp + 2), desc2_3); - _mm256_store_si256((void *)txdp, desc0_1); + _mm512_storeu_si512((void *)txdp, desc0_3); } /* do any last ones */ @@ -934,13 +1035,23 @@ vtx(volatile struct i40e_tx_desc *txdp, } } +static __rte_always_inline void +tx_backlog_entry_avx512(struct i40e_vec_tx_entry *txep, + struct rte_mbuf **tx_pkts, uint16_t nb_pkts) +{ + int i; + + for (i = 0; i < (int)nb_pkts; ++i) + txep[i].mbuf = tx_pkts[i]; +} + static inline uint16_t i40e_xmit_fixed_burst_vec_avx512(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts) { struct i40e_tx_queue *txq = (struct i40e_tx_queue *)tx_queue; volatile struct i40e_tx_desc *txdp; - struct i40e_tx_entry *txep; + struct i40e_vec_tx_entry *txep; uint16_t n, nb_commit, tx_id; uint64_t flags = I40E_TD_CMD; uint64_t rs = I40E_TX_DESC_CMD_RS | I40E_TD_CMD; @@ -949,7 +1060,7 @@ i40e_xmit_fixed_burst_vec_avx512(void *tx_queue, struct rte_mbuf **tx_pkts, nb_pkts = RTE_MIN(nb_pkts, txq->tx_rs_thresh); if (txq->nb_tx_free < txq->tx_free_thresh) - i40e_tx_free_bufs(txq); + i40e_tx_free_bufs_avx512(txq); nb_commit = nb_pkts = (uint16_t)RTE_MIN(txq->nb_tx_free, nb_pkts); if (unlikely(nb_pkts == 0)) @@ -957,13 +1068,14 @@ i40e_xmit_fixed_burst_vec_avx512(void *tx_queue, struct rte_mbuf **tx_pkts, tx_id = txq->tx_tail; txdp = &txq->tx_ring[tx_id]; - txep = &txq->sw_ring[tx_id]; + txep = (void *)txq->sw_ring; + txep += tx_id; txq->nb_tx_free = (uint16_t)(txq->nb_tx_free - nb_pkts); n = (uint16_t)(txq->nb_tx_desc - tx_id); if (nb_commit >= n) { - tx_backlog_entry(txep, tx_pkts, n); + tx_backlog_entry_avx512(txep, tx_pkts, n); vtx(txdp, tx_pkts, n - 1, flags); tx_pkts += (n - 1); @@ -977,11 +1089,11 @@ i40e_xmit_fixed_burst_vec_avx512(void *tx_queue, struct rte_mbuf **tx_pkts, txq->tx_next_rs = (uint16_t)(txq->tx_rs_thresh - 1); /* avoid reach the end of ring */ - txdp = &txq->tx_ring[tx_id]; - txep = &txq->sw_ring[tx_id]; + txdp = txq->tx_ring; + txep = (void *)txq->sw_ring; } - tx_backlog_entry(txep, tx_pkts, nb_commit); + tx_backlog_entry_avx512(txep, tx_pkts, nb_commit); vtx(txdp, tx_pkts, nb_commit, flags);