--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/runtime/interfaceSupport.hpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,568 @@
+/*
+ * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// Wrapper for all entry points to the virtual machine.
+// The HandleMarkCleaner is a faster version of HandleMark.
+// It relies on the fact that there is a HandleMark further
+// down the stack (in JavaCalls::call_helper), and just resets
+// to the saved values in that HandleMark.
+
+class HandleMarkCleaner: public StackObj {
+ private:
+ Thread* _thread;
+ public:
+ HandleMarkCleaner(Thread* thread) {
+ _thread = thread;
+ _thread->last_handle_mark()->push();
+ }
+ ~HandleMarkCleaner() {
+ _thread->last_handle_mark()->pop_and_restore();
+ }
+
+ private:
+ inline void* operator new(size_t size, void* ptr) {
+ return ptr;
+ }
+};
+
+// InterfaceSupport provides functionality used by the __LEAF and __ENTRY
+// macros. These macros are used to guard entry points into the VM and
+// perform checks upon leave of the VM.
+
+
+class InterfaceSupport: AllStatic {
+# ifdef ASSERT
+ public:
+ static long _scavenge_alot_counter;
+ static long _fullgc_alot_counter;
+ static long _number_of_calls;
+ static long _fullgc_alot_invocation;
+
+ // tracing
+ static void trace(const char* result_type, const char* header);
+
+ // Helper methods used to implement +ScavengeALot and +FullGCALot
+ static void check_gc_alot() { if (ScavengeALot || FullGCALot) gc_alot(); }
+ static void gc_alot();
+
+ static void walk_stack_from(vframe* start_vf);
+ static void walk_stack();
+
+# ifdef ENABLE_ZAP_DEAD_LOCALS
+ static void zap_dead_locals_old();
+# endif
+
+ static void zombieAll();
+ static void deoptimizeAll();
+ static void stress_derived_pointers();
+ static void verify_stack();
+ static void verify_last_frame();
+# endif
+
+ public:
+ // OS dependent stuff
+ #include "incls/_interfaceSupport_pd.hpp.incl"
+};
+
+
+// Basic class for all thread transition classes.
+
+class ThreadStateTransition : public StackObj {
+ protected:
+ JavaThread* _thread;
+ public:
+ ThreadStateTransition(JavaThread *thread) {
+ _thread = thread;
+ assert(thread != NULL && thread->is_Java_thread(), "must be Java thread");
+ }
+
+ // Change threadstate in a manner, so safepoint can detect changes.
+ // Time-critical: called on exit from every runtime routine
+ static inline void transition(JavaThread *thread, JavaThreadState from, JavaThreadState to) {
+ assert(from != _thread_in_Java, "use transition_from_java");
+ assert(from != _thread_in_native, "use transition_from_native");
+ assert((from & 1) == 0 && (to & 1) == 0, "odd numbers are transitions states");
+ assert(thread->thread_state() == from, "coming from wrong thread state");
+ // Change to transition state (assumes total store ordering! -Urs)
+ thread->set_thread_state((JavaThreadState)(from + 1));
+
+ // Make sure new state is seen by VM thread
+ if (os::is_MP()) {
+ if (UseMembar) {
+ // Force a fence between the write above and read below
+ OrderAccess::fence();
+ } else {
+ // store to serialize page so VM thread can do pseudo remote membar
+ os::write_memory_serialize_page(thread);
+ }
+ }
+
+ if (SafepointSynchronize::do_call_back()) {
+ SafepointSynchronize::block(thread);
+ }
+ thread->set_thread_state(to);
+
+ CHECK_UNHANDLED_OOPS_ONLY(thread->clear_unhandled_oops();)
+ }
+
+ // transition_and_fence must be used on any thread state transition
+ // where there might not be a Java call stub on the stack, in
+ // particular on Windows where the Structured Exception Handler is
+ // set up in the call stub. os::write_memory_serialize_page() can
+ // fault and we can't recover from it on Windows without a SEH in
+ // place.
