Library prosa.classic.implementation.global.basic.bertogna_edf_example

Require Import prosa.classic.util.all.
Require Import prosa.classic.model.arrival.basic.job prosa.classic.model.arrival.basic.task prosa.classic.model.priority.
Require Import prosa.classic.model.schedule.global.schedulability.
Require Import prosa.classic.model.schedule.global.basic.schedule prosa.classic.model.schedule.global.basic.platform.
Require Import prosa.classic.analysis.global.basic.workload_bound
               prosa.classic.analysis.global.basic.interference_bound_edf
               prosa.classic.analysis.global.basic.bertogna_edf_comp.
Require Import prosa.classic.implementation.job prosa.classic.implementation.task
               prosa.classic.implementation.arrival_sequence.
Require Import prosa.classic.implementation.global.basic.schedule.
From mathcomp Require Import ssreflect ssrbool ssrnat eqtype seq bigop div.

Module ResponseTimeAnalysisEDF.

  Import Job Schedule SporadicTaskset Priority Schedulability Platform InterferenceBoundEDF WorkloadBound ResponseTimeIterationEDF.
  Import ConcreteJob ConcreteTask ConcreteArrivalSequence ConcreteScheduler.

  Section ExampleRTA.

    Let tsk1 := {| task_id := 1; task_cost := 2; task_period := 5; task_deadline := 3|}.
    Let tsk2 := {| task_id := 2; task_cost := 4; task_period := 6; task_deadline := 5|}.
    Let tsk3 := {| task_id := 3; task_cost := 3; task_period := 12; task_deadline := 11|}.

    (* Let ts be a task set containing these three tasks. *)
    Program Let ts := Build_set [:: tsk1; tsk2; tsk3] _.

    Section FactsAboutTaskset.

      Fact ts_has_valid_parameters:
        valid_sporadic_taskset task_cost task_period task_deadline ts.

      Fact ts_has_constrained_deadlines:
        ∀ tsk,
          tsk \in ts →
          task_deadline tsk ≤ task_period tsk.

    End FactsAboutTaskset.

    (* Assume there are two processors. *)
    Let num_cpus := 2.

    (* Recall the EDF RTA schedulability test. *)
    Let schedulability_test :=
      edf_schedulable task_cost task_period task_deadline num_cpus.

    Fact schedulability_test_succeeds :
      schedulability_test ts = true.
      Ltac f :=
        unfold edf_rta_iteration; simpl;
        unfold edf_response_time_bound, div_floor, total_interference_bound_edf, interference_bound_edf, interference_bound_generic, W; simpl;
        repeat rewrite addnE;
        repeat rewrite big_cons; repeat rewrite big_nil;
        repeat rewrite addnE; simpl;
        unfold num_cpus, divn; simpl.

    (* Let arr_seq be the periodic arrival sequence from ts. *)
    Let arr_seq := periodic_arrival_sequence ts.

    (* Let sched be the work-conserving EDF scheduler. *)
    Let sched := scheduler job_arrival job_cost num_cpus arr_seq
                           (JLFP_to_JLDP (EDF job_arrival job_deadline)).

    (* Recall the definition of deadline miss. *)
    Let no_deadline_missed_by :=
      task_misses_no_deadline job_arrival job_cost job_deadline job_task arr_seq sched.

    (* Next, we prove that ts is schedulable with the result of the test. *)
    Corollary ts_is_schedulable:
      ∀ tsk,
        tsk \in ts →
        no_deadline_missed_by tsk.

  End ExampleRTA.

End ResponseTimeAnalysisEDF.