Modify the systemtap perf sampling internal api

The only information available in the overflow interrupt is the event.
Need to group other pieces of information needed by systemtap, so they
can be found based on the the location of the event information.

2 files changed, 31 insertions, 20 deletions

diff --git a/runtime/perf.c b/runtime/perf.c
index 06ed551a..7f1aaf74 100644
--- a/runtime/perf.c
+++ b/runtime/perf.c
@@ -25,27 +25,29 @@
  *
  * @param attr description of event to sample
  * @param callback function to call when perf event overflows
+ * @param pp associated probe point
+ * @param ph probe handler
  */
-static Perf _stp_perf_init (struct perf_event_attr *attr,
-			    perf_overflow_handler_t callback)
+static Perf *_stp_perf_init (struct perf_event_attr *attr,
+			     perf_overflow_handler_t callback,
+			     const char *pp, void (*ph) (struct context *) )
 {
 	int cpu;
-	Perf pe;
+	Perf *pe;
 
-	pe = (Perf) _stp_kmalloc (sizeof(struct _Perf));
+	pe = (Perf *) _stp_kmalloc (sizeof(Perf));
 	if (pe == NULL)
 		return NULL;
-	pe->callback = callback;
 
 	/* allocate space for the event descriptor for each cpu */
-	pe->pd = (struct perf_event **)
-		_stp_alloc_percpu (sizeof(struct perf_event *));
+	pe->pd = (perfcpu *) _stp_alloc_percpu (sizeof(perfcpu));
 	if (pe->pd == NULL)
 		goto exit1;
 
 	/* initialize event on each processor */
 	stp_for_each_cpu(cpu) {
-		struct perf_event **event = per_cpu_ptr (pe->pd, cpu);
+		perfcpu *pd = per_cpu_ptr (pe->pd, cpu);
+		struct perf_event **event = &(pd->event);
 		*event = perf_event_create_kernel_counter(attr, cpu, -1,
 							  callback);
 
@@ -53,12 +55,15 @@ static Perf _stp_perf_init (struct perf_event_attr *attr,
 			*event = NULL;
 			goto exit2;
 		}
+		pd->pp = pp;
+		pd->ph = ph;
 	}
 	return pe;
 
 exit2:
 	stp_for_each_cpu(cpu) {
-		struct perf_event **event = per_cpu_ptr (pe->pd, cpu);
+		perfcpu *pd = per_cpu_ptr (pe->pd, cpu);
+		struct perf_event **event = &(pd->event);
 		if (*event) perf_event_release_kernel(*event);
 	}
 	_stp_free_percpu(pe->pd);
@@ -72,13 +77,14 @@ exit1:
  *
  * @param pe
  */
-static void _stp_perf_del (Perf pe)
+static void _stp_perf_del (Perf *pe)
 {
 	if (pe) {
 		int cpu;
 		/* shut down performance event sampling */
 		stp_for_each_cpu(cpu) {
-			struct perf_event **event = per_cpu_ptr (pe->pd, cpu);
+			perfcpu *pd = per_cpu_ptr (pe->pd, cpu);
+			struct perf_event **event = &(pd->event);
 			if (*event) {
 				perf_event_release_kernel(*event);
 			}
diff --git a/runtime/perf.h b/runtime/perf.h
index 32383665..19f89fe7 100644
--- a/runtime/perf.h
+++ b/runtime/perf.h
@@ -16,17 +16,22 @@
  * @brief Header file for performance monitoring hardware support
  */
 
-struct _Perf {
-	/* per-cpu data. allocated with _stp_alloc_percpu() */
-	struct perf_event **pd;
-        perf_overflow_handler_t callback;
-};
+typedef struct {
+	struct perf_event *event;
+	const char *pp;
+	void (*ph) (struct context *);
+} perfcpu;
 
-typedef struct _Perf *Perf;
+typedef struct {
+	/* per-cpu data. allocated with _stp_alloc_percpu() */
+	perfcpu *pd;
+} Perf;
 
-static Perf _stp_perf_init (struct perf_event_attr *attr,
-			    perf_overflow_handler_t callback);
+static Perf *_stp_perf_init (struct perf_event_attr *attr,
+			     perf_overflow_handler_t callback,
+			     const char *pp,
+			     void (*ph) (struct context *) );
 
-static void _stp_perf_del (Perf pe);
+static void _stp_perf_del (Perf *pe);
 
 #endif /* _PERF_H_ */