Infrastructure for Litmus signals.prop/litmus-signals

Added signals to Litmus. Specifcally, SIG_BUDGET signals
are delivered (when requested by real-time tasks) when
a budget is exceeded.

Note: pfair not currently supported (but it probably could be).

1 files changed, 15 insertions, 1 deletions

diff --git a/include/litmus/rt_param.h b/include/litmus/rt_param.h
index 89ac0dda7d3d..637fe6b84f9d 100644
--- a/include/litmus/rt_param.h
+++ b/include/litmus/rt_param.h
@@ -30,9 +30,15 @@ typedef enum {
 typedef enum {
         NO_ENFORCEMENT,      /* job may overrun unhindered */
         QUANTUM_ENFORCEMENT, /* budgets are only checked on quantum boundaries */
-        PRECISE_ENFORCEMENT  /* budgets are enforced with hrtimers */
+        PRECISE_ENFORCEMENT, /* budgets are enforced with hrtimers */
 } budget_policy_t;
 
+typedef enum {
+        NO_SIGNALS,                     /* job receives no signals when it exhausts its budget */
+        QUANTUM_SIGNALS,        /* budget signals are only sent on quantum boundaries */
+        PRECISE_SIGNALS,        /* budget signals are triggered with hrtimers */
+} budget_signal_policy_t;
+
 /* We use the common priority interpretation "lower index == higher priority",
  * which is commonly used in fixed-priority schedulability analysis papers.
  * So, a numerically lower priority value implies higher scheduling priority,
@@ -62,6 +68,7 @@ struct rt_task {
         unsigned int    priority;
         task_class_t    cls;
         budget_policy_t budget_policy; /* ignored by pfair */
+        budget_signal_policy_t budget_signal_policy; /* currently ignored by pfair */
 };
 
 union np_flag {
@@ -118,8 +125,15 @@ struct rt_job {
          * Increase this sequence number when a job is released.
          */
         unsigned int    job_no;
+
+        /* bits:
+         * 0th: Set if a budget exhaustion signal has already been sent for
+         *      the current job. */
+        unsigned long   flags;
 };
 
+#define RT_JOB_SIG_BUDGET_SENT  0
+
 struct pfair_param;
 
 /*      RT task parameters for scheduling extensions