Re: [dpdk-dev] [PATCH] examples/vhost: add error propagation in ioat ops

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 1/31/21 1:36 PM, Cheng Jiang wrote:
> It makes more sense to add error propagation for rte_ioat_completed_ops.
> 
> Signed-off-by: Cheng Jiang <Cheng1.jiang@intel.com>
> ---
>  examples/vhost/ioat.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/examples/vhost/ioat.c b/examples/vhost/ioat.c
> index dbad28d43..60b73be93 100644
> --- a/examples/vhost/ioat.c
> +++ b/examples/vhost/ioat.c
> @@ -22,7 +22,6 @@ struct packet_tracker {
>  
>  struct packet_tracker cb_tracker[MAX_VHOST_DEVICE];
>  
> -
>  int
>  open_ioat(const char *value)
>  {
> @@ -129,7 +128,7 @@ ioat_transfer_data_cb(int vid, uint16_t queue_id,
>  		struct rte_vhost_async_status *opaque_data, uint16_t count)
>  {
>  	uint32_t i_desc;
> -	int dev_id = dma_bind[vid].dmas[queue_id * 2 + VIRTIO_RXQ].dev_id;
> +	uint16_t dev_id = dma_bind[vid].dmas[queue_id * 2 + VIRTIO_RXQ].dev_id;

This change from uint16_t to int does not seem related to the purpose of
this patch. Is it?

>  	struct rte_vhost_iov_iter *src = NULL;
>  	struct rte_vhost_iov_iter *dst = NULL;
>  	unsigned long i_seg;
> @@ -182,10 +181,17 @@ ioat_check_completed_copies_cb(int vid, uint16_t queue_id,
>  		unsigned short mask = MAX_ENQUEUED_SIZE - 1;
>  		unsigned short i;
>  
> -		int dev_id = dma_bind[vid].dmas[queue_id * 2
> +		uint16_t dev_id = dma_bind[vid].dmas[queue_id * 2
>  				+ VIRTIO_RXQ].dev_id;
>  		n_seg = rte_ioat_completed_ops(dev_id, 255, dump, dump);
> -		if (n_seg <= 0)
> +		if (n_seg < 0) {
> +			RTE_LOG(ERR,
> +				VHOST_DATA,
> +				"fail to poll completed buf on IOAT device %u",
> +				dev_id);
> +			return 0;
> +		}
> +		if (n_seg == 0)
>  			return 0;
>  
>  		cb_tracker[dev_id].ioat_space += n_seg;
>