I didn't grow up in only China and there as no national policy of anti-religiousness lol. My parents basically left me alone in terms of spiritual matters, they didn't tell me there was a God but they didn't tell me there was no God either. If that qualifies as an atheist upbringing I guess that then I had one. In fact, they felt guilty later that I wasn't taught enough religion and forced me to go to a Christian summer camp for two summers when I was around 10. (I actually didn't catch on that it was a Christian summer camp and wondered the whole time why they kept taking about God)