Remove heap protection support.

It does not currently work and when it did work we never got it fast
enough to be useful.

R=kmillikin@chromium.org

Review URL: http://codereview.chromium.org/7324051

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8601 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index 6e13dd2..ecb9b57 100644 (file)
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -491,19 +491,6 @@ DEFINE_string(logfile, "v8.log", "Specify the name of the log file.")
 DEFINE_bool(ll_prof, false, "Enable low-level linux profiler.")
 
 //
-// Heap protection flags
-// Using heap protection requires ENABLE_LOGGING_AND_PROFILING as well.
-//
-#ifdef ENABLE_HEAP_PROTECTION
-#undef FLAG
-#define FLAG FLAG_FULL
-
-DEFINE_bool(protect_heap, false,
-            "Protect/unprotect V8's heap when leaving/entring the VM.")
-
-#endif
-
-//
 // Disassembler only flags
 //
 #undef FLAG

diff --git a/src/handles.cc b/src/handles.cc
index d8cc742..d73aaf0 100644 (file)
--- a/src/handles.cc
+++ b/src/handles.cc
@@ -543,11 +543,6 @@ Handle<Object> SetAccessor(Handle<JSObject> obj, Handle<AccessorInfo> info) {
 // associated with the wrapper and get rid of both the wrapper and the
 // handle.
 static void ClearWrapperCache(Persistent<v8::Value> handle, void*) {
-#ifdef ENABLE_HEAP_PROTECTION
-  // Weak reference callbacks are called as if from outside V8.  We
-  // need to reeenter to unprotect the heap.
-  VMState state(OTHER);
-#endif
   Handle<Object> cache = Utils::OpenHandle(*handle);
   JSValue* wrapper = JSValue::cast(*cache);
   Foreign* foreign = Script::cast(wrapper->value())->wrapper();

diff --git a/src/heap.cc b/src/heap.cc
index 508bdf3..317744e 100644 (file)
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -5213,28 +5213,6 @@ void Heap::Shrink() {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void Heap::Protect() {
-  if (HasBeenSetup()) {
-    AllSpaces spaces;
-    for (Space* space = spaces.next(); space != NULL; space = spaces.next())
-      space->Protect();
-  }
-}
-
-
-void Heap::Unprotect() {
-  if (HasBeenSetup()) {
-    AllSpaces spaces;
-    for (Space* space = spaces.next(); space != NULL; space = spaces.next())
-      space->Unprotect();
-  }
-}
-
-#endif
-
-
 void Heap::AddGCPrologueCallback(GCPrologueCallback callback, GCType gc_type) {
   ASSERT(callback != NULL);
   GCPrologueCallbackPair pair(callback, gc_type);

diff --git a/src/heap.h b/src/heap.h
index 5aba05d..107e5fd 100644 (file)
--- a/src/heap.h
+++ b/src/heap.h
@@ -409,12 +409,6 @@ class Heap {
   // Uncommit unused semi space.
   bool UncommitFromSpace() { return new_space_.UncommitFromSpace(); }
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect the heap by marking all spaces read-only/writable.
-  void Protect();
-  void Unprotect();
-#endif
-
   // Allocates and initializes a new JavaScript object based on a
   // constructor.
   // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation

diff --git a/src/platform-cygwin.cc b/src/platform-cygwin.cc
index 0242f7b..9647ec8 100644 (file)
--- a/src/platform-cygwin.cc
+++ b/src/platform-cygwin.cc
@@ -166,23 +166,6 @@ void OS::Free(void* address, const size_t size) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  // TODO(1240712): mprotect has a return value which is ignored here.
-  mprotect(address, size, PROT_READ);
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  // TODO(1240712): mprotect has a return value which is ignored here.
-  int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
-  mprotect(address, size, prot);
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   unsigned int ms = static_cast<unsigned int>(milliseconds);
   usleep(1000 * ms);

diff --git a/src/platform-freebsd.cc b/src/platform-freebsd.cc
index 755475a..edea930 100644 (file)
--- a/src/platform-freebsd.cc
+++ b/src/platform-freebsd.cc
@@ -181,20 +181,6 @@ void OS::Free(void* buf, const size_t length) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  UNIMPLEMENTED();
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  UNIMPLEMENTED();
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   unsigned int ms = static_cast<unsigned int>(milliseconds);
   usleep(1000 * ms);

