33d6b93e22
Reviewed-by: coleenp, twisti
4682 lines
165 KiB
C++
4682 lines
165 KiB
C++
/*
|
|
* Copyright (c) 1997, 2013, 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 "classfile/classLoader.hpp"
|
|
#include "classfile/javaClasses.hpp"
|
|
#include "classfile/systemDictionary.hpp"
|
|
#include "classfile/vmSymbols.hpp"
|
|
#include "code/scopeDesc.hpp"
|
|
#include "compiler/compileBroker.hpp"
|
|
#include "interpreter/interpreter.hpp"
|
|
#include "interpreter/linkResolver.hpp"
|
|
#include "interpreter/oopMapCache.hpp"
|
|
#include "jvmtifiles/jvmtiEnv.hpp"
|
|
#include "memory/gcLocker.inline.hpp"
|
|
#include "memory/metaspaceShared.hpp"
|
|
#include "memory/oopFactory.hpp"
|
|
#include "memory/universe.inline.hpp"
|
|
#include "oops/instanceKlass.hpp"
|
|
#include "oops/objArrayOop.hpp"
|
|
#include "oops/oop.inline.hpp"
|
|
#include "oops/symbol.hpp"
|
|
#include "prims/jvm_misc.hpp"
|
|
#include "prims/jvmtiExport.hpp"
|
|
#include "prims/jvmtiThreadState.hpp"
|
|
#include "prims/privilegedStack.hpp"
|
|
#include "runtime/arguments.hpp"
|
|
#include "runtime/biasedLocking.hpp"
|
|
#include "runtime/deoptimization.hpp"
|
|
#include "runtime/fprofiler.hpp"
|
|
#include "runtime/frame.inline.hpp"
|
|
#include "runtime/init.hpp"
|
|
#include "runtime/interfaceSupport.hpp"
|
|
#include "runtime/java.hpp"
|
|
#include "runtime/javaCalls.hpp"
|
|
#include "runtime/jniPeriodicChecker.hpp"
|
|
#include "runtime/memprofiler.hpp"
|
|
#include "runtime/mutexLocker.hpp"
|
|
#include "runtime/objectMonitor.hpp"
|
|
#include "runtime/osThread.hpp"
|
|
#include "runtime/safepoint.hpp"
|
|
#include "runtime/sharedRuntime.hpp"
|
|
#include "runtime/statSampler.hpp"
|
|
#include "runtime/stubRoutines.hpp"
|
|
#include "runtime/task.hpp"
|
|
#include "runtime/thread.inline.hpp"
|
|
#include "runtime/threadCritical.hpp"
|
|
#include "runtime/threadLocalStorage.hpp"
|
|
#include "runtime/vframe.hpp"
|
|
#include "runtime/vframeArray.hpp"
|
|
#include "runtime/vframe_hp.hpp"
|
|
#include "runtime/vmThread.hpp"
|
|
#include "runtime/vm_operations.hpp"
|
|
#include "services/attachListener.hpp"
|
|
#include "services/management.hpp"
|
|
#include "services/memTracker.hpp"
|
|
#include "services/threadService.hpp"
|
|
#include "trace/tracing.hpp"
|
|
#include "trace/traceMacros.hpp"
|
|
#include "utilities/defaultStream.hpp"
|
|
#include "utilities/dtrace.hpp"
|
|
#include "utilities/events.hpp"
|
|
#include "utilities/preserveException.hpp"
|
|
#include "utilities/macros.hpp"
|
|
#ifdef TARGET_OS_FAMILY_linux
|
|
# include "os_linux.inline.hpp"
|
|
#endif
|
|
#ifdef TARGET_OS_FAMILY_solaris
|
|
# include "os_solaris.inline.hpp"
|
|
#endif
|
|
#ifdef TARGET_OS_FAMILY_windows
|
|
# include "os_windows.inline.hpp"
|
|
#endif
|
|
#ifdef TARGET_OS_FAMILY_bsd
|
|
# include "os_bsd.inline.hpp"
|
|
#endif
|
|
#if INCLUDE_ALL_GCS
|
|
#include "gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp"
|
|
#include "gc_implementation/g1/concurrentMarkThread.inline.hpp"
|
|
#include "gc_implementation/parallelScavenge/pcTasks.hpp"
|
|
#endif // INCLUDE_ALL_GCS
|
|
#ifdef COMPILER1
|
|
#include "c1/c1_Compiler.hpp"
|
|
#endif
|
|
#ifdef COMPILER2
|
|
#include "opto/c2compiler.hpp"
|
|
#include "opto/idealGraphPrinter.hpp"
|
|
#endif
|
|
|
|
#ifdef DTRACE_ENABLED
|
|
|
|
// Only bother with this argument setup if dtrace is available
|
|
|
|
#ifndef USDT2
|
|
HS_DTRACE_PROBE_DECL(hotspot, vm__init__begin);
|
|
HS_DTRACE_PROBE_DECL(hotspot, vm__init__end);
|
|
HS_DTRACE_PROBE_DECL5(hotspot, thread__start, char*, intptr_t,
|
|
intptr_t, intptr_t, bool);
|
|
HS_DTRACE_PROBE_DECL5(hotspot, thread__stop, char*, intptr_t,
|
|
intptr_t, intptr_t, bool);
|
|
|
|
#define DTRACE_THREAD_PROBE(probe, javathread) \
|
|
{ \
|
|
ResourceMark rm(this); \
|
|
int len = 0; \
|
|
const char* name = (javathread)->get_thread_name(); \
|
|
len = strlen(name); \
|
|
HS_DTRACE_PROBE5(hotspot, thread__##probe, \
|
|
name, len, \
|
|
java_lang_Thread::thread_id((javathread)->threadObj()), \
|
|
(javathread)->osthread()->thread_id(), \
|
|
java_lang_Thread::is_daemon((javathread)->threadObj())); \
|
|
}
|
|
|
|
#else /* USDT2 */
|
|
|
|
#define HOTSPOT_THREAD_PROBE_start HOTSPOT_THREAD_PROBE_START
|
|
#define HOTSPOT_THREAD_PROBE_stop HOTSPOT_THREAD_PROBE_STOP
|
|
|
|
#define DTRACE_THREAD_PROBE(probe, javathread) \
|
|
{ \
|
|
ResourceMark rm(this); \
|
|
int len = 0; \
|
|
const char* name = (javathread)->get_thread_name(); \
|
|
len = strlen(name); \
|
|
HOTSPOT_THREAD_PROBE_##probe( /* probe = start, stop */ \
|
|
(char *) name, len, \
|
|
java_lang_Thread::thread_id((javathread)->threadObj()), \
|
|
(uintptr_t) (javathread)->osthread()->thread_id(), \
|
|
java_lang_Thread::is_daemon((javathread)->threadObj())); \
|
|
}
|
|
|
|
#endif /* USDT2 */
|
|
|
|
#else // ndef DTRACE_ENABLED
|
|
|
|
#define DTRACE_THREAD_PROBE(probe, javathread)
|
|
|
|
#endif // ndef DTRACE_ENABLED
|
|
|
|
|
|
// Class hierarchy
|
|
// - Thread
|
|
// - VMThread
|
|
// - WatcherThread
|
|
// - ConcurrentMarkSweepThread
|
|
// - JavaThread
|
|
// - CompilerThread
|
|
|
|
// ======= Thread ========
|
|
// Support for forcing alignment of thread objects for biased locking
|
|
void* Thread::allocate(size_t size, bool throw_excpt, MEMFLAGS flags) {
|
|
if (UseBiasedLocking) {
|
|
const int alignment = markOopDesc::biased_lock_alignment;
|
|
size_t aligned_size = size + (alignment - sizeof(intptr_t));
|
|
void* real_malloc_addr = throw_excpt? AllocateHeap(aligned_size, flags, CURRENT_PC)
|
|
: AllocateHeap(aligned_size, flags, CURRENT_PC,
|
|
AllocFailStrategy::RETURN_NULL);
|
|
void* aligned_addr = (void*) align_size_up((intptr_t) real_malloc_addr, alignment);
|
|
assert(((uintptr_t) aligned_addr + (uintptr_t) size) <=
|
|
((uintptr_t) real_malloc_addr + (uintptr_t) aligned_size),
|
|
"JavaThread alignment code overflowed allocated storage");
|
|
if (TraceBiasedLocking) {
|
|
if (aligned_addr != real_malloc_addr)
|
|
tty->print_cr("Aligned thread " INTPTR_FORMAT " to " INTPTR_FORMAT,
|
|
real_malloc_addr, aligned_addr);
|
|
}
|
|
((Thread*) aligned_addr)->_real_malloc_address = real_malloc_addr;
|
|
return aligned_addr;
|
|
} else {
|
|
return throw_excpt? AllocateHeap(size, flags, CURRENT_PC)
|
|
: AllocateHeap(size, flags, CURRENT_PC, AllocFailStrategy::RETURN_NULL);
|
|
}
|
|
}
|
|
|
|
void Thread::operator delete(void* p) {
|
|
if (UseBiasedLocking) {
|
|
void* real_malloc_addr = ((Thread*) p)->_real_malloc_address;
|
|
FreeHeap(real_malloc_addr, mtThread);
|
|
} else {
|
|
FreeHeap(p, mtThread);
|
|
}
|
|
}
|
|
|
|
|
|
// Base class for all threads: VMThread, WatcherThread, ConcurrentMarkSweepThread,
|
|
// JavaThread
|
|
|
|
|
|
Thread::Thread() {
|
|
// stack and get_thread
|
|
set_stack_base(NULL);
|
|
set_stack_size(0);
|
|
set_self_raw_id(0);
|
|
set_lgrp_id(-1);
|
|
|
|
// allocated data structures
|
|
set_osthread(NULL);
|
|
set_resource_area(new (mtThread)ResourceArea());
|
|
DEBUG_ONLY(_current_resource_mark = NULL;)
|
|
set_handle_area(new (mtThread) HandleArea(NULL));
|
|
set_metadata_handles(new (ResourceObj::C_HEAP, mtClass) GrowableArray<Metadata*>(30, true));
|
|
set_active_handles(NULL);
|
|
set_free_handle_block(NULL);
|
|
set_last_handle_mark(NULL);
|
|
|
|
// This initial value ==> never claimed.
