( as the calculation of forces is called from the host, and such global functions can call device functions but not other global functions. Device functions can call only other device functions. So it makes it clear where the entry points are from host code. In some OOP-sense, you could consider the device functions to be ``private'', not that I encourage you to think that way.
https://github.com/jzarnett/ece459/blob/master/lectures/L22.tex#L187
( as the calculation of forces is called from the host, and such global functions can call device functions but not other global functions. Device functions can call only other device functions. So it makes it clear where the entry points are from host code. In some OOP-sense, you could consider the device functions to be ``private'', not that I encourage you to think that way.