static bool receive_global(pcu_msg* m)
{
m->received.peer = MPI_ANY_SOURCE;
while ( ! pcu_mpi_receive(&(m->received),pcu_user_comm))
{
if (m->state == send_recv_state)
if (done_sending_peers(m->peers))
{
pcu_begin_barrier(&(m->coll));
m->state = recv_state;
}
if (m->state == recv_state)
if (pcu_barrier_done(&(m->coll)))
return false;
}
return true;
}
/* tries to complete this communication step.
Returns false if communication is not done,
otherwise wraps up communication, merges
if necessary, and returns true */
static bool end_coll_step(pcu_coll* c)
{
int action = c->pattern->action(c->bit);
if (action == pcu_coll_idle)
return true;
if (action == pcu_coll_send)
return pcu_mpi_done(&(c->message));
pcu_message incoming;
pcu_make_message(&incoming);
incoming.peer = c->pattern->peer(c->bit);
if ( ! pcu_mpi_receive(&incoming,pcu_coll_comm))
return false;
if (c->message.buffer.size != incoming.buffer.size)
pcu_fail("collective not called by all ranks or pcu bug");
c->merge(c->message.buffer.start,incoming.buffer.start,incoming.buffer.size);
pcu_free_message(&incoming);
return true;
}