Improvements to the GEL Piecewise Linear module: support for arbitrary GEL schedulers in native code and easy max lateness computation.

4 files changed, 27 insertions, 26 deletions

diff --git a/native/include/edf/gel_pl.h b/native/include/edf/gel_pl.h
index d70138a..9902e37 100644
--- a/native/include/edf/gel_pl.h
+++ b/native/include/edf/gel_pl.h
@@ -59,13 +59,8 @@ class GELPl
     };
 
  public:
-   enum Scheduler {
-     GEDF,
-     GFL
-   };
 
-   GELPl(Scheduler sched,
-         unsigned int num_processors,
+   GELPl(unsigned int num_processors,
          const TaskSet& tasks,
          unsigned int rounds);
 
diff --git a/native/include/tasks.h b/native/include/tasks.h
index 0aafa98..092e21a 100644
--- a/native/include/tasks.h
+++ b/native/include/tasks.h
@@ -18,20 +18,23 @@ class Task
     unsigned long period;
     unsigned long wcet;
     unsigned long deadline;
+    unsigned long prio_pt;
 
   public:
 
     /* construction and initialization */
-    void init(unsigned long wcet, unsigned long period, unsigned long deadline = 0);
+    void init(unsigned long wcet, unsigned long period, unsigned long deadline = 0, unsigned long prio_pt = 0);
     Task(unsigned long wcet = 0,
          unsigned long period = 0,
-         unsigned long deadline = 0) { init(wcet, period, deadline); }
+         unsigned long deadline = 0,
+         unsigned long prio_pt = 0) { init(wcet, period, deadline, prio_pt); }
 
     /* getter / setter */
     unsigned long get_period() const { return period;   }
     unsigned long get_wcet() const   { return wcet;     }
     /* defaults to implicit deadline */
     unsigned long get_deadline() const {return deadline; }
+    unsigned long get_prio_pt() const { return prio_pt; }
 
     void set_period(unsigned long period)     { this->period   = period;   }
     void set_wcet(unsigned long wcet)         { this->wcet     = wcet;     }
@@ -156,9 +159,10 @@ class TaskSet
     TaskSet(const TaskSet &original);
     virtual ~TaskSet();
 
-    void add_task(unsigned long wcet, unsigned long period, unsigned long deadline = 0)
+    void add_task(unsigned long wcet, unsigned long period,
+                  unsigned long deadline = 0, unsigned long prio_pt = 0)
     {
-        tasks.push_back(Task(wcet, period, deadline));
+        tasks.push_back(Task(wcet, period, deadline, prio_pt));
     }
 
     unsigned int get_task_count() const { return tasks.size(); }
diff --git a/native/src/edf/gel_pl.cpp b/native/src/edf/gel_pl.cpp
index 89d0177..b058ab1 100644
--- a/native/src/edf/gel_pl.cpp
+++ b/native/src/edf/gel_pl.cpp
@@ -13,7 +13,7 @@ static bool reversed_order(const fractional_t& first,
     return second < first;
 }
 
-GELPl::GELPl(Scheduler sched, unsigned int num_processors, const TaskSet& ts,
+GELPl::GELPl(unsigned int num_processors, const TaskSet& ts,
              unsigned int num_rounds)
 :no_cpus(num_processors), tasks(ts), rounds(num_rounds)
 {
@@ -25,13 +25,13 @@ GELPl::GELPl(Scheduler sched, unsigned int num_processors, const TaskSet& ts,
                sys_utilization.get_num().get_mpz_t(),
                sys_utilization.get_den().get_mpz_t());
     util_ceil = util_ceil_pre.get_ui();
-    std::vector<unsigned long> pps;
+    std::vector<unsigned long> prio_pts;
     fractional_t S = 0;
     std::vector<fractional_t> Y_ints;
 
     int task_count = tasks.get_task_count();
     // Reserve capacity in all vectors to minimize allocation costs.
-    pps.reserve(task_count);
+    prio_pts.reserve(task_count);
     Y_ints.reserve(task_count);
     S_i.reserve(task_count);
     G_i.reserve(task_count);
@@ -43,29 +43,26 @@ GELPl::GELPl(Scheduler sched, unsigned int num_processors, const TaskSet& ts,
         utilizations[i] /= tasks[i].get_period();
     }
     
-    unsigned long min_pp = std::numeric_limits<unsigned long>::max();
+    unsigned long min_prio_pt = std::numeric_limits<unsigned long>::max();
 
     // Compute initial priority points, including minimum.
     for (int i = 0; i < task_count; i++) {
         const Task& task = tasks[i];
-        unsigned long new_pp = task.get_deadline();
-        if (sched == GFL) {
-            new_pp -= ((num_processors - 1) * task.get_wcet()) / num_processors;
-        }
-        pps.push_back(new_pp);
-        if (new_pp < min_pp) {
-            min_pp = new_pp;
+        unsigned long new_prio_pt = task.get_prio_pt();
+        prio_pts.push_back(new_prio_pt);
+        if (new_prio_pt < min_prio_pt) {
+            min_prio_pt = new_prio_pt;
         }
     }
 
     // Reduce to compute minimum.  Also compute Y intercepts, S_i values, and
     // S.
     for (int i = 0; i < task_count; i++) {
-        pps[i] -= min_pp;
+        prio_pts[i] -= min_prio_pt;
         const Task& task = tasks[i];
         unsigned long wcet = task.get_wcet();
         unsigned long period = task.get_period();
-        S_i.push_back(pps[i]);
+        S_i.push_back(prio_pts[i]);
         fractional_t& S_i_i = S_i[i];
         S_i_i *= -1;
         S_i_i /= period;
@@ -102,7 +99,7 @@ GELPl::GELPl(Scheduler sched, unsigned int num_processors, const TaskSet& ts,
         mpz_cdiv_q(xi_ceil.get_mpz_t(),
                    x_i.get_num().get_mpz_t(),
                    x_i.get_den().get_mpz_t());
-        bounds.push_back(pps[i]
+        bounds.push_back(prio_pts[i]
                          + tasks[i].get_wcet()
                          + xi_ceil.get_ui());
         G_i.push_back(s);
diff --git a/native/src/tasks.cpp b/native/src/tasks.cpp
index 0d0624c..409c6d6 100644
--- a/native/src/tasks.cpp
+++ b/native/src/tasks.cpp
@@ -9,8 +9,9 @@
 #include "task_io.h"
 
 void Task::init(unsigned long wcet,
-                unsigned long period,
-                unsigned long deadline)
+                unsigned long period,
+                unsigned long deadline,
+                unsigned long prio_pt)
 {
     this->wcet     = wcet;
     this->period   = period;
@@ -18,6 +19,10 @@ void Task::init(unsigned long wcet,
         this->deadline = period; // implicit
     else
         this->deadline = deadline;
+    if (!prio_pt)
+        this->prio_pt = deadline;
+    else
+        this->prio_pt = prio_pt;
 }
 
 bool Task::has_implicit_deadline() const