PKGBUILDs/extra/webkit2gtk/0001-Merge-r214319-JSC-MachineThreads-does-not-consider-s.patch
2017-04-24 19:14:49 +00:00

390 lines
16 KiB
Diff

From 70c605847496766b0ca59bee03ecadb74e54a159 Mon Sep 17 00:00:00 2001
From: "carlosgc@webkit.org"
<carlosgc@webkit.org@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Date: Tue, 4 Apr 2017 16:12:17 +0000
Subject: [PATCH] Merge r214319 - [JSC] MachineThreads does not consider
situation that one thread has multiple VMs
https://bugs.webkit.org/show_bug.cgi?id=169819
Reviewed by Mark Lam.
The Linux port of PlatformThread suspend/resume mechanism relies on having a thread
specific singleton thread data, and was relying on MachineThreads::Thread to be this
thread specific singleton. But because MachineThreads::Thread is not a thread specific
singleton, we can get a deadlock in the GTK port's DatabaseProcess.
This patch fixes this issue by moving per thread data from MachineThreads::Thread to
MachineThreads::ThreadData, where there will only be one instance of
MachineThreads::ThreadData per thread. Each MachineThreads::Thread will now point to
the same MachineThreads::ThreadData for any given thread.
* heap/MachineStackMarker.cpp:
(pthreadSignalHandlerSuspendResume):
(JSC::threadData):
(JSC::MachineThreads::Thread::Thread):
(JSC::MachineThreads::Thread::createForCurrentThread):
(JSC::MachineThreads::Thread::operator==):
(JSC::MachineThreads::ThreadData::ThreadData):
(JSC::MachineThreads::ThreadData::~ThreadData):
(JSC::MachineThreads::ThreadData::suspend):
(JSC::MachineThreads::ThreadData::resume):
(JSC::MachineThreads::ThreadData::getRegisters):
(JSC::MachineThreads::ThreadData::Registers::stackPointer):
(JSC::MachineThreads::ThreadData::Registers::framePointer):
(JSC::MachineThreads::ThreadData::Registers::instructionPointer):
(JSC::MachineThreads::ThreadData::Registers::llintPC):
(JSC::MachineThreads::ThreadData::freeRegisters):
(JSC::MachineThreads::ThreadData::captureStack):
(JSC::MachineThreads::tryCopyOtherThreadStacks):
(JSC::MachineThreads::Thread::~Thread): Deleted.
(JSC::MachineThreads::Thread::suspend): Deleted.
(JSC::MachineThreads::Thread::resume): Deleted.
(JSC::MachineThreads::Thread::getRegisters): Deleted.
(JSC::MachineThreads::Thread::Registers::stackPointer): Deleted.
(JSC::MachineThreads::Thread::Registers::framePointer): Deleted.
(JSC::MachineThreads::Thread::Registers::instructionPointer): Deleted.
(JSC::MachineThreads::Thread::Registers::llintPC): Deleted.
(JSC::MachineThreads::Thread::freeRegisters): Deleted.
(JSC::MachineThreads::Thread::captureStack): Deleted.
* heap/MachineStackMarker.h:
(JSC::MachineThreads::Thread::operator!=):
(JSC::MachineThreads::Thread::suspend):
(JSC::MachineThreads::Thread::resume):
(JSC::MachineThreads::Thread::getRegisters):
(JSC::MachineThreads::Thread::freeRegisters):
(JSC::MachineThreads::Thread::captureStack):
(JSC::MachineThreads::Thread::platformThread):
(JSC::MachineThreads::Thread::stackBase):
(JSC::MachineThreads::Thread::stackEnd):
* runtime/SamplingProfiler.cpp:
(JSC::FrameWalker::isValidFramePointer):
* runtime/VMTraps.cpp:
(JSC::findActiveVMAndStackBounds):
git-svn-id: http://svn.webkit.org/repository/webkit/releases/WebKitGTK/webkit-2.16@214882 268f45cc-cd09-0410-ab3c-d52691b4dbfc
---
Source/JavaScriptCore/heap/MachineStackMarker.cpp | 73 +++++++++++++---------
Source/JavaScriptCore/heap/MachineStackMarker.h | 41 +++++++++---
Source/JavaScriptCore/runtime/SamplingProfiler.cpp | 4 +-
4 files changed, 137 insertions(+), 41 deletions(-)
diff --git a/Source/JavaScriptCore/heap/MachineStackMarker.cpp b/Source/JavaScriptCore/heap/MachineStackMarker.cpp
index 65eb0cf0d9b..5fea745d2ad 100644
--- a/Source/JavaScriptCore/heap/MachineStackMarker.cpp
+++ b/Source/JavaScriptCore/heap/MachineStackMarker.cpp
@@ -33,6 +33,7 @@
#include <setjmp.h>
#include <stdlib.h>
#include <wtf/MainThread.h>
+#include <wtf/NeverDestroyed.h>
#include <wtf/StdLibExtras.h>
#if OS(DARWIN)
@@ -69,14 +70,14 @@
// We use SIGUSR2 to suspend and resume machine threads in JavaScriptCore.