+ static inline void transition_and_fence(JavaThread *thread, JavaThreadState from, JavaThreadState to) {
+ assert(thread->thread_state() == from, "coming from wrong thread state");
+ assert((from & 1) == 0 && (to & 1) == 0, "odd numbers are transitions states");
+ // Change to transition state (assumes total store ordering! -Urs)
+ thread->set_thread_state((JavaThreadState)(from + 1));
+
+ // Make sure new state is seen by VM thread
+ if (os::is_MP()) {
+ if (UseMembar) {
+ // Force a fence between the write above and read below
+ OrderAccess::fence();
+ } else {
+ // Must use this rather than serialization page in particular on Windows
+ InterfaceSupport::serialize_memory(thread);
+ }
+ }
+
+ if (SafepointSynchronize::do_call_back()) {
+ SafepointSynchronize::block(thread);
+ }
+ thread->set_thread_state(to);
+
+ CHECK_UNHANDLED_OOPS_ONLY(thread->clear_unhandled_oops();)
+ }
+
+ // Same as above, but assumes from = _thread_in_Java. This is simpler, since we
+ // never block on entry to the VM. This will break the code, since e.g. preserve arguments
+ // have not been setup.
+ static inline void transition_from_java(JavaThread *thread, JavaThreadState to) {
+ assert(thread->thread_state() == _thread_in_Java, "coming from wrong thread state");
+ thread->set_thread_state(to);
+ }
+
+ static inline void transition_from_native(JavaThread *thread, JavaThreadState to) {
+ assert((to & 1) == 0, "odd numbers are transitions states");
+ assert(thread->thread_state() == _thread_in_native, "coming from wrong thread state");
+ // Change to transition state (assumes total store ordering! -Urs)
+ thread->set_thread_state(_thread_in_native_trans);
+
+ // Make sure new state is seen by GC thread
+ if (os::is_MP()) {
+ if (UseMembar) {
+ // Force a fence between the write above and read below
+ OrderAccess::fence();
+ } else {
+ // Must use this rather than serialization page in particular on Windows
+ InterfaceSupport::serialize_memory(thread);
+ }
+ }
+
+ // We never install asynchronous exceptions when coming (back) in
+ // to the runtime from native code because the runtime is not set
+ // up to handle exceptions floating around at arbitrary points.
+ if (SafepointSynchronize::do_call_back() || thread->is_suspend_after_native()) {
+ JavaThread::check_safepoint_and_suspend_for_native_trans(thread);
+
+ // Clear unhandled oops anywhere where we could block, even if we don't.
+ CHECK_UNHANDLED_OOPS_ONLY(thread->clear_unhandled_oops();)
+ }
+
+ thread->set_thread_state(to);
+ }
+ protected:
+ void trans(JavaThreadState from, JavaThreadState to) { transition(_thread, from, to); }
+ void trans_from_java(JavaThreadState to) { transition_from_java(_thread, to); }
+ void trans_from_native(JavaThreadState to) { transition_from_native(_thread, to); }
+ void trans_and_fence(JavaThreadState from, JavaThreadState to) { transition_and_fence(_thread, from, to); }
+};
+
+
+class ThreadInVMfromJava : public ThreadStateTransition {
+ public:
+ ThreadInVMfromJava(JavaThread* thread) : ThreadStateTransition(thread) {
+ trans_from_java(_thread_in_vm);
+ }
+ ~ThreadInVMfromJava() {
+ trans(_thread_in_vm, _thread_in_Java);
+ // Check for pending. async. exceptions or suspends.
+ if (_thread->has_special_runtime_exit_condition()) _thread->handle_special_runtime_exit_condition();
+ }
+};
+
+
+class ThreadInVMfromUnknown {
+ private:
+ JavaThread* _thread;
+ public:
+ ThreadInVMfromUnknown() : _thread(NULL) {
+ Thread* t = Thread::current();
+ if (t->is_Java_thread()) {
+ JavaThread* t2 = (JavaThread*) t;
+ if (t2->thread_state() == _thread_in_native) {
+ _thread = t2;
+ ThreadStateTransition::transition_from_native(t2, _thread_in_vm);
+ // Used to have a HandleMarkCleaner but that is dangerous as
+ // it could free a handle in our (indirect, nested) caller.
