Parallel query execution with SPI

Hi hackers,

It is possible to execute query concurrently using SPI?
If so, how it can be enforced?
I tried to open cursor with CURSOR_OPT_PARALLEL_OK flag but it doesn't
help: query is executed by single backend while the same query been
launched at top level uses parallel plan:

fsstate->portal = SPI_cursor_open_with_args(NULL, fsstate->query,
fsstate->numParams, argtypes, values, nulls, true, CURSOR_OPT_PARALLEL_OK);
...
SPI_cursor_fetch(fsstate->portal, true, 1);

Thanks in advance,

--
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company