I would like to create my own service with global visibility. To implement that, I followed this sample solution.
Everything goes well, I can call my service within a cla
You should use MEF to composes services for your extensions; not the old COM-based ServiceProvider stuff.
Put all of your actual code in MEF-exported classes, then invoke them from the package class using the SComponentModel service.
SComponentModel
For more information, see my blog.