1 files changed, 46 insertions, 0 deletions

diff --git a/litmus/Kconfig b/litmus/Kconfig
index 68459d4dca41..48ff3e3c657c 100644
--- a/litmus/Kconfig
+++ b/litmus/Kconfig
@@ -79,6 +79,52 @@ config SCHED_CPU_AFFINITY
 
           Say Yes if unsure.
 
+choice
+        prompt "EDF Tie-Break Behavior"
+        default EDF_TIE_BREAK_LATENESS_NORM
+        help
+          Allows the configuration of tie-breaking behavior when the deadlines
+          of two EDF-scheduled tasks are equal.
+        
+        config EDF_TIE_BREAK_LATENESS
+        bool "Lateness-based Tie Break"
+        help
+          Break ties between to jobs, A and B, based upon the lateness of their
+          prior jobs. The job with the greatest lateness has priority. Note that
+          lateness has a negative value if the prior job finished before its
+          deadline.
+        
+        config EDF_TIE_BREAK_LATENESS_NORM
+        bool "Normalized Lateness-based Tie Break"
+        help
+          Break ties between to jobs, A and B, based upon the lateness, normalized
+          by relative deadline, their prior jobs. The job with the greatest
+          normalized lateness has priority. Note that lateness has a negative value
+          if the prior job finished before its deadline.
+          
+          Normalized lateness tie-breaks are likely desireable over non-normalized
+          tie-breaks if the execution times and/or relative deadlines of tasks in a
+          task set vary greatly.
+        
+        config EDF_TIE_BREAK_HASH
+        bool "Hash-based Tie Breaks"
+        help
+          Break ties between two jobs, A and B, with equal deadlines by using a
+          uniform hash; i.e.: hash(A.pid, A.job_num) < hash(B.pid, B.job_num). Job
+          A has ~50% of winning a given tie-break.
+        
+        config EDF_PID_TIE_BREAK
+        bool "PID-based Tie Breaks"
+        help
+          Break ties based upon OS-assigned process IDs. Use this option if
+          required by algorithm's real-time analysis or per-task response-time
+          jitter must be minimized in overload conditions.
+        
+          NOTES:
+            * This tie-breaking method was default in Litmus 2012.2 and before.
+                
+endchoice
+
 endmenu
 
 menu "Tracing"