From c09656dc258fc8c1818fad1b984134a2a0fb48d6 Mon Sep 17 00:00:00 2001 From: "reed@reedloden.com" Date: Fri, 1 Feb 2008 17:17:03 -0800 Subject: [PATCH] Bug 400450 - "Deadlock in nsProxyObject::Release" (testcase to show deadlock) [p=mook.moz+mozbz@gmail.com (Mook) r=bsmedberg] --- xpcom/proxy/tests/Makefile.in | 4 +- .../proxy/tests/proxy-create-threadsafety.cpp | 260 ++++++++++++++++++ 2 files changed, 263 insertions(+), 1 deletion(-) create mode 100644 xpcom/proxy/tests/proxy-create-threadsafety.cpp diff --git a/xpcom/proxy/tests/Makefile.in b/xpcom/proxy/tests/Makefile.in index 12c90043ac6f..55490e5d81e3 100644 --- a/xpcom/proxy/tests/Makefile.in +++ b/xpcom/proxy/tests/Makefile.in @@ -46,7 +46,9 @@ MODULE = xpcom_tests XPIDL_MODULE = proxytest REQUIRES = xpcom -CPPSRCS = proxytests.cpp +CPPSRCS = proxytests.cpp \ + proxy-create-threadsafety.cpp \ + $(NULL) XPIDLSRCS = nsITestProxy.idl SIMPLE_PROGRAMS = $(CPPSRCS:.cpp=$(BIN_SUFFIX)) diff --git a/xpcom/proxy/tests/proxy-create-threadsafety.cpp b/xpcom/proxy/tests/proxy-create-threadsafety.cpp new file mode 100644 index 000000000000..4e6b5c3fa265 --- /dev/null +++ b/xpcom/proxy/tests/proxy-create-threadsafety.cpp @@ -0,0 +1,260 @@ +/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* ***** BEGIN LICENSE BLOCK ***** + * Version: MPL 1.1/GPL 2.0/LGPL 2.1 + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + * + * The Original Code is mozilla.org code. + * + * The Initial Developer of the Original Code is + * Mark 'Mook' Yen + * Portions created by the Initial Developer are Copyright (C) 2008 + * the Initial Developer. All Rights Reserved. + * + * Contributor(s): + * + * Alternatively, the contents of this file may be used under the terms of + * either of the GNU General Public License Version 2 or later (the "GPL"), + * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), + * in which case the provisions of the GPL or the LGPL are applicable instead + * of those above. If you wish to allow use of your version of this file only + * under the terms of either the GPL or the LGPL, and not to allow others to + * use your version of this file under the terms of the MPL, indicate your + * decision by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL or the LGPL. If you do not delete + * the provisions above, a recipient may use your version of this file under + * the terms of any one of the MPL, the GPL or the LGPL. + * + * ***** END LICENSE BLOCK ***** */ + +#include + +#include "nsXPCOM.h" +#include "nsXPCOMCIDInternal.h" +#include "nsIComponentManager.h" +#include "nsIComponentRegistrar.h" +#include "nsIServiceManager.h" +#include "nsAutoPtr.h" +#include "nsAutoLock.h" +#include "nsCOMPtr.h" + +#include "nscore.h" +#include "nspr.h" +#include "prmon.h" + +#include "nsITestProxy.h" +#include "nsISupportsPrimitives.h" + +#include "nsIRunnable.h" +#include "nsIProxyObjectManager.h" +#include "nsXPCOMCIDInternal.h" +#include "nsComponentManagerUtils.h" +#include "nsServiceManagerUtils.h" +#include "nsThreadUtils.h" +#include "nsISupportsUtils.h" + +/* + +A quick diagram of how this test works: + +This tests for bug 400450, where the creation of a proxy event object +causes a deadlock. We use a counter and a monitor to make things +be more deterministic. + +The leftmost column marks the thread that is running. + +M Create two threads +1 Get a proxy +1 proxy event object created +1 (Proxy object QIs the target) +1 Lock [*] +2 Get a proxy +2 proxy event object created +2 (Proxy object calls QI) +2 Unlock [*] +2 proxy event object stored +2 proxy obtained +1 proxy event object released + + + */ + +/***************************************************************************/ +/* ProxyTest */ +/***************************************************************************/ + +class ProxyTest : public