From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhihong Wang Subject: [PATCH v5 5/6] vhost: batch update used ring Date: Thu, 8 Sep 2016 23:39:27 -0400 Message-ID: <1473392368-84903-6-git-send-email-zhihong.wang@intel.com> References: <1471319402-112998-1-git-send-email-zhihong.wang@intel.com> <1473392368-84903-1-git-send-email-zhihong.wang@intel.com> Cc: maxime.coquelin@redhat.com, yuanhan.liu@linux.intel.com, thomas.monjalon@6wind.com, Zhihong Wang To: dev@dpdk.org Return-path: Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by dpdk.org (Postfix) with ESMTP id 518147EF0 for ; Fri, 9 Sep 2016 12:47:27 +0200 (CEST) In-Reply-To: <1473392368-84903-1-git-send-email-zhihong.wang@intel.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" This patch enables batch update of the used ring for better efficiency. Signed-off-by: Zhihong Wang --- Changes in v4: 1. Free shadow used ring in the right place. 2. Add failure check for shadow used ring malloc. lib/librte_vhost/vhost.c | 20 ++++++++++++-- lib/librte_vhost/vhost.h | 4 +++ lib/librte_vhost/vhost_user.c | 31 +++++++++++++++++---- lib/librte_vhost/virtio_net.c | 64 +++++++++++++++++++++++++++++++++++-------- 4 files changed, 101 insertions(+), 18 deletions(-) diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c index 46095c3..cb31cdd 100644 --- a/lib/librte_vhost/vhost.c +++ b/lib/librte_vhost/vhost.c @@ -119,10 +119,26 @@ cleanup_device(struct virtio_net *dev, int destroy) static void free_device(struct virtio_net *dev) { + struct vhost_virtqueue *vq_0; + struct vhost_virtqueue *vq_1; uint32_t i; - for (i = 0; i < dev->virt_qp_nb; i++) - rte_free(dev->virtqueue[i * VIRTIO_QNUM]); + for (i = 0; i < dev->virt_qp_nb; i++) { + vq_0 = dev->virtqueue[i * VIRTIO_QNUM]; + if (vq_0->shadow_used_ring) { + rte_free(vq_0->shadow_used_ring); + vq_0->shadow_used_ring = NULL; + } + + vq_1 = dev->virtqueue[i * VIRTIO_QNUM + 1]; + if (vq_1->shadow_used_ring) { + rte_free(vq_1->shadow_used_ring); + vq_1->shadow_used_ring = NULL; + } + + /* malloc together, free together */ + rte_free(vq_0); + } rte_free(dev); } diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 9707dfc..381dc27 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -85,6 +85,10 @@ struct vhost_virtqueue { /* Physical address of used ring, for logging */ uint64_t log_guest_addr; + + /* Shadow used ring for performance */ + struct vring_used_elem *shadow_used_ring; + uint32_t shadow_used_idx; } __rte_cache_aligned; /* Old kernels have no such macro defined */ diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index eee99e9..d7cf1ed 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -193,7 +193,21 @@ static int vhost_user_set_vring_num(struct virtio_net *dev, struct vhost_vring_state *state) { - dev->virtqueue[state->index]->size = state->num; + struct vhost_virtqueue *vq; + + vq = dev->virtqueue[state->index]; + vq->size = state->num; + if (!vq->shadow_used_ring) { + vq->shadow_used_ring = rte_malloc(NULL, + vq->size * sizeof(struct vring_used_elem), + RTE_CACHE_LINE_SIZE); + if (!vq->shadow_used_ring) { + RTE_LOG(ERR, VHOST_CONFIG, + "Failed to allocate memory" + " for shadow used ring.\n"); + return -1; + } + } return 0; } @@ -611,14 +625,21 @@ static int vhost_user_get_vring_base(struct virtio_net *dev, struct vhost_vring_state *state) { + struct vhost_virtqueue *vq; + /* We have to stop the queue (virtio) if it is running. */ if (dev->flags & VIRTIO_DEV_RUNNING) { dev->flags &= ~VIRTIO_DEV_RUNNING; notify_ops->destroy_device(dev->vid); } + vq = dev->virtqueue[state->index]; /* Here we are safe to get the last used index */ - state->num = dev->virtqueue[state->index]->last_used_idx; + state->num = vq->last_used_idx; + if (vq->shadow_used_ring) { + rte_free(vq->shadow_used_ring); + vq->shadow_used_ring = NULL; + } RTE_LOG(INFO, VHOST_CONFIG, "vring base idx:%d file:%d\n", state->index, state->num); @@ -627,10 +648,10 @@ vhost_user_get_vring_base(struct