From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhihong Wang Subject: [PATCH v4 5/6] vhost: batch update used ring Date: Mon, 29 Aug 2016 23:36:03 -0400 Message-ID: <1472528164-54296-6-git-send-email-zhihong.wang@intel.com> References: <1471319402-112998-1-git-send-email-zhihong.wang@intel.com> <1472528164-54296-1-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 mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id CE9843990 for ; Tue, 30 Aug 2016 12:44:03 +0200 (CEST) In-Reply-To: <1472528164-54296-1-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. --- Changes in v4: 1. Free shadow used ring in the right place. 2. Add failure check for shadow used ring malloc. Signed-off-by: Zhihong Wang --- lib/librte_vhost/vhost-net.h | 4 +++ lib/librte_vhost/vhost_rxtx.c | 62 ++++++++++++++++++++++++++++++++++++------- lib/librte_vhost/virtio-net.c | 42 ++++++++++++++++++++++++++--- 3 files changed, 95 insertions(+), 13 deletions(-) diff --git a/lib/librte_vhost/vhost-net.h b/lib/librte_vhost/vhost-net.h index 51fdf3d..a15182c 100644 --- a/lib/librte_vhost/vhost-net.h +++ b/lib/librte_vhost/vhost-net.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_rxtx.c b/lib/librte_vhost/vhost_rxtx.c index 927896c..ddc7b21 100644 --- a/lib/librte_vhost/vhost_rxtx.c +++ b/lib/librte_vhost/vhost_rxtx.c @@ -134,16 +134,51 @@ 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_round = vq->last_used_idx & (vq->size - 1); + 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++; +} + +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; - vq->used->ring[used_idx_round].id = desc_chain_head; - vq->used->ring[used_idx_round].len = desc_chain_len; - vhost_log_used_vring(dev, vq, offsetof(struct vring_used, - ring[used_idx_round]), - sizeof(vq->used->ring[used_idx_round])); + 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 uint32_t __attribute__((always_inline)) @@ -208,7 +243,7 @@ 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); vq->last_used_idx++; extra_buffers++; @@ -245,7 +280,7 @@ enqueue_packet(struct virtio_net *dev, struct vhost_virtqueue *vq, desc_chain_len += copy_len; } - update_used_ring(dev, vq, desc_chain_head, desc_chain_len); + update_used_ring(vq, desc_chain_head, desc_chain_len); vq->last_used_idx++; return 0; @@ -276,6 +311,7 @@ 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 pkt_left = count; uint32_t pkt_idx = 0; uint32_t pkt_sent = 0; @@ -302,6 +338,8 @@ 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 */ @@ -319,6 +357,10 @@ 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_sent) notify_guest(dev, vq); diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c index 1785695..7416079 100644 --- a/lib/librte_vhost/virtio-net.c +++ b/lib/librte_vhost/virtio-net.c @@ -152,10 +152,26 @@ 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); } @@ -418,13 +434,26 @@ int vhost_set_vring_num(int vid, struct vhost_vring_state *state) { struct virtio_net *dev; + struct vhost_virtqueue *vq; dev = get_device(vid); if (dev == NULL) return -1; /* State->index refers to the queue index. The txq is 1, rxq is 0. */ - dev->virtqueue[state->index]->size = state->num; + 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; } @@ -610,6 +639,7 @@ int vhost_get_vring_base(int vid, uint32_t index, struct vhost_vring_state *state) { + struct vhost_virtqueue *vq; struct virtio_net *dev; dev = get_device(vid); @@ -617,6 +647,12 @@ vhost_get_vring_base(int vid, uint32_t index, return -1; state->index = index; + vq = dev->virtqueue[state->index]; + if (vq->shadow_used_ring) { + rte_free(vq->shadow_used_ring); + vq->shadow_used_ring = NULL; + } + /* State->index refers to the queue index. The txq is 1, rxq is 0. */ state->num = dev->virtqueue[state->index]->last_used_idx; -- 2.7.4