+ // We expect any handles will be short lived and figure we
+ // don't need an actual HandleMark.
+ }
+ }
+ }
+ ~ThreadInVMfromUnknown() {
+ if (_thread) {
+ ThreadStateTransition::transition_and_fence(_thread, _thread_in_vm, _thread_in_native);
+ }
+ }
+};
+
+
+class ThreadInVMfromNative : public ThreadStateTransition {
+ public:
+ ThreadInVMfromNative(JavaThread* thread) : ThreadStateTransition(thread) {
+ trans_from_native(_thread_in_vm);
+ }
+ ~ThreadInVMfromNative() {
+ trans_and_fence(_thread_in_vm, _thread_in_native);
+ }
+};
+
+
+class ThreadToNativeFromVM : public ThreadStateTransition {
+ public:
+ ThreadToNativeFromVM(JavaThread *thread) : ThreadStateTransition(thread) {
+ // We are leaving the VM at this point and going directly to native code.
+ // Block, if we are in the middle of a safepoint synchronization.
+ assert(!thread->owns_locks(), "must release all locks when leaving VM");
+ thread->frame_anchor()->make_walkable(thread);
+ trans_and_fence(_thread_in_vm, _thread_in_native);
+ // Check for pending. async. exceptions or suspends.
+ if (_thread->has_special_runtime_exit_condition()) _thread->handle_special_runtime_exit_condition(false);
+ }
+
+ ~ThreadToNativeFromVM() {
+ trans_from_native(_thread_in_vm);
+ // We don't need to clear_walkable because it will happen automagically when we return to java
+ }
+};
+
+
+class ThreadBlockInVM : public ThreadStateTransition {
+ public:
+ ThreadBlockInVM(JavaThread *thread)
+ : ThreadStateTransition(thread) {
+ // Once we are blocked vm expects stack to be walkable
+ thread->frame_anchor()->make_walkable(thread);
+ trans_and_fence(_thread_in_vm, _thread_blocked);
+ }
+ ~ThreadBlockInVM() {
+ trans_and_fence(_thread_blocked, _thread_in_vm);
+ // We don't need to clear_walkable because it will happen automagically when we return to java
+ }
+};
+
+
+// This special transition class is only used to prevent asynchronous exceptions
+// from being installed on vm exit in situations where we can't tolerate them.
+// See bugs: 4324348, 4854693, 4998314, 5040492, 5050705.
+class ThreadInVMfromJavaNoAsyncException : public ThreadStateTransition {
+ public:
+ ThreadInVMfromJavaNoAsyncException(JavaThread* thread) : ThreadStateTransition(thread) {
+ trans_from_java(_thread_in_vm);
+ }
+ ~ThreadInVMfromJavaNoAsyncException() {
+ trans(_thread_in_vm, _thread_in_Java);
+ // NOTE: We do not check for pending. async. exceptions.
+ // If we did and moved the pending async exception over into the
+ // pending exception field, we would need to deopt (currently C2
+ // only). However, to do so would require that we transition back
+ // to the _thread_in_vm state. Instead we postpone the handling of
+ // the async exception.
+
+ // Check for pending. suspends only.
+ if (_thread->has_special_runtime_exit_condition())
+ _thread->handle_special_runtime_exit_condition(false);
+ }
+};
+
+// Debug class instantiated in JRT_ENTRY and ITR_ENTRY macro.
+// Can be used to verify properties on enter/exit of the VM.
