+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;
+}
+