The academic definition of racism is discrimination + power. Meaning, if in Zimbabwe, you are white and are discriminated against, it's racism. If you're black and discriminated against, it'd be discrimination.
If, the same happens in Apartheid era SA, it'd be the other way around. Not that I necessarily buy all of that definition, but that's what's generally accepted in academic circles. So as per that definition, if Inuit are a disadvantaged group in that part of Africa, or if Africans in general are disadvantaged in China, it'd be racism, otherwise it's discrimination.