Re: [RFC 2/9] ethdev: move queue id check in generic layer

[Olivier Matz <olivier.matz@6wind.com>]

Hi Ferruh,

On Thu, 2016-11-24 at 10:59 +0000, Ferruh Yigit wrote:
> On 11/24/2016 9:54 AM, Olivier Matz wrote:
> > The check of queue_id is done in all drivers implementing
> > rte_eth_rx_queue_count(). Factorize this check in the generic
> > function.
> > 
> > Note that the nfp driver was doing the check differently, which
> > could
> > induce crashes if the queue index was too big.
> > 
> > By the way, also move the is_supported test before the port valid
> > and
> > queue valid test.
> > 
> > PR=52423
> > Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> > Acked-by: Ivan Boule <ivan.boule@6wind.com>
> > ---
> 
> <...>
> 
> > diff --git a/lib/librte_ether/rte_ethdev.h
> > b/lib/librte_ether/rte_ethdev.h
> > index c3edc23..9551cfd 100644
> > --- a/lib/librte_ether/rte_ethdev.h
> > +++ b/lib/librte_ether/rte_ethdev.h
> > @@ -2693,7 +2693,7 @@ rte_eth_rx_burst(uint8_t port_id, uint16_t
> > queue_id,
> >   *  The queue id on the specific port.
> >   * @return
> >   *  The number of used descriptors in the specific queue, or:
> > - *     (-EINVAL) if *port_id* is invalid
> > + *     (-EINVAL) if *port_id* or *queue_id* is invalid
> >   *     (-ENOTSUP) if the device does not support this function
> >   */
> >  static inline int
> > @@ -2701,8 +2701,10 @@ rte_eth_rx_queue_count(uint8_t port_id,
> > uint16_t queue_id)
> >  {
> >  	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
> >  
> > -	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
> >  	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_count,
> > -ENOTSUP);
> > +	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
> 
> Doing port validity check before accessing dev->dev_ops-
> >rx_queue_count
> can be good idea.
> 
> What about validating port_id even before accessing
> rte_eth_devices[port_id]?
> 

oops right, we should not move this line, it's stupid...

Thanks for the feedback,
Olivier