[ofa-general] [infiniband-diags] add --loop_ports option to perfquery

[Hal Rosenstock]

Hi Al,

On Wed, Oct 8, 2008 at 6:26 AM, Al Chu <chu11 at llnl.gov> wrote:
> Hey Hal,
>
> On Wed, 2008-10-08 at 07:03 -0400, Hal Rosenstock wrote:
>> Al,
>>
>> On Tue, Oct 7, 2008 at 6:54 PM, Al Chu <chu11 at llnl.gov> wrote:
>> > Hey Sasha,
>> >
>> > We have a switch here that does not report the AllPortSelect flag as a
>> > capability.  It's pretty annoying typing each port on the switch or
>> > always having to script around this one oddball switch we have.  So I
>> > added an option --loop_ports for perfquery.  If you want to do something
>> > to all the ports on the CA/Switch, but AllPortSelect isn't available, it
>> > loops through all the available ports instead.
>>
>> Why not add simulated AllPortSelect for multiple ports rather than add
>> another perquery option for this ?
>
> I did try that, and it did seem to work for the switches we had.  But
> when I read the IB spec, it said something to the affect that if a
> system doesn't support AllPortSelect, setting the PortSelect field to
> 0xFF was undefined behavior.

I was suggesting that the emulation support (when AllPortSelect is not
supported) be enhanced for multiple ports and work on both CAs and all
switches. The one difference is one response for AllPortSelect
(whether emulated or not) v. many responses for port loop.

>> > There was already a workaround in the tool for a CA that did not support
>> > the AllPortSelect flag.  I get the feeling the workaround may have been
>> > for a specific hardware, so I kept the workaround in there.
>>
>> > Al
>> >
>> > --
>> > Albert Chu
>> > chu11 at llnl.gov
>> > Computer Scientist
>> > High Performance Systems Division
>> > Lawrence Livermore National Laboratory
>> >
>> > _______________________________________________
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>> > general at lists.openfabrics.org
>> > http:// lists.openfabrics.org/cgi-bin/mailman/listinfo/general
>> >
>> > To unsubscribe, please visit http:// openib.org/mailman/listinfo/openib-general
>> >
>>
>> There are also 2 for loops which are not correct for some switches:
>> for (i = 1; i <= num_ports; i++)
>
> I guess I've never seen a switch that doesn't go from 1 to num_ports.
> Is there something else I need to handle?

Yes, per the spec, enhanced SP0 supports PortCounters. All your
switches likely support AllPortSelect so it's not an issue there.

-- Hal

> Al
>
>> -- Hal
>>
> --
> Albert Chu
> chu11 at llnl.gov
> Computer Scientist
> High Performance Systems Division
> Lawrence Livermore National Laboratory
>
>