+
+#ifdef ASSERT
+class VMEntryWrapper {
+ public:
+ VMEntryWrapper() {
+ if (VerifyLastFrame) {
+ InterfaceSupport::verify_last_frame();
+ }
+ }
+
+ ~VMEntryWrapper() {
+ InterfaceSupport::check_gc_alot();
+ if (WalkStackALot) {
+ InterfaceSupport::walk_stack();
+ }
+#ifdef ENABLE_ZAP_DEAD_LOCALS
+ if (ZapDeadLocalsOld) {
+ InterfaceSupport::zap_dead_locals_old();
+ }
+#endif
+#ifdef COMPILER2
+ // This option is not used by Compiler 1
+ if (StressDerivedPointers) {
+ InterfaceSupport::stress_derived_pointers();
+ }
+#endif
+ if (DeoptimizeALot || DeoptimizeRandom) {
+ InterfaceSupport::deoptimizeAll();
+ }
+ if (ZombieALot) {
+ InterfaceSupport::zombieAll();
+ }
+ // do verification AFTER potential deoptimization
+ if (VerifyStack) {
+ InterfaceSupport::verify_stack();
+ }
+
+ }
+};
+
+
+class VMNativeEntryWrapper {
+ public:
+ VMNativeEntryWrapper() {
+ if (GCALotAtAllSafepoints) InterfaceSupport::check_gc_alot();
+ }
+
+ ~VMNativeEntryWrapper() {
+ if (GCALotAtAllSafepoints) InterfaceSupport::check_gc_alot();
+ }
+};
+
+#endif
+
+
+// VM-internal runtime interface support
+
+#ifdef ASSERT
+
+class RuntimeHistogramElement : public HistogramElement {
+ public:
+ RuntimeHistogramElement(const char* name);
+};
+
+#define TRACE_CALL(result_type, header) \
+ InterfaceSupport::_number_of_calls++; \
+ if (TraceRuntimeCalls) \
+ InterfaceSupport::trace(#result_type, #header); \
+ if (CountRuntimeCalls) { \
+ static RuntimeHistogramElement* e = new RuntimeHistogramElement(#header); \
+ if (e != NULL) e->increment_count(); \
+ }
+#else
+#define TRACE_CALL(result_type, header) \
+ /* do nothing */
+#endif
+
+
+// LEAF routines do not lock, GC or throw exceptions
+
+#define __LEAF(result_type, header) \
+ TRACE_CALL(result_type, header) \
+ debug_only(NoHandleMark __hm;) \
+ /* begin of body */
+
+
+// ENTRY routines may lock, GC and throw exceptions
+
+#define __ENTRY(result_type, header, thread) \
+ TRACE_CALL(result_type, header) \
+ HandleMarkCleaner __hm(thread); \
+ Thread* THREAD = thread; \
+ /* begin of body */
+
+
+// QUICK_ENTRY routines behave like ENTRY but without a handle mark
+
+#define __QUICK_ENTRY(result_type, header, thread) \
+ TRACE_CALL(result_type, header) \
+ debug_only(NoHandleMark __hm;) \
+ Thread* THREAD = thread; \
+ /* begin of body */
+
+
+// Definitions for IRT (Interpreter Runtime)
+// (thread is an argument passed in to all these routines)
+
+#define IRT_ENTRY(result_type, header) \
+ result_type header { \
+ ThreadInVMfromJava __tiv(thread); \
+ __ENTRY(result_type, header, thread) \
+ debug_only(VMEntryWrapper __vew;)
+
+
+#define IRT_LEAF(result_type, header) \
+ result_type header { \
+ __LEAF(result_type, header) \
+ debug_only(No_Safepoint_Verifier __nspv(true);)
+
+
+#define IRT_ENTRY_NO_ASYNC(result_type, header) \
+ result_type header { \
+ ThreadInVMfromJavaNoAsyncException __tiv(thread); \
+ __ENTRY(result_type, header, thread) \
+ debug_only(VMEntryWrapper __vew;)
+
+// Another special case for nmethod_entry_point so the nmethod that the
+// interpreter is about to branch to doesn't get flushed before as we
+// branch to it's interpreter_entry_point. Skip stress testing here too.
+// Also we don't allow async exceptions because it is just too painful.
