How to properly use @pytest.mark.foo("bar")

Question

I have three Python files:

file_1.py

@pytest.mark.foo("bar1")
def method_1():
   - code -

file_2.py

@pytest.mark.foo("bar2")
def method_2():
   - code -

file_3.py

@pytest.mark.foo("bar1")
def method_3():
   - code -

How can I run only the files/methods with @pytest.mark.foo("bar1")? I tried to use -m argument, but didn't worked. -k is not recommended since I have a hundred of files mixed with these marks.