Javascript: # of steps it takes to execute naive(a, b) as a function of 'a'

gistfile1.js

var naive = function (a, b) {
    var x = a;  // 1 unit
    var y = b;  // 1 unit
    var z = 0;  // 1 unit
    while (x > 0) { // runs twice
        z = z + y;
        x = x - 1;
        return z;
    }
};

var time = function (a) {
    /* # of steps it takes to execute naive(a, b) as a function of 'a' */
    return 2*a + 3;   
};

var naiveTest = naive(10,5);
var timeTest = time(10);
console.log('Naive test: ' + naiveTest + ' && Time test: ' + timeTest);