What is the test for reasonable use of force under the Fourth Amendment?

Moreover, "[a]n action is 'reasonable' under the Fourth Amendment, regardless of the individual officer's state of mind, 'as long as the circumstances, viewed objectively, justify [the] action.' [Citation.] The officer's subjective motivation is irrelevant. [Citations.]" (Brigham City, Utah v. Stuart (2006) 547 U.S. 398, 404-405.) "[T]he Fourth Amendment's concern with 'reasonableness' allows certain actions to be taken in certain circumstances, whatever the subjective intent. [Citations.]" (Whren v. United States (1996) 517 U.S. 806, 814.)