Changeset 77025 in webkit for trunk/Source/JavaScriptCore/wtf/PageReservation.h

Timestamp:

Jan 28, 2011, 4:35:17 PM (15 years ago)

Author:

[email protected]

Message:

​https://bugs.webkit.org/show_bug.cgi?id=53352
Heavy external fragmentation in FixedVMPoolAllocator can lead to a CRASH().

Reviewed by Geoff Garen.

The FixedVMPoolAllocator currently uses a best fix policy -
switch to first fit, this is less prone to external fragmentation.

• jit/ExecutableAllocatorFixedVMPool.cpp:

(JSC::AllocationTableSizeClass::AllocationTableSizeClass):
(JSC::AllocationTableSizeClass::blockSize):
(JSC::AllocationTableSizeClass::blockCount):
(JSC::AllocationTableSizeClass::blockAlignment):
(JSC::AllocationTableSizeClass::size):
(JSC::AllocationTableLeaf::AllocationTableLeaf):
(JSC::AllocationTableLeaf::~AllocationTableLeaf):
(JSC::AllocationTableLeaf::allocate):
(JSC::AllocationTableLeaf::free):
(JSC::AllocationTableLeaf::isEmpty):
(JSC::AllocationTableLeaf::isFull):
(JSC::AllocationTableLeaf::size):
(JSC::AllocationTableLeaf::classForSize):
(JSC::AllocationTableLeaf::dump):
(JSC::LazyAllocationTable::LazyAllocationTable):
(JSC::LazyAllocationTable::~LazyAllocationTable):
(JSC::LazyAllocationTable::allocate):
(JSC::LazyAllocationTable::free):
(JSC::LazyAllocationTable::isEmpty):
(JSC::LazyAllocationTable::isFull):
(JSC::LazyAllocationTable::size):
(JSC::LazyAllocationTable::dump):
(JSC::LazyAllocationTable::classForSize):
(JSC::AllocationTableDirectory::AllocationTableDirectory):
(JSC::AllocationTableDirectory::~AllocationTableDirectory):
(JSC::AllocationTableDirectory::allocate):
(JSC::AllocationTableDirectory::free):
(JSC::AllocationTableDirectory::isEmpty):
(JSC::AllocationTableDirectory::isFull):
(JSC::AllocationTableDirectory::size):
(JSC::AllocationTableDirectory::classForSize):
(JSC::AllocationTableDirectory::dump):
(JSC::FixedVMPoolAllocator::FixedVMPoolAllocator):
(JSC::FixedVMPoolAllocator::alloc):
(JSC::FixedVMPoolAllocator::free):
(JSC::FixedVMPoolAllocator::allocated):
(JSC::FixedVMPoolAllocator::isValid):
(JSC::FixedVMPoolAllocator::classForSize):
(JSC::FixedVMPoolAllocator::offsetToPointer):
(JSC::FixedVMPoolAllocator::pointerToOffset):
(JSC::ExecutableAllocator::committedByteCount):
(JSC::ExecutableAllocator::isValid):
(JSC::ExecutableAllocator::underMemoryPressure):
(JSC::ExecutablePool::systemAlloc):
(JSC::ExecutablePool::systemRelease):

• wtf/PageReservation.h:

(WTF::PageReservation::PageReservation):
(WTF::PageReservation::commit):
(WTF::PageReservation::decommit):
(WTF::PageReservation::committed):

File:

• trunk/Source/JavaScriptCore/wtf/PageReservation.h (modified) (4 diffs)

trunk/Source/JavaScriptCore/wtf/PageReservation.h

@@ -58 +58 @@
 public:
     PageReservation()
-        : m_writable(false)
+        : m_committed(0)
+        , m_writable(false)
         , m_executable(false)
-#ifndef NDEBUG
-        , m_committed(0)
-#endif
     {
     }
@@ -84 +82 @@
         ASSERT(contains(start, size));
 
-#ifndef NDEBUG
         m_committed += size;
-#endif
         OSAllocator::commit(start, size, m_writable, m_executable);
     }
@@ -97 +93 @@
         ASSERT(contains(start, size));
 
-#ifndef NDEBUG
         m_committed -= size;
-#endif
         OSAllocator::decommit(start, size);
+    }
+
+    size_t committed()
+    {
+        return m_committed;
     }
 
@@ -127 +126 @@
     PageReservation(void* base, size_t size, bool writable, bool executable)
         : PageBlock(base, size)
+        , m_committed(0)
         , m_writable(writable)
         , m_executable(executable)
-#ifndef NDEBUG
-        , m_committed(0)
-#endif
     {
     }
 
+    size_t m_committed;
     bool m_writable;
     bool m_executable;
-#ifndef NDEBUG
-    size_t m_committed;
-#endif
 };