static const int SigThreadSuspendResume = SIGUSR2;
static StaticLock globalSignalLock;
-thread_local static std::atomic<JSC::MachineThreads::Thread*> threadLocalCurrentThread;
+thread_local static std::atomic<JSC::MachineThreads::ThreadData*> threadLocalCurrentThread { nullptr };
static void pthreadSignalHandlerSuspendResume(int, siginfo_t*, void* ucontext)
{
// Touching thread local atomic types from signal handlers is allowed.
- JSC::MachineThreads::Thread* thread = threadLocalCurrentThread.load();
+ JSC::MachineThreads::ThreadData* threadData = threadLocalCurrentThread.load();
- if (thread->suspended.load(std::memory_order_acquire)) {
+ if (threadData->suspended.load(std::memory_order_acquire)) {
// This is signal handler invocation that is intended to be used to resume sigsuspend.
// So this handler invocation itself should not process.
//
@@ -88,9 +89,9 @@ static void pthreadSignalHandlerSuspendResume(int, siginfo_t*, void* ucontext)
ucontext_t* userContext = static_cast<ucontext_t*>(ucontext);
#if CPU(PPC)
- thread->suspendedMachineContext = *userContext->uc_mcontext.uc_regs;
+ threadData->suspendedMachineContext = *userContext->uc_mcontext.uc_regs;
#else
- thread->suspendedMachineContext = userContext->uc_mcontext;
+ threadData->suspendedMachineContext = userContext->uc_mcontext;
#endif
// Allow suspend caller to see that this thread is suspended.
@@ -99,7 +100,7 @@ static void pthreadSignalHandlerSuspendResume(int, siginfo_t*, void* ucontext)
//
// And sem_post emits memory barrier that ensures that suspendedMachineContext is correctly saved.
// http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_11
- sem_post(&thread->semaphoreForSuspendResume);
+ sem_post(&threadData->semaphoreForSuspendResume);
// Reaching here, SigThreadSuspendResume is blocked in this handler (this is configured by sigaction's sa_mask).
// So before calling sigsuspend, SigThreadSuspendResume to this thread is deferred. This ensures that the handler is not executed recursively.
@@ -109,7 +110,7 @@ static void pthreadSignalHandlerSuspendResume(int, siginfo_t*, void* ucontext)
sigsuspend(&blockedSignalSet);
// Allow resume caller to see that this thread is resumed.
- sem_post(&thread->semaphoreForSuspendResume);
+ sem_post(&threadData->semaphoreForSuspendResume);
}
#endif // USE(PTHREADS) && !OS(WINDOWS) && !OS(DARWIN)
@@ -215,18 +216,29 @@ MachineThreads::~MachineThreads()
}
}
+static MachineThreads::ThreadData* threadData()
+{
+ static NeverDestroyed<ThreadSpecific<MachineThreads::ThreadData, CanBeGCThread::True>> threadData;
+ return threadData.get();
+}
+
+MachineThreads::Thread::Thread(ThreadData* threadData)
+ : data(threadData)
+{
+ ASSERT(threadData);
+}
+
Thread* MachineThreads::Thread::createForCurrentThread()
{
- auto stackBounds = wtfThreadData().stack();
- return new Thread(getCurrentPlatformThread(), stackBounds.origin(), stackBounds.end());
+ return new Thread(threadData());
}
bool MachineThreads::Thread::operator==(const PlatformThread& other) const
{
#if OS(DARWIN) || OS(WINDOWS)
- return platformThread == other;
+ return data->platformThread == other;
#elif USE(PTHREADS)
- return !!pthread_equal(platformThread, other);
+ return !!pthread_equal(data->platformThread, other);
#else
#error Need a way to compare threads on this platform
#endif
@@ -325,11 +337,13 @@ void MachineThreads::gatherFromCurrentThread(ConservativeRoots& conservativeRoot
conservativeRoots.add(currentThreadState.stackTop, currentThreadState.stackOrigin, jitStubRoutines, codeBlocks);
}
-MachineThreads::Thread::Thread(const PlatformThread& platThread, void* base, void* end)
- : platformThread(platThread)
