path: root/testsuites/smptests/smpcapture01/smpcapture01.doc

This file describes the directives and concepts tested by this test set.

test set name: smpcapture01

directives:
  rtems_capture_open
  rtems_capture_watch_ceiling
  rtems_capture_watch_floor
  rtems_capture_watch_global
  rtems_capture_set_trigger
  rtems_capture_control
  rtems_capture_print_trace_records


concepts:

This test does a worst case migration of 4 tasks on a 4 core system tracking
and displaying the user extension records. This task is rather complex to
describe but using the notation TaskName:Priority:{cpu,cpu} where the third
portion indicates the CPUs the task has affinity for. The test starts with
the initialization task (UT1:7:{2,3}) starting execution on CPU 3. This
results in the following tasks assigned across the CPUs:

     CPUs 0-2: Idle threads
     CPU 3: UT1

The UT1 task creates four more tasks as follows:
     TA1:8:{2,3}
     TA2:5:{0,1}
     TA3:6:{0,3}
     TA4:9:{1}

This should result in the tasks being assigned to CPUs as follows:
     CPU 0: TA3
     CPU 1: TA2
     CPU 2: TA1
     CPU 3: UT1

TA4 should be ready to execute but waiting on a CPU it has affinity for
to become available.  The test then raises the priority of TA4 to 4,
resulting in the tasks being assigned to CPUs as follows:
     CPU 0: TA2
     CPU 1: TA4
     CPU 2: UT1
     CPU 3: TA3

At this point TA1 should still be ready to execute but is waiting on a CPU
it has affinity for to become available.  The tasks are then terminated.
Additionally, the capture engine output shows that the migration that can
occur during task termination adheres to the affinity settings.