SWP_SYNCHRONOUS_IO
if (data_race(si->flags & SWP_SYNCHRONOUS_IO))
if (data_race(si->flags & SWP_SYNCHRONOUS_IO)) {
else if (data_race(sis->flags & SWP_SYNCHRONOUS_IO))
bool synchronous = sis->flags & SWP_SYNCHRONOUS_IO;
if (data_race(si->flags & SWP_SYNCHRONOUS_IO)) {
si->flags |= SWP_SYNCHRONOUS_IO;