Mavis Staples is the kind of once-in-a-generation artist whose impact on music and culture would be difficult to overstate. She’s both a Blues and a Rock and Roll Hall of Famer, a civil rights icon, a Grammy Award-winner, and a chart-topping soul/gospel/R&B pioneer. A frequent presence at the Filene Center, Staples makes her Barns debut with these special performances between February 21 and 23.