Enforcing schedulability of multi-task systems by hardware-software codesign

This paper deals with the problem of hardware-software codesign of hard real-time systems. For a given task set, we perform an exact schedulability test to determine whether the task set is schedulable or not. When there is a task that cannot meet the deadline, we compute the amount of time by which the deadline is missed. Then we determine which tasks should reduce their execution time to compensate that amount of time deviation. The reduction of execution time is achieved by implementing parts of the tasks with hardware. With this approach, we can systematically design a hard real-time system which is infeasible with all software implementation. Preliminary experimental results are given to demonstrate the effectiveness of our approach.