Bug 497808. Enable dumping of cycle-collector graphs in any debug build. r=peterv,a=blocking

dom/base/nsDOMWindowUtils.cpp

@@ -521,7 +521,7 @@ nsDOMWindowUtils::Focus(nsIDOMElement* aElement)
 }
 
 NS_IMETHODIMP
-nsDOMWindowUtils::GarbageCollect()
+nsDOMWindowUtils::GarbageCollect(PRBool aDrawGraph)
 {
   // Always permit this in debug builds.
 #ifndef DEBUG
@@ -530,7 +530,7 @@ nsDOMWindowUtils::GarbageCollect()
   }
 #endif
 
-  nsJSContext::CC();
+  nsJSContext::CC(aDrawGraph);
 
   return NS_OK;
 }

dom/base/nsJSEnvironment.cpp

@@ -307,7 +307,7 @@ NS_IMETHODIMP
 nsCCMemoryPressureObserver::Observe(nsISupports* aSubject, const char* aTopic,
                                     const PRUnichar* aData)
 {
-  nsJSContext::CC();
+  nsJSContext::CC(PR_FALSE);
   return NS_OK;
 }
 
@@ -973,7 +973,7 @@ nsJSContext::DOMOperationCallback(JSContext *cx)
   mem->IsLowMemory(&lowMemory);
   if (lowMemory) {
     // try to clean up:
-    nsJSContext::CC();
+    nsJSContext::CC(PR_FALSE);
 
     // never prevent system scripts from running
     if (!::JS_IsSystemObject(cx, ::JS_GetGlobalObject(cx))) {
@@ -3616,7 +3616,7 @@ nsJSContext::ScriptExecuted()
 
 //static
 void
-nsJSContext::CC()
+nsJSContext::CC(PRBool aDrawGraph)
 {
   NS_TIME_FUNCTION_MIN(1.0);
 
@@ -3631,7 +3631,7 @@ nsJSContext::CC()
   // nsCycleCollector_collect() no longer forces a JS garbage collection,
   // so we have to do it ourselves here.
   nsContentUtils::XPConnect()->GarbageCollect();
-  sCollectedObjectsCounts = nsCycleCollector_collect();
+  sCollectedObjectsCounts = nsCycleCollector_collect(aDrawGraph);
   sCCSuspectedCount = nsCycleCollector_suspectedCount();
   sSavedGCCount = JS_GetGCParameter(nsJSRuntime::sRuntime, JSGC_NUMBER);
 #ifdef DEBUG_smaug
@@ -3719,7 +3719,7 @@ nsJSContext::IntervalCC()
 {
   if ((PR_Now() - sPreviousCCTime) >=
       PRTime(NS_MIN_CC_INTERVAL * PR_USEC_PER_MSEC)) {
-    nsJSContext::CC();
+    nsJSContext::CC(PR_FALSE);
     return PR_TRUE;
   }
 #ifdef DEBUG_smaug

dom/base/nsJSEnvironment.h

@@ -188,7 +188,7 @@ public:
 
   // CC does always call cycle collector and it also updates the counters
   // that MaybeCC uses.
-  static void CC();
+  static void CC(PRBool aDrawGraph);
 
   // MaybeCC calls cycle collector if certain conditions are fulfilled.
   // The conditions are:

dom/interfaces/base/nsIDOMWindowUtils.idl

@@ -53,7 +53,7 @@ interface nsIDOMEvent;
 interface nsITransferable;
 interface nsIQueryContentEventResult;
 
-[scriptable, uuid(1e042706-0343-4cba-a549-6a83eefb1835)]
+[scriptable, uuid(bf4df3a0-4567-47ec-be6d-9ec60eaed63c)]
 interface nsIDOMWindowUtils : nsISupports {
 
   /**
@@ -258,8 +258,12 @@ interface nsIDOMWindowUtils : nsISupports {
    *
    * Will throw a DOM security error if called without UniversalXPConnect
    * privileges in non-debug builds. Available to all callers in debug builds.
+   *
+   * @param aDrawGraph when true, a cycle collection graph will be
+   * dumped to a file named cycle-graph-*.dot in the current working
+   * directory
    */
-  void garbageCollect();
+  void garbageCollect(in boolean aDrawGraph);
 
