src/hotspot/share/runtime/interfaceSupport.inline.hpp
changeset 49449 ef5d5d343e2a
parent 47881 0ce0ac68ace7
child 49488 1f9dd2360b17
child 49594 898ef81cbc0e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/interfaceSupport.inline.hpp	Fri Mar 16 09:12:13 2018 -0400
@@ -0,0 +1,571 @@
+/*
+ * Copyright (c) 1997, 2017, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_RUNTIME_INTERFACESUPPORT_INLINE_HPP
+#define SHARE_VM_RUNTIME_INTERFACESUPPORT_INLINE_HPP
+
+#include "gc/shared/gcLocker.hpp"
+#include "runtime/handles.inline.hpp"
+#include "runtime/mutexLocker.hpp"
+#include "runtime/orderAccess.hpp"
+#include "runtime/os.hpp"
+#include "runtime/safepointMechanism.inline.hpp"
+#include "runtime/thread.hpp"
+#include "runtime/vm_operations.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/macros.hpp"
+#include "utilities/preserveException.hpp"
+
+// Wrapper for all entry points to the virtual machine.
+
+// InterfaceSupport provides functionality used by the VM_LEAF_BASE and
+// VM_ENTRY_BASE 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;
+
+  // 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();
+
+  static void zombieAll();
+  static void unlinkSymbols();
+  static void deoptimizeAll();
+  static void stress_derived_pointers();
+  static void verify_stack();
+  static void verify_last_frame();
+# endif
+
+ public:
+  static void serialize_thread_state_with_handler(JavaThread* thread) {
+    serialize_thread_state_internal(thread, true);
+  }
+
+  // Should only call this if we know that we have a proper SEH set up.
+  static void serialize_thread_state(JavaThread* thread) {
+    serialize_thread_state_internal(thread, false);
+  }
+
+ private:
+  static void serialize_thread_state_internal(JavaThread* thread, bool needs_exception_handler) {
+    // 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
+        if (needs_exception_handler) {
+          os::write_memory_serialize_page_with_handler(thread);
+        } else {
+          os::write_memory_serialize_page(thread);
+        }
+      }
+    }
+  }
+};
+
+
+// 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
+    thread->set_thread_state((JavaThreadState)(from + 1));
+
+    InterfaceSupport::serialize_thread_state(thread);
+
+    SafepointMechanism::block_if_requested(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
+    thread->set_thread_state((JavaThreadState)(from + 1));
+
+    InterfaceSupport::serialize_thread_state_with_handler(thread);
+
+    SafepointMechanism::block_if_requested(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
+    thread->set_thread_state(_thread_in_native_trans);
+
+    InterfaceSupport::serialize_thread_state_with_handler(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 (SafepointMechanism::poll(thread) || 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 ThreadInVMForHandshake : public ThreadStateTransition {
+  const JavaThreadState _original_state;
+
+  void transition_back() {
+    // This can be invoked from transition states and must return to the original state properly
+    assert(_thread->thread_state() == _thread_in_vm, "should only call when leaving VM after handshake");
+    _thread->set_thread_state(_thread_in_vm_trans);
+
+    InterfaceSupport::serialize_thread_state(_thread);
+
+    SafepointMechanism::block_if_requested(_thread);
+
+    _thread->set_thread_state(_original_state);
+  }
+
+ public:
+
+  ThreadInVMForHandshake(JavaThread* thread) : ThreadStateTransition(thread),
+      _original_state(thread->thread_state()) {
+
+    if (thread->has_last_Java_frame()) {
+      thread->frame_anchor()->make_walkable(thread);
+    }
+
+    thread->set_thread_state(_thread_in_vm);
+  }
+
+  ~ThreadInVMForHandshake() {
+    transition_back();
+  }
+
+};
+
+class ThreadInVMfromJava : public ThreadStateTransition {
+ public:
+  ThreadInVMfromJava(JavaThread* thread) : ThreadStateTransition(thread) {
+    trans_from_java(_thread_in_vm);
+  }
+  ~ThreadInVMfromJava()  {
+    if (_thread->stack_yellow_reserved_zone_disabled()) {
+      _thread->enable_stack_yellow_reserved_zone();
+    }
+    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);
+    assert(!_thread->is_pending_jni_exception_check(), "Pending JNI Exception Check");
+    // 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()  {
+    if (_thread->stack_yellow_reserved_zone_disabled()) {
+      _thread->enable_stack_yellow_reserved_zone();
+    }
+    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();
+  ~VMEntryWrapper();
+};
+
+
+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 (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 VM_LEAF_BASE(result_type, header)                            \
+  TRACE_CALL(result_type, header)                                    \
+  debug_only(NoHandleMark __hm;)                                     \
+  os::verify_stack_alignment();                                      \
+  /* begin of body */
+
+#define VM_ENTRY_BASE_FROM_LEAF(result_type, header, thread)         \
+  TRACE_CALL(result_type, header)                                    \
