The leaves have one of the leaf spot diseases, but the worrying issue is the knots on the trunk. Cherry and other trees in the genus Prunus are susceptible to a disease called black knot. You need the advice of a licensed arborist to make a diagnosis and treatment plan. You can find one in your zip code by using the zip code locator on the website of the International Society of Arboriculture. Here is a link to their website.