[Tracing] V8 Tracing Controller

src/d8.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 // Defined when linking against shared lib on Windows.
 #if defined(USING_V8_SHARED) && !defined(V8_SHARED)
 #define V8_SHARED
 #endif
 
@@ skipping 17 matching lines @@
 #endif  // V8_SHARED
 
 #ifdef ENABLE_VTUNE_JIT_INTERFACE
 #include "src/third_party/vtune/v8-vtune.h"
 #endif
 
 #include "src/d8.h"
 #include "src/ostreams.h"
 
 #include "include/libplatform/libplatform.h"
+#include "include/libplatform/v8-tracing.h"
 #ifndef V8_SHARED
 #include "src/api.h"
 #include "src/base/cpu.h"
 #include "src/base/logging.h"
 #include "src/base/platform/platform.h"
 #include "src/base/sys-info.h"
 #include "src/basic-block-profiler.h"
 #include "src/interpreter/interpreter.h"
 #include "src/snapshot/natives.h"
 #include "src/utils.h"
@@ skipping 1941 matching lines @@
         options.compile_options = v8::ScriptCompiler::kProduceCodeCache;
       } else if (strncmp(value, "=parse", 7) == 0) {
         options.compile_options = v8::ScriptCompiler::kProduceParserCache;
       } else if (strncmp(value, "=none", 6) == 0) {
         options.compile_options = v8::ScriptCompiler::kNoCompileOptions;
       } else {
         printf("Unknown option to --cache.\n");
         return false;
       }
       argv[i] = NULL;
+    } else if (strcmp(argv[i], "--enable-tracing") == 0) {
+      options.trace_enabled = true;
+      argv[i] = NULL;
+    } else if (strncmp(argv[i], "--trace-config=", 15) == 0) {
+      options.trace_config = argv[i] + 15;
+      argv[i] = NULL;
     }
   }
 
   v8::V8::SetFlagsFromCommandLine(&argc, argv, true);
 
   // Set up isolated source groups.
   options.isolate_sources = new SourceGroup[options.num_isolates];
   SourceGroup* current = options.isolate_sources;
   current->Begin(argv, 1);
   for (int i = 1; i < argc; i++) {
@@ skipping 396 matching lines @@
       printf("  (\"%s\", 0x%05" V8PRIxPTR "): \"%s\",\n", sname, p, n);
     }
   }
   printf("}\n");
 #undef ROOT_LIST_CASE
 }
 #endif  // !V8_SHARED
 
 
 int Shell::Main(int argc, char* argv[]) {
+  std::ofstream trace_file;
 #if (defined(_WIN32) || defined(_WIN64))
   UINT new_flags =
       SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX | SEM_NOOPENFILEERRORBOX;
   UINT existing_flags = SetErrorMode(new_flags);
   SetErrorMode(existing_flags | new_flags);
 #if defined(_MSC_VER)
   _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_DEBUG | _CRTDBG_MODE_FILE);
   _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);
   _CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_DEBUG | _CRTDBG_MODE_FILE);
   _CrtSetReportFile(_CRT_ASSERT, _CRTDBG_FILE_STDERR);
@@ skipping 47 matching lines @@
     create_params.create_histogram_callback = CreateHistogram;
     create_params.add_histogram_sample_callback = AddHistogramSample;
   }
 #endif
   Isolate* isolate = Isolate::New(create_params);
   {
     Isolate::Scope scope(isolate);
     Initialize(isolate);
     PerIsolateData data(isolate);
 
+    if (options.trace_enabled) {

[Yang, 2016/07/21 11:26:55]

Can we factor out all of this into a new function? Possibly integrate Jochen's
suggestion of doing JSON.parse from there rather than inside
CreateTraceConfigFromJSON.

[fmeawad, 2016/07/26 09:08:09]

It is now much simpler as we removed the trace_config check.

+      trace_file.open("v8_trace.json");
+      platform::tracing::TracingController* tracing_controller =
+          new platform::tracing::TracingController();
+      platform::tracing::TraceBuffer* trace_buffer =
+          platform::tracing::TraceBuffer::CreateTraceBufferRingBuffer(
+              platform::tracing::TraceBuffer::kRingBufferChunks,
+              platform::tracing::TraceWriter::CreateJSONTraceWriter(
+                  trace_file));
+      platform::tracing::TraceConfig* trace_config;
+      if (options.trace_config) {
+        int size = 0;
+        char* trace_config_str =

[Yang, 2016/07/21 11:26:55]

Is this string going to be deleted anywhere? It looks like it would leak.

[fmeawad, 2016/07/26 09:08:09]

Removed with the removal of the JSON config for now.

+            ReadChars(nullptr, options.trace_config, &size);
+        trace_config =
+            platform::tracing::TraceConfig::CreateTraceConfigFromJSON(
+                isolate, trace_config_str);
+      } else {
+        trace_config =
+            platform::tracing::TraceConfig::CreateDefaultTraceConfig();
+      }
+      tracing_controller->Initialize(trace_buffer);
+      tracing_controller->StartTracing(trace_config);
+#ifndef V8_SHARED
+      if (!i::FLAG_verify_predictable) {
+        platform::SetTracingController(g_platform, tracing_controller);
+      }
+#else
+      platform::SetTracingController(g_platform, tracing_controller);
+#endif
+    }
+
 #ifndef V8_SHARED
     if (options.dump_heap_constants) {
       DumpHeapConstants(reinterpret_cast<i::Isolate*>(isolate));
       return 0;
     }
 #endif
 
     if (options.stress_opt || options.stress_deopt) {
       Testing::SetStressRunType(options.stress_opt
                                 ? Testing::kStressTypeOpt
@@ skipping 61 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif