Preheat oven to 400 degrees. Grease and flour two round cake pans.
In a large mixing bowl combine the sugar, eggs, and oil and beat on medium speed with an electric mixer for 2 minutes. Stir in the vanilla.
In a separate bowl sift together the flour, cinnamon, baking soda, and salt.
Slowly add the dry mixture to the wet mixture while beating on low speed with the electric mixer. The batter will be thick.
In a third bowl mash together the bananas and pineapple. Stir in to the batter.
Pour into prepared pans. Bake for 10 minutes at 400 degrees and reduce heat to 350 degrees. Continue baking for 20 - 30 minutes or until toothpick inserted comes out clean.
Cool in pans on wire racks before frosting.
For frosting, using an electric mixer on medium speed beat the butter and cream cheese until well mixed and smooth. Add the vanilla and beat just until combined. Beat in the powdered sugar until smooth.