   /**
    * Force processing of any queued paints

xpcom/base/nsCycleCollector.cpp

@@ -156,6 +156,10 @@
 
 //#define COLLECT_TIME_DEBUG
 
+#if defined(DEBUG_CC) || defined(DEBUG)
+#define DEBUG_CC_GRAPHS
+#endif
+
 #ifdef DEBUG_CC
 #define IF_DEBUG_CC_PARAM(_p) , _p
 #define IF_DEBUG_CC_ONLY_PARAM(_p) _p
@@ -177,10 +181,10 @@
 struct nsCycleCollectorParams
 {
     PRBool mDoNothing;
+    PRBool mDrawGraphs;
 #ifdef DEBUG_CC
     PRBool mReportStats;
     PRBool mHookMalloc;
-    PRBool mDrawGraphs;
     PRBool mFaultIsFatal;
     PRBool mLogPointers;
 
@@ -198,7 +202,8 @@ struct nsCycleCollectorParams
 
         mShutdownCollections(DEFAULT_SHUTDOWN_COLLECTIONS)
 #else
-        mDoNothing     (PR_FALSE)
+        mDoNothing     (PR_FALSE),
+        mDrawGraphs    (PR_FALSE)
 #endif
     {
 #ifdef DEBUG_CC
@@ -446,9 +451,12 @@ struct PtrInfo
     EdgePool::Iterator mFirstChild; // first
     EdgePool::Iterator mLastChild; // one after last
 
+#ifdef DEBUG_CC_GRAPHS
+    char *mName;
+#endif
+
 #ifdef DEBUG_CC
     size_t mBytes;
-    char *mName;
     PRUint32 mLangID;
 
     // For finding roots in ExplainLiveExpectedGarbage (when there are
@@ -460,9 +468,9 @@ struct PtrInfo
     ReversedEdge* mReversedEdges; // linked list
     PtrInfo* mShortestPathToExpectedGarbage;
     nsCString* mShortestPathToExpectedGarbageEdgeName;
+#endif
 
     nsTArray<nsCString> mEdgeNames;
-#endif
 
     PtrInfo(void *aPointer, nsCycleCollectionParticipant *aParticipant
             IF_DEBUG_CC_PARAM(PRUint32 aLangID)
@@ -474,9 +482,11 @@ struct PtrInfo
           mRefCount(0),
           mFirstChild(),
           mLastChild()
+#ifdef DEBUG_CC_GRAPHS
+        , mName(nsnull)
+#endif
 #ifdef DEBUG_CC
         , mBytes(0),
-          mName(nsnull),
           mLangID(aLangID),
           mSCCIndex(0),
           mReversedEdges(nsnull),
@@ -486,12 +496,12 @@ struct PtrInfo
     {
     }
 
-#ifdef DEBUG_CC
     void Destroy() {
+#ifdef DEBUG_CC_GRAPHS
         PL_strfree(mName);
+#endif
         mEdgeNames.~nsTArray<nsCString>();
     }
-#endif
 
     // Allow NodePool::Block's constructor to compile.
     PtrInfo() {
@@ -651,7 +661,7 @@ struct GCGraph
 // Add/Remove/Has rather than PutEntry/RemoveEntry/GetEntry.
 typedef nsTHashtable<nsVoidPtrHashKey> PointerSet;
 
-#ifdef DEBUG_CC
+#ifdef DEBUG_CC_GRAPHS
 static void
 WriteGraph(FILE *stream, GCGraph &graph, const void *redPtr);
 #endif
@@ -995,7 +1005,7 @@ struct nsCycleCollector
     nsPurpleBufferEntry* Suspect2(nsISupports *n);
     PRBool Forget2(nsPurpleBufferEntry *e);
 
-    PRUint32 Collect(PRUint32 aTryCollections = 1);
+    PRUint32 Collect(PRUint32 aTryCollections, PRBool aDrawGraph);
     PRBool BeginCollection();
     PRBool FinishCollection();
     PRUint32 SuspectedCount();
@@ -1008,12 +1018,15 @@ struct nsCycleCollector
         mGraph.mRootCount = 0;
     }
 
+#ifdef DEBUG_CC_GRAPHS
+    void MaybeDrawGraphs();
+#endif
+
 #ifdef DEBUG_CC
     nsCycleCollectorStats mStats;    
 
