Add option to export tracing events to ETW.

- Exporting of ETW events can be turned on using --trace-export-events-to-etw.

BUG=

Review URL: https://codereview.chromium.org/1038453002

Cr-Commit-Position: refs/heads/master@{#324982}

4 files changed, 13 insertions, 0 deletions

diff --git a/content/app/content_main_runner.cc b/content/app/content_main_runner.cc
index 42f1865..0db941a 100644
--- a/content/app/content_main_runner.cc
+++ b/content/app/content_main_runner.cc
@@ -77,6 +77,7 @@
 #include <cstring>
 
 #include "base/strings/string_number_conversions.h"
+#include "base/trace_event/trace_event_etw_export_win.h"
 #include "ui/base/win/atl_module.h"
 #include "ui/gfx/win/dpi.h"
 #elif defined(OS_MACOSX)
@@ -632,6 +633,12 @@ class ContentMainRunnerImpl : public ContentMainRunner {
           base::trace_event::TraceOptions(
               base::trace_event::RECORD_UNTIL_FULL));
     }
+#if defined(OS_WIN)
+    // Enable exporting of events to ETW if requested on the command line.
+    if (command_line.HasSwitch(switches::kTraceExportEventsToETW))
+      base::trace_event::TraceEventETWExport::EnableETWExport();
+#endif  // OS_WIN
+
 #if !defined(OS_ANDROID)
     // Android tracing started at the beginning of the method.
     // Other OSes have to wait till we get here in order for all the memory
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 2f48c18..ba00a69 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -1381,6 +1381,7 @@ void RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer(
     switches::kDisableDirectWrite,
     switches::kEnableWin32kRendererLockDown,
     switches::kDisableWin32kRendererLockDown,
+    switches::kTraceExportEventsToETW,
 #endif
 #if defined(OS_CHROMEOS)
     switches::kDisableVaapiAcceleratedVideoEncode,
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index 17e95ef..d4fd005 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -987,6 +987,10 @@ const char kEnableWin32kRendererLockDown[] =
 // This switch allows specifying suffix to shared memory section name to avoid
 // clashes between different instances of Chrome.
 const char kFontCacheSharedMemSuffix[] = "font-cache-shared-mem-suffix";
+
+// Enables the exporting of the tracing events to ETW. This is only supported on
+// Windows Vista and later.
+const char kTraceExportEventsToETW[] = "trace-export-events-to-etw";
 #endif
 
 // Enables the use of NPAPI plugins.
diff --git a/content/public/common/content_switches.h b/content/public/common/content_switches.h
index a8c8608..00dd881 100644
--- a/content/public/common/content_switches.h
+++ b/content/public/common/content_switches.h
@@ -297,6 +297,7 @@ CONTENT_EXPORT extern const char kEnableWin32kRendererLockDown[];
 // Switch to uniquely identify names shared memory section for font cache
 // across chromium flavors.
 CONTENT_EXPORT extern const char kFontCacheSharedMemSuffix[];
+CONTENT_EXPORT extern const char kTraceExportEventsToETW[];
 #endif
 
 CONTENT_EXPORT extern const char kEnableNpapi[];