Re: [dpdk-dev] [PATCH 2/2] eal: add eal_parse_optionlist to parse user input

["Govindharajan, Hariprasad" <hariprasad.govindharajan@intel.com>]

> -----Original Message-----
> From: Stephen Hemminger <stephen@networkplumber.org>
> Sent: Wednesday, January 29, 2020 7:20 PM
> To: Yigit, Ferruh <ferruh.yigit@intel.com>
> Cc: David Marchand <david.marchand@redhat.com>; Thomas Monjalon
> <thomas@monjalon.net>; Govindharajan, Hariprasad
> <hariprasad.govindharajan@intel.com>; dev <dev@dpdk.org>
> Subject: Re: [dpdk-dev] [PATCH 2/2] eal: add eal_parse_optionlist to parse
> user input
> 
> On Wed, 29 Jan 2020 18:07:05 +0000
> Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> 
> > On 1/29/2020 5:44 PM, David Marchand wrote:
> > > On Tue, Jan 28, 2020 at 6:35 PM Ferruh Yigit <ferruh.yigit@intel.com>
> wrote:
> > >> On 1/27/2020 10:30 AM, Hariprasad Govindharajan wrote:
> > >>> In current version, there is a function which parses the corelist
> > >>> based on user value. A new generic function eal_parse_optionlist
> > >>> is added which will parse corelist as well as similar user input
> > >>> so that we can use it as a public API too.
> > >>>
> > >>> Signed-off-by: Hariprasad Govindharajan
> > >>> <hariprasad.govindharajan@intel.com>
> > >>
> > >> Hi David,
> > >>
> > >> Overall this patchset is to add '--portlist' command to testpmd and
> > >> remove existing 64 port limitation.
> > >>
> > >> And in this patch re-uses the exiting parser function in eal and
> > >> converts it to API, question is if eal is good place to have this API, what
> do you think about it?
> > >
> > > Exporting string parsers from the EAL has little value.
> > > Ok we avoid code duplication (and I can see other places in the tree
> > > where it might be used), but in the end we will have to maintain
> > > this API in the ABI when it enters the stable ABI.
> > >
> > > I am for avoiding this.
> > >
> > >
> >
> > The same function can be used in some sample applications too (which
> > are using port mask), so instead of duplicating it multiple times, it
> > would be nice to have this function somewhere that applications can use.
> >
> > Does it makes sense to have a rte_util.c (under in eal or as a
> > separate library) to have this kind of application helper functions?
> 
> It makes sense to have a rte library that handles arbitrary size bitvector and
> has string handling functions. Kind of like what kernel has for the cpuset
> parsing.  This could be used for cpus in EAL and port-masks or other arrays in
> applications.
> 
> But just doing copy/paste of existing code without thinking about how API
> should work is a bad idea.

[Govindharajan, Hariprasad] 
Hi,

PLEASE IGNORE MY PREVIOUS EMAIL.

I am planning to move the existing parser function to the testpmd file instead of keeping it in the eal and will revert the eal back.

Also, I am planning to create an util file in eal with this parser and do a RFC.

@Stephen Hemminger, We already investigated the existing function and then decided to re-use it as seen in the patch. For creating an API, is there any other specific requirements that should be addressed? Please clarify us.

Thanks
G Hariprasad