Allocate background slack for idle CPU time.

Fix this. This is a fairly large hack.

1 files changed, 19 insertions, 7 deletions

diff --git a/litmus/sched_edf_hsb.c b/litmus/sched_edf_hsb.c
index fcad1072632a..d89364fdb582 100644
--- a/litmus/sched_edf_hsb.c
+++ b/litmus/sched_edf_hsb.c
@@ -49,6 +49,7 @@
 #define BE_PROC_NAME    "be_servers"
 #define HRT_PROC_NAME   "hrt_servers"
 #define BE_SERVER_BASE  100
+#define IDLE_SLACK_BASE 1000
 #define SLACK_MIN       NSEC_PER_MSEC
 
 /* SCHED_TRACE action events */
@@ -371,6 +372,10 @@ static noinline void check_donate_slack(server_t *donator, struct task_struct *w
         donate_slack(donator);
 }
 
+#else
+#define check_donate_slack(a, b)
+#endif
+
 /*
  * Adds the task to the candidate queue if it is eligible for slack stealing.
  */
@@ -432,13 +437,6 @@ static noinline struct task_struct* next_eligible_slack(void)
         return next;
 }
 
-#else
-#define check_donate_slack(a, b)
-#define check_slack_candidate(a)
-#define next_eligible_slack_server() (NULL)
-#define next_eligible_slack() (NULL)
-#endif
-
 /*
  * Order BE tasks FIFO.
  */
@@ -660,6 +658,9 @@ static void reclaim_slack(server_t *slack)
         lt_t exec;
         server_t *donator = server_slack(slack);
 
+        if (!donator)
+                return;
+
         /* SRT servers do not ever reclaim slack */
         sched_trace_action(NULL, SLACK_RECLAIM_ACTION);
 
@@ -2413,6 +2414,7 @@ static int __init init_edf_hsb(void)
 {
         cpu_entry_t    *entry;
         hrt_server_t   *hrt_server;
+        server_t       *idle_slack;
         int rv, cpu;
 
         rv = register_sched_plugin(&edf_hsb_plugin);
@@ -2461,6 +2463,16 @@ static int __init init_edf_hsb(void)
                 entry      = &per_cpu(cpu_entries, cpu);
                 hrt_server = &entry->hrt_server;
 
+                idle_slack = server_alloc(GFP_ATOMIC);
+                server_init(idle_slack, &server_domain,
+                            IDLE_SLACK_BASE + cpu,
+                            ULLONG_MAX, ULLONG_MAX, 1);
+                idle_slack->deadline = ULLONG_MAX;
+                idle_slack->budget = ULLONG_MAX;
+                idle_slack->job_no = 1;
+                idle_slack->release = 1;
+                add_slack(idle_slack);
+
                 entry->cpu = cpu;
                 entry->linked = NULL;
                 entry->scheduled = NULL;