|
|
_oops_do_parity = 0;
|
|
|
|
// the handle mark links itself to last_handle_mark
|
|
new HandleMark(this);
|
|
|
|
// plain initialization
|
|
debug_only(_owned_locks = NULL;)
|
|
debug_only(_allow_allocation_count = 0;)
|
|
NOT_PRODUCT(_allow_safepoint_count = 0;)
|
|
NOT_PRODUCT(_skip_gcalot = false;)
|
|
CHECK_UNHANDLED_OOPS_ONLY(_gc_locked_out_count = 0;)
|
|
_jvmti_env_iteration_count = 0;
|
|
set_allocated_bytes(0);
|
|
_vm_operation_started_count = 0;
|
|
_vm_operation_completed_count = 0;
|
|
_current_pending_monitor = NULL;
|
|
_current_pending_monitor_is_from_java = true;
|
|
_current_waiting_monitor = NULL;
|
|
_num_nested_signal = 0;
|
|
omFreeList = NULL ;
|
|
omFreeCount = 0 ;
|
|
omFreeProvision = 32 ;
|
|
omInUseList = NULL ;
|
|
omInUseCount = 0 ;
|
|
|
|
#ifdef ASSERT
|
|
_visited_for_critical_count = false;
|
|
#endif
|
|
|
|
_SR_lock = new Monitor(Mutex::suspend_resume, "SR_lock", true);
|
|
_suspend_flags = 0;
|
|
|
|
// thread-specific hashCode stream generator state - Marsaglia shift-xor form
|
|
_hashStateX = os::random() ;
|
|
_hashStateY = 842502087 ;
|
|
_hashStateZ = 0x8767 ; // (int)(3579807591LL & 0xffff) ;
|
|
_hashStateW = 273326509 ;
|
|
|
|
_OnTrap = 0 ;
|
|
_schedctl = NULL ;
|
|
_Stalled = 0 ;
|
|
_TypeTag = 0x2BAD ;
|
|
|
|
// Many of the following fields are effectively final - immutable
|
|
// Note that nascent threads can't use the Native Monitor-Mutex
|
|
// construct until the _MutexEvent is initialized ...
|
|
// CONSIDER: instead of using a fixed set of purpose-dedicated ParkEvents
|
|
// we might instead use a stack of ParkEvents that we could provision on-demand.
|
|
// The stack would act as a cache to avoid calls to ParkEvent::Allocate()
|
|
// and ::Release()
|
|
_ParkEvent = ParkEvent::Allocate (this) ;
|
|
_SleepEvent = ParkEvent::Allocate (this) ;
|
|
_MutexEvent = ParkEvent::Allocate (this) ;
|
|
_MuxEvent = ParkEvent::Allocate (this) ;
|
|
|
|
#ifdef CHECK_UNHANDLED_OOPS
|
|
if (CheckUnhandledOops) {
|
|
_unhandled_oops = new UnhandledOops(this);
|
|
}
|
|
#endif // CHECK_UNHANDLED_OOPS
|
|
#ifdef ASSERT
|
|
if (UseBiasedLocking) {
|
|
assert((((uintptr_t) this) & (markOopDesc::biased_lock_alignment - 1)) == 0, "forced alignment of thread object failed");
|
|
assert(this == _real_malloc_address ||
|
|
this == (void*) align_size_up((intptr_t) _real_malloc_address, markOopDesc::biased_lock_alignment),
|
|
"bug in forced alignment of thread objects");
|
|
}
|
|
#endif /* ASSERT */
|
|
}
|
|
|
|
void Thread::initialize_thread_local_storage() {
|
|
// Note: Make sure this method only calls
|
|
// non-blocking operations. Otherwise, it might not work
|
|
// with the thread-startup/safepoint interaction.
|
|
|
|
// During Java thread startup, safepoint code should allow this
|
|
// method to complete because it may need to allocate memory to
|
|
// store information for the new thread.
|
|
|
|
// initialize structure dependent on thread local storage
|
|
ThreadLocalStorage::set_thread(this);
|
|
}
|
|
|
|
void Thread::record_stack_base_and_size() {
|
|
set_stack_base(os::current_stack_base());
|
|
set_stack_size(os::current_stack_size());
|
|
// CR 7190089: on Solaris, primordial thread's stack is adjusted
|
|
// in initialize_thread(). Without the adjustment, stack size is
|
|
// incorrect if stack is set to unlimited (ulimit -s unlimited).
|
|
// So far, only Solaris has real implementation of initialize_thread().
|
|
//
|
|
// set up any platform-specific state.
|
|
os::initialize_thread(this);
|
|
|
|
#if INCLUDE_NMT
|
|
// record thread's native stack, stack grows downward
|
|
address stack_low_addr = stack_base() - stack_size();
|
|
MemTracker::record_thread_stack(stack_low_addr, stack_size(), this,
|
|
CURRENT_PC);
|
|
#endif // INCLUDE_NMT
|
|
}
|
|
|
|
|
|
Thread::~Thread() {
|
|
// Reclaim the objectmonitors from the omFreeList of the moribund thread.
|
|
ObjectSynchronizer::omFlush (this) ;
|
|
|
|
EVENT_THREAD_DESTRUCT(this);
|
|
|
|
// stack_base can be NULL if the thread is never started or exited before
|
|
// record_stack_base_and_size called. Although, we would like to ensure
|
|
// that all started threads do call record_stack_base_and_size(), there is
|
|
// not proper way to enforce that.
|
|
#if INCLUDE_NMT
|
|
if (_stack_base != NULL) {
|
|
address low_stack_addr = stack_base() - stack_size();
|
|
MemTracker::release_thread_stack(low_stack_addr, stack_size(), this);
|
|
#ifdef ASSERT
|
|
set_stack_base(NULL);
|
|
#endif
|
|
}
|
|
#endif // INCLUDE_NMT
|
|
|
|
// deallocate data structures
|
|
delete resource_area();
|
|
// since the handle marks are using the handle area, we have to deallocated the root
|
|
// handle mark before deallocating the thread's handle area,
|
|
assert(last_handle_mark() != NULL, "check we have an element");
|
|
delete last_handle_mark();
|
|
assert(last_handle_mark() == NULL, "check we have reached the end");
|
|
|
|
// It's possible we can encounter a null _ParkEvent, etc., in stillborn threads.