+  debug_only(ResetNoHandleMark __rnhm;)                              \
+  HandleMarkCleaner __hm(thread);                                    \
+  Thread* THREAD = thread;                                           \
+  os::verify_stack_alignment();                                      \
+  /* begin of body */
+
+
+// ENTRY routines may lock, GC and throw exceptions
+
+#define VM_ENTRY_BASE(result_type, header, thread)                   \
+  TRACE_CALL(result_type, header)                                    \
+  HandleMarkCleaner __hm(thread);                                    \
+  Thread* THREAD = thread;                                           \
+  os::verify_stack_alignment();                                      \
+  /* begin of body */
+
+
+// QUICK_ENTRY routines behave like ENTRY but without a handle mark
+
+#define VM_QUICK_ENTRY_BASE(result_type, header, thread)             \
+  TRACE_CALL(result_type, header)                                    \
+  debug_only(NoHandleMark __hm;)                                     \
+  Thread* THREAD = thread;                                           \
+  os::verify_stack_alignment();                                      \
+  /* 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);                                \
+    VM_ENTRY_BASE(result_type, header, thread)                       \
+    debug_only(VMEntryWrapper __vew;)
+
+
+#define IRT_LEAF(result_type, header)                                \
+  result_type header {                                               \
+    VM_LEAF_BASE(result_type, header)                                \
+    debug_only(NoSafepointVerifier __nspv(true);)
+
+
+#define IRT_ENTRY_NO_ASYNC(result_type, header)                      \
+  result_type header {                                               \
+    ThreadInVMfromJavaNoAsyncException __tiv(thread);                \
+    VM_ENTRY_BASE(result_type, header, thread)                       \
+    debug_only(VMEntryWrapper __vew;)
+
+#define IRT_END }
+
+
+// Definitions for JRT (Java (Compiler/Shared) Runtime)
+
+#define JRT_ENTRY(result_type, header)                               \
+  result_type header {                                               \
+    ThreadInVMfromJava __tiv(thread);                                \
+    VM_ENTRY_BASE(result_type, header, thread)                       \
+    debug_only(VMEntryWrapper __vew;)
+
+
+#define JRT_LEAF(result_type, header)                                \
+  result_type header {                                               \
+  VM_LEAF_BASE(result_type, header)                                  \
+  debug_only(JRTLeafVerifier __jlv;)
+
+
+#define JRT_ENTRY_NO_ASYNC(result_type, header)                      \
+  result_type header {                                               \
+    ThreadInVMfromJavaNoAsyncException __tiv(thread);                \
+    VM_ENTRY_BASE(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_NO_ASYNC                                           \
+    {                                                                \
+    ThreadInVMfromJavaNoAsyncException __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;)                          \
+    VM_ENTRY_BASE(result_type, header, thread)
+
+
+// Ensure that the VMNativeEntryWrapper constructor, which can cause
+// a GC, is called outside the NoHandleMark (set via VM_QUICK_ENTRY_BASE).
+#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;)                          \
+    VM_QUICK_ENTRY_BASE(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"); \
+    VM_LEAF_BASE(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;)                          \
+    VM_ENTRY_BASE(result_type, header, thread)
+
+
+#define JVM_ENTRY_NO_ENV(result_type, header)                        \
+extern "C" {                                                         \
+  result_type JNICALL header {                                       \
+    JavaThread* thread = JavaThread::current();                      \
+    ThreadInVMfromNative __tiv(thread);                              \
+    debug_only(VMNativeEntryWrapper __vew;)                          \
+    VM_ENTRY_BASE(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;)                          \
+    VM_QUICK_ENTRY_BASE(result_type, header, thread)
+
+
+#define JVM_LEAF(result_type, header)                                \
+extern "C" {                                                         \
+  result_type JNICALL header {                                       \
+    VM_Exit::block_if_vm_exited();                                   \
+    VM_LEAF_BASE(result_type, header)
+
+
+#define JVM_ENTRY_FROM_LEAF(env, result_type, header)                \
+  { {                                                                \
+    JavaThread* thread=JavaThread::thread_from_jni_environment(env); \
+    ThreadInVMfromNative __tiv(thread);                              \
+    debug_only(VMNativeEntryWrapper __vew;)                          \
+    VM_ENTRY_BASE_FROM_LEAF(result_type, header, thread)
+
+
+#define JVM_END } }
+
+#endif // SHARE_VM_RUNTIME_INTERFACESUPPORT_INLINE_HPP