Re: [dpdk-dev] [PATCH v3 1/4] ethdev: increase port_id range

["Yang, Zhiyong" <zhiyong.yang@intel.com>]

> -----Original Message-----
> From: Yigit, Ferruh
> Sent: Wednesday, September 13, 2017 9:33 PM
> To: Thomas Monjalon <thomas@monjalon.net>
> Cc: Yang, Zhiyong <zhiyong.yang@intel.com>; dev@dpdk.org; Doherty, Declan
> <declan.doherty@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>;
> hemant.agrawal@nxp.com; Hunt, David <david.hunt@intel.com>; Richardson,
> Bruce <bruce.richardson@intel.com>; Ananyev, Konstantin
> <konstantin.ananyev@intel.com>
> Subject: Re: [PATCH v3 1/4] ethdev: increase port_id range
> 
> On 9/13/2017 1:18 PM, Thomas Monjalon wrote:
> > 13/09/2017 13:56, Ferruh Yigit:
> >> On 9/13/2017 3:26 AM, Yang, Zhiyong wrote:
> >>> From: Yigit, Ferruh
> >>>> On 9/9/2017 3:47 PM, Zhiyong Yang wrote:
> >>>>> Extend port_id definition from uint8_t to uint16_t in lib and
> >>>>> drivers data structures, specifically rte_eth_dev_data.
> >>>>> Modify the APIs, drivers and app using port_id at the same time.
> >>>>>
> >>>>> Fix some checkpatch issues from the original code and remove some
> >>>>> unnecessary cast operations.
> >>>>>
> >>>>> Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
> >>>>
> >>>> <...>
> >>>>
> >>>>> @@ -283,7 +283,7 @@ enum dcb_mode_enable  #define
> >>>>> MAX_RX_QUEUE_STATS_MAPPINGS 4096 /* MAX_PORT of 32 @ 128
> >>>>> rx_queues/port */
> >>>>>
> >>>>>  struct queue_stats_mappings {
> >>>>> -	uint8_t port_id;
> >>>>> +	uint16_t port_id;
> >>>>
> >>>> Can this be "portid_t port_id;" ? For testpmd, portid_t can be used
> >>>> for all port_id declarations.
> >>>>
> >>>
> >>> Ferruh, the suggestion has been discussed in the following thread.
> >>> Most of people agree on The basic type uint16_t. :).  Your suggestion was
> my preference  previously.
> >>> At last, I make this decision to use uint16_t.  You know, whatever I
> >>> use, some ones will stand out and Say the other is better.  :)
> >>> http://www.dpdk.org/dev/patchwork/patch/23208/
> >>
> >> This discussion was whole dpdk, my comment is for testpmd only.
> >>
> >> Testpmd already defines "portid_t" and uses it in many places [1]. I
> >> am saying why keep using "uint16_t" in some places in testpmd? Lets
> >> switch all to "portid_t" while we are touching them all.
> >>
> >> [1]
> >>   -typedef uint8_t  portid_t;
> >>   +typedef uint16_t portid_t;
> >
> > Or the reverse, we can drop portid_t from testpmd, especially if it is
> > not used everywhere in testpmd.
> > Note: this typedef hides the size of the port, which may be important
> > when optimizing code.
> 
> No strong opinion about keeping "uint16_t" or "portid_t", "portid_t" is already in
> use, not sure if worth the effort to remove it.
> 
> But I am for unifying the storage type used, one or other.

Think again. If basic type can bring the benefit as Thomas said, we may consider to use uint16_t instead of portid_t in testpmd. 

Zhiyong