I'm not sure what line you're referring to. There are *no* outright jiffies or msecs in this patch, with the exception of the (3600*HZ) line which is already obvious enough.
The 900000 200001 1900000 1000000 constants are not jiffies nor miliseconds, they're simply numbers, such that 900000/1000000 = 0.9 and 200001/1000000 =~ 0.2 (the +1 is to deal with 0) and 1900000/1000000 = 1.9
