Re: [dpdk-dev] [PATCH v8] app/testpmd: add portlist option

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

> -----Original Message-----
> From: Burakov, Anatoly <anatoly.burakov@intel.com>
> Sent: Tuesday, February 11, 2020 4:52 PM
> To: Govindharajan, Hariprasad <hariprasad.govindharajan@intel.com>; Lu,
> Wenzhuo <wenzhuo.lu@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>;
> Iremonger, Bernard <bernard.iremonger@intel.com>; Mcnamara, John
> <john.mcnamara@intel.com>; Kovacevic, Marko
> <marko.kovacevic@intel.com>
> Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yigit@intel.com>;
> stephen@networkplumber.org; david.marchand@redhat.com
> Subject: Re: [dpdk-dev] [PATCH v8] app/testpmd: add portlist option
> 
> On 11-Feb-20 3:52 PM, Hariprasad Govindharajan wrote:
> > In current version, we are setting the ports using portmask. With
> > portmask, we can use only upto 64 ports. This portlist option enables
> > the user to use more than 64 ports.
> > Now we can specify the ports in 2 different ways
> >   - Using portmask (-p [0x]nnn): mask must be in hex format
> >   - Using portlist in the following format
> >   --portlist <p1>[-p2][,p3[-p4],...]
> >
> >   --portmask 0x2 is same as --portlist 1
> >   --portmask 0x3 is same as --portlist 0-1
> >
> > Signed-off-by: Hariprasad Govindharajan
> > <hariprasad.govindharajan@intel.com>
> > ---
> > v8:
> > changed the data types of the variables.
> > optimised the code by checking for blank spaces only once.
> >
> > v7:
> > moved the port validation outside the parser function.
> > added meaningful comments describing the new functionality.
> > renamed the variables with meaningful names
> >
> > v6:
> > optimized the code to check for duplicates
> >
> > v5:
> > added a check to validate the ports available before setting them.
> > also added comments in the testpmd file for the new function
> >
> > v4:
> > the parser is modified so that we don't ues 2 arrays to convert the
> > listed port values
> >
> > v3:
> > squashed the 2 patches and made it 1 patch with changes only in
> > testpmd. Also working on optmizing the parser
> >
> > v2:
> > moved the parser function to testpmd
> > ---
> >   app/test-pmd/config.c                 | 108
> ++++++++++++++++++++++++++++++++++
> >   app/test-pmd/parameters.c             |   5 ++
> >   app/test-pmd/testpmd.h                |   3 +
> >   doc/guides/testpmd_app_ug/run_app.rst |   7 +++
> >   4 files changed, 123 insertions(+)
> >
> > diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c index
> > 9669cbd..86566d9 100644
> > --- a/app/test-pmd/config.c
> > +++ b/app/test-pmd/config.c
> > @@ -2587,6 +2587,114 @@ set_fwd_ports_list(unsigned int *portlist,
> unsigned int nb_pt)
> >   	}
> >   }
> >
> > +/**
> > + * Parse the user input and obtain the list of forwarding ports
> > + *
> > + * @param[in] list
> > + *   String containing the user input. User can specify
> > + *   in these formats 1,3,5 or 1-3 or 1-2,5 or 3,5-6.
> > + *   For example, if the user wants to use all the available
> > + *   4 ports in his system, then the input can be 0-3 or 0,1,2,3.
> > + *   If the user wants to use only the ports 1,2 then the input
> > + *   is 1,2.
> > + *   valid characters are '-' and ','
> > + *   invalid chars like '.' or '#' will result in
> > + *   EAL: Error - exiting with code: 1
> > + *     Cause: Invalid fwd port list
> > + * @param[out] values
> > + *   This array will be filled with a list of port IDs
> > + *   based on the user input
> > + *   Note that duplicate entries are discarded and only the first
> > + *   count entries in this array are port IDs and all the rest
> > + *   will contain default values
> > + * @param[in] maxsize
> > + *   This parameter denotes 2 things
> > + *   1) Maximum size of the values array
> > + *   2) Maximum value of each element in the values array
> 
> I still suspect the first item should say "number", not size. The 2) takes care of
> how big each individual value is, and 1) presumably takes care of how many
> of these values there can be. Therefore i think it should be "number" (as in
> how many), not "size" (as in how big).
> 

[Govindharajan, Hariprasad]  Changed
> > + * @return
> > + *   -returns total count of parsed port IDs
> > + */
> > +static unsigned int
> > +parse_port_list(const char *list, unsigned int *values, unsigned int
> > +maxsize) {
> > +	unsigned int count = 0;
> > +	char *end = NULL;
> > +	int min, max;
> > +	int value, i;
> > +	unsigned int marked[maxsize];
> > +
> > +	if (list == NULL || values == NULL)
> > +		return -1;
> > +
> > +	for (i = 0; i < (int)maxsize; i++)
> > +		marked[i] = 0;
> 
> Then memset(), but that's just nitpicking, so feel free to disregard :)

[Govindharajan, Hariprasad] It is disregarded.. 😊
> 
> > +
> > +	min = INT_MAX;
> > +
> > +	do {
> > +		/*Remove the blank spaces if any*/
> > +		while (*list != '\0' && isblank(*list))
> > +			list++;
> 
> My apologies. I've just checked if isblank() returns 0 on '\0', and it does. So,
> the `*list != '\0'` check is not necessary here after all.

[Govindharajan, Hariprasad] Removed the isblank check
> 
> > +		if (*list == '\0')
> > +			break;
> > +		errno = 0;
> > +		value = strtol(list, &end, 10);
> > +		if (errno || end == NULL)
> > +			return 0;
> > +		if (value < 0 || value >= (int)maxsize)
> > +			return 0;
> > +		while (isblank(*end))
> > +			end++;
> > +		if (*end == '-') {
> > +			min = value;
> 
> This would accept input such as "1-2-3" and parse it as "2-3". Maybe
> 
> if (*end == '-' && min == INT_MAX)
> 
> ? This would then fall through to the failure path if end was '-' and min was
> already set.
>
[Govindharajan, Hariprasad] corrected.
> 
> --
> Thanks,
> Anatoly