Fastest way to call a kernel-mode device driver function? RRS feed

  • Question

  • I have a real-time, timing sensitive device-driver.   From user-mode application, what is fastest way to call a kernel-mode device driver function?


    Thursday, November 30, 2017 4:26 PM

All replies

  • That is a pretty open ended question.   What kind of response time are you looking for?   What is the size of the parameters you need to pass to the function and what is the size of the return value?

    There are a lot of ways to provide a very quick path between user space and the kernel, but you also need to remember Windows is not real time, so there is a possibility some other operation is going to impact your performance.   Tell us more about what you are doing, and we can give you suggestions.

    Don Burn Windows Driver Consulting Website: http://www.windrvr.com

    Thursday, November 30, 2017 4:43 PM
  • If you already have a device driver, and that device driver was intended to be called from user-mode, then you have to use the method they designed in.  There must be documentation somewhere that tells you how to find and call into the driver.

    If you are about to create such a driver, then Don's answer is the right one.

    Tim Roberts, Driver MVP Providenza & Boekelheide, Inc.

    Wednesday, December 6, 2017 11:16 PM