     FILE *mPtrLog;
 
-    void MaybeDrawGraphs();
     void Allocated(void *n, size_t sz);
     void Freed(void *n);
 
@@ -1301,13 +1314,12 @@ private:
     PLDHashTable mPtrToNodeMap;
     PtrInfo *mCurrPi;
     nsCycleCollectionLanguageRuntime **mRuntimes; // weak, from nsCycleCollector
-#ifdef DEBUG_CC
     nsCString mNextEdgeName;
-#endif
 
 public:
     GCGraphBuilder(GCGraph &aGraph,
-                   nsCycleCollectionLanguageRuntime **aRuntimes);
+                   nsCycleCollectionLanguageRuntime **aRuntimes,
+                   PRBool aDrawGraph);
     ~GCGraphBuilder();
     bool Initialized();
 
@@ -1342,7 +1354,8 @@ private:
 };
 
 GCGraphBuilder::GCGraphBuilder(GCGraph &aGraph,
-                               nsCycleCollectionLanguageRuntime **aRuntimes)
+                               nsCycleCollectionLanguageRuntime **aRuntimes,
+                               PRBool aDrawGraph)
     : mNodeBuilder(aGraph.mNodes),
       mEdgeBuilder(aGraph.mEdges),
       mRuntimes(aRuntimes)
@@ -1350,11 +1363,13 @@ GCGraphBuilder::GCGraphBuilder(GCGraph &aGraph,
     if (!PL_DHashTableInit(&mPtrToNodeMap, &PtrNodeOps, nsnull,
                            sizeof(PtrToNodeEntry), 32768))
         mPtrToNodeMap.ops = nsnull;
-#ifdef DEBUG_CC
+#ifndef DEBUG_CC
-    // Do we need to set these all the time?
+    if (aDrawGraph)
-    mFlags |= nsCycleCollectionTraversalCallback::WANT_DEBUG_INFO |
-              nsCycleCollectionTraversalCallback::WANT_ALL_TRACES;
 #endif
+    {
+        mFlags |= nsCycleCollectionTraversalCallback::WANT_DEBUG_INFO |
+                  nsCycleCollectionTraversalCallback::WANT_ALL_TRACES;
+    }
 }
 
 GCGraphBuilder::~GCGraphBuilder()
@@ -1458,7 +1473,11 @@ GCGraphBuilder::DescribeNode(CCNodeType type, nsrefcnt refCount,
 {
 #ifdef DEBUG_CC
     mCurrPi->mBytes = objSz;
-    mCurrPi->mName = PL_strdup(objName);
+#endif
+#ifdef DEBUG_CC_GRAPHS
+    if (WantDebugInfo()) {
+        mCurrPi->mName = PL_strdup(objName);
+    }
 #endif
 
     if (type == RefCounted) {
@@ -1478,10 +1497,11 @@ GCGraphBuilder::DescribeNode(CCNodeType type, nsrefcnt refCount,
 NS_IMETHODIMP_(void)
 GCGraphBuilder::NoteXPCOMChild(nsISupports *child) 
 {
-#ifdef DEBUG_CC
+    nsCString edgeName;
-    nsCString edgeName(mNextEdgeName);
+    if (WantDebugInfo()) {
-    mNextEdgeName.Truncate();
+        edgeName.Assign(mNextEdgeName);
-#endif
+        mNextEdgeName.Truncate();
+    }
     if (!child || !(child = canonicalize(child)))
         return; 
 
@@ -1497,9 +1517,9 @@ GCGraphBuilder::NoteXPCOMChild(nsISupports *child)
         if (!childPi)
             return;
         mEdgeBuilder.Add(childPi);
-#ifdef DEBUG_CC
+        if (WantDebugInfo()) {
-        mCurrPi->mEdgeNames.AppendElement(edgeName);
+            mCurrPi->mEdgeNames.AppendElement(edgeName);
-#endif
+        }
         ++childPi->mInternalRefs;
     }
 }
@@ -1508,10 +1528,11 @@ NS_IMETHODIMP_(void)
 GCGraphBuilder::NoteNativeChild(void *child,
                                 nsCycleCollectionParticipant *participant)
 {
-#ifdef DEBUG_CC
+    nsCString edgeName;
-    nsCString edgeName(mNextEdgeName);
+    if (WantDebugInfo()) {
-    mNextEdgeName.Truncate();
+        edgeName.Assign(mNextEdgeName);
-#endif
+        mNextEdgeName.Truncate();
+    }
     if (!child)
         return;
 
