rts: Tracing support for nonmoving collection events

This introduces a few events to mark key points in the nonmoving
garbage collection cycle. These include:

 * `EVENT_CONC_MARK_BEGIN`, denoting the beginning of a round of
   marking. This may happen more than once in a single major collection
   since we the major collector iterates until it hits a fixed point.

 * `EVENT_CONC_MARK_END`, denoting the end of a round of marking.

 * `EVENT_CONC_SYNC_BEGIN`, denoting the beginning of the post-mark
   synchronization phase

 * `EVENT_CONC_UPD_REM_SET_FLUSH`, indicating that a capability has
   flushed its update remembered set.

 * `EVENT_CONC_SYNC_END`, denoting that all mutators have flushed their
   update remembered sets.

 * `EVENT_CONC_SWEEP_BEGIN`, denoting the beginning of the sweep portion
   of the major collection.

 * `EVENT_CONC_SWEEP_END`, denoting the end of the sweep portion of the
   major collection.

1 files changed, 16 insertions, 0 deletions

diff --git a/rts/Trace.h b/rts/Trace.h
index be4d844a6b..9b52c3cb65 100644
--- a/rts/Trace.h
+++ b/rts/Trace.h
@@ -304,6 +304,14 @@ void traceHeapProfSampleCostCentre(StgWord8 profile_id,
                                    CostCentreStack *stack, StgWord residency);
 #endif /* PROFILING */
 
+void traceConcMarkBegin(void);
+void traceConcMarkEnd(StgWord32 marked_obj_count);
+void traceConcSyncBegin(void);
+void traceConcSyncEnd(void);
+void traceConcSweepBegin(void);
+void traceConcSweepEnd(void);
+void traceConcUpdRemSetFlush(Capability *cap);
+
 void flushTrace(void);
 
 #else /* !TRACING */
@@ -344,6 +352,14 @@ void flushTrace(void);
 #define traceHeapProfSampleCostCentre(profile_id, stack, residency) /* nothing */
 #define traceHeapProfSampleString(profile_id, label, residency) /* nothing */
 
+#define traceConcMarkBegin() /* nothing */
+#define traceConcMarkEnd(marked_obj_count) /* nothing */
+#define traceConcSyncBegin() /* nothing */
+#define traceConcSyncEnd() /* nothing */
+#define traceConcSweepBegin() /* nothing */
+#define traceConcSweepEnd() /* nothing */
+#define traceConcUpdRemSetFlush(cap) /* nothing */
+
 #define flushTrace() /* nothing */
 
 #endif /* TRACING */