Parents, how much have you told/would you tell your grown children about your own childhood traumas?

It is fairly rare for anyone to make it through to adulthood without some kind of traumatic experience. Some of course are more horrific than others, but most of us seem to come out of our childhood with some lasting scars. My own kids are still too young to even consider sharing tales of my childhood beyond the very basic stuff but I have gotten to wondering about this. How much of your childhood challenges have you shared/would you share with your grown children? Do you think hearing your stories might benefit your children? Might it harm them?