Library rt.model.apa.affinity
Require Import rt.util.all.
Require Import rt.model.apa.job rt.model.apa.task
rt.model.apa.arrival_sequence rt.model.apa.schedule.
(* Definition and properties about processor affinities. *)
Module Affinity.
Import ArrivalSequence ScheduleOfSporadicTask.
Section AffinityDefs.
Variable sporadic_task: eqType.
(* Given the number of processors, ... *)
Variable num_cpus: nat.
(* ... let a processor affinity be a subset of these processors.
Note: notation {set T} is just a list of type T with no duplicates. *)
Definition affinity := {set (processor num_cpus)}.
(* Next, we define a task affinity as the mapping from tasks to affinities. *)
Definition task_affinity := sporadic_task → affinity.
End AffinityDefs.
Section Properties.
Context {sporadic_task: eqType}.
Context {num_cpus: nat}.
Section JobProperties.
(* Assume that each task has a processor affinity alpha. *)
Variable alpha: task_affinity sporadic_task num_cpus.
(* Then, we say that task tsk ...*)
Variable tsk: sporadic_task.
(* ... can execute on processor cpu ...*)
Variable cpu: processor num_cpus.
(* ... iff cpu is part of j's affinity. *)
Definition can_execute_on := cpu ∈ alpha tsk.
End JobProperties.
Section ScheduleProperties.
Context {Job: eqType}.
Variable job_task: Job → sporadic_task.
(* Consider any schedule, ... *)
Context {arr_seq: arrival_sequence Job}.
Variable sched: schedule num_cpus arr_seq.
(* ... and some affinity alpha. *)
Variable alpha: affinity num_cpus.
(* We say that a task is executing on alpha at time t iff it is
scheduled on some processor in that affinity. *)
Definition task_scheduled_on_affinity (tsk: sporadic_task) (t: time) :=
[∃ cpu, (cpu ∈ alpha) ∧ task_scheduled_on job_task sched tsk cpu t].
End ScheduleProperties.
Section Subset.
(* Given two affinities alpha' and alpha, ...*)
Variable alpha' alpha: affinity num_cpus.
(* ... we say that alpha' is subaffinity of alpha iff
alpha' is contained in alpha. *)
Definition is_subaffinity := {subset alpha' ≤ alpha}.
Section Lemmas.
Hypothesis H_subaffinity: is_subaffinity.
Lemma leq_subaffinity : #|alpha'| ≤ #|alpha|.
End Lemmas.
End Subset.
Section IntersectingAffinities.
(* We say that alpha and alpha' intersect iff there exists a processor
that belongs to both affinities. *)
Definition affinity_intersects (alpha alpha': affinity num_cpus) :=
[∃ cpu, (cpu ∈ alpha) ∧ (cpu ∈ alpha')].
End IntersectingAffinities.
End Properties.
End Affinity.
Require Import rt.model.apa.job rt.model.apa.task
rt.model.apa.arrival_sequence rt.model.apa.schedule.
(* Definition and properties about processor affinities. *)
Module Affinity.
Import ArrivalSequence ScheduleOfSporadicTask.
Section AffinityDefs.
Variable sporadic_task: eqType.
(* Given the number of processors, ... *)
Variable num_cpus: nat.
(* ... let a processor affinity be a subset of these processors.
Note: notation {set T} is just a list of type T with no duplicates. *)
Definition affinity := {set (processor num_cpus)}.
(* Next, we define a task affinity as the mapping from tasks to affinities. *)
Definition task_affinity := sporadic_task → affinity.
End AffinityDefs.
Section Properties.
Context {sporadic_task: eqType}.
Context {num_cpus: nat}.
Section JobProperties.
(* Assume that each task has a processor affinity alpha. *)
Variable alpha: task_affinity sporadic_task num_cpus.
(* Then, we say that task tsk ...*)
Variable tsk: sporadic_task.
(* ... can execute on processor cpu ...*)
Variable cpu: processor num_cpus.
(* ... iff cpu is part of j's affinity. *)
Definition can_execute_on := cpu ∈ alpha tsk.
End JobProperties.
Section ScheduleProperties.
Context {Job: eqType}.
Variable job_task: Job → sporadic_task.
(* Consider any schedule, ... *)
Context {arr_seq: arrival_sequence Job}.
Variable sched: schedule num_cpus arr_seq.
(* ... and some affinity alpha. *)
Variable alpha: affinity num_cpus.
(* We say that a task is executing on alpha at time t iff it is
scheduled on some processor in that affinity. *)
Definition task_scheduled_on_affinity (tsk: sporadic_task) (t: time) :=
[∃ cpu, (cpu ∈ alpha) ∧ task_scheduled_on job_task sched tsk cpu t].
End ScheduleProperties.
Section Subset.
(* Given two affinities alpha' and alpha, ...*)
Variable alpha' alpha: affinity num_cpus.
(* ... we say that alpha' is subaffinity of alpha iff
alpha' is contained in alpha. *)
Definition is_subaffinity := {subset alpha' ≤ alpha}.
Section Lemmas.
Hypothesis H_subaffinity: is_subaffinity.
Lemma leq_subaffinity : #|alpha'| ≤ #|alpha|.
End Lemmas.
End Subset.
Section IntersectingAffinities.
(* We say that alpha and alpha' intersect iff there exists a processor
that belongs to both affinities. *)
Definition affinity_intersects (alpha alpha': affinity num_cpus) :=
[∃ cpu, (cpu ∈ alpha) ∧ (cpu ∈ alpha')].
End IntersectingAffinities.
End Properties.
End Affinity.