diff --git a/src/platform-linux.cc b/src/platform-linux.cc
index d2866ca..e158a5f 100644 (file)
--- a/src/platform-linux.cc
+++ b/src/platform-linux.cc
@@ -390,23 +390,6 @@ void OS::Free(void* address, const size_t size) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  // TODO(1240712): mprotect has a return value which is ignored here.
-  mprotect(address, size, PROT_READ);
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  // TODO(1240712): mprotect has a return value which is ignored here.
-  int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
-  mprotect(address, size, prot);
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   unsigned int ms = static_cast<unsigned int>(milliseconds);
   usleep(1000 * ms);

diff --git a/src/platform-macos.cc b/src/platform-macos.cc
index 104729a..3eb5f89 100644 (file)
--- a/src/platform-macos.cc
+++ b/src/platform-macos.cc
@@ -169,20 +169,6 @@ void OS::Free(void* address, const size_t size) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  UNIMPLEMENTED();
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  UNIMPLEMENTED();
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   usleep(1000 * milliseconds);
 }

diff --git a/src/platform-nullos.cc b/src/platform-nullos.cc
index d309806..9342557 100644 (file)
--- a/src/platform-nullos.cc
+++ b/src/platform-nullos.cc
@@ -217,20 +217,6 @@ void OS::Free(void* buf, const size_t length) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  UNIMPLEMENTED();
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  UNIMPLEMENTED();
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   UNIMPLEMENTED();
 }

diff --git a/src/platform-openbsd.cc b/src/platform-openbsd.cc
index ceabb51..1430b3e 100644 (file)
--- a/src/platform-openbsd.cc
+++ b/src/platform-openbsd.cc
@@ -179,20 +179,6 @@ void OS::Free(void* buf, const size_t length) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  UNIMPLEMENTED();
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  UNIMPLEMENTED();
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   unsigned int ms = static_cast<unsigned int>(milliseconds);
   usleep(1000 * ms);

diff --git a/src/platform-solaris.cc b/src/platform-solaris.cc
index ca15b07..40e0940 100644 (file)
--- a/src/platform-solaris.cc
+++ b/src/platform-solaris.cc
@@ -192,23 +192,6 @@ void OS::Free(void* address, const size_t size) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  // TODO(1240712): mprotect has a return value which is ignored here.
-  mprotect(address, size, PROT_READ);
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  // TODO(1240712): mprotect has a return value which is ignored here.
-  int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
-  mprotect(address, size, prot);
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   useconds_t ms = static_cast<useconds_t>(milliseconds);
   usleep(1000 * ms);

diff --git a/src/platform-win32.cc b/src/platform-win32.cc
index b403b37..49f7c03 100644 (file)
--- a/src/platform-win32.cc
+++ b/src/platform-win32.cc
@@ -939,25 +939,6 @@ void OS::Free(void* address, const size_t size) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void OS::Protect(void* address, size_t size) {
-  // TODO(1240712): VirtualProtect has a return value which is ignored here.
-  DWORD old_protect;
-  VirtualProtect(address, size, PAGE_READONLY, &old_protect);
-}
-
-
-void OS::Unprotect(void* address, size_t size, bool is_executable) {
-  // TODO(1240712): VirtualProtect has a return value which is ignored here.
-  DWORD new_protect = is_executable ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
-  DWORD old_protect;
-  VirtualProtect(address, size, new_protect, &old_protect);
-}
-
-#endif
-
-
 void OS::Sleep(int milliseconds) {
   ::Sleep(milliseconds);
 }

diff --git a/src/platform.h b/src/platform.h
index 06d3ca4..9c3f909 100644 (file)
--- a/src/platform.h
+++ b/src/platform.h
@@ -206,12 +206,6 @@ class OS {
   // Get the Alignment guaranteed by Allocate().
   static size_t AllocateAlignment();
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect a block of memory by marking it read-only/writable.
-  static void Protect(void* address, size_t size);
-  static void Unprotect(void* address, size_t size, bool is_executable);
-#endif
-
   // Returns an indication of whether a pointer is in a space that
   // has been allocated by Allocate().  This method may conservatively
   // always return false, but giving more accurate information may

