[ewg] Issues with ping-pong tests

[Roland Dreier]

 > 1. ibv_ud_pingpong :  doesn't work if size > 2048. I am getting error saying " Failed status 1 for wr_id 2". 
 > For sizes <= 2048, it is working fine. 

Not surprising, since the max UD message size on your system is almost
certainly 2048.  Perhaps the diagnostic could be improved, but I don't
think this is a big deal.

 > 2. -m option of ibv_srq_pingpong doesn't work. The error which we
 > are getting is also not related to MTU. In the man page, there is no
 > mention about this option, but if we do "ibv_srq_pingpong -h", we can
 > see -m option.

There was a missing "break" in the switch statement in srq_pingpong.c
between the 'm' case and the 'q' case, so setting the MTU also
affected the number of QPs.  I checked in a fix.

 > ss23:~ # ibv_srq_pingpong -m 500
 > Segmentation fault

I don't see this failure mode here.  Can you run this under gdb and do
a bt to get a traceback?

 - R.