Mercurial > hg > graal-compiler
view src/os/windows/vm/threadCritical_windows.cpp @ 17253:b8611b23c4f8
Truffle: Fixed forced inlining decisions could exceed the maximum total node count.
author | Christian Humer <christian.humer@gmail.com> |
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date | Mon, 29 Sep 2014 18:39:05 +0200 |
parents | f34d701e952e |
children |
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/* * Copyright (c) 2001, 2010, 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. * */ #include "precompiled.hpp" #include "runtime/thread.inline.hpp" #include "runtime/threadCritical.hpp" // OS-includes here # include <windows.h> # include <winbase.h> // // See threadCritical.hpp for details of this class. // static bool initialized = false; static volatile jint lock_count = -1; static HANDLE lock_event; static DWORD lock_owner = -1; // // Note that Microsoft's critical region code contains a race // condition, and is not suitable for use. A thread holding the // critical section cannot safely suspend a thread attempting // to enter the critical region. The failure mode is that both // threads are permanently suspended. // // I experiemented with the use of ordinary windows mutex objects // and found them ~30 times slower than the critical region code. // void ThreadCritical::initialize() { } void ThreadCritical::release() { assert(lock_owner == -1, "Mutex being deleted while owned."); assert(lock_count == -1, "Mutex being deleted while recursively locked"); assert(lock_event != NULL, "Sanity check"); CloseHandle(lock_event); } ThreadCritical::ThreadCritical() { DWORD current_thread = GetCurrentThreadId(); if (lock_owner != current_thread) { // Grab the lock before doing anything. while (Atomic::cmpxchg(0, &lock_count, -1) != -1) { if (initialized) { DWORD ret = WaitForSingleObject(lock_event, INFINITE); assert(ret == WAIT_OBJECT_0, "unexpected return value from WaitForSingleObject"); } } // Make sure the event object is allocated. if (!initialized) { // Locking will not work correctly unless this is autoreset. lock_event = CreateEvent(NULL, false, false, NULL); initialized = true; } assert(lock_owner == -1, "Lock acquired illegally."); lock_owner = current_thread; } else { // Atomicity isn't required. Bump the recursion count. lock_count++; } assert(lock_owner == GetCurrentThreadId(), "Lock acquired illegally."); } ThreadCritical::~ThreadCritical() { assert(lock_owner == GetCurrentThreadId(), "unlock attempt by wrong thread"); assert(lock_count >= 0, "Attempt to unlock when already unlocked"); if (lock_count == 0) { // We're going to unlock lock_owner = -1; lock_count = -1; // No lost wakeups, lock_event stays signaled until reset. DWORD ret = SetEvent(lock_event); assert(ret != 0, "unexpected return value from SetEvent"); } else { // Just unwinding a recursive lock; lock_count--; } }