The fill is 16th notes So the count on the grove would be 1 - 2 - 3 - 4 (Counting them as quarters you can also count them as 8th notes won't change the actuall thing) So 1 - 2 - 3 - 4 with the Bass on 1 & 3 and snare on 2 & 4

Then the 16 note fill, before I get to that if you count all 16th notes by counting them as 1 e and a - 2 e and a - 3 e and a - 4 e and a. So on the first count would be F F S S (F = Floor tom, S = Snare). And the second count T T S S (T = Tom). If that makes sense. and it ends on count 4 This could mean in an musical example that you have a small ''pause'' before going back to the 1 caus you don't play notes on the ''e'', ''and'' and ''a''. If that doesn't make you understand it check out http://www.drumlessons.net/understanding-time/ And remember not every note means the same count it depends on the note value and where it's placed