|
|
// We NULL out the fields for good hygiene.
|
|
ParkEvent::Release (_ParkEvent) ; _ParkEvent = NULL ;
|
|
ParkEvent::Release (_SleepEvent) ; _SleepEvent = NULL ;
|
|
ParkEvent::Release (_MutexEvent) ; _MutexEvent = NULL ;
|
|
ParkEvent::Release (_MuxEvent) ; _MuxEvent = NULL ;
|
|
|
|
delete handle_area();
|
|
delete metadata_handles();
|
|
|
|
// osthread() can be NULL, if creation of thread failed.
|
|
if (osthread() != NULL) os::free_thread(osthread());
|
|
|
|
delete _SR_lock;
|
|
|
|
// clear thread local storage if the Thread is deleting itself
|
|
if (this == Thread::current()) {
|
|
ThreadLocalStorage::set_thread(NULL);
|
|
} else {
|
|
// In the case where we're not the current thread, invalidate all the
|
|
// caches in case some code tries to get the current thread or the
|
|
// thread that was destroyed, and gets stale information.
|
|
ThreadLocalStorage::invalidate_all();
|
|
}
|
|
CHECK_UNHANDLED_OOPS_ONLY(if (CheckUnhandledOops) delete unhandled_oops();)
|
|
}
|
|
|
|
// NOTE: dummy function for assertion purpose.
|
|
void Thread::run() {
|
|
ShouldNotReachHere();
|
|
}
|
|
|
|
#ifdef ASSERT
|
|
// Private method to check for dangling thread pointer
|
|
void check_for_dangling_thread_pointer(Thread *thread) {
|
|
assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
|
|
"possibility of dangling Thread pointer");
|
|
}
|
|
#endif
|
|
|
|
|
|
#ifndef PRODUCT
|
|
// Tracing method for basic thread operations
|
|
void Thread::trace(const char* msg, const Thread* const thread) {
|
|
if (!TraceThreadEvents) return;
|
|
ResourceMark rm;
|
|
ThreadCritical tc;
|
|
const char *name = "non-Java thread";
|
|
int prio = -1;
|
|
if (thread->is_Java_thread()
|
|
&& !thread->is_Compiler_thread()) {
|
|
// The Threads_lock must be held to get information about
|
|
// this thread but may not be in some situations when
|
|
// tracing thread events.
|
|
bool release_Threads_lock = false;
|
|
if (!Threads_lock->owned_by_self()) {
|
|
Threads_lock->lock();
|
|
release_Threads_lock = true;
|
|
}
|
|
JavaThread* jt = (JavaThread *)thread;
|
|
name = (char *)jt->get_thread_name();
|
|
oop thread_oop = jt->threadObj();
|
|
if (thread_oop != NULL) {
|
|
prio = java_lang_Thread::priority(thread_oop);
|
|
}
|
|
if (release_Threads_lock) {
|
|
Threads_lock->unlock();
|
|
}
|
|
}
|
|
tty->print_cr("Thread::%s " INTPTR_FORMAT " [%lx] %s (prio: %d)", msg, thread, thread->osthread()->thread_id(), name, prio);
|
|
}
|
|
#endif
|
|
|
|
|
|
ThreadPriority Thread::get_priority(const Thread* const thread) {
|
|
trace("get priority", thread);
|
|
ThreadPriority priority;
|
|
// Can return an error!
|
|
(void)os::get_priority(thread, priority);
|
|
assert(MinPriority <= priority && priority <= MaxPriority, "non-Java priority found");
|
|
return priority;
|
|
}
|
|
|
|
void Thread::set_priority(Thread* thread, ThreadPriority priority) {
|
|
trace("set priority", thread);
|
|
debug_only(check_for_dangling_thread_pointer(thread);)
|
|
// Can return an error!
|
|
(void)os::set_priority(thread, priority);
|
|
}
|
|
|
|
|
|
void Thread::start(Thread* thread) {
|
|
trace("start", thread);
|
|
// Start is different from resume in that its safety is guaranteed by context or
|
|
// being called from a Java method synchronized on the Thread object.
|
|
if (!DisableStartThread) {
|
|
if (thread->is_Java_thread()) {
|
|
// Initialize the thread state to RUNNABLE before starting this thread.
|
|
// Can not set it after the thread started because we do not know the
|
|
// exact thread state at that time. It could be in MONITOR_WAIT or
|
|
// in SLEEPING or some other state.
|
|
java_lang_Thread::set_thread_status(((JavaThread*)thread)->threadObj(),
|
|
java_lang_Thread::RUNNABLE);
|
|
}
|
|
os::start_thread(thread);
|
|
}
|
|
}
|
|
|
|
// Enqueue a VM_Operation to do the job for us - sometime later
|
|
void Thread::send_async_exception(oop java_thread, oop java_throwable) {
|
|
VM_ThreadStop* vm_stop = new VM_ThreadStop(java_thread, java_throwable);
|
|
VMThread::execute(vm_stop);
|
|
}
|
|
|
|
|
|
//
|
|
// Check if an external suspend request has completed (or has been
|
|
// cancelled). Returns true if the thread is externally suspended and
|
|
// false otherwise.
|
|
//
|
|
// The bits parameter returns information about the code path through
|
|
// the routine. Useful for debugging:
|
|
//
|
|
// set in is_ext_suspend_completed():
|
|
// 0x00000001 - routine was entered
|
|
// 0x00000010 - routine return false at end
|
|
// 0x00000100 - thread exited (return false)
|
|
// 0x00000200 - suspend request cancelled (return false)
|
|
// 0x00000400 - thread suspended (return true)
|
|
// 0x00001000 - thread is in a suspend equivalent state (return true)
|
|
// 0x00002000 - thread is native and walkable (return true)
|
|
// 0x00004000 - thread is native_trans and walkable (needed retry)
|
|
//
|
|
// set in wait_for_ext_suspend_completion():
|
|
// 0x00010000 - routine was entered
|
|
// 0x00020000 - suspend request cancelled before loop (return false)
|
|
// 0x00040000 - thread suspended before loop (return true)
|
|
// 0x00080000 - suspend request cancelled in loop (return false)
|
|
// 0x00100000 - thread suspended in loop (return true)
|
|
// 0x00200000 - suspend not completed during retry loop (return false)
|
|
//
|
|
|
|
// Helper class for tracing suspend wait debug bits.
|
|
//
|
|
// 0x00000100 indicates that the target thread exited before it could
|
|
// self-suspend which is not a wait failure. 0x00000200, 0x00020000 and
|
|
// 0x00080000 each indicate a cancelled suspend request so they don't
|
|
// count as wait failures either.
|
|
#define DEBUG_FALSE_BITS (0x00000010 | 0x00200000)
|
|
|
|
class TraceSuspendDebugBits : public StackObj {
|
|
private:
|
|
JavaThread * jt;
|
|
bool is_wait;
|
|
bool called_by_wait; // meaningful when !is_wait
|
|
uint32_t * bits;
|
|
|
|
public:
|
|
TraceSuspendDebugBits(JavaThread *_jt, bool _is_wait, bool _called_by_wait,
|
|
uint32_t *_bits) {
|
|
jt = _jt;
|
|
is_wait = _is_wait;
|
|
called_by_wait = _called_by_wait;
|
|
bits = _bits;
|
|
}
|
|
|
|
~TraceSuspendDebugBits() {
|
|
if (!is_wait) {
|
|
#if 1
|
|
// By default, don't trace bits for is_ext_suspend_completed() calls.
|
|
// That trace is very chatty.