nsIRunnable, + public nsITestProxy, + public nsISupportsPrimitive +{ +public: + ProxyTest() + : mCounter(0) + {} + + NS_IMETHOD Run() + { + nsresult rv; + nsCOMPtr pom = + do_GetService(NS_XPCOMPROXY_CONTRACTID, &rv); + NS_ENSURE_SUCCESS(rv, rv); + + nsCOMPtr prim; + rv = pom->GetProxyForObject(NS_PROXY_TO_MAIN_THREAD, + NS_GET_IID(nsISupportsPrimitive), + NS_ISUPPORTS_CAST(nsIRunnable*, this), + NS_PROXY_SYNC | NS_PROXY_ALWAYS, + getter_AddRefs(prim)); + NS_ENSURE_SUCCESS(rv, rv); + /* we don't actually need to use the proxied object */ + return NS_OK; + } + + NS_IMETHOD Test(PRInt32 p1, PRInt32 p2, PRInt32 *_retval) + { + nsresult rv; + + if (!NS_IsMainThread()) + return NS_ERROR_UNEXPECTED; + + mCounterLock = nsAutoLock::NewLock(__FILE__ " counter lock"); + NS_ENSURE_TRUE(mCounterLock, NS_ERROR_OUT_OF_MEMORY); + mEvilMonitor = nsAutoMonitor::NewMonitor(__FILE__ " evil monitor"); + NS_ENSURE_TRUE(mEvilMonitor, NS_ERROR_OUT_OF_MEMORY); + + /* note that we don't have an event queue... */ + + rv = NS_NewThread(getter_AddRefs(mThreadOne), + static_cast(this)); + NS_ENSURE_SUCCESS(rv, rv); + rv = NS_NewThread(getter_AddRefs(mThreadTwo), + static_cast(this)); + NS_ENSURE_SUCCESS(rv, rv); + + rv = mThreadOne->Shutdown(); + NS_ENSURE_SUCCESS(rv, rv); + rv = mThreadTwo->Shutdown(); + NS_ENSURE_SUCCESS(rv, rv); + + return NS_OK; + } + + NS_IMETHOD Test2(void) + { + return NS_ERROR_NOT_IMPLEMENTED; + } + + NS_IMETHOD Test3(nsISupports *p1, nsISupports **p2) + { + return NS_ERROR_NOT_IMPLEMENTED; + } + + NS_IMETHOD GetType(PRUint16 *_retval) + { + return NS_ERROR_NOT_IMPLEMENTED; + } + + NS_IMETHOD QueryInterface(REFNSIID aIID, void** aInstancePtr) + { + NS_ASSERTION(aInstancePtr, + "QueryInterface requires a non-NULL destination!"); + nsISupports* foundInterface; + if ( aIID.Equals(NS_GET_IID(nsIRunnable)) ) { + foundInterface = static_cast(this); + } else if ( aIID.Equals(NS_GET_IID(nsITestProxy)) ) { + foundInterface = static_cast(this); + } else if ( aIID.Equals(NS_GET_IID(nsISupports)) ) { + foundInterface = NS_ISUPPORTS_CAST(nsIRunnable*, this); + } else if ( aIID.Equals(NS_GET_IID(nsISupportsPrimitive)) ) { + { + nsAutoLock counterLock(mCounterLock); + switch(mCounter) { + case 0: + ++mCounter; + { + /* be evil here and hang */ + nsAutoUnlock counterUnlock(mCounterLock); + nsAutoMonitor evilMonitor(mEvilMonitor); + nsresult rv = evilMonitor.Wait(); + NS_ENSURE_SUCCESS(rv, rv); + break; + } + case 1: + ++mCounter; + { + /* okay, we had our fun, un-hang */ + nsAutoUnlock counterUnlock(mCounterLock); + nsAutoMonitor evilMonitor(mEvilMonitor); + nsresult rv = evilMonitor.Notify(); + NS_ENSURE_SUCCESS(rv, rv); + break; + } + default: { + /* nothing special here */ + ++mCounter; + } + } + ++mCounter; + } + // remeber to admit to supporting this interface + foundInterface = static_cast(this); + } else { + foundInterface = nsnull; + } + nsresult status; + if (!foundInterface) { + status = NS_ERROR_NO_INTERFACE; + } else { + NS_ADDREF(foundInterface); + status = NS_OK; + } + *aInstancePtr = foundInterface; + return status; + } + + NS_IMETHOD_(nsrefcnt) AddRef(void); + NS_IMETHOD_(nsrefcnt) Release(void); + +protected: + nsAutoRefCnt mRefCnt; + NS_DECL_OWNINGTHREAD + +private: + PRLock* mCounterLock; + PRMonitor* mEvilMonitor; + PRInt32 mCounter; + nsCOMPtr mThreadOne; + nsCOMPtr mThreadTwo; +}; + +NS_IMPL_THREADSAFE_ADDREF(ProxyTest) +NS_IMPL_THREADSAFE_RELEASE(ProxyTest) + +int +main(int argc, char **argv) +{ + NS_InitXPCOM2(nsnull, nsnull, nsnull); + + // Scope code so everything is destroyed before we run call NS_ShutdownXPCOM + { + nsCOMPtr registrar; + NS_GetComponentRegistrar(getter_AddRefs(registrar)); + registrar->AutoRegister(nsnull); + + nsCOMPtr tester = new ProxyTest(); + tester->Test(0, 0, nsnull); + } + + NS_ShutdownXPCOM(nsnull); + + return 0; +} +