[dpdk-dev] [PATCH] vhost: do deep copy while reallocate vq

[Yang, Zhiyong]

Hi Junjie,

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Junjie Chen
> Sent: Monday, January 15, 2018 7:32 PM
> To: yliu at fridaylinux.org; maxime.coquelin at redhat.com
> Cc: dev at dpdk.org; Chen, Junjie J <junjie.j.chen at intel.com>
> Subject: [dpdk-dev] [PATCH] vhost: do deep copy while reallocate vq
> 
> When vhost reallocate dev and vq for NUMA enabled case, it doesn't
> perform deep copy, which lead to 1) zmbuf list not valid 2) remote memory
> access.
> This patch is to re-initlize the zmbuf list and also do the deep copy.
> 
> Signed-off-by: Junjie Chen <junjie.j.chen at intel.com>
> ---
>  lib/librte_vhost/vhost_user.c | 31 +++++++++++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
> 
> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> index f4c7ce4..795462c 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -227,6 +227,7 @@ vhost_user_set_vring_num(struct virtio_net *dev,
>  				"zero copy is force disabled\n");
>  			dev->dequeue_zero_copy = 0;
>  		}
> +		TAILQ_INIT(&vq->zmbuf_list);
>  	}
> 
>  	vq->shadow_used_ring = rte_malloc(NULL, @@ -261,6 +262,9 @@
> numa_realloc(struct virtio_net *dev, int index)
>  	int oldnode, newnode;
>  	struct virtio_net *old_dev;
>  	struct vhost_virtqueue *old_vq, *vq;
> +	struct zcopy_mbuf *new_zmbuf;
> +	struct vring_used_elem *new_shadow_used_ring;
> +	struct batch_copy_elem *new_batch_copy_elems;
>  	int ret;
> 
>  	old_dev = dev;
> @@ -285,6 +289,33 @@ numa_realloc(struct virtio_net *dev, int index)
>  			return dev;
> 
>  		memcpy(vq, old_vq, sizeof(*vq));
> +		TAILQ_INIT(&vq->zmbuf_list);
> +
> +		new_zmbuf = rte_malloc_socket(NULL, vq->zmbuf_size *
> +			sizeof(struct zcopy_mbuf), 0, newnode);
> +		if (new_zmbuf) {
> +			rte_free(vq->zmbufs);
> +			vq->zmbufs = new_zmbuf;
> +		}

You need to consider how to handle the case  ( rte_malloc_socket return NULL).

> +		new_shadow_used_ring = rte_malloc_socket(NULL,
> +			vq->size * sizeof(struct vring_used_elem),
> +			RTE_CACHE_LINE_SIZE,
> +			newnode);
> +		if (new_shadow_used_ring) {
> +			rte_free(vq->shadow_used_ring);
> +			vq->shadow_used_ring = new_shadow_used_ring;
> +		}
> +

Ditto

> +		new_batch_copy_elems = rte_malloc_socket(NULL,
> +			vq->size * sizeof(struct batch_copy_elem),
> +			RTE_CACHE_LINE_SIZE,
> +			newnode);
> +		if (new_batch_copy_elems) {
> +			rte_free(vq->batch_copy_elems);
> +			vq->batch_copy_elems = new_batch_copy_elems;
> +		}

Ditto

> +
>  		rte_free(old_vq);
>  	}
> 
> --
> 2.0.1