|
|
return;
|
|
#else
|
|
if (!called_by_wait) {
|
|
// If tracing for is_ext_suspend_completed() is enabled, then only
|
|
// trace calls to it from wait_for_ext_suspend_completion()
|
|
return;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if (AssertOnSuspendWaitFailure || TraceSuspendWaitFailures) {
|
|
if (bits != NULL && (*bits & DEBUG_FALSE_BITS) != 0) {
|
|
MutexLocker ml(Threads_lock); // needed for get_thread_name()
|
|
ResourceMark rm;
|
|
|
|
tty->print_cr(
|
|
"Failed wait_for_ext_suspend_completion(thread=%s, debug_bits=%x)",
|
|
jt->get_thread_name(), *bits);
|
|
|
|
guarantee(!AssertOnSuspendWaitFailure, "external suspend wait failed");
|
|
}
|
|
}
|
|
}
|
|
};
|
|
#undef DEBUG_FALSE_BITS
|
|
|
|
|
|
bool JavaThread::is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits) {
|
|
TraceSuspendDebugBits tsdb(this, false /* !is_wait */, called_by_wait, bits);
|
|
|
|
bool did_trans_retry = false; // only do thread_in_native_trans retry once
|
|
bool do_trans_retry; // flag to force the retry
|
|
|
|
*bits |= 0x00000001;
|
|
|
|
do {
|
|
do_trans_retry = false;
|
|
|
|
if (is_exiting()) {
|
|
// Thread is in the process of exiting. This is always checked
|
|
// first to reduce the risk of dereferencing a freed JavaThread.
|
|
*bits |= 0x00000100;
|
|
return false;
|
|
}
|
|
|
|
if (!is_external_suspend()) {
|
|
// Suspend request is cancelled. This is always checked before
|
|
// is_ext_suspended() to reduce the risk of a rogue resume
|
|
// confusing the thread that made the suspend request.
|
|
*bits |= 0x00000200;
|
|
return false;
|
|
}
|
|
|
|
if (is_ext_suspended()) {
|
|
// thread is suspended
|
|
*bits |= 0x00000400;
|
|
return true;
|
|
}
|
|
|
|
// Now that we no longer do hard suspends of threads running
|
|
// native code, the target thread can be changing thread state
|
|
// while we are in this routine:
|
|
//
|
|
// _thread_in_native -> _thread_in_native_trans -> _thread_blocked
|
|
//
|
|
// We save a copy of the thread state as observed at this moment
|
|
// and make our decision about suspend completeness based on the
|
|
// copy. This closes the race where the thread state is seen as
|
|
// _thread_in_native_trans in the if-thread_blocked check, but is
|
|
// seen as _thread_blocked in if-thread_in_native_trans check.
|
|
JavaThreadState save_state = thread_state();
|
|
|
|
if (save_state == _thread_blocked && is_suspend_equivalent()) {
|
|
// If the thread's state is _thread_blocked and this blocking
|
|
// condition is known to be equivalent to a suspend, then we can
|
|
// consider the thread to be externally suspended. This means that
|
|
// the code that sets _thread_blocked has been modified to do
|
|
// self-suspension if the blocking condition releases. We also
|
|
// used to check for CONDVAR_WAIT here, but that is now covered by
|
|
// the _thread_blocked with self-suspension check.
|
|
//
|
|
// Return true since we wouldn't be here unless there was still an
|
|
// external suspend request.
|
|
*bits |= 0x00001000;
|
|
return true;
|
|
} else if (save_state == _thread_in_native && frame_anchor()->walkable()) {
|
|
// Threads running native code will self-suspend on native==>VM/Java
|
|
// transitions. If its stack is walkable (should always be the case
|
|
// unless this function is called before the actual java_suspend()
|
|
// call), then the wait is done.
|
|
*bits |= 0x00002000;
|
|
return true;
|
|
} else if (!called_by_wait && !did_trans_retry &&
|
|
save_state == _thread_in_native_trans &&
|
|
frame_anchor()->walkable()) {
|
|
// The thread is transitioning from thread_in_native to another
|
|
// thread state. check_safepoint_and_suspend_for_native_trans()
|
|
// will force the thread to self-suspend. If it hasn't gotten
|
|
// there yet we may have caught the thread in-between the native
|
|
// code check above and the self-suspend. Lucky us. If we were
|
|
// called by wait_for_ext_suspend_completion(), then it
|
|
// will be doing the retries so we don't have to.
|
|
//
|
|
// Since we use the saved thread state in the if-statement above,
|
|
// there is a chance that the thread has already transitioned to
|
|
// _thread_blocked by the time we get here. In that case, we will
|
|
// make a single unnecessary pass through the logic below. This
|
|
// doesn't hurt anything since we still do the trans retry.
|
|
|
|
*bits |= 0x00004000;
|
|
|
|
// Once the thread leaves thread_in_native_trans for another
|
|
// thread state, we break out of this retry loop. We shouldn't
|
|
// need this flag to prevent us from getting back here, but
|
|
// sometimes paranoia is good.
|
|
did_trans_retry = true;
|
|
|
|
// We wait for the thread to transition to a more usable state.
|
|
for (int i = 1; i <= SuspendRetryCount; i++) {
|
|
// We used to do an "os::yield_all(i)" call here with the intention
|
|
// that yielding would increase on each retry. However, the parameter
|
|
// is ignored on Linux which means the yield didn't scale up. Waiting
|
|
// on the SR_lock below provides a much more predictable scale up for
|
|
// the delay. It also provides a simple/direct point to check for any
|
|
// safepoint requests from the VMThread
|
|
|
|
// temporarily drops SR_lock while doing wait with safepoint check
|
|
// (if we're a JavaThread - the WatcherThread can also call this)
|
|
// and increase delay with each retry
|
|
SR_lock()->wait(!Thread::current()->is_Java_thread(), i * delay);
|
|
|
|
// check the actual thread state instead of what we saved above
|
|
if (thread_state() != _thread_in_native_trans) {
|
|
// the thread has transitioned to another thread state so
|
|
// try all the checks (except this one) one more time.
|
|
do_trans_retry = true;
|
|
break;
|
|
}
|
|
} // end retry loop
|
|
|
|
|
|
}
|
|
} while (do_trans_retry);
|
|
|
|
*bits |= 0x00000010;
|
|
return false;
|
|
}
|
|
|
|
//
|
|
// Wait for an external suspend request to complete (or be cancelled).
|
|
// Returns true if the thread is externally suspended and false otherwise.
|
|
//
|
|
bool JavaThread::wait_for_ext_suspend_completion(int retries, int delay,
|
|
uint32_t *bits) {
|
|
TraceSuspendDebugBits tsdb(this, true /* is_wait */,
|
|
false /* !called_by_wait */, bits);
|
|
|
|
// local flag copies to minimize SR_lock hold time
|
|
bool is_suspended;
|
|
bool pending;
|
|
uint32_t reset_bits;
|
|
|
|
// set a marker so is_ext_suspend_completed() knows we are the caller
|
|
*bits |= 0x00010000;
|
|
|
|
// We use reset_bits to reinitialize the bits value at the top of
|
|
// each retry loop. This allows the caller to make use of any
|
|
// unused bits for their own marking purposes.
|
|
reset_bits = *bits;
|
|
|
|
{
|
|
MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
is_suspended = is_ext_suspend_completed(true /* called_by_wait */,
|
|
delay, bits);
|
|
pending = is_external_suspend();
|
|
}
|
|
// must release SR_lock to allow suspension to complete
|
|
|
|
if (!pending) {
|
|
// A cancelled suspend request is the only false return from
|
|
// is_ext_suspend_completed() that keeps us from entering the
|
|
// retry loop.
|
|
*bits |= 0x00020000;
|
|
return false;
|
|
}
|
|
|
|
if (is_suspended) {
|
|
*bits |= 0x00040000;
|
|
return true;
|
|
}
|
|
|
|
for (int i = 1; i <= retries; i++) {
|
|
*bits = reset_bits; // reinit to only track last retry
|
|
|
|
// We used to do an "os::yield_all(i)" call here with the intention
|
|
// that yielding would increase on each retry. However, the parameter
|
|
// is ignored on Linux which means the yield didn't scale up. Waiting
|
|
// on the SR_lock below provides a much more predictable scale up for
|
|
// the delay. It also provides a simple/direct point to check for any
|
|
// safepoint requests from the VMThread
|
|
|
|
{
|
|
MutexLocker ml(SR_lock());
|
|
// wait with safepoint check (if we're a JavaThread - the WatcherThread
|
|
// can also call this) and increase delay with each retry
|
|
SR_lock()->wait(!Thread::current()->is_Java_thread(), i * delay);
|
|
|
|
is_suspended = is_ext_suspend_completed(true /* called_by_wait */,
|
|
delay, bits);
|
|
|
|
// It is possible for the external suspend request to be cancelled
|
|
// (by a resume) before the actual suspend operation is completed.