diff --git a/src/spaces-inl.h b/src/spaces-inl.h
index 070f970..ca1177f 100644 (file)
--- a/src/spaces-inl.h
+++ b/src/spaces-inl.h
@@ -378,35 +378,6 @@ bool MemoryAllocator::InInitialChunk(Address address) {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void MemoryAllocator::Protect(Address start, size_t size) {
-  OS::Protect(start, size);
-}
-
-
-void MemoryAllocator::Unprotect(Address start,
-                                size_t size,
-                                Executability executable) {
-  OS::Unprotect(start, size, executable);
-}
-
-
-void MemoryAllocator::ProtectChunkFromPage(Page* page) {
-  int id = GetChunkId(page);
-  OS::Protect(chunks_[id].address(), chunks_[id].size());
-}
-
-
-void MemoryAllocator::UnprotectChunkFromPage(Page* page) {
-  int id = GetChunkId(page);
-  OS::Unprotect(chunks_[id].address(), chunks_[id].size(),
-                chunks_[id].owner()->executable() == EXECUTABLE);
-}
-
-#endif
-
-
 // --------------------------------------------------------------------------
 // PagedSpace
 

diff --git a/src/spaces.cc b/src/spaces.cc
index 23c87cd..a31194e 100644 (file)
--- a/src/spaces.cc
+++ b/src/spaces.cc
@@ -868,30 +868,6 @@ void PagedSpace::TearDown() {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void PagedSpace::Protect() {
-  Page* page = first_page_;
-  while (page->is_valid()) {
-    Isolate::Current()->memory_allocator()->ProtectChunkFromPage(page);
-    page = Isolate::Current()->memory_allocator()->
-        FindLastPageInSameChunk(page)->next_page();
-  }
-}
-
-
-void PagedSpace::Unprotect() {
-  Page* page = first_page_;
-  while (page->is_valid()) {
-    Isolate::Current()->memory_allocator()->UnprotectChunkFromPage(page);
-    page = Isolate::Current()->memory_allocator()->
-        FindLastPageInSameChunk(page)->next_page();
-  }
-}
-
-#endif
-
-
 void PagedSpace::MarkAllPagesClean() {
   PageIterator it(this, PageIterator::ALL_PAGES);
   while (it.has_next()) {
@@ -1258,24 +1234,6 @@ void NewSpace::TearDown() {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void NewSpace::Protect() {
-  heap()->isolate()->memory_allocator()->Protect(ToSpaceLow(), Capacity());
-  heap()->isolate()->memory_allocator()->Protect(FromSpaceLow(), Capacity());
-}
-
-
-void NewSpace::Unprotect() {
-  heap()->isolate()->memory_allocator()->Unprotect(ToSpaceLow(), Capacity(),
-                                                   to_space_.executable());
-  heap()->isolate()->memory_allocator()->Unprotect(FromSpaceLow(), Capacity(),
-                                                   from_space_.executable());
-}
-
-#endif
-
-
 void NewSpace::Flip() {
   SemiSpace tmp = from_space_;
   from_space_ = to_space_;
@@ -2809,31 +2767,6 @@ void LargeObjectSpace::TearDown() {
 }
 
 
-#ifdef ENABLE_HEAP_PROTECTION
-
-void LargeObjectSpace::Protect() {
-  LargeObjectChunk* chunk = first_chunk_;
-  while (chunk != NULL) {
-    heap()->isolate()->memory_allocator()->Protect(chunk->address(),
-                                                   chunk->size());
-    chunk = chunk->next();
-  }
-}
-
-
-void LargeObjectSpace::Unprotect() {
-  LargeObjectChunk* chunk = first_chunk_;
-  while (chunk != NULL) {
-    bool is_code = chunk->GetObject()->IsCode();
-    heap()->isolate()->memory_allocator()->Unprotect(chunk->address(),
-        chunk->size(), is_code ? EXECUTABLE : NOT_EXECUTABLE);
-    chunk = chunk->next();
-  }
-}
-
-#endif
-
-
 MaybeObject* LargeObjectSpace::AllocateRawInternal(int requested_size,
                                                    int object_size,
                                                    Executability executable) {

