From patchwork Fri May 17 12:22:19 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxime Coquelin X-Patchwork-Id: 53522 Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 81F07D189; Fri, 17 May 2019 14:22:52 +0200 (CEST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id 3A286D17B for ; Fri, 17 May 2019 14:22:51 +0200 (CEST) Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 97E30B2DCD; Fri, 17 May 2019 12:22:50 +0000 (UTC) Received: from localhost.localdomain (ovpn-112-59.ams2.redhat.com [10.36.112.59]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9F06010027B9; Fri, 17 May 2019 12:22:43 +0000 (UTC) From: Maxime Coquelin To: dev@dpdk.org, tiwei.bie@intel.com, jfreimann@redhat.com, zhihong.wang@intel.com, bruce.richardson@intel.com, konstantin.ananyev@intel.com Cc: Maxime Coquelin Date: Fri, 17 May 2019 14:22:19 +0200 Message-Id: <20190517122220.31283-5-maxime.coquelin@redhat.com> In-Reply-To: <20190517122220.31283-1-maxime.coquelin@redhat.com> References: <20190517122220.31283-1-maxime.coquelin@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 17 May 2019 12:22:50 +0000 (UTC) Subject: [dpdk-dev] [PATCH 4/5] vhost: simplify descriptor's buffer prefetching X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Now that we have a single function to map the descriptors buffers, let's prefetch them there as it is the earliest place we can do it. Signed-off-by: Maxime Coquelin --- lib/librte_vhost/virtio_net.c | 32 ++------------------------------ 1 file changed, 2 insertions(+), 30 deletions(-) diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index 494dd9957e..d9031fe55c 100644 --- a/lib/librte_vhost/virtio_net.c +++ b/lib/librte_vhost/virtio_net.c @@ -286,6 +286,8 @@ map_one_desc(struct virtio_net *dev, struct vhost_virtqueue *vq, if (unlikely(!desc_addr)) return -1; + rte_prefetch0((void *)(uintptr_t)desc_addr); + buf_vec[vec_id].buf_iova = desc_iova; buf_vec[vec_id].buf_addr = desc_addr; buf_vec[vec_id].buf_len = desc_chunck_len; @@ -664,9 +666,6 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq, buf_iova = buf_vec[vec_idx].buf_iova; buf_len = buf_vec[vec_idx].buf_len; - if (nr_vec > 1) - rte_prefetch0((void *)(uintptr_t)buf_vec[1].buf_addr); - if (unlikely(buf_len < dev->vhost_hlen && nr_vec <= 1)) { error = -1; goto out; @@ -709,10 +708,6 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq, buf_iova = buf_vec[vec_idx].buf_iova; buf_len = buf_vec[vec_idx].buf_len; - /* Prefetch next buffer address. */ - if (vec_idx + 1 < nr_vec) - rte_prefetch0((void *)(uintptr_t) - buf_vec[vec_idx + 1].buf_addr); buf_offset = 0; buf_avail = buf_len; } @@ -810,8 +805,6 @@ virtio_dev_rx_split(struct virtio_net *dev, struct vhost_virtqueue *vq, break; } - rte_prefetch0((void *)(uintptr_t)buf_vec[0].buf_addr); - VHOST_LOG_DEBUG(VHOST_DATA, "(%d) current index %d | end index %d\n", dev->vid, vq->last_avail_idx, vq->last_avail_idx + num_buffers); @@ -859,8 +852,6 @@ virtio_dev_rx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq, break; } - rte_prefetch0((void *)(uintptr_t)buf_vec[0].buf_addr); - VHOST_LOG_DEBUG(VHOST_DATA, "(%d) current index %d | end index %d\n", dev->vid, vq->last_avail_idx, vq->last_avail_idx + num_buffers); @@ -1120,16 +1111,12 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq, goto out; } - if (likely(nr_vec > 1)) - rte_prefetch0((void *)(uintptr_t)buf_vec[1].buf_addr); - if (virtio_net_with_host_offload(dev)) { if (unlikely(buf_len < sizeof(struct virtio_net_hdr))) { copy_vnet_hdr_from_desc(&tmp_hdr, buf_vec); hdr = &tmp_hdr; } else { hdr = (struct virtio_net_hdr *)((uintptr_t)buf_addr); - rte_prefetch0(hdr); } } @@ -1159,9 +1146,6 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq, buf_avail = buf_vec[vec_idx].buf_len - dev->vhost_hlen; } - rte_prefetch0((void *)(uintptr_t) - (buf_addr + buf_offset)); - PRINT_PACKET(dev, (uintptr_t)(buf_addr + buf_offset), (uint32_t)buf_avail, 0); @@ -1227,14 +1211,6 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq, buf_iova = buf_vec[vec_idx].buf_iova; buf_len = buf_vec[vec_idx].buf_len; - /* - * Prefecth desc n + 1 buffer while - * desc n buffer is processed. - */ - if (vec_idx + 1 < nr_vec) - rte_prefetch0((void *)(uintptr_t) - buf_vec[vec_idx + 1].buf_addr); - buf_offset = 0; buf_avail = buf_len; @@ -1378,8 +1354,6 @@ virtio_dev_tx_split(struct virtio_net *dev, struct vhost_virtqueue *vq, if (likely(dev->dequeue_zero_copy == 0)) update_shadow_used_ring_split(vq, head_idx, 0); - rte_prefetch0((void *)(uintptr_t)buf_vec[0].buf_addr); - pkts[i] = rte_pktmbuf_alloc(mbuf_pool); if (unlikely(pkts[i] == NULL)) { RTE_LOG(ERR, VHOST_DATA, @@ -1489,8 +1463,6 @@ virtio_dev_tx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq, update_shadow_used_ring_packed(vq, buf_id, 0, desc_count); - rte_prefetch0((void *)(uintptr_t)buf_vec[0].buf_addr); - pkts[i] = rte_pktmbuf_alloc(mbuf_pool); if (unlikely(pkts[i] == NULL)) { RTE_LOG(ERR, VHOST_DATA,