|
|
// Refresh our local copy to see if we still need to wait.
|
|
pending = is_external_suspend();
|
|
}
|
|
|
|
if (!pending) {
|
|
// A cancelled suspend request is the only false return from
|
|
// is_ext_suspend_completed() that keeps us from staying in the
|
|
// retry loop.
|
|
*bits |= 0x00080000;
|
|
return false;
|
|
}
|
|
|
|
if (is_suspended) {
|
|
*bits |= 0x00100000;
|
|
return true;
|
|
}
|
|
} // end retry loop
|
|
|
|
// thread did not suspend after all our retries
|
|
*bits |= 0x00200000;
|
|
return false;
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
void JavaThread::record_jump(address target, address instr, const char* file, int line) {
|
|
|
|
// This should not need to be atomic as the only way for simultaneous
|
|
// updates is via interrupts. Even then this should be rare or non-existant
|
|
// and we don't care that much anyway.
|
|
|
|
int index = _jmp_ring_index;
|
|
_jmp_ring_index = (index + 1 ) & (jump_ring_buffer_size - 1);
|
|
_jmp_ring[index]._target = (intptr_t) target;
|
|
_jmp_ring[index]._instruction = (intptr_t) instr;
|
|
_jmp_ring[index]._file = file;
|
|
_jmp_ring[index]._line = line;
|
|
}
|
|
#endif /* PRODUCT */
|
|
|
|
// Called by flat profiler
|
|
// Callers have already called wait_for_ext_suspend_completion
|
|
// The assertion for that is currently too complex to put here:
|
|
bool JavaThread::profile_last_Java_frame(frame* _fr) {
|
|
bool gotframe = false;
|
|
// self suspension saves needed state.
|
|
if (has_last_Java_frame() && _anchor.walkable()) {
|
|
*_fr = pd_last_frame();
|
|
gotframe = true;
|
|
}
|
|
return gotframe;
|
|
}
|
|
|
|
void Thread::interrupt(Thread* thread) {
|
|
trace("interrupt", thread);
|
|
debug_only(check_for_dangling_thread_pointer(thread);)
|
|
os::interrupt(thread);
|
|
}
|
|
|
|
bool Thread::is_interrupted(Thread* thread, bool clear_interrupted) {
|
|
trace("is_interrupted", thread);
|
|
debug_only(check_for_dangling_thread_pointer(thread);)
|
|
// Note: If clear_interrupted==false, this simply fetches and
|
|
// returns the value of the field osthread()->interrupted().
|
|
return os::is_interrupted(thread, clear_interrupted);
|
|
}
|
|
|
|
|
|
// GC Support
|
|
bool Thread::claim_oops_do_par_case(int strong_roots_parity) {
|
|
jint thread_parity = _oops_do_parity;
|
|
if (thread_parity != strong_roots_parity) {
|
|
jint res = Atomic::cmpxchg(strong_roots_parity, &_oops_do_parity, thread_parity);
|
|
if (res == thread_parity) {
|
|
return true;
|
|
} else {
|
|
guarantee(res == strong_roots_parity, "Or else what?");
|
|
assert(SharedHeap::heap()->workers()->active_workers() > 0,
|
|
"Should only fail when parallel.");
|
|
return false;
|
|
}
|
|
}
|
|
assert(SharedHeap::heap()->workers()->active_workers() > 0,
|
|
"Should only fail when parallel.");
|
|
return false;
|
|
}
|
|
|
|
void Thread::oops_do(OopClosure* f, CLDToOopClosure* cld_f, CodeBlobClosure* cf) {
|
|
active_handles()->oops_do(f);
|
|
// Do oop for ThreadShadow
|
|
f->do_oop((oop*)&_pending_exception);
|
|
handle_area()->oops_do(f);
|
|
}
|
|
|
|
void Thread::nmethods_do(CodeBlobClosure* cf) {
|
|
// no nmethods in a generic thread...
|
|
}
|
|
|
|
void Thread::metadata_do(void f(Metadata*)) {
|
|
if (metadata_handles() != NULL) {
|
|
for (int i = 0; i< metadata_handles()->length(); i++) {
|
|
f(metadata_handles()->at(i));
|
|
}
|
|
}
|
|
}
|
|
|
|
void Thread::print_on(outputStream* st) const {
|
|
// get_priority assumes osthread initialized
|
|
if (osthread() != NULL) {
|
|
int os_prio;
|
|
if (os::get_native_priority(this, &os_prio) == OS_OK) {
|
|
st->print("os_prio=%d ", os_prio);
|
|
}
|
|
st->print("tid=" INTPTR_FORMAT " ", this);
|
|
osthread()->print_on(st);
|
|
}
|
|
debug_only(if (WizardMode) print_owned_locks_on(st);)
|
|
}
|
|
|
|
// Thread::print_on_error() is called by fatal error handler. Don't use
|
|
// any lock or allocate memory.
|
|
void Thread::print_on_error(outputStream* st, char* buf, int buflen) const {
|
|
if (is_VM_thread()) st->print("VMThread");
|
|
else if (is_Compiler_thread()) st->print("CompilerThread");
|
|
else if (is_Java_thread()) st->print("JavaThread");
|
|
else if (is_GC_task_thread()) st->print("GCTaskThread");
|
|
else if (is_Watcher_thread()) st->print("WatcherThread");
|
|
else if (is_ConcurrentGC_thread()) st->print("ConcurrentGCThread");
|
|
else st->print("Thread");
|
|
|
|
st->print(" [stack: " PTR_FORMAT "," PTR_FORMAT "]",
|
|
_stack_base - _stack_size, _stack_base);
|
|
|
|
if (osthread()) {
|
|
st->print(" [id=%d]", osthread()->thread_id());
|
|
}
|
|
}
|
|
|
|
#ifdef ASSERT
|
|
void Thread::print_owned_locks_on(outputStream* st) const {
|
|
Monitor *cur = _owned_locks;
|
|
if (cur == NULL) {
|
|
st->print(" (no locks) ");
|
|
} else {
|
|
st->print_cr(" Locks owned:");
|
|
while(cur) {
|
|
cur->print_on(st);
|
|
cur = cur->next();
|
|
}
|
|
}
|
|
}
|
|
|
|
static int ref_use_count = 0;
|
|
|
|
bool Thread::owns_locks_but_compiled_lock() const {
|
|
for(Monitor *cur = _owned_locks; cur; cur = cur->next()) {
|
|
if (cur != Compile_lock) return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
#endif
|
|
|
|
#ifndef PRODUCT
|
|
|
|
// The flag: potential_vm_operation notifies if this particular safepoint state could potential
|
|
// invoke the vm-thread (i.e., and oop allocation). In that case, we also have to make sure that
|
|
// no threads which allow_vm_block's are held
|
|
void Thread::check_for_valid_safepoint_state(bool potential_vm_operation) {
|
|
// Check if current thread is allowed to block at a safepoint
|
|
if (!(_allow_safepoint_count == 0))
|
|
fatal("Possible safepoint reached by thread that does not allow it");
|
|
if (is_Java_thread() && ((JavaThread*)this)->thread_state() != _thread_in_vm) {
|
|
fatal("LEAF method calling lock?");
|
|
}
|
|
|
|
#ifdef ASSERT
|
|
if (potential_vm_operation && is_Java_thread()
|
|
&& !Universe::is_bootstrapping()) {
|
|
// Make sure we do not hold any locks that the VM thread also uses.
|
|
// This could potentially lead to deadlocks
|
|
for(Monitor *cur = _owned_locks; cur; cur = cur->next()) {
|
|
// Threads_lock is special, since the safepoint synchronization will not start before this is
|
|
// acquired. Hence, a JavaThread cannot be holding it at a safepoint. So is VMOperationRequest_lock,
|
|
// since it is used to transfer control between JavaThreads and the VMThread
|
|
// Do not *exclude* any locks unless you are absolutly sure it is correct. Ask someone else first!