diff --git a/src/spaces.h b/src/spaces.h
index 4024387..83f6467 100644 (file)
--- a/src/spaces.h
+++ b/src/spaces.h
@@ -380,12 +380,6 @@ class Space : public Malloced {
   // (e.g. see LargeObjectSpace).
   virtual intptr_t SizeOfObjects() { return Size(); }
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect the space by marking it read-only/writable.
-  virtual void Protect() = 0;
-  virtual void Unprotect() = 0;
-#endif
-
 #ifdef DEBUG
   virtual void Print() = 0;
 #endif
@@ -641,17 +635,6 @@ class MemoryAllocator {
                                   Page** last_page,
                                   Page** last_page_in_use);
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect a block of memory by marking it read-only/writable.
-  inline void Protect(Address start, size_t size);
-  inline void Unprotect(Address start, size_t size,
-                        Executability executable);
-
-  // Protect/unprotect a chunk given a page in the chunk.
-  inline void ProtectChunkFromPage(Page* page);
-  inline void UnprotectChunkFromPage(Page* page);
-#endif
-
 #ifdef DEBUG
   // Reports statistic info of the space.
   void ReportStatistics();
@@ -1157,12 +1140,6 @@ class PagedSpace : public Space {
   // Ensures that the capacity is at least 'capacity'. Returns false on failure.
   bool EnsureCapacity(int capacity);
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect the space by marking it read-only/writable.
-  void Protect();
-  void Unprotect();
-#endif
-
 #ifdef DEBUG
   // Print meta info and objects in this space.
   virtual void Print();
@@ -1392,12 +1369,6 @@ class SemiSpace : public Space {
   bool Commit();
   bool Uncommit();
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect the space by marking it read-only/writable.
-  virtual void Protect() {}
-  virtual void Unprotect() {}
-#endif
-
 #ifdef DEBUG
   virtual void Print();
   virtual void Verify();
@@ -1628,12 +1599,6 @@ class NewSpace : public Space {
   template <typename StringType>
   inline void ShrinkStringAtAllocationBoundary(String* string, int len);
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect the space by marking it read-only/writable.
-  virtual void Protect();
-  virtual void Unprotect();
-#endif
-
 #ifdef DEBUG
   // Verify the active semispace.
   virtual void Verify();
@@ -2296,12 +2261,6 @@ class LargeObjectSpace : public Space {
   // may use some memory, leaving less for large objects.
   virtual bool ReserveSpace(int bytes);
 
-#ifdef ENABLE_HEAP_PROTECTION
-  // Protect/unprotect the space by marking it read-only/writable.
-  void Protect();
-  void Unprotect();
-#endif
-
 #ifdef DEBUG
   virtual void Verify();
   virtual void Print();

diff --git a/src/vm-state-inl.h b/src/vm-state-inl.h
index 1f363de..c1afeaf 100644 (file)
--- a/src/vm-state-inl.h
+++ b/src/vm-state-inl.h
@@ -69,19 +69,6 @@ VMState::VMState(Isolate* isolate, StateTag tag)
 #endif
 
   isolate_->SetCurrentVMState(tag);
-
-#ifdef ENABLE_HEAP_PROTECTION
-  if (FLAG_protect_heap) {
-    if (tag == EXTERNAL) {
-      // We are leaving V8.
-      ASSERT(previous_tag_ != EXTERNAL);
-      isolate_->heap()->Protect();
-    } else if (previous_tag_ = EXTERNAL) {
-      // We are entering V8.
-      isolate_->heap()->Unprotect();
-    }
-  }
-#endif
 }
 
 
@@ -96,24 +83,7 @@ VMState::~VMState() {
   }
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
-#ifdef ENABLE_HEAP_PROTECTION
-  StateTag tag = isolate_->current_vm_state();
-#endif
-
   isolate_->SetCurrentVMState(previous_tag_);
-
-#ifdef ENABLE_HEAP_PROTECTION
-  if (FLAG_protect_heap) {
-    if (tag == EXTERNAL) {
-      // We are reentering V8.
-      ASSERT(previous_tag_ != EXTERNAL);
-      isolate_->heap()->Unprotect();
-    } else if (previous_tag_ == EXTERNAL) {
-      // We are leaving V8.
-      isolate_->heap()->Protect();
-    }
-  }
-#endif  // ENABLE_HEAP_PROTECTION
 }
 
 #endif  // ENABLE_VMSTATE_TRACKING