- , stackBase(base)
- , stackEnd(end)
+MachineThreads::ThreadData::ThreadData()
{
+ auto stackBounds = wtfThreadData().stack();
+ platformThread = getCurrentPlatformThread();
+ stackBase = stackBounds.origin();
+ stackEnd = stackBounds.end();
+
#if OS(WINDOWS)
ASSERT(platformThread == GetCurrentThreadId());
bool isSuccessful =
@@ -362,7 +376,7 @@ MachineThreads::Thread::Thread(const PlatformThread& platThread, void* base, voi
#endif
}
-MachineThreads::Thread::~Thread()
+MachineThreads::ThreadData::~ThreadData()
{
#if OS(WINDOWS)
CloseHandle(platformThreadHandle);
@@ -371,7 +385,7 @@ MachineThreads::Thread::~Thread()
#endif
}
-bool MachineThreads::Thread::suspend()
+bool MachineThreads::ThreadData::suspend()
{
#if OS(DARWIN)
kern_return_t result = thread_suspend(platformThread);
@@ -408,7 +422,7 @@ bool MachineThreads::Thread::suspend()
#endif
}
-void MachineThreads::Thread::resume()
+void MachineThreads::ThreadData::resume()
{
#if OS(DARWIN)
thread_resume(platformThread);
@@ -439,9 +453,9 @@ void MachineThreads::Thread::resume()
#endif
}
-size_t MachineThreads::Thread::getRegisters(Thread::Registers& registers)
+size_t MachineThreads::ThreadData::getRegisters(ThreadData::Registers& registers)
{
- Thread::Registers::PlatformRegisters& regs = registers.regs;
+ ThreadData::Registers::PlatformRegisters& regs = registers.regs;
#if OS(DARWIN)
#if CPU(X86)
unsigned user_count = sizeof(regs)/sizeof(int);
@@ -496,7 +510,7 @@ size_t MachineThreads::Thread::getRegisters(Thread::Registers& registers)
#endif
}
-void* MachineThreads::Thread::Registers::stackPointer() const
+void* MachineThreads::ThreadData::Registers::stackPointer() const
{
#if OS(DARWIN)
@@ -601,7 +615,7 @@ void* MachineThreads::Thread::Registers::stackPointer() const
}
#if ENABLE(SAMPLING_PROFILER)
-void* MachineThreads::Thread::Registers::framePointer() const
+void* MachineThreads::ThreadData::Registers::framePointer() const
{
#if OS(DARWIN)
@@ -684,7 +698,7 @@ void* MachineThreads::Thread::Registers::framePointer() const
#endif
}
-void* MachineThreads::Thread::Registers::instructionPointer() const
+void* MachineThreads::ThreadData::Registers::instructionPointer() const
{
#if OS(DARWIN)
@@ -765,7 +779,8 @@ void* MachineThreads::Thread::Registers::instructionPointer() const
#error Need a way to get the instruction pointer for another thread on this platform
#endif
}
-void* MachineThreads::Thread::Registers::llintPC() const
+
+void* MachineThreads::ThreadData::Registers::llintPC() const
{
// LLInt uses regT4 as PC.
#if OS(DARWIN)
@@ -858,9 +873,9 @@ void* MachineThreads::Thread::Registers::llintPC() const
}
#endif // ENABLE(SAMPLING_PROFILER)
-void MachineThreads::Thread::freeRegisters(Thread::Registers& registers)
+void MachineThreads::ThreadData::freeRegisters(ThreadData::Registers& registers)
{
- Thread::Registers::PlatformRegisters& regs = registers.regs;
+ ThreadData::Registers::PlatformRegisters& regs = registers.regs;
#if USE(PTHREADS) && !OS(WINDOWS) && !OS(DARWIN)
pthread_attr_destroy(&regs.attribute);
#else
@@ -883,7 +898,7 @@ static inline int osRedZoneAdjustment()
return redZoneAdjustment;
}
-std::pair<void*, size_t> MachineThreads::Thread::captureStack(void* stackTop)
+std::pair<void*, size_t> MachineThreads::ThreadData::captureStack(void* stackTop)
{
char* begin = reinterpret_cast_ptr<char*>(stackBase);
char* end = bitwise_cast<char*>(WTF::roundUpToMultipleOf<sizeof(void*)>(reinterpret_cast<uintptr_t>(stackTop)));
@@ -971,12 +986,12 @@ bool MachineThreads::tryCopyOtherThreadStacks(LockHolder&, void* buffer, size_t
}
// Re-do the suspension to get the actual failure result for logging.
