From: Alex Rønne Petersen <alexrp@xamarin.com>
Date: Sun, 18 Jun 2017 03:41:28 +0000 (+0200)
Subject: [profiler] Simplify the encoding of monitor events.
X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=commitdiff_plain;h=1520a7aaba6b2bbb8e68b7cc576c4b9588bbfc0a;p=mono.git

[profiler] Simplify the encoding of monitor events.

The way the event was encoded was highly irregular with respect to the rest of
the format.
---

diff --git a/mono/profiler/log.c b/mono/profiler/log.c
index 817ea4d5235..7a04f7620a5 100644
--- a/mono/profiler/log.c
+++ b/mono/profiler/log.c
@@ -121,9 +121,7 @@ static gint32 sync_points_ctr,
               code_buffers_ctr,
               exception_throws_ctr,
               exception_clauses_ctr,
-              monitor_contentions_ctr,
-              monitor_acquisitions_ctr,
-              monitor_failures_ctr,
+              monitor_events_ctr,
               thread_starts_ctr,
               thread_ends_ctr,
               thread_names_ctr,
@@ -2113,33 +2111,17 @@ clause_exc (MonoProfiler *prof, MonoMethod *method, int clause_type, int clause_
 }
 
 static void
-monitor_event (MonoProfiler *profiler, MonoObject *object, MonoProfilerMonitorEvent event)
+monitor_event (MonoProfiler *profiler, MonoObject *object, MonoProfilerMonitorEvent ev)
 {
-	int do_bt = (nocalls && InterlockedRead (&runtime_inited) && !notraces && event == MONO_PROFILER_MONITOR_CONTENTION) ? TYPE_MONITOR_BT : 0;
+	int do_bt = (nocalls && InterlockedRead (&runtime_inited) && !notraces) ? TYPE_MONITOR_BT : 0;
 	FrameData data;
 
 	if (do_bt)
 		collect_bt (&data);
 
-	gint32 *ctr;
-
-	switch (event) {
-	case MONO_PROFILER_MONITOR_CONTENTION:
-		ctr = &monitor_contentions_ctr;
-		break;
-	case MONO_PROFILER_MONITOR_DONE:
-		ctr = &monitor_acquisitions_ctr;
-		break;
-	case MONO_PROFILER_MONITOR_FAIL:
-		ctr = &monitor_failures_ctr;
-		break;
-	default:
-		g_assert_not_reached ();
-		break;
-	}
-
-	ENTER_LOG (ctr, logbuffer,
+	ENTER_LOG (&monitor_events_ctr, logbuffer,
 		EVENT_SIZE /* event */ +
+		BYTE_SIZE /* ev */ +
 		LEB128_SIZE /* object */ +
 		(do_bt ? (
 			LEB128_SIZE /* count */ +
@@ -2149,7 +2131,8 @@ monitor_event (MonoProfiler *profiler, MonoObject *object, MonoProfilerMonitorEv
 		) : 0)
 	);
 
-	emit_event (logbuffer, (event << 4) | do_bt | TYPE_MONITOR);
+	emit_event (logbuffer, do_bt | TYPE_MONITOR);
+	emit_byte (logbuffer, ev);
 	emit_obj (logbuffer, object);
 
 	if (do_bt)
@@ -4468,9 +4451,7 @@ runtime_initialized (MonoProfiler *profiler)
 	register_counter ("Event: Code buffers", &code_buffers_ctr);
 	register_counter ("Event: Exception throws", &exception_throws_ctr);
 	register_counter ("Event: Exception clauses", &exception_clauses_ctr);
-	register_counter ("Event: Monitor contentions", &monitor_contentions_ctr);
-	register_counter ("Event: Monitor acquisitions", &monitor_acquisitions_ctr);
-	register_counter ("Event: Monitor failures", &monitor_failures_ctr);
+	register_counter ("Event: Monitor events", &monitor_events_ctr);
 	register_counter ("Event: Thread starts", &thread_starts_ctr);
 	register_counter ("Event: Thread ends", &thread_ends_ctr);
 	register_counter ("Event: Thread names", &thread_names_ctr);
diff --git a/mono/profiler/mprof-report.c b/mono/profiler/mprof-report.c
index 322eb623b34..eab9d32a00e 100644
--- a/mono/profiler/mprof-report.c
+++ b/mono/profiler/mprof-report.c
@@ -2736,9 +2736,13 @@ decode_buffer (ProfContext *ctx)
 			break;
 		}
 		case TYPE_MONITOR: {
-			int event = (*p >> 4) & 0x3;
 			int has_bt = *p & TYPE_MONITOR_BT;
+			int event;
+			if (ctx->data_version < 13)
+				event = (*p >> 4) & 0x3;
 			uint64_t tdiff = decode_uleb128 (p + 1, &p);
+			if (ctx->data_version > 13)
+				event = *p++;
 			intptr_t objdiff = decode_sleb128 (p, &p);
 			MethodDesc* sframes [8];
 			MethodDesc** frames = sframes;
@@ -2749,27 +2753,14 @@ decode_buffer (ProfContext *ctx)
 			record = (!thread_filter || thread_filter == thread->thread_id);
 			if (!(time_base >= time_from && time_base < time_to))
 				record = 0;
+			MonitorDesc *mdesc = lookup_monitor (OBJ_ADDR (objdiff));
 			if (event == MONO_PROFILER_MONITOR_CONTENTION) {
-				MonitorDesc *mdesc = lookup_monitor (OBJ_ADDR (objdiff));
 				if (record) {
 					monitor_contention++;
 					mdesc->contentions++;
 					thread->monitor = mdesc;
 					thread->contention_start = time_base;
 				}
-				if (has_bt) {
-					num_bt = 8;
-					frames = decode_bt (ctx, sframes, &num_bt, p, &p, ptr_base, &method_base);
-					if (!frames) {
-						fprintf (outfile, "Cannot load backtrace\n");
-						return 0;
-					}
-					if (record)
-						add_trace_methods (frames, num_bt, &mdesc->traces, 1);
-				} else {
-					if (record)
-						add_trace_thread (thread, &mdesc->traces, 1);
-				}
 			} else if (event == MONO_PROFILER_MONITOR_FAIL) {
 				if (record) {
 					monitor_failed++;
@@ -2795,6 +2786,19 @@ decode_buffer (ProfContext *ctx)
 					}
 				}
 			}
+			if (has_bt) {
+				num_bt = 8;
+				frames = decode_bt (ctx, sframes, &num_bt, p, &p, ptr_base, &method_base);
+				if (!frames) {
+					fprintf (outfile, "Cannot load backtrace\n");
+					return 0;
+				}
+				if (record && event == MONO_PROFILER_MONITOR_CONTENTION)
+					add_trace_methods (frames, num_bt, &mdesc->traces, 1);
+			} else {
+				if (record)
+					add_trace_thread (thread, &mdesc->traces, 1);
+			}
 			if (debug)
 				fprintf (outfile, "monitor %s for object %p\n", monitor_ev_name (event), (void*)OBJ_ADDR (objdiff));
 			if (frames != sframes)