Remove Blink's ConvertableToTraceFormat

third_party/WebKit/Source/platform/EventTracer.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "platform/EventTracer.h"
 
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
+#include "base/trace_event/trace_event_argument.h"
+#include "platform/TracedValue.h"
 #include "public/platform/Platform.h"
 #include "wtf/Assertions.h"
 #include "wtf/text/StringUTF8Adaptor.h"
 #include <stdio.h>
 
 namespace blink {
 
 static_assert(sizeof(TraceEvent::TraceEventHandle) == sizeof(base::trace_event::TraceEventHandle), "TraceEventHandle types must be the same");
 static_assert(sizeof(TraceEvent::TraceEventAPIAtomicWord) == sizeof(const char*), "TraceEventAPIAtomicWord must be pointer-sized.");
 
-namespace {
-
-class ConvertableToTraceFormatWrapper : public base::trace_event::ConvertableToTraceFormat {
-public:
-    // We move a reference pointer from |convertable| to |m_convertable|,
-    // rather than copying, for thread safety. https://crbug.com/478149
-    explicit ConvertableToTraceFormatWrapper(PassRefPtr<blink::TraceEvent::ConvertableToTraceFormat> convertable)
-        : m_convertable(convertable)
-    {
-        ASSERT(m_convertable);
-    }
-    void AppendAsTraceFormat(std::string* out) const override
-    {
-        // TODO(bashi): Avoid copying.
-        String traceFormat = m_convertable->asTraceFormat();
-        StringUTF8Adaptor utf8(traceFormat);
-        out->append(utf8.data(), utf8.length());
-    }
-    void EstimateTraceMemoryOverhead(base::trace_event::TraceEventMemoryOverhead* overhead)
-    {
-        m_convertable->estimateTraceMemoryOverhead(overhead);
-    }
-
-private:
-    ~ConvertableToTraceFormatWrapper() override {}
-
-    RefPtr<blink::TraceEvent::ConvertableToTraceFormat> m_convertable;
-};
-
-} // namespace
-
 // The dummy variable is needed to avoid a crash when someone updates the state variables
 // before EventTracer::initialize() is called.
 TraceEvent::TraceEventAPIAtomicWord dummyTraceSamplingState = 0;
 TraceEvent::TraceEventAPIAtomicWord* traceSamplingState[3] = {&dummyTraceSamplingState, &dummyTraceSamplingState, &dummyTraceSamplingState };
 
 void EventTracer::initialize()
 {
     traceSamplingState[0] = reinterpret_cast<TraceEvent::TraceEventAPIAtomicWord*>(&TRACE_EVENT_API_THREAD_BUCKET(0));
     // FIXME: traceSamplingState[0] can be 0 in split-dll build. http://crbug.com/256965
     if (!traceSamplingState[0])
         traceSamplingState[0] = &dummyTraceSamplingState;
     traceSamplingState[1] = reinterpret_cast<TraceEvent::TraceEventAPIAtomicWord*>(&TRACE_EVENT_API_THREAD_BUCKET(1));
     if (!traceSamplingState[1])
         traceSamplingState[1] = &dummyTraceSamplingState;
     traceSamplingState[2] = reinterpret_cast<TraceEvent::TraceEventAPIAtomicWord*>(&TRACE_EVENT_API_THREAD_BUCKET(2));
     if (!traceSamplingState[2])
         traceSamplingState[2] = &dummyTraceSamplingState;
 }
 
 const unsigned char* EventTracer::getTraceCategoryEnabledFlag(const char* categoryName)
 {
     return TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(categoryName);
 }
 
 TraceEvent::TraceEventHandle EventTracer::addTraceEvent(char phase, const unsigned char* categoryEnabledFlag,
     const char* name, unsigned long long id, unsigned long long bindId, double timestamp,
     int numArgs, const char* argNames[], const unsigned char argTypes[],
     const unsigned long long argValues[],
-    PassRefPtr<TraceEvent::ConvertableToTraceFormat> convertableValue1,
-    PassRefPtr<TraceEvent::ConvertableToTraceFormat> convertableValue2,
+    PassRefPtr<TracedValue> convertableValue1,
+    PassRefPtr<TracedValue> convertableValue2,
     unsigned flags)
 {
-    scoped_refptr<base::trace_event::ConvertableToTraceFormat> wrappers[2];
+    scoped_refptr<base::trace_event::ConvertableToTraceFormat> convertables[2];
     ASSERT(numArgs <= 2);
     if (numArgs >= 1 && argTypes[0] == TRACE_VALUE_TYPE_CONVERTABLE)
-        wrappers[0] = new ConvertableToTraceFormatWrapper(convertableValue1);
+        convertables[0] = convertableValue1->m_tracedValue;

[hiroshige, 2016/01/28 12:05:01]

Probably we have to move the scoped_ptr from |convertableValue1->m_tracedValue|
to |convertables[0]|, so that |convertableValue1->m_tracedValue| becomes null
after this line for thread safety,
as ConvertableToTraceFormatWrapper() did similar things.
(See comments in L49-50 in ConvertableToTraceFormatWrapper)

[bashi, 2016/01/29 02:25:26]

Good catch! Done.

     if (numArgs >= 2 && argTypes[1] == TRACE_VALUE_TYPE_CONVERTABLE)
-        wrappers[1] = new ConvertableToTraceFormatWrapper(convertableValue2);
-    return addTraceEvent(phase, categoryEnabledFlag, name, id, bindId, timestamp, numArgs, argNames, argTypes, argValues, wrappers, flags);
+        convertables[1] = convertableValue2->m_tracedValue;

[hiroshige, 2016/01/28 12:05:01]

ditto.

+    return addTraceEvent(phase, categoryEnabledFlag, name, id, bindId, timestamp, numArgs, argNames, argTypes, argValues, convertables, flags);
 }
 
 TraceEvent::TraceEventHandle EventTracer::addTraceEvent(char phase, const unsigned char* categoryEnabledFlag,
     const char* name, unsigned long long id, unsigned long long bindId, double timestamp,
     int numArgs, const char** argNames, const unsigned char* argTypes,
     const unsigned long long* argValues, unsigned flags)
 {
     return addTraceEvent(phase, categoryEnabledFlag, name, id, bindId, timestamp, numArgs, argNames, argTypes, argValues, nullptr, flags);
 }
 
@@ skipping 15 matching lines @@
     memcpy(&traceEventHandle, &handle, sizeof(handle));
     TRACE_EVENT_API_UPDATE_TRACE_EVENT_DURATION(categoryEnabledFlag, name, traceEventHandle);
 }
 
 double EventTracer::systemTraceTime()
 {
     return (base::TimeTicks::Now() - base::TimeTicks()).InSecondsF();
 }
 
 } // namespace blink