Re: [dpdk-dev] [PATCH v3 6/7] app/proc-info: provide way to request info on owned ports

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 10 May 2022 14:39:05 +0530
Subendu Santra <subendu@arista.com> wrote:

> Hi Stephen, Thomas,
> 
> On a related note w.r.to commit 1dd6cffb6571f816d5a0d1fd620f43532240b40b
> (app/procinfo: provide way to request info on owned ports), we see this
> change:
> 
> -static uint32_t enabled_port_mask;
> > +static unsigned long enabled_port_mask;  
> 
> 
> While this is ok for 64-bit machines, where unsigned long is 64-bit, on
> 32-bit machines unsigned long is 32-bits.
> Should we change this to unsigned long long which is guaranteed to be
> 64-bits on both architectures?
> 
> Specifying a mask of 0xffffffffffffffff on 32-bit platforms results in
> error:
> 
> > + sudo /usr/share/dpdk/tools/dpdk-procinfo -- --show-port -p
> > 0xffffffffffffffff
> > Invalid portmask '0xffffffffffffffff'  
> 
> 
> We have a script that runs periodically and it uses the dpdk-procinfo tool
> to collect information about the ports.
> It will be ideal to use the same portmask in the script irrespective of the
> platform it runs on.
> 
> Kindly share your thoughts on this.
> 
> Regards,
> Subendu.
> 
> 
> 
> On Wed, May 4, 2022 at 11:18 PM Stephen Hemminger <
> stephen@networkplumber.org> wrote:  
> 
> > On Tue, 03 May 2022 10:47:58 +0200
> > Thomas Monjalon <thomas@monjalon.net> wrote:
> >  
> > > 24/04/2022 07:34, Subendu Santra:  
> > > > Hi Stephen,
> > > >
> > > > We were going through the patch set:  
> > https://inbox.dpdk.org/dev/20200715212228.28010-7-stephen@networkplumber.org/
> > and hoping to get clarification on the behaviour if post mask is not
> > specified in the input to `dpdk-proc-info` tool.  
> > > >
> > > > Specifically, In PATCH v3 6/7, we see this:
> > > > +   /* If no port mask was specified, one will be provided */
> > > > +   if (enabled_port_mask == 0) {
> > > > +           RTE_ETH_FOREACH_DEV(i) {
> > > > +                   enabled_port_mask |= 1u << i;
> > > >
> > > > However, in PATCH v4 8/8, we see this:
> > > > +   /* If no port mask was specified, then show non-owned ports */
> > > > +   if (enabled_port_mask == 0) {
> > > > +           RTE_ETH_FOREACH_DEV(i)
> > > > +                   enabled_port_mask = 1ul << i;
> > > > +   }
> > > >
> > > > Was there any specific reason to show just the last non-owned port in  
> > case the port mask was not specified?  
> > > > Should we show all non-owned ports in case the user doesn’t specify  
> > any port mask?  
> > >
> > > It looks like a bug. It should be |=
> > > Feel free to send a fix.
> > >
> > >  
> >
> > Agree. Thats a bug.
> >
> > It would be good to have a "show all ports" flag to proc-info.
> > To show all ports including owned.
> >  

Using uint64_t is better, but eventually many DPDK utilities need to be
fixed to handle > 64 ports.