Changeset 74454 in webkit for trunk/JavaScriptCore/runtime/JSGlobalObject.cpp

Timestamp:

Dec 21, 2010, 8:18:58 PM (14 years ago)

Author:

[email protected]

Message:

Reviewed by Geoff Garen.

<rdar://problem/8765333> CRASH running out of executable memory, loading io9.com
​https://bugs.webkit.org/show_bug.cgi?id=51443

The problem here is that each page uses a reasonable amount of memory, (~4Mb),
and that when miultiple pages are open we keep all JIT code for all functions
in all pages alive.

Add a check to detect high memory pressure situations in the executable allocator
(>50% of available memory allocated), and upon a top level entry into JSC (no code
running on the stack) in this situation throw away all JIT code.

• JavaScriptCore.exp:
• debugger/Debugger.cpp:

(JSC::Debugger::recompileAllJSFunctions): stop passing exec to recompile.

• jit/ExecutableAllocator.h:
• jit/ExecutableAllocatorFixedVMPool.cpp:

(JSC::ExecutablePool::systemAlloc): Count allocations.
(JSC::ExecutablePool::systemRelease): Count deallocations.
(JSC::ExecutablePool::underMemoryPressure): Check memory pressure.

• jit/ExecutableAllocatorPosix.cpp:

(JSC::ExecutablePool::underMemoryPressure): Stub out; only meaningful with FixedVMPool.

• jit/ExecutableAllocatorWin.cpp:

(JSC::ExecutablePool::underMemoryPressure): Stub out; only meaningful with FixedVMPool.

• runtime/Executable.cpp:

(JSC::FunctionExecutable::recompile): Remove ExecState argument to recompile.

• runtime/Executable.h:
• runtime/JSGlobalData.cpp:

(JSC::JSGlobalData::recompileAllJSFunctions): throws away all JIT code.

• runtime/JSGlobalData.h:
• runtime/JSGlobalObject.h:

(JSC::DynamicGlobalObjectScope::DynamicGlobalObjectScope): add check / call to throw away.

File:

• trunk/JavaScriptCore/runtime/JSGlobalObject.cpp (modified) (1 diff)

trunk/JavaScriptCore/runtime/JSGlobalObject.cpp

@@ -456 +456 @@
 }
 
+DynamicGlobalObjectScope::DynamicGlobalObjectScope(CallFrame* callFrame, JSGlobalObject* dynamicGlobalObject)
+    : m_dynamicGlobalObjectSlot(callFrame->globalData().dynamicGlobalObject)
+    , m_savedDynamicGlobalObject(m_dynamicGlobalObjectSlot)
+{
+    if (!m_dynamicGlobalObjectSlot) {
+#if ENABLE(ASSEMBLER)
+        if (ExecutableAllocator::underMemoryPressure())
+            callFrame->globalData().recompileAllJSFunctions();
+#endif
+
+        m_dynamicGlobalObjectSlot = dynamicGlobalObject;
+
+        // Reset the date cache between JS invocations to force the VM
+        // to observe time zone changes.
+        callFrame->globalData().resetDateCache();
+    }
+}
+
 } // namespace JSC