Your cherry tree is suffering from a very common fungal malady that is in a category of 'shot hole' fungus.  The weather conditions this year have been very conducive to a widespread occurrence of this disease on cherry trees.  Fortunately, it is simply a foliar disease and does not kill the tree.  Good sanitation is necessary; rake up and remove all the leaves that fall from the tree this year and hope that the weather conditions next spring are more 'normal'. 
LS