+#define IRT_ENTRY_FOR_NMETHOD(result_type, header) \
+ result_type header { \
+ nmethodLocker _nmlock(nm); \
+ ThreadInVMfromJavaNoAsyncException __tiv(thread); \
+ __ENTRY(result_type, header, thread)
+
+#define IRT_END }
+
+
+// Definitions for JRT (Java (Compiler/Shared) Runtime)
+
+#define JRT_ENTRY(result_type, header) \
+ result_type header { \
+ ThreadInVMfromJava __tiv(thread); \
+ __ENTRY(result_type, header, thread) \
+ debug_only(VMEntryWrapper __vew;)
+
+
+#define JRT_LEAF(result_type, header) \
+ result_type header { \
+ __LEAF(result_type, header) \
+ debug_only(JRT_Leaf_Verifier __jlv;)
+
+
+#define JRT_ENTRY_NO_ASYNC(result_type, header) \
+ result_type header { \
+ ThreadInVMfromJavaNoAsyncException __tiv(thread); \
+ __ENTRY(result_type, header, thread) \
+ debug_only(VMEntryWrapper __vew;)
+
+// Same as JRT Entry but allows for return value after the safepoint
+// to get back into Java from the VM
+#define JRT_BLOCK_ENTRY(result_type, header) \
+ result_type header { \
+ TRACE_CALL(result_type, header) \
+ HandleMarkCleaner __hm(thread);
+
+#define JRT_BLOCK \
+ { \
+ ThreadInVMfromJava __tiv(thread); \
+ Thread* THREAD = thread; \
+ debug_only(VMEntryWrapper __vew;)
+
+#define JRT_BLOCK_END }
+
+#define JRT_END }
+
+// Definitions for JNI
+
+#define JNI_ENTRY(result_type, header) \
+ JNI_ENTRY_NO_PRESERVE(result_type, header) \
+ WeakPreserveExceptionMark __wem(thread);
+
+#define JNI_ENTRY_NO_PRESERVE(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ JavaThread* thread=JavaThread::thread_from_jni_environment(env); \
+ assert( !VerifyJNIEnvThread || (thread == Thread::current()), "JNIEnv is only valid in same thread"); \
+ ThreadInVMfromNative __tiv(thread); \
+ debug_only(VMNativeEntryWrapper __vew;) \
+ __ENTRY(result_type, header, thread)
+
+
+// Ensure that the VMNativeEntryWrapper constructor, which can cause
+// a GC, is called outside the NoHandleMark (set via __QUICK_ENTRY).
+#define JNI_QUICK_ENTRY(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ JavaThread* thread=JavaThread::thread_from_jni_environment(env); \
+ assert( !VerifyJNIEnvThread || (thread == Thread::current()), "JNIEnv is only valid in same thread"); \
+ ThreadInVMfromNative __tiv(thread); \
+ debug_only(VMNativeEntryWrapper __vew;) \
+ __QUICK_ENTRY(result_type, header, thread)
+
+
+#define JNI_LEAF(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ JavaThread* thread=JavaThread::thread_from_jni_environment(env); \
+ assert( !VerifyJNIEnvThread || (thread == Thread::current()), "JNIEnv is only valid in same thread"); \
+ __LEAF(result_type, header)
+
+
+// Close the routine and the extern "C"
+#define JNI_END } }
+
+
+
+// Definitions for JVM
+
+#define JVM_ENTRY(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ JavaThread* thread=JavaThread::thread_from_jni_environment(env); \
+ ThreadInVMfromNative __tiv(thread); \
+ debug_only(VMNativeEntryWrapper __vew;) \
+ __ENTRY(result_type, header, thread)
+
+
+#define JVM_ENTRY_NO_ENV(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ JavaThread* thread = (JavaThread*)ThreadLocalStorage::thread(); \
+ ThreadInVMfromNative __tiv(thread); \
+ debug_only(VMNativeEntryWrapper __vew;) \
+ __ENTRY(result_type, header, thread)
+
+
+#define JVM_QUICK_ENTRY(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ JavaThread* thread=JavaThread::thread_from_jni_environment(env); \
+ ThreadInVMfromNative __tiv(thread); \
+ debug_only(VMNativeEntryWrapper __vew;) \
+ __QUICK_ENTRY(result_type, header, thread)
+
+
+#define JVM_LEAF(result_type, header) \
+extern "C" { \
+ result_type JNICALL header { \
+ VM_Exit::block_if_vm_exited(); \
+ __LEAF(result_type, header)
+
+
+#define JVM_END } }