Re: [PATCH v3 1/6] ethdev: fix port data mismatched in multiple process model

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

On Fri, Jan 06, 2017 at 02:12:48PM +0100, Thomas Monjalon wrote:
> 2017-01-06 18:16, Yuanhan Liu:
> > +static void
> > +eth_dev_init(struct rte_eth_dev *eth_dev, uint8_t port_id, const char *name)
> > +{
> > +	eth_dev->data = &rte_eth_dev_data[port_id];
> > +	eth_dev->attached = DEV_ATTACHED;
> > +	eth_dev_last_created_port = port_id;
> > +	nb_ports++;
> > +
> > +	if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
> > +		snprintf(eth_dev->data->name, sizeof(eth_dev->data->name),
> > +			 "%s", name);
> > +		eth_dev->data->port_id = port_id;
> > +	}
> 
> Why not keeping eth_dev->data filling in rte_eth_dev_allocate?

I could do that.

> 
> > +}
> > +
> >  struct rte_eth_dev *
> >  rte_eth_dev_allocate(const char *name)
> >  {
> > @@ -211,12 +226,41 @@ struct rte_eth_dev *
> >  	}
> >  
> >  	eth_dev = &rte_eth_devices[port_id];
> 
> Why not moving this line in eth_dev_init?

Ditto.

> 
> > -	eth_dev->data = &rte_eth_dev_data[port_id];
> > -	snprintf(eth_dev->data->name, sizeof(eth_dev->data->name), "%s", name);
> > -	eth_dev->data->port_id = port_id;
> > -	eth_dev->attached = DEV_ATTACHED;
> > -	eth_dev_last_created_port = port_id;
> > -	nb_ports++;
> > +	eth_dev_init(eth_dev, port_id, name);
> > +
> > +	return eth_dev;
> > +}
> 
> [...]
> > +/*
> > + * Attach to a port already registered by the primary process, which
> > + * makes sure that the same device would have the same port id both
> > + * in the primary and secondary process.
> > + */
> > +static struct rte_eth_dev *
> > +eth_dev_attach_secondary(const char *name)
> 
> OK, good description
> 
> [...]
> > -	eth_dev = rte_eth_dev_allocate(ethdev_name);
> > -	if (eth_dev == NULL)
> > -		return -ENOMEM;
> > +	if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
> > +		eth_dev = rte_eth_dev_allocate(ethdev_name);
> > +		if (eth_dev == NULL)
> > +			return -ENOMEM;
> 
> You could merge here the rest of primary init below.

Oh, right.

> 
> > +	} else {
> > +		eth_dev = eth_dev_attach_secondary(ethdev_name);
> > +		if (eth_dev == NULL) {
> > +			/*
> > +			 * if we failed to attach a device, it means
> > +			 * the device is skipped, due to some errors.
> > +			 * Take virtio-net device as example, it could
> > +			 * due to the device is managed by virtio-net
> > +			 * kernel driver.  For such case, we return a
> > +			 * positive value, to let EAL skip it as well.
> > +			 */
> 
> I'm not sure we need an example here.
> Is the virtio case special?

Not quite sure, likely not. I was thinking a detailed example helps
people to understand better. I could remove it if you think it's
not necessary.

> nit: "it could due" looks to be a typo

Oops.

	--yliu