Re: [dpdk-dev] [PATCH v21 4/7] dmadev: introduce DMA device library implementation

["Walsh, Conor" <conor.walsh@intel.com>]

<snip>

Hi Chengwen,

While testing the IOAT driver I realised that we hadn't implemented the new RTE_DMADEV_ALL_VCHAN
flag for stats. Rather than every driver that only supports 1 vchan enabling support for this flag it would
probably be better to catch it in the library as shown below.

Thanks,
Conor.

> +int
> +rte_dmadev_stats_get(uint16_t dev_id, uint16_t vchan,
> +		     struct rte_dmadev_stats *stats)
> +{
> +	const struct rte_dmadev *dev = &rte_dmadevices[dev_id];
> +
> +	RTE_DMADEV_VALID_DEV_ID_OR_ERR_RET(dev_id, -EINVAL);
> +	if (stats == NULL)
> +		return -EINVAL;
> +	if (vchan >= dev->data->dev_conf.nb_vchans &&
> +	    vchan != RTE_DMADEV_ALL_VCHAN) {
> +		RTE_DMADEV_LOG(ERR,
> +			"Device %u vchan %u out of range", dev_id, vchan);
> +		return -EINVAL;
> +	}
	if (vchan == RTE_DMADEV_ALL_VCHAN && dev->data->dev_conf.nb_vchans == 1)
		vchan = 0;
> +
> +	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->stats_get, -
> ENOTSUP);
> +	memset(stats, 0, sizeof(struct rte_dmadev_stats));
> +	return (*dev->dev_ops->stats_get)(dev, vchan, stats,
> +					  sizeof(struct rte_dmadev_stats));
> +}
> +
> +int
> +rte_dmadev_stats_reset(uint16_t dev_id, uint16_t vchan)
> +{
> +	struct rte_dmadev *dev = &rte_dmadevices[dev_id];
> +
> +	RTE_DMADEV_VALID_DEV_ID_OR_ERR_RET(dev_id, -EINVAL);
> +	if (vchan >= dev->data->dev_conf.nb_vchans &&
> +	    vchan != RTE_DMADEV_ALL_VCHAN) {
> +		RTE_DMADEV_LOG(ERR,
> +			"Device %u vchan %u out of range", dev_id, vchan);
> +		return -EINVAL;
> +	}
	if (vchan == RTE_DMADEV_ALL_VCHAN && dev->data->dev_conf.nb_vchans == 1)
		vchan = 0;
> +
> +	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->stats_reset, -
> ENOTSUP);
> +	return (*dev->dev_ops->stats_reset)(dev, vchan);
> +}

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