Re: [PATCH v3] net/tap: fix dev name look-up

[Pascal Mazon <pascal.mazon@6wind.com>]

On Mon, 6 Mar 2017 15:41:14 +0000
Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> On 3/6/2017 3:13 PM, Pascal Mazon wrote:
> > Store the device name in dev->data->name, to have symmetrical
> > behavior between rte_pmd_tap_probe(name) and
> > rte_pmd_tap_remove(name).
> > 
> > The netdevice name (linux interface name) is stored in the name
> > field of struct pmd_internals.
> > 
> > snprintf(data->name) has been moved closer to the
> > rte_ethdev_allocate() as it should use the same name.
> > 
> > Signed-off-by: Pascal Mazon <pascal.mazon@6wind.com>
> > ---
> >  drivers/net/tap/rte_eth_tap.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/net/tap/rte_eth_tap.c
> > b/drivers/net/tap/rte_eth_tap.c index 47a706070652..ece3a5fcc897
> > 100644 --- a/drivers/net/tap/rte_eth_tap.c
> > +++ b/drivers/net/tap/rte_eth_tap.c
> > @@ -663,7 +663,9 @@ eth_dev_tap_create(const char *name, char
> > *tap_name) goto error_exit;
> >  	}
> >  
> > -	dev = rte_eth_dev_allocate(tap_name);
> > +	/* name in allocation and data->name must be consistent */
> > +	snprintf(data->name, sizeof(data->name), "%s", name);
> 
> When you use correct name (name) for rte_eth_dev_allocate(),
> snprintf() no more required. rte_eth_dev_allocate() already does it
> [1].
> 
> [1]
> http://dpdk.org/browse/dpdk/tree/lib/librte_ether/rte_ethdev.c#n230
> 

I disagree here. What rte_eth_dev_allocate() changes, is the shared
automatically-allocated data part, as mentioned in your earlier mail.
We didn't yet pass our own manually allocated data to dev.

Do you see what I mean?

Best regards,
Pascal

> > +	dev = rte_eth_dev_allocate(name);
> >  	if (!dev) {
> >  		RTE_LOG(ERR, PMD, "TAP Unable to allocate device
> > struct\n"); goto error_exit;
> > @@ -691,7 +693,6 @@ eth_dev_tap_create(const char *name, char
> > *tap_name) dev->driver = NULL;
> >  	dev->rx_pkt_burst = pmd_rx_burst;
> >  	dev->tx_pkt_burst = pmd_tx_burst;
> > -	snprintf(dev->data->name, sizeof(dev->data->name), "%s",
> > name); 
> >  	/* Presetup the fds to -1 as being not valid */
> >  	for (i = 0; i < RTE_PMD_TAP_MAX_QUEUES; i++) {
> > 
>