Chapter 5. Delaying Execution
Often, drivers need to delay their execution in order to give their device(s), the kernel, or a user the time to accomplish some task. In this chapter, I’ll detail the different functions available for achieving these delays. In the process, I’ll also describe asynchronous code execution.
Voluntary Context Switching, or Sleeping
Voluntary context switching, or sleeping, is done when a driver thread must await the availability of a resource or the arrival of an event; for example, a driver thread should sleep after it requests data from an input device, such as a terminal (McKusick and Neville-Neil, 2005). A driver thread ...
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