I am currently trying to model a kind of grill net which is shaped with a curve surface defined by a spline which is revolved around an axis using surface.

This one have holes in a pattern way. Those holes can be done from an extrude features but I need those extrude to be perpendicular/normal to the surface. So far I success to make some holes but they don't follow the curvature of the shape on the curved part.

Any how I can do this ?