[mvapich-discuss] wrapping calls to polling functions in MVAPICH2

[Alexander Breslow]

Hi,

I was wondering if there is a single low-level function within MVAPICH2
that implements the polling functionality.  I have seen that polling is
adjustable via the MV2 CM SPIN COUNT environment variable.  My goal is to
be able to time all spinning explicitly.

If this spinning is implemented by a call to a single function F, I would
like to intercept all calls to that function, and redirect those calls to
another function G that times the duration of each invocation of F.

G would be something like the following:

G(args){

t1 = get_time_ns();
F(args);
t2 = get_time_ns();
register(t2,t1);  // Enqueue for post processing

}

This seems feasible via the PMPI interface or by writing a library that
uses DYLD functionality if the spinning/polling function appears in the
symbol table of the respective MVAPICH2 object files.  If this is not
possible, could you please tell me which source files that I would have to
modify in order to achieve what I desire?

Thanks in advance for your time,
Alex
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.cse.ohio-state.edu/pipermail/mvapich-discuss/attachments/20130812/786a5394/attachment.html