|
|
if ( (cur->allow_vm_block() &&
|
|
cur != Threads_lock &&
|
|
cur != Compile_lock && // Temporary: should not be necessary when we get spearate compilation
|
|
cur != VMOperationRequest_lock &&
|
|
cur != VMOperationQueue_lock) ||
|
|
cur->rank() == Mutex::special) {
|
|
warning("Thread holding lock at safepoint that vm can block on: %s", cur->name());
|
|
}
|
|
}
|
|
}
|
|
|
|
if (GCALotAtAllSafepoints) {
|
|
// We could enter a safepoint here and thus have a gc
|
|
InterfaceSupport::check_gc_alot();
|
|
}
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
bool Thread::is_in_stack(address adr) const {
|
|
assert(Thread::current() == this, "is_in_stack can only be called from current thread");
|
|
address end = os::current_stack_pointer();
|
|
// Allow non Java threads to call this without stack_base
|
|
if (_stack_base == NULL) return true;
|
|
if (stack_base() >= adr && adr >= end) return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
bool Thread::is_in_usable_stack(address adr) const {
|
|
size_t stack_guard_size = os::uses_stack_guard_pages() ? (StackYellowPages + StackRedPages) * os::vm_page_size() : 0;
|
|
size_t usable_stack_size = _stack_size - stack_guard_size;
|
|
|
|
return ((adr < stack_base()) && (adr >= stack_base() - usable_stack_size));
|
|
}
|
|
|
|
|
|
// We had to move these methods here, because vm threads get into ObjectSynchronizer::enter
|
|
// However, there is a note in JavaThread::is_lock_owned() about the VM threads not being
|
|
// used for compilation in the future. If that change is made, the need for these methods
|
|
// should be revisited, and they should be removed if possible.
|
|
|
|
bool Thread::is_lock_owned(address adr) const {
|
|
return on_local_stack(adr);
|
|
}
|
|
|
|
bool Thread::set_as_starting_thread() {
|
|
// NOTE: this must be called inside the main thread.
|
|
return os::create_main_thread((JavaThread*)this);
|
|
}
|
|
|
|
static void initialize_class(Symbol* class_name, TRAPS) {
|
|
Klass* klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK);
|
|
InstanceKlass::cast(klass)->initialize(CHECK);
|
|
}
|
|
|
|
|
|
// Creates the initial ThreadGroup
|
|
static Handle create_initial_thread_group(TRAPS) {
|
|
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ThreadGroup(), true, CHECK_NH);
|
|
instanceKlassHandle klass (THREAD, k);
|
|
|
|
Handle system_instance = klass->allocate_instance_handle(CHECK_NH);
|
|
{
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_special(&result,
|
|
system_instance,
|
|
klass,
|
|
vmSymbols::object_initializer_name(),
|
|
vmSymbols::void_method_signature(),
|
|
CHECK_NH);
|
|
}
|
|
Universe::set_system_thread_group(system_instance());
|
|
|
|
Handle main_instance = klass->allocate_instance_handle(CHECK_NH);
|
|
{
|
|
JavaValue result(T_VOID);
|
|
Handle string = java_lang_String::create_from_str("main", CHECK_NH);
|
|
JavaCalls::call_special(&result,
|
|
main_instance,
|
|
klass,
|
|
vmSymbols::object_initializer_name(),
|
|
vmSymbols::threadgroup_string_void_signature(),
|
|
system_instance,
|
|
string,
|
|
CHECK_NH);
|
|
}
|
|
return main_instance;
|
|
}
|
|
|
|
// Creates the initial Thread
|
|
static oop create_initial_thread(Handle thread_group, JavaThread* thread, TRAPS) {
|
|
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK_NULL);
|
|
instanceKlassHandle klass (THREAD, k);
|
|
instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_NULL);
|
|
|
|
java_lang_Thread::set_thread(thread_oop(), thread);
|
|
java_lang_Thread::set_priority(thread_oop(), NormPriority);
|
|
thread->set_threadObj(thread_oop());
|
|
|
|
Handle string = java_lang_String::create_from_str("main", CHECK_NULL);
|
|
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_special(&result, thread_oop,
|
|
klass,
|
|
vmSymbols::object_initializer_name(),
|
|
vmSymbols::threadgroup_string_void_signature(),
|
|
thread_group,
|
|
string,
|
|
CHECK_NULL);
|
|
return thread_oop();
|
|
}
|
|
|
|
static void call_initializeSystemClass(TRAPS) {
|
|
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_System(), true, CHECK);
|
|
instanceKlassHandle klass (THREAD, k);
|
|
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_static(&result, klass, vmSymbols::initializeSystemClass_name(),
|
|
vmSymbols::void_method_signature(), CHECK);
|
|
}
|
|
|
|
char java_runtime_name[128] = "";
|
|
char java_runtime_version[128] = "";
|
|
|
|
// extract the JRE name from sun.misc.Version.java_runtime_name
|
|
static const char* get_java_runtime_name(TRAPS) {
|
|
Klass* k = SystemDictionary::find(vmSymbols::sun_misc_Version(),
|
|
Handle(), Handle(), CHECK_AND_CLEAR_NULL);
|
|
fieldDescriptor fd;
|
|
bool found = k != NULL &&
|
|
InstanceKlass::cast(k)->find_local_field(vmSymbols::java_runtime_name_name(),
|
|
vmSymbols::string_signature(), &fd);
|
|
if (found) {
|
|
oop name_oop = k->java_mirror()->obj_field(fd.offset());
|
|
if (name_oop == NULL)
|
|
return NULL;
|
|
const char* name = java_lang_String::as_utf8_string(name_oop,
|
|
java_runtime_name,
|
|
sizeof(java_runtime_name));
|
|
return name;
|
|
} else {
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
// extract the JRE version from sun.misc.Version.java_runtime_version
|
|
static const char* get_java_runtime_version(TRAPS) {
|
|
Klass* k = SystemDictionary::find(vmSymbols::sun_misc_Version(),
|
|
Handle(), Handle(), CHECK_AND_CLEAR_NULL);
|
|
fieldDescriptor fd;
|
|
bool found = k != NULL &&
|
|
InstanceKlass::cast(k)->find_local_field(vmSymbols::java_runtime_version_name(),
|
|
vmSymbols::string_signature(), &fd);
|
|
if (found) {
|
|
oop name_oop = k->java_mirror()->obj_field(fd.offset());
|
|
if (name_oop == NULL)
|
|
return NULL;
|
|
const char* name = java_lang_String::as_utf8_string(name_oop,
|
|
java_runtime_version,
|
|
sizeof(java_runtime_version));
|
|
return name;
|
|
} else {
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
// General purpose hook into Java code, run once when the VM is initialized.
|
|
// The Java library method itself may be changed independently from the VM.
|
|
static void call_postVMInitHook(TRAPS) {
|
|
Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_PostVMInitHook(), THREAD);
|
|
instanceKlassHandle klass (THREAD, k);
|
|
if (klass.not_null()) {
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(),
|
|
vmSymbols::void_method_signature(),
|
|
CHECK);
|
|
}
|
|
}
|
|
|
|
static void reset_vm_info_property(TRAPS) {
|
|
// the vm info string
|
|
ResourceMark rm(THREAD);
|
|
const char *vm_info = VM_Version::vm_info_string();
|
|
|
|
// java.lang.System class
|
|
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_System(), true, CHECK);
|
|
instanceKlassHandle klass (THREAD, k);
|
|
|
|
// setProperty arguments
|
|
Handle key_str = java_lang_String::create_from_str("java.vm.info", CHECK);
|
|
Handle value_str = java_lang_String::create_from_str(vm_info, CHECK);
|
|
|
|
// return value
|
|
JavaValue r(T_OBJECT);
|
|
|
|
// public static String setProperty(String key, String value);
|
|
JavaCalls::call_static(&r,
|
|
klass,
|
|
vmSymbols::setProperty_name(),
|
|
vmSymbols::string_string_string_signature(),
|
|
key_str,
|
|
value_str,
|
|
CHECK);
|
|
}
|
|
|
|
|
|
void JavaThread::allocate_threadObj(Handle thread_group, char* thread_name, bool daemon, TRAPS) {
|
|
assert(thread_group.not_null(), "thread group should be specified");
|
|
assert(threadObj() == NULL, "should only create Java thread object once");
|
|
|
|
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
|
|
instanceKlassHandle klass (THREAD, k);
|
|
instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
|
|
|
|
java_lang_Thread::set_thread(thread_oop(), this);
|
|
java_lang_Thread::set_priority(thread_oop(), NormPriority);
|
|
set_threadObj(thread_oop());
|
|
|
|
JavaValue result(T_VOID);
|
|
if (thread_name != NULL) {
|
|
Handle name = java_lang_String::create_from_str(thread_name, CHECK);
|
|
// Thread gets assigned specified name and null target
|
|
JavaCalls::call_special(&result,
|
|
thread_oop,
|
|
klass,
|
|
vmSymbols::object_initializer_name(),
|
|
vmSymbols::threadgroup_string_void_signature(),
|
|
thread_group, // Argument 1
|
|
name, // Argument 2
|
|
THREAD);
|
|
} else {
|
|
// Thread gets assigned name "Thread-nnn" and null target
|
|
// (java.lang.Thread doesn't have a constructor taking only a ThreadGroup argument)
|
|
JavaCalls::call_special(&result,
|
|
thread_oop,
|
|
klass,
|
|
vmSymbols::object_initializer_name(),
|
|
vmSymbols::threadgroup_runnable_void_signature(),
|
|
thread_group, // Argument 1
|
|
Handle(), // Argument 2
|
|
THREAD);
|
|
}
|
|
|
|
|
|
if (daemon) {
|
|
java_lang_Thread::set_daemon(thread_oop());
|
|
}
|
|
|
|
if (HAS_PENDING_EXCEPTION) {
|
|
return;
|
|
}
|
|
|
|
KlassHandle group(this, SystemDictionary::ThreadGroup_klass());
|
|
Handle threadObj(this, this->threadObj());
|
|
|
|
JavaCalls::call_special(&result,
|
|
thread_group,
|
|
group,
|
|
vmSymbols::add_method_name(),
|
|
vmSymbols::thread_void_signature(),
|
|
threadObj, // Arg 1
|
|
THREAD);
|
|
|
|
|
|
}
|
|
|
|
// NamedThread -- non-JavaThread subclasses with multiple
|
|
// uniquely named instances should derive from this.
