From dda8a837ce51fa7fe020bfb3f017fbcdb138f875 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Peter=20Bostr=C3=B6m?= <pbos@webrtc.org>
Date: Mon, 29 Feb 2016 14:54:04 +0100
Subject: [PATCH] Trace tracing Start/Stop events.

Permits measuring times from start of recording (usually start of a
call), and not time from first event that occurs after tracing starts.

BUG=
R=tommi@webrtc.org

Review URL: https://codereview.webrtc.org/1746693002 .

Cr-Commit-Position: refs/heads/master@{#11815}
---
 webrtc/base/event_tracer.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/webrtc/base/event_tracer.cc b/webrtc/base/event_tracer.cc
index 4174589d36..9e777a85ce 100644
--- a/webrtc/base/event_tracer.cc
+++ b/webrtc/base/event_tracer.cc
@@ -139,6 +139,7 @@ class EventLogger final {
   }
 
   void Start(FILE* file, bool owned) {
+    RTC_DCHECK(thread_checker_.CalledOnValidThread());
     RTC_DCHECK(file);
     RTC_DCHECK(!output_file_);
     output_file_ = file;
@@ -158,9 +159,12 @@ class EventLogger final {
 
     // Finally start, everything should be set up now.
     logging_thread_.Start();
+    TRACE_EVENT_INSTANT0("webrtc", "EventLogger::Start");
   }
 
   void Stop() {
+    RTC_DCHECK(thread_checker_.CalledOnValidThread());
+    TRACE_EVENT_INSTANT0("webrtc", "EventLogger::Stop");
     // Try to stop. Abort if we're not currently logging.
     if (rtc::AtomicOps::CompareAndSwap(&g_event_logging_active, 1, 0) == 0)
       return;