@@ -1521,19 +1542,17 @@ GCGraphBuilder::NoteNativeChild(void *child,
     if (!childPi)
         return;
     mEdgeBuilder.Add(childPi);
-#ifdef DEBUG_CC
+    if (WantDebugInfo()) {
-    mCurrPi->mEdgeNames.AppendElement(edgeName);
+        mCurrPi->mEdgeNames.AppendElement(edgeName);
-#endif
+    }
     ++childPi->mInternalRefs;
 }
 
 NS_IMETHODIMP_(void)
 GCGraphBuilder::NoteScriptChild(PRUint32 langID, void *child) 
 {
-#ifdef DEBUG_CC
     nsCString edgeName(mNextEdgeName);
     mNextEdgeName.Truncate();
-#endif
     if (!child)
         return;
 
@@ -1556,18 +1575,18 @@ GCGraphBuilder::NoteScriptChild(PRUint32 langID, void *child)
     if (!childPi)
         return;
     mEdgeBuilder.Add(childPi);
-#ifdef DEBUG_CC
+    if (WantDebugInfo()) {
-    mCurrPi->mEdgeNames.AppendElement(edgeName);
+        mCurrPi->mEdgeNames.AppendElement(edgeName);
-#endif
+    }
     ++childPi->mInternalRefs;
 }
 
 NS_IMETHODIMP_(void)
 GCGraphBuilder::NoteNextEdgeName(const char* name)
 {
-#ifdef DEBUG_CC
+    if (WantDebugInfo()) {
-    mNextEdgeName = name;
+        mNextEdgeName = name;
-#endif
+    }
 }
 
 static PRBool
@@ -2079,8 +2098,7 @@ nsCycleCollector::ForgetRuntime(PRUint32 langID)
     mRuntimes[langID] = nsnull;
 }
 
-
+#ifdef DEBUG_CC_GRAPHS
-#ifdef DEBUG_CC
 static void
 WriteGraph(FILE *stream, GCGraph &graph, const void *redPtr)
 {
@@ -2108,62 +2126,36 @@ WriteGraph(FILE *stream, GCGraph &graph, const void *redPtr)
                 "\", fillcolor=%s, fontcolor=%s]\n", 
                 (redPtr && redPtr == p ? "red" : (pi->mColor == black ? "black" : "white")),
                 (pi->mColor == black ? "white" : "black"));
+        PRInt32 i = 0;
         for (EdgePool::Iterator child = pi->mFirstChild,
                  child_end = pi->mLastChild;
              child != child_end; ++child) {
-            fprintf(stream, "n%p -> n%p\n", p, (*child)->mPointer);
+            fprintf(stream, "n%p -> n%p [label=\"%s\"]\n", p,
+                    (*child)->mPointer, pi->mEdgeNames[i].get());
+            ++i;
         }
     }
     
     fprintf(stream, "\n}\n");    
 }
 
+static PRUint32 gCounter;
 
 void 
 nsCycleCollector::MaybeDrawGraphs()
 {
     if (mParams.mDrawGraphs) {
-        // We draw graphs only if there were any white nodes.
+        FILE *stream;
-        PRBool anyWhites = PR_FALSE;
+        char name[255];
-        NodePool::Enumerator fwetor(mGraph.mNodes);
+        sprintf(name, "cycle-graph-%d.dot", ++gCounter);
-        while (!fwetor.IsDone())
+        stream = fopen(name, "w");
-        {
+        WriteGraph(stream, mGraph, nsnull);
-            PtrInfo *pinfo = fwetor.GetNext();
+        fclose(stream);
-            if (pinfo->mColor == white) {
-                anyWhites = PR_TRUE;
-                break;
-            }
-        }
-
-        if (anyWhites) {
-            // We can't just use _popen here because graphviz-for-windows
-            // doesn't set up its stdin stream properly, sigh.
-            FILE *stream;
-#ifdef WIN32
-            stream = fopen("c:\\cycle-graph.dot", "w+");
-#else
-            stream = popen("dotty -", "w");
-#endif
-            WriteGraph(stream, mGraph, nsnull);
-#ifdef WIN32
-            fclose(stream);
-            // Even dotty doesn't work terribly well on windows, since
-            // they execute lefty asynchronously. So we'll just run 
-            // lefty ourselves.
-            _spawnlp(_P_WAIT, 
-                     "lefty", 
-                     "lefty",
-                     "-e",
-                     "\"load('dotty.lefty');"
-                     "dotty.simple('c:\\cycle-graph.dot');\"",
-                     NULL);
-            unlink("c:\\cycle-graph.dot");
-#else
-            pclose(stream);
-#endif
-        }
     }
 }
+#endif
+
+#ifdef DEBUG_CC
 
