v7.x: cherry-pick tracing related fixes

node.gyp

@@ -234,6 +234,9 @@
         'src/stream_base.h',
         'src/stream_base-inl.h',
         'src/stream_wrap.h',
+        'src/tracing/agent.h',
+        'src/tracing/node_trace_buffer.h',
+        'src/tracing/node_trace_writer.h',
         'src/tracing/trace_event.h'
         'src/tree.h',
         'src/util.h',

src/node.h

@@ -41,7 +41,6 @@
 
 #include "v8.h"  // NOLINT(build/include_order)
 #include "node_version.h"  // NODE_MODULE_VERSION
-#include "tracing/trace_event.h"
 
 #define NODE_MAKE_VERSION(major, minor, patch)                                \
   ((major) * 0x1000 + (minor) * 0x100 + (patch))

src/node_internals.h

@@ -8,6 +8,7 @@
 #include "util-inl.h"
 #include "uv.h"
 #include "v8.h"
+#include "tracing/trace_event.h"
 
 #include <stdint.h>
 #include <stdlib.h>

src/tracing/agent.cc

@@ -56,7 +56,9 @@ void Agent::Stop() {
   // Perform final Flush on TraceBuffer. We don't want the tracing controller
   // to flush the buffer again on destruction of the V8::Platform.
   tracing_controller_->StopTracing();
-  delete tracing_controller_;
+  tracing_controller_->Initialize(nullptr);
+  tracing_controller_ = nullptr;
+
   // Thread should finish when the tracing loop is stopped.
   uv_thread_join(&thread_);
   v8::platform::SetTracingController(platform_, nullptr);

src/tracing/agent.h

@@ -22,7 +22,7 @@ class Agent {
   uv_thread_t thread_;
   uv_loop_t tracing_loop_;
   v8::Platform* platform_ = nullptr;
-  TracingController* tracing_controller_;
+  TracingController* tracing_controller_ = nullptr;
 };
 
 }  // namespace tracing

src/tracing/node_trace_buffer.cc

@@ -4,9 +4,9 @@ namespace node {
 namespace tracing {
 
 InternalTraceBuffer::InternalTraceBuffer(size_t max_chunks, uint32_t id,
-    NodeTraceWriter* trace_writer, NodeTraceBuffer* external_buffer)
-    : id_(id), flushing_(false), max_chunks_(max_chunks),
-      trace_writer_(trace_writer), external_buffer_(external_buffer) {
+                                         NodeTraceWriter* trace_writer)
+    : flushing_(false), max_chunks_(max_chunks),
+      trace_writer_(trace_writer), id_(id) {
   chunks_.resize(max_chunks);
 }
 
@@ -89,8 +89,8 @@ void InternalTraceBuffer::ExtractHandle(
 NodeTraceBuffer::NodeTraceBuffer(size_t max_chunks,
     NodeTraceWriter* trace_writer, uv_loop_t* tracing_loop)
     : tracing_loop_(tracing_loop), trace_writer_(trace_writer),
-      buffer1_(max_chunks, 0, trace_writer, this),
-      buffer2_(max_chunks, 1, trace_writer, this) {
+      buffer1_(max_chunks, 0, trace_writer),
+      buffer2_(max_chunks, 1, trace_writer) {
   current_buf_.store(&buffer1_);
 
   flush_signal_.data = this;

src/tracing/node_trace_buffer.h

@@ -20,8 +20,7 @@ class NodeTraceBuffer;
 class InternalTraceBuffer {
  public:
   InternalTraceBuffer(size_t max_chunks, uint32_t id,
-                      NodeTraceWriter* trace_writer,
-                      NodeTraceBuffer* external_buffer);
+                      NodeTraceWriter* trace_writer);
 
   TraceObject* AddTraceEvent(uint64_t* handle);
   TraceObject* GetEventByHandle(uint64_t handle);
@@ -44,7 +43,6 @@ class InternalTraceBuffer {
   bool flushing_;
   size_t max_chunks_;
   NodeTraceWriter* trace_writer_;
-  NodeTraceBuffer* external_buffer_;
   std::vector<std::unique_ptr<TraceBufferChunk>> chunks_;
   size_t total_chunks_ = 0;
   uint32_t current_chunk_seq_ = 1;

test/parallel/test-trace-event.js

@@ -21,15 +21,19 @@ proc_no_categories.once('exit', common.mustCall(() => {
 
   proc.once('exit', common.mustCall(() => {
     assert(common.fileExists(FILE_NAME));
-    fs.readFile(FILE_NAME, (err, data) => {
+    fs.readFile(FILE_NAME, common.mustCall((err, data) => {
       const traces = JSON.parse(data.toString()).traceEvents;
       assert(traces.length > 0);
       // Values that should be present on all runs to approximate correctness.
-      assert(traces.some((trace) => { return trace.pid === proc.pid; }));
-      assert(traces.some((trace) => { return trace.cat === 'v8'; }));
       assert(traces.some((trace) => {
-        return trace.name === 'V8.ScriptCompiler';
+        if (trace.pid !== proc.pid)
+          return false;
+        if (trace.cat !== 'v8')
+          return false;
+        if (trace.name !== 'V8.ScriptCompiler')
+          return false;
+        return true;
       }));
-    });
+    }));
   }));
 }));