Bug 736643 - Add timestamp support to GC/CC JSON output (r=terrence)

dom/base/nsJSEnvironment.cpp

@@ -3163,7 +3163,8 @@ nsJSContext::CycleCollectNow(nsICycleCollectorListener *aListener,
     }
 
     NS_NAMED_MULTILINE_LITERAL_STRING(kJSONFmt,
-      NS_LL("{ \"duration\": %llu, ")
+       NS_LL("{ \"timestamp\": %llu, ")
+         NS_LL("\"duration\": %llu, ")
          NS_LL("\"suspected\": %lu, ")
          NS_LL("\"visited\": { ")
              NS_LL("\"RCed\": %lu, ")
@@ -3183,18 +3184,18 @@ nsJSContext::CycleCollectNow(nsICycleCollectorListener *aListener,
        NS_LL("}"));
     nsString json;
     json.Adopt(nsTextFormatter::smprintf(kJSONFmt.get(),
-                                        (now - start) / PR_USEC_PER_MSEC, suspected,
-                                        ccResults.mVisitedRefCounted, ccResults.mVisitedGCed,
-                                        ccResults.mFreedRefCounted, ccResults.mFreedGCed,
-                                        sCCollectedWaitingForGC,
-                                        ccResults.mForcedGC,
-                                        sForgetSkippableBeforeCC,
-                                        sMinForgetSkippableTime / PR_USEC_PER_MSEC,
-                                        sMaxForgetSkippableTime / PR_USEC_PER_MSEC,
-                                        (sTotalForgetSkippableTime / cleanups) /
-                                          PR_USEC_PER_MSEC,
-                                        sTotalForgetSkippableTime / PR_USEC_PER_MSEC,
-                                        sRemovedPurples));
+                                         now, (now - start) / PR_USEC_PER_MSEC, suspected,
+                                         ccResults.mVisitedRefCounted, ccResults.mVisitedGCed,
+                                         ccResults.mFreedRefCounted, ccResults.mFreedGCed,
+                                         sCCollectedWaitingForGC,
+                                         ccResults.mForcedGC,
+                                         sForgetSkippableBeforeCC,
+                                         sMinForgetSkippableTime / PR_USEC_PER_MSEC,
+                                         sMaxForgetSkippableTime / PR_USEC_PER_MSEC,
+                                         (sTotalForgetSkippableTime / cleanups) /
+                                           PR_USEC_PER_MSEC,
+                                         sTotalForgetSkippableTime / PR_USEC_PER_MSEC,
+                                         sRemovedPurples));
     nsCOMPtr<nsIObserverService> observerService = mozilla::services::GetObserverService();
     if (observerService) {
       observerService->NotifyObservers(nsnull, "cycle-collection-statistics", json.get());
@@ -3506,6 +3507,11 @@ DOMGCSliceCallback(JSRuntime *aRt, js::GCProgress aProgress, const js::GCDescrip
     if (cs) {
       cs->LogStringMessage(msg.get());
     }
+
+    nsString json;
+    json.Adopt(aDesc.formatJSON(aRt, now));
+    nsRefPtr<NotifyGCEndRunnable> notify = new NotifyGCEndRunnable(json);
+    NS_DispatchToMainThread(notify);
   }
 
   // Prevent cycle collections and shrinking during incremental GC.
@@ -3529,11 +3535,6 @@ DOMGCSliceCallback(JSRuntime *aRt, js::GCProgress aProgress, const js::GCDescrip
     sCCollectedWaitingForGC = 0;
     sCleanupSinceLastGC = false;
 
-    nsString json;
-    json.Adopt(aDesc.formatJSON(aRt));
-    nsRefPtr<NotifyGCEndRunnable> notify = new NotifyGCEndRunnable(json);
-    NS_DispatchToMainThread(notify);
-
     if (aDesc.isCompartment) {
       // If this is a compartment GC, restart it. We still want
       // a full GC to happen. Compartment GCs usually happen as a

js/src/gc/Statistics.cpp

@@ -310,7 +310,7 @@ formatPhases(StatisticsSerializer &ss, const char *name, int64_t *times)
 }
 
 bool
-Statistics::formatData(StatisticsSerializer &ss)
+Statistics::formatData(StatisticsSerializer &ss, uint64_t timestamp)
 {
     int64_t total = 0, longest = 0;
     for (SliceData *slice = slices.begin(); slice != slices.end(); slice++) {
@@ -323,6 +323,8 @@ Statistics::formatData(StatisticsSerializer &ss)
     double mmu50 = computeMMU(50 * PRMJ_USEC_PER_MSEC);
 
     ss.beginObject(NULL);
+    if (ss.isJSON())
+        ss.appendNumber("Timestamp", "%llu", "", (unsigned long long)timestamp);
     ss.appendNumber("Total Time", "%.1f", "ms", t(total));
     ss.appendString("Type", compartment ? "compartment" : "global");
     ss.appendNumber("MMU (20ms)", "%d", "%", int(mmu20 * 100));
@@ -377,15 +379,15 @@ jschar *
 Statistics::formatMessage()
 {
     StatisticsSerializer ss(StatisticsSerializer::AsText);
-    formatData(ss);
+    formatData(ss, 0);
     return ss.finishJSString();
 }
 
 jschar *
-Statistics::formatJSON()
+Statistics::formatJSON(uint64_t timestamp)
 {
     StatisticsSerializer ss(StatisticsSerializer::AsJSON);
-    formatData(ss);
+    formatData(ss, timestamp);
     return ss.finishJSString();
 }
 
@@ -449,7 +451,7 @@ Statistics::printStats()
 {
     if (fullFormat) {
         StatisticsSerializer ss(StatisticsSerializer::AsText);
-        formatData(ss);
+        formatData(ss, 0);
         char *msg = ss.finishCString();
         if (msg) {
             fprintf(fp, "GC(T+%.3fs) %s\n", t(slices[0].start - startupTime) / 1000.0, msg);

js/src/gc/Statistics.h

@@ -106,7 +106,7 @@ struct Statistics {
     }
 
     jschar *formatMessage();
-    jschar *formatJSON();
+    jschar *formatJSON(uint64_t timestamp);
 
   private:
     JSRuntime *runtime;
@@ -156,7 +156,7 @@ struct Statistics {
 
     int64_t gcDuration();
     void printStats();
-    bool formatData(StatisticsSerializer &ss);
+    bool formatData(StatisticsSerializer &ss, uint64_t timestamp);
 
     double computeMMU(int64_t resolution);
 };

js/src/jsfriendapi.cpp

@@ -724,9 +724,9 @@ GCDescription::formatMessage(JSRuntime *rt) const
 }
 
 jschar *
-GCDescription::formatJSON(JSRuntime *rt) const
+GCDescription::formatJSON(JSRuntime *rt, uint64_t timestamp) const
 {
-    return rt->gcStats.formatJSON();
+    return rt->gcStats.formatJSON(timestamp);
 }
 
 JS_FRIEND_API(bool)

js/src/jsfriendapi.h

@@ -706,7 +706,7 @@ struct JS_FRIEND_API(GCDescription) {
       : isCompartment(isCompartment) {}
 
     jschar *formatMessage(JSRuntime *rt) const;
-    jschar *formatJSON(JSRuntime *rt) const;
+    jschar *formatJSON(JSRuntime *rt, uint64_t timestamp) const;
 };
 
 typedef void