[Oilpan] Set stack limit using estimated sizes

Source/platform/heap/StackFrameDepth.cpp

Index: Source/platform/heap/StackFrameDepth.cpp
diff --git a/Source/platform/heap/StackFrameDepth.cpp b/Source/platform/heap/StackFrameDepth.cpp
index 2d7985a1d3bf9fd1d72f07cb50a8673e3ff6c5eb..95189d39aa0d44946d4b6e50979eb5f273fac817 100644
--- a/Source/platform/heap/StackFrameDepth.cpp
+++ b/Source/platform/heap/StackFrameDepth.cpp
@@ -29,7 +29,17 @@ NEVER_INLINE static uintptr_t currentStackFrameBaseOnCallee(const char* dummy)
 
 void StackFrameDepth::configureLimit()
 {
-    // Allocate a large object in stack and query stack frame pointer after it.
+    static const int kStackRoomSize= 1024;

[kouhei (in TOK), 2015/02/12 03:46:05]

space

+
+    size_t stackSize = getUnderestimatedStackSize();
+    if (stackSize) {
+        size_t stackBase = reinterpret_cast<size_t>(getStackStart());
+        m_stackFrameLimit = stackBase - stackSize + kStackRoomSize;
+        return;
+    }
+
+    // Fallback version
+    // Allocate a 32KB object on stack and query stack frame base after it.
     char dummy[kSafeStackFrameSize];
     m_stackFrameLimit = currentStackFrameBaseOnCallee(dummy);
 
@@ -40,10 +50,30 @@ void StackFrameDepth::configureLimit()
 size_t StackFrameDepth::getUnderestimatedStackSize()
 {
 #if defined(__GLIBC__) || OS(ANDROID) || OS(FREEBSD)
-    // We cannot get the stack size in these platforms because
-    // pthread_getattr_np() can fail for the main thread.
-    // This is OK because ThreadState::current() doesn't use the stack size
-    // in these platforms.
+    // pthread_getattr_np() can fail if the thread is not invoked by
+    // pthread_create() (e.g., the main thread of webkit_unit_tests).
+    // In this case, this method returns 0 and the caller must handle it.
+
+    pthread_attr_t attr;
+    int error;
+#if OS(FREEBSD)
+    pthread_attr_init(&attr);
+    error = pthread_attr_get_np(pthread_self(), &attr);
+#else
+    error = pthread_getattr_np(pthread_self(), &attr);
+#endif
+    if (!error) {
+        void* base;
+        size_t size;
+        error = pthread_attr_getstack(&attr, &base, &size);
+        RELEASE_ASSERT(!error);
+        pthread_attr_destroy(&attr);
+        return size;
+    }
+#if OS(FREEBSD)
+    pthread_attr_destroy(&attr);
+#endif
+
     return 0;
 #elif OS(MACOSX)
     return pthread_get_stacksize_np(pthread_self());
@@ -57,6 +87,7 @@ size_t StackFrameDepth::getUnderestimatedStackSize()
     return __readfsdword(offsetof(NT_TIB, StackBase)) - __readfsdword(offsetof(NT_TIB, StackLimit));
 #endif
 #else
+#error "Stack frame size estimation not supported on this platform."
     return 0;
 #endif
 }