[OMPI users] How to checkpoint atomic function in OpenMPI

[Nguyen Toan]

Hi all,
I have a MPI program as follows:
-------------------
int main(){
   MPI_Init();
   ......
   for (i=0; i<10000; i++) {
      my_atomic_func();
   }
   ...
   MPI_Finalize();
   return 0;
}
--------------------

The runtime of this program mainly involves in running the loop and
my_atomic_func() takes a little bit long.
Here I want my_atomic_func() to be operated atomically, but the timing of
checkpointing (by running ompi-checkpoint command) may be in the middle of
my_atomic_func() operation and hence ompi-restart may fail to restart
correctly.

So my question is:
+ At the checkpoint time (executing ompi-checkpoint), is there a way to let
OpenMPI wait until my_atomic_func()  finishes its operation?
+ How does ompi-checkpoint operate to checkpoint MPI threads?

Regards,
Nguyen Toan