Commented bugs, TODO's and things that are (at least for me) unclear

kernel/sched/pb.c

@@ -122,9 +122,15 @@ static struct task_struct * pick_next_task_pb(struct rq *rq,
 	if (next_mode == PB_EXEC_MODE)
 	{
 		if (current_mode == PB_EXEC_MODE){
-			int perf_counter = terminate_perf_event(pb->pevent, pb->plan[pb->c_entry].task_id);
+			/*
+			 * !!! perf_counter contains return value of perf_event_release_kernel(), not the event counter !!!
+			 */
+			// u64 pevent_cntval;
+			int perf_counter = terminate_perf_event(pb->pevent, pb->plan[pb->c_entry].task_id /*, &pevent_cntval */);
 			//error detection
+
 			if (perf_counter < pb->plan[pb->c_entry].n_instr){
+			// if (pevent_cntval < pb->plan[pb->c_entry].n_instr){
 				printk(KERN_WARNING "PB TASK %llu RAN TOO SHORT\n",pb->plan[pb->c_entry].task_id);
 			}
 			pb->c_entry++;
@@ -143,7 +149,7 @@ static struct task_struct * pick_next_task_pb(struct rq *rq,
 			}
 		}else if(current_mode == PB_ADMIN_MODE){
 			printk(KERN_DEBUG "PB ADMIN,STOP,%u,%llu\n", pb->c_entry, sched_clock());
-		}else{
+		}else{	// PB_DISABLED_MODE
 			int perf_init_res = init_perf_event(pb->plan[pb->c_entry], &pb->pevent);
 
 			if(perf_init_res < 0){
@@ -177,7 +183,9 @@ static void set_curr_task_pb(struct rq *rq)
 	// NOP
 }
 
-
+/*
+ * TODO: Make sure this does't interrupt determine_next_mode_pb() and pick_next_task_pb()
+ */
 static void task_tick_pb(struct rq *rq, struct task_struct *p, int queued)
 {
 	int next_mode;

kernel/sched/perf_error_detection.c

@@ -3,6 +3,15 @@
 
 #define PERF_SAMPLE_PERIOD_SIZE		100000
 
+/*
+ * Our understanding of perf so far. Please correct as needed.
+ *
+ * An event in perf's terms is an instruction in our case.
+ * A sample is a fixed number of events that CAN trigger a wakeup_event (but not the only way).
+ * An overflow event is triggered by a fixed number of wakeup_event.
+ *
+ */
+
 //initialize perf event for new task
 int init_perf_event(struct plan_entry plan_entry, struct perf_event **pevent){
 	struct perf_event_attr pe;
@@ -34,8 +43,14 @@ int init_perf_event(struct plan_entry plan_entry, struct perf_event **pevent){
 }
 
 //terminate perf event - return performance counter value
-long long terminate_perf_event(struct perf_event *pevent, u64 task_id){
-
+/*
+ * TODO: return the event counter value
+ *
+ */
+long long terminate_perf_event(struct perf_event *pevent, u64 task_id /*, u64 *pevent_cntval */){
+
+	// TODO:
+	// *pevent_cntval = get the counter value here
 	return perf_event_release_kernel(pevent);
 
 }

kernel/sched/sched.h

@@ -537,7 +537,7 @@ struct pb_rq {
 	// currently executed entry of the plan
 	unsigned int c_entry;
 	// pointer to the dummy task
-	struct task_struct *proxy_task;
+	struct task_struct *proxy_task;			//TODO: We should comment this out and iterate the plan accordingly
 
 	// amount of timer consecutive timer interrupts for pb tasks
 	u64 n_pb_cycles;
@@ -552,6 +552,8 @@ struct pb_rq {
 	// one of PB_DISABLED_MODE, PB_EXEC_MODE, PB_ADMIN_MODE
 	int mode;
 
+
+	//TODO: Do we still need those?
 	int measure_k;
 	u64 kstart;
 	u64 ktime;
@@ -881,6 +883,11 @@ static inline int determine_next_mode_pb(struct rq *rq)
 	{
 		// initial switch
 		if (pb->mode == PB_DISABLED_MODE &&
+				//TODO:
+				/*
+				 * We have to iterate the Plan, and think about a mechanism to signal that a plan is ready
+				 * to be processed - maybe set pb->size 0 when the plan is done, n when a plan with n entries is ready.
+				 */
 				pb->proxy_task != NULL)
 		{
 			return PB_EXEC_MODE;
@@ -890,6 +897,9 @@ static inline int determine_next_mode_pb(struct rq *rq)
 			if (pb->mode == PB_EXEC_MODE)
 			{
 				//stay for n timer interrupts cycles in exec mode
+				/*
+				 * Is the tick interrupt active in this moment?
+				 */
 				if(pb->count_pb_cycles > pb->n_pb_cycles){
 					mode = PB_ADMIN_MODE;
 					pb->count_pb_cycles = 0;
@@ -900,6 +910,9 @@ static inline int determine_next_mode_pb(struct rq *rq)
 			else if (pb->mode == PB_ADMIN_MODE)
 			{
 				//stay for n timer interrupt cylces in uall mode for admin tasks
+				/*
+				 * Is the tick interrupt active in this moment?
+				 */
 				if(pb->count_admin_cycles > pb->n_admin_cycles){
 					mode = PB_EXEC_MODE;
 					pb->count_admin_cycles = 0;