Minor bug fixes in the QPA implementation

1) On Linux hosts, limits.h must be included explicitly.

2) Don't try to compute the busy interval if the task system
   is over-utilized.

1 files changed, 8 insertions, 5 deletions

diff --git a/native/src/edf/qpa.cpp b/native/src/edf/qpa.cpp
index 23865ca..f138b7c 100644
--- a/native/src/edf/qpa.cpp
+++ b/native/src/edf/qpa.cpp
@@ -2,6 +2,8 @@
 #include <set>
 
 #include <stdlib.h>
+#include <limits.h>
+
 #include "tasks.h"
 #include "math-helper.h"
 #include "stl-helper.h"
@@ -134,16 +136,17 @@ static integral_t get_largest_testpoint(const TaskSet &ts,
 
 bool QPATest::is_schedulable(const TaskSet &ts, bool check_preconditions)
 {
-        integral_t max_interval = edf_busy_interval(ts);
-        unsigned long min_interval = min_relative_deadline(ts);
-
         fractional_t util;
         ts.get_utilization(util);
 
+        if (util > 1)
+                return false;
+
+        integral_t max_interval = edf_busy_interval(ts);
+        unsigned long min_interval = min_relative_deadline(ts);
+
         if (util < 1)
                 max_interval = std::min(max_interval, zhang_burns_interval(ts));
-        else if (util > 1)
-                return false;
 
         integral_t next = get_largest_testpoint(ts, max_interval);
         integral_t demand;