virtio_net *dev, * sent and only sent in vhost_vring_stop. * TODO: cleanup the vring, it isn't usable since here. */ - if (dev->virtqueue[state->index]->kickfd >= 0) - close(dev->virtqueue[state->index]->kickfd); + if (vq->kickfd >= 0) + close(vq->kickfd); - dev->virtqueue[state->index]->kickfd = VIRTIO_UNINITIALIZED_EVENTFD; + vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD; return 0; } diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index b38f18f..e9f6353 100644 --- a/lib/librte_vhost/virtio_net.c +++ b/lib/librte_vhost/virtio_net.c @@ -134,17 +134,52 @@ virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr) } static inline void __attribute__((always_inline)) -update_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq, - uint32_t desc_chain_head, uint32_t desc_chain_len) +update_used_ring(struct vhost_virtqueue *vq, uint32_t desc_chain_head, + uint32_t desc_chain_len) { - uint32_t used_idx = vq->last_used_idx & (vq->size - 1); - - vq->used->ring[used_idx].id = desc_chain_head; - vq->used->ring[used_idx].len = desc_chain_len; + vq->shadow_used_ring[vq->shadow_used_idx].id = desc_chain_head; + vq->shadow_used_ring[vq->shadow_used_idx].len = desc_chain_len; + vq->shadow_used_idx++; vq->last_used_idx++; - vhost_log_used_vring(dev, vq, offsetof(struct vring_used, - ring[used_idx]), - sizeof(vq->used->ring[used_idx])); +} + +static inline void __attribute__((always_inline)) +flush_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint32_t used_idx_start) +{ + if (used_idx_start + vq->shadow_used_idx < vq->size) { + rte_memcpy(&vq->used->ring[used_idx_start], + &vq->shadow_used_ring[0], + vq->shadow_used_idx * + sizeof(struct vring_used_elem)); + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, + ring[used_idx_start]), + vq->shadow_used_idx * + sizeof(struct vring_used_elem)); + } else { + uint32_t part_1 = vq->size - used_idx_start; + uint32_t part_2 = vq->shadow_used_idx - part_1; + + rte_memcpy(&vq->used->ring[used_idx_start], + &vq->shadow_used_ring[0], + part_1 * + sizeof(struct vring_used_elem)); + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, + ring[used_idx_start]), + part_1 * + sizeof(struct vring_used_elem)); + rte_memcpy(&vq->used->ring[0], + &vq->shadow_used_ring[part_1], + part_2 * + sizeof(struct vring_used_elem)); + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, + ring[0]), + part_2 * + sizeof(struct vring_used_elem)); + } } static inline int __attribute__((always_inline)) @@ -209,7 +244,7 @@ enqueue_packet(struct virtio_net *dev, struct vhost_virtqueue *vq, goto error; } else if (is_mrg_rxbuf) { /* start with the next desc chain */ - update_used_ring(dev, vq, desc_chain_head, + update_used_ring(vq, desc_chain_head, desc_chain_len); num_buffers++; virtio_hdr->num_buffers++; @@ -245,7 +280,7 @@ enqueue_packet(struct virtio_net *dev, struct vhost_virtqueue *vq, desc_chain_len += cpy_len; } - update_used_ring(dev, vq, desc_chain_head, desc_chain_len); + update_used_ring(vq, desc_chain_head, desc_chain_len); return 0; @@ -275,6 +310,7 @@ rte_vhost_enqueue_burst(int vid, uint16_t queue_id, { struct vhost_virtqueue *vq; struct virtio_net *dev; + uint32_t used_idx_start; uint32_t is_mrg_rxbuf = 0; uint32_t pkt_idx = 0; uint32_t pkt_left = count; @@ -300,6 +336,8 @@ rte_vhost_enqueue_burst(int vid, uint16_t queue_id, is_mrg_rxbuf = 1; /* start enqueuing packets 1 by 1 */ + vq->shadow_used_idx = 0; + used_idx_start = vq->last_used_idx & (vq->size - 1); avail_idx = *((volatile uint16_t *)&vq->avail->idx); while (pkt_left && avail_idx != vq->last_used_idx) { /* prefetch the next desc */ @@ -316,6 +354,10 @@ rte_vhost_enqueue_burst(int vid, uint16_t queue_id, pkt_left--; } + /* batch update used ring for better performance */ + if (likely(vq->shadow_used_idx > 0)) + flush_used_ring(dev, vq, used_idx_start); + /* update used idx and kick the guest if necessary */ if (pkt_idx) notify_guest(dev, vq); -- 2.7.4