Changeset 20019 in webkit for trunk/JavaScriptCore/kjs

Timestamp:

Mar 7, 2007, 7:37:06 AM (18 years ago)

Author:

ggaren

Message:

JavaScriptCore:

Reviewed by Maciej.

​http://bugs.webkit.org/show_bug.cgi?id=12997

Wrap pthread-specific assertion in #if USE(MULTIPLE_THREADS).

• kjs/collector.cpp: (KJS::Collector::markMainThreadOnlyObjects):

WebCore:

Reviewed by Maciej Stachowiak.

Fixed <rdar://problem/4576242> | ​http://bugs.webkit.org/show_bug.cgi?id=12586
PAC file: malloc deadlock sometimes causes a hang @ www.apple.com/pro/profiles/ (12586)

No test because this is very difficult to repro, and the new ASSERTs in
JavaScriptCore catch the underlying cause while running normal layout tests.

This is a modified version of r14752 on the branch.

The fix is to use a bit inside each node, instead of a hash table, to track
which node subtrees are in the process of being marked. This avoids a call
to malloc inside mark().

• bindings/js/kjs_binding.cpp: (KJS::domObjects): (KJS::domNodesPerDocument):
• bindings/js/kjs_dom.cpp: (KJS::DOMNode::mark):
• dom/Node.cpp: (WebCore::Node::Node):
• dom/Node.h:

File:

• trunk/JavaScriptCore/kjs/collector.cpp (modified) (3 diffs)

trunk/JavaScriptCore/kjs/collector.cpp

@@ -565 +565 @@
 #endif
     
+  // MARK: first mark all referenced objects recursively starting out from the set of root objects
+
+#ifndef NDEBUG
+  // Forbid malloc during the mark phase. Marking a thread suspends it, so 
+  // a malloc inside mark() would risk a deadlock with a thread that had been 
+  // suspended while holding the malloc lock.
+  fastMallocForbid();
+#endif
+
   if (Interpreter::s_hook) {
     Interpreter* scr = Interpreter::s_hook;
@@ -573 +582 @@
   }
 
-  // MARK: first mark all referenced objects recursively starting out from the set of root objects
-
   markStackObjectsConservatively();
   markProtectedObjects();
@@ -580 +587 @@
   if (!currentThreadIsMainThread)
     markMainThreadOnlyObjects();
+
+#ifndef NDEBUG
+  fastMallocAllow();
+#endif
 
   // SWEEP: delete everything with a zero refcount (garbage) and unmark everything else