Re: [dpdk-dev] [PATCH v2] ethdev: add sanity checks in control APIs

[Thomas Monjalon <thomas@monjalon.net>]

13/04/2021 10:44, Andrew Rybchenko:
> On 4/13/21 6:22 AM, Min Hu (Connor) wrote:
> > @@ -678,6 +684,9 @@ rte_eth_dev_owner_set(const uint16_t port_id,
> >  {
> >  	int ret;
> >  
> > +	if (owner == NULL)
> > +		return -EINVAL;
> > +
> 
> Here and in many-many cases below I think the order of checks
> is important in cases when different error codes are returned.
> When there is no any very good reasons why arguments should
> be checked in different order, arguments should be checked in
> order specified in function prototype. In this cases (and many
> cases below), port_id should be checked first.
> 
> In this particular case it means that the pointer check
> should be done in a static helper function.
> 
> One more point is error logging in the case of failure.
> Right now I'd use RTE_ETHDEV_LOG(ERR, ...). May be later we'll
> find out that some of messages should be made INFO or DEBUG.
> Something like:
>    RTE_ETHDEV_LOG(ERR, "Failed to set ethdev port %u owner to NULL\n",
> port_id);
> 
> I'm not 100% sure in format, but my requirements are:
>  - log messages should be unique
>  - log messages should be human readable (i.e. I'd avoid
>    usage of function name)
>  - log messages should provide enough information to understand
>    what went wrong and provide context (basically it correlates
>    with uniqueness requirement)
> 
> @Thomas, @Ferruh, what do you think? It would be good if we
> reach an argement before mass changes are done?

I agree with all your comments Andrew.


> > @@ -2491,6 +2515,12 @@ rte_eth_tx_done_cleanup(uint16_t port_id, uint16_t queue_id, uint32_t free_cnt)
> >  	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
> >  	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_done_cleanup, -ENOTSUP);
> >  
> > +	if (queue_id >= dev->data->nb_tx_queues) {
> > +		RTE_ETHDEV_LOG(ERR, "Queue id should be < %u.",
> > +			       dev->data->nb_tx_queues);
> > +		return -EINVAL;
> > +	}
> > +
> 
> I'm not 100% sure that it is a control path.

Indeed it can be used in the data path of some algorithms.