 class Suppressor :
     public nsCycleCollectionTraversalCallback
@@ -2416,7 +2408,7 @@ nsCycleCollector::Freed(void *n)
 #endif
 
 PRUint32
-nsCycleCollector::Collect(PRUint32 aTryCollections)
+nsCycleCollector::Collect(PRUint32 aTryCollections, PRBool aDrawGraph)
 {
 #if defined(DEBUG_CC) && !defined(__MINGW32__)
     if (!mParams.mDoNothing && mParams.mHookMalloc)
@@ -2434,6 +2426,9 @@ nsCycleCollector::Collect(PRUint32 aTryCollections)
     PRTime start = PR_Now();
 #endif
 
+    PRBool drawGraphs = mParams.mDrawGraphs;
+    mParams.mDrawGraphs |= aDrawGraph;
+
     mCollectionInProgress = PR_TRUE;
 
     nsCOMPtr<nsIObserverService> obs =
@@ -2503,6 +2498,8 @@ nsCycleCollector::Collect(PRUint32 aTryCollections)
 
     mCollectionInProgress = PR_FALSE;
 
+    mParams.mDrawGraphs = drawGraphs;
+
 #ifdef XP_OS2
     // Now that the cycle collector has freed some memory, we can try to
     // force the C library to give back as much memory to the system as
@@ -2526,7 +2523,7 @@ nsCycleCollector::BeginCollection()
     if (mParams.mDoNothing)
         return PR_FALSE;
 
-    GCGraphBuilder builder(mGraph, mRuntimes);
+    GCGraphBuilder builder(mGraph, mRuntimes, mParams.mDrawGraphs);
     if (!builder.Initialized())
         return PR_FALSE;
 
@@ -2604,7 +2601,7 @@ nsCycleCollector::BeginCollection()
                (PR_Now() - now) / PR_USEC_PER_MSEC);
 #endif
 
-#ifdef DEBUG_CC
+#ifdef DEBUG_CC_GRAPHS
         MaybeDrawGraphs();
 #endif
 
@@ -2692,7 +2689,7 @@ nsCycleCollector::Shutdown()
             mRuntimes[i]->CommenceShutdown();
     }
 
-    Collect(SHUTDOWN_COLLECTIONS(mParams));
+    Collect(SHUTDOWN_COLLECTIONS(mParams), PR_FALSE);
 
 #ifdef DEBUG_CC
     GCGraphBuilder builder(mGraph, mRuntimes);
@@ -3163,9 +3160,9 @@ NS_CycleCollectorForget2(nsPurpleBufferEntry *e)
 
 
 PRUint32
-nsCycleCollector_collect()
+nsCycleCollector_collect(PRBool aDrawGraph)
 {
-    return sCollector ? sCollector->Collect() : 0;
+    return sCollector ? sCollector->Collect(1, aDrawGraph) : 0;
 }
 
 PRUint32

xpcom/base/nsCycleCollector.h

@@ -63,7 +63,7 @@ struct nsCycleCollectionLanguageRuntime
 
 nsresult nsCycleCollector_startup();
 // Returns the number of collected nodes.
-NS_COM PRUint32 nsCycleCollector_collect();
+NS_COM PRUint32 nsCycleCollector_collect(PRBool aDrawGraph);
 NS_COM PRUint32 nsCycleCollector_suspectedCount();
 void nsCycleCollector_shutdown();