Chapter 3 Introduction to MR308
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1
Task A
Priority
2
Task C
Task FTask E
Task D
3
n
Task B
Task B
When the priority of task B has been changed from 3 to 1
Figure 3.21 Alteration of task priority
n
Priority 1 Priority 2 Priority 3 Priority 4
When the priority of Task B is changed into 4
1
ID Number
2
taskA
3
taskB
taskC taskB
Figure 3.22 Task rearrangement in a waiting queue
• Reference task priority (get_pri, iget_pri)
Gets the priority of a task.
• Reference task status (simple version) (ref_tst, iref_tst)
Refers to the state of the target task.
• Reference task status (ref_tsk, iref_tsk)
Refers to the state of the target task and its priority, etc.