1 // Copyright 2016 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/tracing/tracing-category-observer.h"
6 
7 #include "src/flags.h"
8 #include "src/tracing/trace-event.h"
9 #include "src/v8.h"
10 
11 namespace v8 {
12 namespace tracing {
13 
14 TracingCategoryObserver* TracingCategoryObserver::instance_ = nullptr;
15 
SetUp()16 void TracingCategoryObserver::SetUp() {
17   TracingCategoryObserver::instance_ = new TracingCategoryObserver();
18   v8::internal::V8::GetCurrentPlatform()->AddTraceStateObserver(
19       TracingCategoryObserver::instance_);
20   TRACE_EVENT_WARMUP_CATEGORY(TRACE_DISABLED_BY_DEFAULT("v8.runtime_stats"));
21   TRACE_EVENT_WARMUP_CATEGORY(
22       TRACE_DISABLED_BY_DEFAULT("v8.runtime_stats_sampling"));
23   TRACE_EVENT_WARMUP_CATEGORY(TRACE_DISABLED_BY_DEFAULT("v8.gc_stats"));
24 }
25 
TearDown()26 void TracingCategoryObserver::TearDown() {
27   v8::internal::V8::GetCurrentPlatform()->RemoveTraceStateObserver(
28       TracingCategoryObserver::instance_);
29   delete TracingCategoryObserver::instance_;
30 }
31 
OnTraceEnabled()32 void TracingCategoryObserver::OnTraceEnabled() {
33   bool enabled = false;
34   TRACE_EVENT_CATEGORY_GROUP_ENABLED(
35       TRACE_DISABLED_BY_DEFAULT("v8.runtime_stats"), &enabled);
36   if (enabled) {
37     v8::internal::FLAG_runtime_stats |= ENABLED_BY_TRACING;
38   }
39   TRACE_EVENT_CATEGORY_GROUP_ENABLED(
40       TRACE_DISABLED_BY_DEFAULT("v8.runtime_stats_sampling"), &enabled);
41   if (enabled) {
42     v8::internal::FLAG_runtime_stats |= ENABLED_BY_SAMPLING;
43   }
44   TRACE_EVENT_CATEGORY_GROUP_ENABLED(TRACE_DISABLED_BY_DEFAULT("v8.gc_stats"),
45                                      &enabled);
46   if (enabled) {
47     v8::internal::FLAG_gc_stats |= ENABLED_BY_TRACING;
48   }
49 }
50 
OnTraceDisabled()51 void TracingCategoryObserver::OnTraceDisabled() {
52   v8::internal::FLAG_runtime_stats &=
53       ~(ENABLED_BY_TRACING | ENABLED_BY_SAMPLING);
54   v8::internal::FLAG_gc_stats &= ~ENABLED_BY_TRACING;
55 }
56 
57 }  // namespace tracing
58 }  // namespace v8
59