commit 469a194051f1657b3f77ff2f5d84a60f7521faba
author John Reck <jreck@google.com> Thu Mar 26 15:31:35 2015 -0700
committer John Reck <jreck@google.com> Thu Mar 26 16:57:30 2015 -0700
tree 7f51339c3009376c272f91bacd408ef574d44e00
parent bc5aceb1f0a68e96dced1d843278b3bf14504f2c

Add trace_event_clock_sync to atrace

Change-Id: I8adce15210d82df09ff3a39ddd8df617aeb16a42

cmds/atrace/atrace.cpp

diff --git a/cmds/atrace/atrace.cpp b/cmds/atrace/atrace.cpp
index 8fd80cc..515d761 100644
--- a/cmds/atrace/atrace.cpp
+++ b/cmds/atrace/atrace.cpp
@@ -35,6 +35,7 @@
 #include <cutils/properties.h>
 
 #include <utils/String8.h>
+#include <utils/Timers.h>
 #include <utils/Trace.h>
 
 using namespace android;
@@ -192,6 +193,9 @@
 static const char* k_tracePath =
     "/sys/kernel/debug/tracing/trace";
 
+static const char* k_traceMarkerPath =
+    "/sys/kernel/debug/tracing/trace_marker";
+
 // Check whether a file exists.
 static bool fileExists(const char* filename) {
     return access(filename, F_OK) != -1;
@@ -254,6 +258,14 @@
     return _writeStr(filename, str, O_APPEND|O_WRONLY);
 }
 
+static void writeClockSyncMarker()
+{
+  char buffer[128];
+  float now_in_seconds = systemTime(CLOCK_MONOTONIC) / 1000000000.0f;
+  snprintf(buffer, 128, "trace_event_clock_sync: parent_ts=%f\n", now_in_seconds);
+  writeStr(k_traceMarkerPath, buffer);
+}
+
 // Enable or disable a kernel option by writing a "1" or a "0" into a /sys
 // file.
 static bool setKernelOptionEnable(const char* filename, bool enable)
@@ -631,6 +643,7 @@
 // Disable tracing in the kernel.
 static void stopTrace()
 {
+    writeClockSyncMarker();
     setTracingEnabled(false);
 }