[UMA] Use proper C++ objects to serialize tracked_objects across process boundaries.

content/common/child_process_messages.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Common IPC messages used for child processes.
 // Multiply-included message file, hence no include guard.
 
 #include "base/shared_memory.h"
 #include "base/tracked_objects.h"
 #include "base/values.h"
 #include "content/common/content_export.h"
+#include "content/public/common/process_type.h"
 #include "googleurl/src/gurl.h"
 #include "ipc/ipc_message_macros.h"
 
+IPC_ENUM_TRAITS(content::ProcessType)
 IPC_ENUM_TRAITS(tracked_objects::ThreadData::Status)
 
+IPC_STRUCT_TRAITS_BEGIN(tracked_objects::SerializedLocation)
+  IPC_STRUCT_TRAITS_MEMBER(file_name)
+  IPC_STRUCT_TRAITS_MEMBER(function_name)
+  IPC_STRUCT_TRAITS_MEMBER(line_number)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(tracked_objects::SerializedBirthOnThread)
+  IPC_STRUCT_TRAITS_MEMBER(location)
+  IPC_STRUCT_TRAITS_MEMBER(thread_name)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(tracked_objects::SerializedDeathData)
+  IPC_STRUCT_TRAITS_MEMBER(count)
+  IPC_STRUCT_TRAITS_MEMBER(run_duration_sum)
+  IPC_STRUCT_TRAITS_MEMBER(run_duration_max)
+  IPC_STRUCT_TRAITS_MEMBER(run_duration_sample)
+  IPC_STRUCT_TRAITS_MEMBER(queue_duration_sum)
+  IPC_STRUCT_TRAITS_MEMBER(queue_duration_max)
+  IPC_STRUCT_TRAITS_MEMBER(queue_duration_sample)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(tracked_objects::SerializedSnapshot)
+  IPC_STRUCT_TRAITS_MEMBER(birth)
+  IPC_STRUCT_TRAITS_MEMBER(death_data)
+  IPC_STRUCT_TRAITS_MEMBER(death_thread_name)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(tracked_objects::SerializedParentChildPair)
+  IPC_STRUCT_TRAITS_MEMBER(parent)
+  IPC_STRUCT_TRAITS_MEMBER(child)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(tracked_objects::SerializedProcessData)
+  IPC_STRUCT_TRAITS_MEMBER(snapshots)
+  IPC_STRUCT_TRAITS_MEMBER(descendants)
+  IPC_STRUCT_TRAITS_MEMBER(process_id)
+IPC_STRUCT_TRAITS_END()
+
 #undef IPC_MESSAGE_EXPORT
 #define IPC_MESSAGE_EXPORT CONTENT_EXPORT
 
 #define IPC_MESSAGE_START ChildProcessMsgStart
 
 // Messages sent from the browser to the child process.
 
 // Sent in response to ChildProcessHostMsg_ShutdownRequest to tell the child
 // process that it's safe to shutdown.
 IPC_MESSAGE_CONTROL0(ChildProcessMsg_Shutdown)
@@ skipping 15 matching lines @@
 // Sent to all child processes to get trace buffer fullness.
 IPC_MESSAGE_CONTROL0(ChildProcessMsg_GetTraceBufferPercentFull)
 
 // Tell the child process to enable or disable the profiler status.
 IPC_MESSAGE_CONTROL1(ChildProcessMsg_SetProfilerStatus,
                      tracked_objects::ThreadData::Status /* profiler status */)
 
 // Send to all the child processes to send back profiler data (ThreadData in
 // tracked_objects).
 IPC_MESSAGE_CONTROL2(ChildProcessMsg_GetChildProfilerData,
-                     int,         /* sequence number. */
-                     std::string  /* pickled Value of process type. */)
+                     int,                  /* sequence number */

[jam, 2012/03/18 19:31:54]

there's no need to tell the child process what type it is, just to have it send
it back. this information is usually just kept in the browser process. when you
create the filter for these messages in the browser, pass in the process type
there and hold it as a member

[Ilya Sherman, 2012/03/19 22:01:24]

Done.

+                     content::ProcessType  /* child process type */)
 
 // Sent to child processes to dump their handle table.
 IPC_MESSAGE_CONTROL0(ChildProcessMsg_DumpHandles)
 
 ////////////////////////////////////////////////////////////////////////////////
 // Messages sent from the child process to the browser.
 
 IPC_MESSAGE_CONTROL0(ChildProcessHostMsg_ShutdownRequest)
 
 // Notify the browser that this child process supports tracing.
 IPC_MESSAGE_CONTROL0(ChildProcessHostMsg_ChildSupportsTracing)
 
 // Reply from child processes acking ChildProcessMsg_TraceChangeStatus(false).
 IPC_MESSAGE_CONTROL1(ChildProcessHostMsg_EndTracingAck,
                      std::vector<std::string> /* known_categories */)
 
 // Sent if the trace buffer becomes full.
 IPC_MESSAGE_CONTROL0(ChildProcessHostMsg_TraceBufferFull)
 
 // Child processes send trace data back in JSON chunks.
 IPC_MESSAGE_CONTROL1(ChildProcessHostMsg_TraceDataCollected,
                      std::string /*json trace data*/)
 
 // Reply to ChildProcessMsg_GetTraceBufferPercentFull.
 IPC_MESSAGE_CONTROL1(ChildProcessHostMsg_TraceBufferPercentFullReply,
                      float /*trace buffer percent full*/)
 
 // Send back profiler data (ThreadData in tracked_objects).
-IPC_MESSAGE_CONTROL2(ChildProcessHostMsg_ChildProfilerData,
-                     int, /* sequence number. */
-                     DictionaryValue /* profiler data. */)
+IPC_MESSAGE_CONTROL3(ChildProcessHostMsg_ChildProfilerData,
+                     int,                  /* sequence number */
+                     tracked_objects::SerializedProcessData, /* profiler data */
+                     content::ProcessType  /* child process type */)
 
 // Reply to ChildProcessMsg_DumpHandles when handle table dump is complete.
 IPC_MESSAGE_CONTROL0(ChildProcessHostMsg_DumpHandlesDone)
 
 #if defined(OS_WIN)
 // Request that the given font be loaded by the host so it's cached by the
 // OS. Please see ChildProcessHost::PreCacheFont for details.
 IPC_SYNC_MESSAGE_CONTROL1_0(ChildProcessHostMsg_PreCacheFont,
                             LOGFONT /* font data */)
 
 // Release the cached font
 IPC_MESSAGE_CONTROL0(ChildProcessHostMsg_ReleaseCachedFonts)
 #endif  // defined(OS_WIN)
 
 // Asks the browser to create a block of shared memory for the child process to
 // fill in and pass back to the browser.
 IPC_SYNC_MESSAGE_CONTROL1_1(ChildProcessHostMsg_SyncAllocateSharedMemory,
                             uint32 /* buffer size */,
                             base::SharedMemoryHandle)