|
|
NamedThread::NamedThread() : Thread() {
|
|
_name = NULL;
|
|
_processed_thread = NULL;
|
|
}
|
|
|
|
NamedThread::~NamedThread() {
|
|
if (_name != NULL) {
|
|
FREE_C_HEAP_ARRAY(char, _name, mtThread);
|
|
_name = NULL;
|
|
}
|
|
}
|
|
|
|
void NamedThread::set_name(const char* format, ...) {
|
|
guarantee(_name == NULL, "Only get to set name once.");
|
|
_name = NEW_C_HEAP_ARRAY(char, max_name_len, mtThread);
|
|
guarantee(_name != NULL, "alloc failure");
|
|
va_list ap;
|
|
va_start(ap, format);
|
|
jio_vsnprintf(_name, max_name_len, format, ap);
|
|
va_end(ap);
|
|
}
|
|
|
|
// ======= WatcherThread ========
|
|
|
|
// The watcher thread exists to simulate timer interrupts. It should
|
|
// be replaced by an abstraction over whatever native support for
|
|
// timer interrupts exists on the platform.
|
|
|
|
WatcherThread* WatcherThread::_watcher_thread = NULL;
|
|
bool WatcherThread::_startable = false;
|
|
volatile bool WatcherThread::_should_terminate = false;
|
|
|
|
WatcherThread::WatcherThread() : Thread(), _crash_protection(NULL) {
|
|
assert(watcher_thread() == NULL, "we can only allocate one WatcherThread");
|
|
if (os::create_thread(this, os::watcher_thread)) {
|
|
_watcher_thread = this;
|
|
|
|
// Set the watcher thread to the highest OS priority which should not be
|
|
// used, unless a Java thread with priority java.lang.Thread.MAX_PRIORITY
|
|
// is created. The only normal thread using this priority is the reference
|
|
// handler thread, which runs for very short intervals only.
|
|
// If the VMThread's priority is not lower than the WatcherThread profiling
|
|
// will be inaccurate.
|
|
os::set_priority(this, MaxPriority);
|
|
if (!DisableStartThread) {
|
|
os::start_thread(this);
|
|
}
|
|
}
|
|
}
|
|
|
|
int WatcherThread::sleep() const {
|
|
MutexLockerEx ml(PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
|
|
|
|
// remaining will be zero if there are no tasks,
|
|
// causing the WatcherThread to sleep until a task is
|
|
// enrolled
|
|
int remaining = PeriodicTask::time_to_wait();
|
|
int time_slept = 0;
|
|
|
|
// we expect this to timeout - we only ever get unparked when
|
|
// we should terminate or when a new task has been enrolled
|
|
OSThreadWaitState osts(this->osthread(), false /* not Object.wait() */);
|
|
|
|
jlong time_before_loop = os::javaTimeNanos();
|
|
|
|
for (;;) {
|
|
bool timedout = PeriodicTask_lock->wait(Mutex::_no_safepoint_check_flag, remaining);
|
|
jlong now = os::javaTimeNanos();
|
|
|
|
if (remaining == 0) {
|
|
// if we didn't have any tasks we could have waited for a long time
|
|
// consider the time_slept zero and reset time_before_loop
|
|
time_slept = 0;
|
|
time_before_loop = now;
|
|
} else {
|
|
// need to recalulate since we might have new tasks in _tasks
|
|
time_slept = (int) ((now - time_before_loop) / 1000000);
|
|
}
|
|
|
|
// Change to task list or spurious wakeup of some kind
|
|
if (timedout || _should_terminate) {
|
|
break;
|
|
}
|
|
|
|
remaining = PeriodicTask::time_to_wait();
|
|
if (remaining == 0) {
|
|
// Last task was just disenrolled so loop around and wait until
|
|
// another task gets enrolled
|
|
continue;
|
|
}
|
|
|
|
remaining -= time_slept;
|
|
if (remaining <= 0)
|
|
break;
|
|
}
|
|
|
|
return time_slept;
|
|
}
|
|
|
|
void WatcherThread::run() {
|
|
assert(this == watcher_thread(), "just checking");
|
|
|
|
this->record_stack_base_and_size();
|
|
this->initialize_thread_local_storage();
|
|
this->set_active_handles(JNIHandleBlock::allocate_block());
|
|
while(!_should_terminate) {
|
|
assert(watcher_thread() == Thread::current(), "thread consistency check");
|
|
assert(watcher_thread() == this, "thread consistency check");
|
|
|
|
// Calculate how long it'll be until the next PeriodicTask work
|
|
// should be done, and sleep that amount of time.
|
|
int time_waited = sleep();
|
|
|
|
if (is_error_reported()) {
|
|
// A fatal error has happened, the error handler(VMError::report_and_die)
|
|
// should abort JVM after creating an error log file. However in some
|
|
// rare cases, the error handler itself might deadlock. Here we try to
|
|
// kill JVM if the fatal error handler fails to abort in 2 minutes.
|
|
//
|
|
// This code is in WatcherThread because WatcherThread wakes up
|
|
// periodically so the fatal error handler doesn't need to do anything;
|
|
// also because the WatcherThread is less likely to crash than other
|
|
// threads.
|
|
|
|
for (;;) {
|
|
if (!ShowMessageBoxOnError
|
|
&& (OnError == NULL || OnError[0] == '\0')
|
|
&& Arguments::abort_hook() == NULL) {
|
|
os::sleep(this, 2 * 60 * 1000, false);
|
|
fdStream err(defaultStream::output_fd());
|
|
err.print_raw_cr("# [ timer expired, abort... ]");
|
|
// skip atexit/vm_exit/vm_abort hooks
|
|
os::die();
|
|
}
|
|
|
|
// Wake up 5 seconds later, the fatal handler may reset OnError or
|
|
// ShowMessageBoxOnError when it is ready to abort.
|
|
os::sleep(this, 5 * 1000, false);
|
|
}
|
|
}
|
|
|
|
PeriodicTask::real_time_tick(time_waited);
|
|
}
|
|
|
|
// Signal that it is terminated
|
|
{
|
|
MutexLockerEx mu(Terminator_lock, Mutex::_no_safepoint_check_flag);
|
|
_watcher_thread = NULL;
|
|
Terminator_lock->notify();
|
|
}
|
|
|
|
// Thread destructor usually does this..