- kern_return_t error = thread_suspend(thread->platformThread);
+ kern_return_t error = thread_suspend(thread->platformThread());
ASSERT(error != KERN_SUCCESS);
WTFReportError(__FILE__, __LINE__, WTF_PRETTY_FUNCTION,
"JavaScript garbage collection encountered an invalid thread (err 0x%x): Thread [%d/%d: %p] platformThread %p.",
- error, index, numberOfThreads, thread, reinterpret_cast<void*>(thread->platformThread));
+ error, index, numberOfThreads, thread, reinterpret_cast<void*>(thread->platformThread()));
// Put the invalid thread on the threadsToBeDeleted list.
// We can't just delete it here because we have suspended other
diff --git a/Source/JavaScriptCore/heap/MachineStackMarker.h b/Source/JavaScriptCore/heap/MachineStackMarker.h
index a5a50870922..da979c582ec 100644
--- a/Source/JavaScriptCore/heap/MachineStackMarker.h
+++ b/Source/JavaScriptCore/heap/MachineStackMarker.h
@@ -74,14 +74,13 @@ public:
JS_EXPORT_PRIVATE void addCurrentThread(); // Only needs to be called by clients that can use the same heap from multiple threads.
- class Thread {
+ class ThreadData {
WTF_MAKE_FAST_ALLOCATED;
- Thread(const PlatformThread& platThread, void* base, void* end);
-
public:
- ~Thread();
+ ThreadData();
+ ~ThreadData();
- static Thread* createForCurrentThread();
+ static ThreadData* createForCurrentThread();
struct Registers {
void* stackPointer() const;
@@ -118,12 +117,9 @@ public:
#else
#error Need a thread register struct for this platform
#endif
-
+
PlatformRegisters regs;
};
-
- bool operator==(const PlatformThread& other) const;
- bool operator!=(const PlatformThread& other) const { return !(*this == other); }
bool suspend();
void resume();
@@ -131,7 +127,6 @@ public:
void freeRegisters(Registers&);
std::pair<void*, size_t> captureStack(void* stackTop);
- Thread* next;
PlatformThread platformThread;
void* stackBase;
void* stackEnd;
@@ -145,6 +140,32 @@ public:
#endif
};
+ class Thread {
+ WTF_MAKE_FAST_ALLOCATED;
+ Thread(ThreadData*);
+
+ public:
+ using Registers = ThreadData::Registers;
+
+ static Thread* createForCurrentThread();
+
+ bool operator==(const PlatformThread& other) const;
+ bool operator!=(const PlatformThread& other) const { return !(*this == other); }
+
+ bool suspend() { return data->suspend(); }
+ void resume() { data->resume(); }
+ size_t getRegisters(Registers& regs) { return data->getRegisters(regs); }
+ void freeRegisters(Registers& regs) { data->freeRegisters(regs); }
+ std::pair<void*, size_t> captureStack(void* stackTop) { return data->captureStack(stackTop); }
+
+ const PlatformThread& platformThread() { return data->platformThread; }
+ void* stackBase() const { return data->stackBase; }
+ void* stackEnd() const { return data->stackEnd; }
+
+ Thread* next;
+ ThreadData* data;
+ };
+
Lock& getLock() { return m_registeredThreadsMutex; }
Thread* threadsListHead(const LockHolder&) const { ASSERT(m_registeredThreadsMutex.isLocked()); return m_registeredThreads; }
Thread* machineThreadForCurrentThread();
diff --git a/Source/JavaScriptCore/runtime/SamplingProfiler.cpp b/Source/JavaScriptCore/runtime/SamplingProfiler.cpp
index a8d953d6622..9326d7a0fc9 100644
--- a/Source/JavaScriptCore/runtime/SamplingProfiler.cpp
+++ b/Source/JavaScriptCore/runtime/SamplingProfiler.cpp
@@ -169,8 +169,8 @@ protected:
{
uint8_t* fpCast = bitwise_cast<uint8_t*>(exec);
for (MachineThreads::Thread* thread = m_vm.heap.machineThreads().threadsListHead(m_machineThreadsLocker); thread; thread = thread->next) {
- uint8_t* stackBase = static_cast<uint8_t*>(thread->stackBase);
- uint8_t* stackLimit = static_cast<uint8_t*>(thread->stackEnd);
+ uint8_t* stackBase = static_cast<uint8_t*>(thread->stackBase());
+ uint8_t* stackLimit = static_cast<uint8_t*>(thread->stackEnd());
RELEASE_ASSERT(stackBase);
RELEASE_ASSERT(stackLimit);
if (fpCast <= stackBase && fpCast >= stackLimit)
--
2.12.2