I never had and certainly would not have worn the famous white roll top jumper but it was very popular, particularly with the air gunners
Reg - I suspect that the famous "white roll top jumper" was almost certainly derived from the equally famous "submarine jersey" (aka "submarine sweater"), dating from WWI or even earlier, recalling a well known Punch cartoon displaying one. I appreciate that it might not have been your garment of choice but they used to be very popular too with the ladies, who would wear them as a (very) short dress, sometimes resorting to stretching them if they were initially too short for their liking!
With very best wishes and hope you are keeping well
Jack
PS I'm pretty sure that the RAF Marine Branch will have worn them too