What is the distinction between being a social justice warrior and a reasonable level of speaking out against discrimination?

When I say speaking out against discrimination I am referring to discrimination all across the board. Be it based on gender / gender identity, sexuality, race, culture, religion etc.

For this question I cannot define social justice warrior, because quite frankly I’m not entirely sure if there is a single consistent definition. I believe this has caused quite a bit of confusion. So please feel free to offer an explanation of “social justice warrior” or “white knight” within your answer.