Optimize vhost packed ring enqueue path with SIMD instructions. Four
descriptors status and length are batched handled with AVX512
instructions. Address translation operations are also accelerated
by AVX512 instructions.
Signed-off-by: Marvin Liu <yong....@intel.com>
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index fc7daf2145..b78b2c5c1b 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -1132,4 +1132,10 @@ vhost_reserve_avail_batch_packed_avx(struct virtio_net
*dev,
uint16_t avail_idx,
uintptr_t *desc_addrs,
uint16_t *ids);
+
+int
+virtio_dev_rx_batch_packed_avx(struct virtio_net *dev,
+ struct vhost_virtqueue *vq,
+ struct rte_mbuf **pkts);
+
#endif /* _VHOST_NET_CDEV_H_ */
diff --git a/lib/librte_vhost/vhost_vec_avx.c b/lib/librte_vhost/vhost_vec_avx.c
index dc5322d002..7d2250ed86 100644
--- a/lib/librte_vhost/vhost_vec_avx.c
+++ b/lib/librte_vhost/vhost_vec_avx.c
@@ -35,9 +35,15 @@
#define PACKED_AVAIL_FLAG ((0ULL | VRING_DESC_F_AVAIL) << FLAGS_BITS_OFFSET)
#define PACKED_AVAIL_FLAG_WRAP ((0ULL | VRING_DESC_F_USED) << \
FLAGS_BITS_OFFSET)
+#define PACKED_WRITE_AVAIL_FLAG (PACKED_AVAIL_FLAG | \
+ ((0ULL | VRING_DESC_F_WRITE) << FLAGS_BITS_OFFSET))
+#define PACKED_WRITE_AVAIL_FLAG_WRAP (PACKED_AVAIL_FLAG_WRAP | \
+ ((0ULL | VRING_DESC_F_WRITE) << FLAGS_BITS_OFFSET))
#define DESC_FLAGS_POS 0xaa
#define MBUF_LENS_POS 0x6666
+#define DESC_LENS_POS 0x4444
+#define DESC_LENS_FLAGS_POS 0xB0B0B0B0
int
vhost_reserve_avail_batch_packed_avx(struct virtio_net *dev,
@@ -179,3 +185,154 @@ vhost_reserve_avail_batch_packed_avx(struct virtio_net
*dev,
return -1;
}
+
+int
+virtio_dev_rx_batch_packed_avx(struct virtio_net *dev,
+ struct vhost_virtqueue *vq,
+ struct rte_mbuf **pkts)
+{
+ struct vring_packed_desc *descs = vq->desc_packed;
+ uint16_t avail_idx = vq->last_avail_idx;
+ uint64_t desc_addrs[PACKED_BATCH_SIZE];
+ uint32_t buf_offset = dev->vhost_hlen;
+ uint32_t desc_status;
+ uint64_t lens[PACKED_BATCH_SIZE];
+ uint16_t i;
+ void *desc_addr;
+ uint8_t cmp_low, cmp_high, cmp_result;
+
+ if (unlikely(avail_idx & PACKED_BATCH_MASK))
+ return -1;
+
+ /* check refcnt and nb_segs */
+ __m256i mbuf_ref = _mm256_set1_epi64x(DEFAULT_REARM_DATA);
+
+ /* load four mbufs rearm data */
+ __m256i mbufs = _mm256_set_epi64x(
+ *pkts[3]->rearm_data,
+ *pkts[2]->rearm_data,
+ *pkts[1]->rearm_data,
+ *pkts[0]->rearm_data);
+
+ uint16_t cmp = _mm256_cmpneq_epu16_mask(mbufs, mbuf_ref);
+ if (cmp & MBUF_LENS_POS)
+ return -1;
+
+ /* check desc status */
+ desc_addr = &vq->desc_packed[avail_idx];
+ __m512i desc_vec = _mm512_loadu_si512(desc_addr);
+
+ __m512i avail_flag_vec;
+ __m512i used_flag_vec;
+ if (vq->avail_wrap_counter) {
+#if defined(RTE_ARCH_I686)
+ avail_flag_vec = _mm512_set4_epi64(PACKED_WRITE_AVAIL_FLAG,
+ 0x0, PACKED_WRITE_AVAIL_FLAG, 0x0);
+ used_flag_vec = _mm512_set4_epi64(PACKED_FLAGS_MASK, 0x0,
+ PACKED_FLAGS_MASK, 0x0);
+#else
+ avail_flag_vec = _mm512_maskz_set1_epi64(DESC_FLAGS_POS,
+ PACKED_WRITE_AVAIL_FLAG);
+ used_flag_vec = _mm512_maskz_set1_epi64(DESC_FLAGS_POS,
+ PACKED_FLAGS_MASK);
+#endif
+ } else {
+#if defined(RTE_ARCH_I686)
+ avail_flag_vec = _mm512_set4_epi64(
+ PACKED_WRITE_AVAIL_FLAG_WRAP, 0x0,
+ PACKED_WRITE_AVAIL_FLAG, 0x0);
+ used_flag_vec = _mm512_set4_epi64(0x0, 0x0, 0x0, 0x0);
+#else
+ avail_flag_vec = _mm512_maskz_set1_epi64(DESC_FLAGS_POS,
+ PACKED_WRITE_AVAIL_FLAG_WRAP);
+ used_flag_vec = _mm512_setzero_epi32();
+#endif
+ }
+
+ desc_status = _mm512_mask_cmp_epu16_mask(BATCH_FLAGS_MASK, desc_vec,
+ avail_flag_vec, _MM_CMPINT_NE);
+ if (desc_status)
+ return -1;
+
+ if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)) {
+ vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+ uint64_t size = (uint64_t)descs[avail_idx + i].len;
+ desc_addrs[i] = __vhost_iova_to_vva(dev, vq,
+ descs[avail_idx + i].addr, &size,
+ VHOST_ACCESS_RW);
+
+ if (!desc_addrs[i])
+ return -1;
+
+ rte_prefetch0(rte_pktmbuf_mtod_offset(pkts[i], void *,
+ 0));
+ }
+ } else {
+ /* check buffer fit into one region & translate address */
+ __m512i regions_low_addrs =
+ _mm512_loadu_si512((void *)&dev->regions_low_addrs);
+ __m512i regions_high_addrs =
+ _mm512_loadu_si512((void *)&dev->regions_high_addrs);
+ vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+ uint64_t addr_low = descs[avail_idx + i].addr;
+ uint64_t addr_high = addr_low +
+ descs[avail_idx + i].len;
+ __m512i low_addr_vec = _mm512_set1_epi64(addr_low);
+ __m512i high_addr_vec = _mm512_set1_epi64(addr_high);
+
+ cmp_low = _mm512_cmp_epi64_mask(low_addr_vec,
+ regions_low_addrs, _MM_CMPINT_NLT);
+ cmp_high = _mm512_cmp_epi64_mask(high_addr_vec,
+ regions_high_addrs, _MM_CMPINT_LT);
+ cmp_result = cmp_low & cmp_high;
+ int index = __builtin_ctz(cmp_result);
+ if (unlikely((uint32_t)index >= dev->mem->nregions))
+ return -1;
+
+ desc_addrs[i] = addr_low +
+ dev->mem->regions[index].host_user_addr -
+ dev->mem->regions[index].guest_phys_addr;
+ rte_prefetch0(rte_pktmbuf_mtod_offset(pkts[i], void *,
+ 0));
+ }
+ }
+
+ /* check length is enough */
+ __m512i pkt_lens = _mm512_set_epi32(
+ 0, pkts[3]->pkt_len, 0, 0,
+ 0, pkts[2]->pkt_len, 0, 0,
+ 0, pkts[1]->pkt_len, 0, 0,
+ 0, pkts[0]->pkt_len, 0, 0);
+
+ __m512i mbuf_len_offset = _mm512_maskz_set1_epi32(DESC_LENS_POS,
+ dev->vhost_hlen);
+ __m512i buf_len_vec = _mm512_add_epi32(pkt_lens, mbuf_len_offset);
+ uint16_t lens_cmp = _mm512_mask_cmp_epu32_mask(DESC_LENS_POS,
+ desc_vec, buf_len_vec, _MM_CMPINT_LT);
+ if (lens_cmp)
+ return -1;
+
+ vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+ rte_memcpy((void *)(uintptr_t)(desc_addrs[i] + buf_offset),
+ rte_pktmbuf_mtod_offset(pkts[i], void *, 0),
+ pkts[i]->pkt_len);
+ }
+
+ if (unlikely((dev->features & (1ULL << VHOST_F_LOG_ALL)))) {
+ vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+ lens[i] = descs[avail_idx + i].len;
+ vhost_log_cache_write_iova(dev, vq,
+ descs[avail_idx + i].addr, lens[i]);
+ }
+ }
+
+ vq_inc_last_avail_packed(vq, PACKED_BATCH_SIZE);
+ vq_inc_last_used_packed(vq, PACKED_BATCH_SIZE);
+ /* save len and flags, skip addr and id */
+ __m512i desc_updated = _mm512_mask_add_epi16(desc_vec,
+ DESC_LENS_FLAGS_POS, buf_len_vec,
+ used_flag_vec);
+ _mm512_storeu_si512(desc_addr, desc_updated);
+
+ return 0;
+}
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index e4d2e2e7d6..5c56a8d6ff 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -1354,6 +1354,21 @@ virtio_dev_rx_single_packed(struct virtio_net *dev,
return 0;
}
+static __rte_always_inline int
+virtio_dev_rx_handle_batch_packed(struct virtio_net *dev,
+ struct vhost_virtqueue *vq,
+ struct rte_mbuf **pkts)
+
+{
+ if (unlikely(dev->vectorized))
+#ifdef CC_AVX512_SUPPORT
+ return virtio_dev_rx_batch_packed_avx(dev, vq, pkts);
+#else
+ return virtio_dev_rx_batch_packed(dev, vq, pkts);
+#endif
+ return virtio_dev_rx_batch_packed(dev, vq, pkts);
+}
+
static __rte_noinline uint32_t
virtio_dev_rx_packed(struct virtio_net *dev,
struct vhost_virtqueue *__rte_restrict vq,
@@ -1367,8 +1382,8 @@ virtio_dev_rx_packed(struct virtio_net *dev,
rte_prefetch0(&vq->desc_packed[vq->last_avail_idx]);
if (remained >= PACKED_BATCH_SIZE) {
- if (!virtio_dev_rx_batch_packed(dev, vq,
- &pkts[pkt_idx])) {
+ if (!virtio_dev_rx_handle_batch_packed(dev, vq,
+ &pkts[pkt_idx])) {
pkt_idx += PACKED_BATCH_SIZE;
remained -= PACKED_BATCH_SIZE;
continue;
--
2.17.1
