This commit changes the behavior of bml/r2 from conditionally
registering btl progress functions to always registering progress
functions. Any progress function beloning to a btl that is not yet in
use is registered as low-priority. As soon as a proc is added that
will make use of the btl is is re-registered normally.
This works around an issue with some btls. In order to progress a
first message from an unknown peer both ugni and openib need to have
their progress functions called. If either btl is not in use after the
first call to add_procs the callback was never happening. This commit
ensures the btl progress function is called at some point but the
number of progress callbacks is reduced from normal to ensure lower
overhead when a btl is not used. The current ratio is 1 low priority
progress callback for every 8 calls to opal_progress().
Fixesopen-mpi/ompi#1676
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
a679cc072b