From c119edbc2d46c28eea28d2a691c78275e1e6acb6 Mon Sep 17 00:00:00 2001 From: Marvin Liu Date: Fri, 25 Oct 2019 00:08:28 +0800 Subject: [PATCH] vhost: update packed ring dequeue Buffer used ring updates as many as possible in vhost dequeue function for coordinating with virtio driver. For supporting buffer, shadow used ring element should contain descriptor's flags. First shadowed ring index was recorded for calculating buffered number. Signed-off-by: Marvin Liu Reviewed-by: Maxime Coquelin --- lib/librte_vhost/vhost.h | 5 ++ lib/librte_vhost/virtio_net.c | 112 ++++++++++++++++++++++++++++++++++ 2 files changed, 117 insertions(+) diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index f8dbe841c2..9f11b28a31 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -42,6 +42,8 @@ #define PACKED_DESC_ENQUEUE_USED_FLAG(w) \ ((w) ? (VRING_DESC_F_AVAIL | VRING_DESC_F_USED | VRING_DESC_F_WRITE) : \ VRING_DESC_F_WRITE) +#define PACKED_DESC_DEQUEUE_USED_FLAG(w) \ + ((w) ? (VRING_DESC_F_AVAIL | VRING_DESC_F_USED) : 0x0) #define PACKED_DESC_SINGLE_DEQUEUE_FLAG (VRING_DESC_F_NEXT | \ VRING_DESC_F_INDIRECT) @@ -114,6 +116,7 @@ struct log_cache_entry { struct vring_used_elem_packed { uint16_t id; + uint16_t flags; uint32_t len; uint32_t count; }; @@ -179,6 +182,8 @@ struct vhost_virtqueue { uint16_t shadow_used_idx; /* Record packed ring enqueue latest desc cache aligned index */ uint16_t shadow_aligned_idx; + /* Record packed ring first dequeue desc index */ + uint16_t shadow_last_used_idx; struct vhost_vring_addr ring_addrs; struct batch_copy_elem *batch_copy_elems; diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index 51ce320649..b09e03fbcc 100644 --- a/lib/librte_vhost/virtio_net.c +++ b/lib/librte_vhost/virtio_net.c @@ -154,6 +154,23 @@ vhost_flush_enqueue_shadow_packed(struct virtio_net *dev, vhost_log_cache_sync(dev, vq); } +static __rte_always_inline void +vhost_flush_dequeue_shadow_packed(struct virtio_net *dev, + struct vhost_virtqueue *vq) +{ + struct vring_used_elem_packed *used_elem = &vq->shadow_used_packed[0]; + + vq->desc_packed[vq->shadow_last_used_idx].id = used_elem->id; + rte_smp_wmb(); + vq->desc_packed[vq->shadow_last_used_idx].flags = used_elem->flags; + + vhost_log_cache_used_vring(dev, vq, vq->shadow_last_used_idx * + sizeof(struct vring_packed_desc), + sizeof(struct vring_packed_desc)); + vq->shadow_used_idx = 0; + vhost_log_cache_sync(dev, vq); +} + static __rte_always_inline void vhost_flush_enqueue_batch_packed(struct virtio_net *dev, struct vhost_virtqueue *vq, @@ -246,6 +263,78 @@ flush_shadow_used_ring_packed(struct virtio_net *dev, vhost_log_cache_sync(dev, vq); } +static __rte_always_inline void +vhost_shadow_dequeue_batch_packed(struct virtio_net *dev, + struct vhost_virtqueue *vq, + uint16_t *ids) +{ + uint16_t flags; + uint16_t i; + uint16_t begin; + + flags = PACKED_DESC_DEQUEUE_USED_FLAG(vq->used_wrap_counter); + + if (!vq->shadow_used_idx) { + vq->shadow_last_used_idx = vq->last_used_idx; + vq->shadow_used_packed[0].id = ids[0]; + vq->shadow_used_packed[0].len = 0; + vq->shadow_used_packed[0].count = 1; + vq->shadow_used_packed[0].flags = flags; + vq->shadow_used_idx++; + begin = 1; + } else + begin = 0; + + vhost_for_each_try_unroll(i, begin, PACKED_BATCH_SIZE) { + vq->desc_packed[vq->last_used_idx + i].id = ids[i]; + vq->desc_packed[vq->last_used_idx + i].len = 0; + } + + rte_smp_wmb(); + vhost_for_each_try_unroll(i, begin, PACKED_BATCH_SIZE) + vq->desc_packed[vq->last_used_idx + i].flags = flags; + + vhost_log_cache_used_vring(dev, vq, vq->last_used_idx * + sizeof(struct vring_packed_desc), + sizeof(struct vring_packed_desc) * + PACKED_BATCH_SIZE); + vhost_log_cache_sync(dev, vq); + + vq_inc_last_used_packed(vq, PACKED_BATCH_SIZE); +} + +static __rte_always_inline void +vhost_shadow_dequeue_single_packed(struct vhost_virtqueue *vq, + uint16_t buf_id, + uint16_t count) +{ + uint16_t flags; + + flags = vq->desc_packed[vq->last_used_idx].flags; + if (vq->used_wrap_counter) { + flags |= VRING_DESC_F_USED; + flags |= VRING_DESC_F_AVAIL; + } else { + flags &= ~VRING_DESC_F_USED; + flags &= ~VRING_DESC_F_AVAIL; + } + + if (!vq->shadow_used_idx) { + vq->shadow_last_used_idx = vq->last_used_idx; + + vq->shadow_used_packed[0].id = buf_id; + vq->shadow_used_packed[0].len = 0; + vq->shadow_used_packed[0].flags = flags; + vq->shadow_used_idx++; + } else { + vq->desc_packed[vq->last_used_idx].id = buf_id; + vq->desc_packed[vq->last_used_idx].len = 0; + vq->desc_packed[vq->last_used_idx].flags = flags; + } + + vq_inc_last_used_packed(vq, count); +} + static __rte_always_inline void update_shadow_used_ring_packed(struct vhost_virtqueue *vq, uint16_t desc_idx, uint32_t len, uint16_t count) @@ -314,6 +403,25 @@ vhost_shadow_enqueue_single_packed(struct virtio_net *dev, } } +static __rte_unused void +vhost_flush_dequeue_packed(struct virtio_net *dev, + struct vhost_virtqueue *vq) +{ + int shadow_count; + if (!vq->shadow_used_idx) + return; + + shadow_count = vq->last_used_idx - vq->shadow_last_used_idx; + if (shadow_count <= 0) + shadow_count += vq->size; + + if ((uint32_t)shadow_count >= (vq->size - MAX_PKT_BURST)) { + do_data_copy_dequeue(vq); + vhost_flush_dequeue_shadow_packed(dev, vq); + vhost_vring_call_packed(dev, vq); + } +} + /* avoid write operation when necessary, to lessen cache issues */ #define ASSIGN_UNLESS_EQUAL(var, val) do { \ if ((var) != (val)) \ @@ -1876,6 +1984,8 @@ virtio_dev_tx_batch_packed(struct virtio_net *dev, (void *)(uintptr_t)(desc_addrs[i] + buf_offset), pkts[i]->pkt_len); + vhost_shadow_dequeue_batch_packed(dev, vq, ids); + vq_inc_last_avail_packed(vq, PACKED_BATCH_SIZE); return 0; @@ -1931,6 +2041,8 @@ virtio_dev_tx_single_packed(struct virtio_net *dev, &desc_count)) return -1; + vhost_shadow_dequeue_single_packed(vq, buf_id, desc_count); + vq_inc_last_avail_packed(vq, desc_count); return 0; -- 2.20.1