|
|
ThreadLocalStorage::set_thread(NULL);
|
|
}
|
|
|
|
void WatcherThread::start() {
|
|
assert(PeriodicTask_lock->owned_by_self(), "PeriodicTask_lock required");
|
|
|
|
if (watcher_thread() == NULL && _startable) {
|
|
_should_terminate = false;
|
|
// Create the single instance of WatcherThread
|
|
new WatcherThread();
|
|
}
|
|
}
|
|
|
|
void WatcherThread::make_startable() {
|
|
assert(PeriodicTask_lock->owned_by_self(), "PeriodicTask_lock required");
|
|
_startable = true;
|
|
}
|
|
|
|
void WatcherThread::stop() {
|
|
{
|
|
MutexLockerEx ml(PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
|
|
_should_terminate = true;
|
|
OrderAccess::fence(); // ensure WatcherThread sees update in main loop
|
|
|
|
WatcherThread* watcher = watcher_thread();
|
|
if (watcher != NULL)
|
|
watcher->unpark();
|
|
}
|
|
|
|
// it is ok to take late safepoints here, if needed
|
|
MutexLocker mu(Terminator_lock);
|
|
|
|
while(watcher_thread() != NULL) {
|
|
// This wait should make safepoint checks, wait without a timeout,
|
|
// and wait as a suspend-equivalent condition.
|
|
//
|
|
// Note: If the FlatProfiler is running, then this thread is waiting
|
|
// for the WatcherThread to terminate and the WatcherThread, via the
|
|
// FlatProfiler task, is waiting for the external suspend request on
|
|
// this thread to complete. wait_for_ext_suspend_completion() will
|
|
// eventually timeout, but that takes time. Making this wait a
|
|
// suspend-equivalent condition solves that timeout problem.
|
|
//
|
|
Terminator_lock->wait(!Mutex::_no_safepoint_check_flag, 0,
|
|
Mutex::_as_suspend_equivalent_flag);
|
|
}
|
|
}
|
|
|
|
void WatcherThread::unpark() {
|
|
MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ? NULL : PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
|
|
PeriodicTask_lock->notify();
|
|
}
|
|
|
|
void WatcherThread::print_on(outputStream* st) const {
|
|
st->print("\"%s\" ", name());
|
|
Thread::print_on(st);
|
|
st->cr();
|
|
}
|
|
|
|
// ======= JavaThread ========
|
|
|
|
// A JavaThread is a normal Java thread
|
|
|
|
void JavaThread::initialize() {
|
|
// Initialize fields
|
|
|
|
// Set the claimed par_id to -1 (ie not claiming any par_ids)
|
|
set_claimed_par_id(-1);
|
|
|
|
set_saved_exception_pc(NULL);
|
|
set_threadObj(NULL);
|
|
_anchor.clear();
|
|
set_entry_point(NULL);
|
|
set_jni_functions(jni_functions());
|
|
set_callee_target(NULL);
|
|
set_vm_result(NULL);
|
|
set_vm_result_2(NULL);
|
|
set_vframe_array_head(NULL);
|
|
set_vframe_array_last(NULL);
|
|
set_deferred_locals(NULL);
|
|
set_deopt_mark(NULL);
|
|
set_deopt_nmethod(NULL);
|
|
clear_must_deopt_id();
|
|
set_monitor_chunks(NULL);
|
|
set_next(NULL);
|
|
set_thread_state(_thread_new);
|
|
#if INCLUDE_NMT
|
|
set_recorder(NULL);
|
|
#endif
|
|
_terminated = _not_terminated;
|
|
_privileged_stack_top = NULL;
|
|
_array_for_gc = NULL;
|
|
_suspend_equivalent = false;
|
|
_in_deopt_handler = 0;
|
|
_doing_unsafe_access = false;
|
|
_stack_guard_state = stack_guard_unused;
|
|
(void)const_cast<oop&>(_exception_oop = NULL);
|
|
_exception_pc = 0;
|
|
_exception_handler_pc = 0;
|
|
_is_method_handle_return = 0;
|
|
_jvmti_thread_state= NULL;
|
|
_should_post_on_exceptions_flag = JNI_FALSE;
|
|
_jvmti_get_loaded_classes_closure = NULL;
|
|
_interp_only_mode = 0;
|
|
_special_runtime_exit_condition = _no_async_condition;
|
|
_pending_async_exception = NULL;
|
|
_thread_stat = NULL;
|
|
_thread_stat = new ThreadStatistics();
|
|
_blocked_on_compilation = false;
|
|
_jni_active_critical = 0;
|
|
_do_not_unlock_if_synchronized = false;
|
|
_cached_monitor_info = NULL;
|
|
_parker = Parker::Allocate(this) ;
|
|
|
|
#ifndef PRODUCT
|
|
_jmp_ring_index = 0;
|
|
for (int ji = 0 ; ji < jump_ring_buffer_size ; ji++ ) {
|
|
record_jump(NULL, NULL, NULL, 0);
|
|
}
|
|
#endif /* PRODUCT */
|
|
|
|
set_thread_profiler(NULL);
|
|
if (FlatProfiler::is_active()) {
|
|
// This is where we would decide to either give each thread it's own profiler
|
|
// or use one global one from FlatProfiler,
|
|
// or up to some count of the number of profiled threads, etc.
|
|
ThreadProfiler* pp = new ThreadProfiler();
|
|
pp->engage();
|
|
set_thread_profiler(pp);
|
|
}
|
|
|
|
// Setup safepoint state info for this thread
|
|
ThreadSafepointState::create(this);
|
|
|
|
debug_only(_java_call_counter = 0);
|
|
|
|
// JVMTI PopFrame support
|
|
_popframe_condition = popframe_inactive;
|
|
_popframe_preserved_args = NULL;
|
|
_popframe_preserved_args_size = 0;
|
|
|
|
pd_initialize();
|
|
}
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
SATBMarkQueueSet JavaThread::_satb_mark_queue_set;
|
|
DirtyCardQueueSet JavaThread::_dirty_card_queue_set;
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
JavaThread::JavaThread(bool is_attaching_via_jni) :
|
|
Thread()
|
|
#if INCLUDE_ALL_GCS
|
|
, _satb_mark_queue(&_satb_mark_queue_set),
|
|
_dirty_card_queue(&_dirty_card_queue_set)
|
|
#endif // INCLUDE_ALL_GCS
|
|
{
|
|
initialize();
|
|
if (is_attaching_via_jni) {
|
|
_jni_attach_state = _attaching_via_jni;
|
|
} else {
|
|
_jni_attach_state = _not_attaching_via_jni;
|
|
}
|
|
assert(deferred_card_mark().is_empty(), "Default MemRegion ctor");
|
|
_safepoint_visible = false;
|
|
}
|
|
|
|
bool JavaThread::reguard_stack(address cur_sp) {
|
|
if (_stack_guard_state != stack_guard_yellow_disabled) {
|
|
return true; // Stack already guarded or guard pages not needed.
|
|
}
|
|
|
|
if (register_stack_overflow()) {
|
|
// For those architectures which have separate register and
|
|
// memory stacks, we must check the register stack to see if
|
|
// it has overflowed.
|
|
return false;
|
|
}
|
|
|
|
// Java code never executes within the yellow zone: the latter is only
|
|
// there to provoke an exception during stack banging. If java code
|
|
// is executing there, either StackShadowPages should be larger, or
|
|
// some exception code in c1, c2 or the interpreter isn't unwinding
|
|
// when it should.
|
|
guarantee(cur_sp > stack_yellow_zone_base(), "not enough space to reguard - increase StackShadowPages");
|
|
|
|
enable_stack_yellow_zone();
|
|
return true;
|
|
}
|
|
|
|
bool JavaThread::reguard_stack(void) {
|
|
return reguard_stack(os::current_stack_pointer());
|
|
}
|
|
|
|
|
|
void JavaThread::block_if_vm_exited() {
|
|
if (_terminated == _vm_exited) {
|
|
// _vm_exited is set at safepoint, and Threads_lock is never released
|
|
// we will block here forever
|
|
Threads_lock->lock_without_safepoint_check();
|
|
ShouldNotReachHere();
|
|
}
|
|
}
|
|
|
|
|
|
// Remove this ifdef when C1 is ported to the compiler interface.
|
|
static void compiler_thread_entry(JavaThread* thread, TRAPS);
|
|
|
|
JavaThread::JavaThread(ThreadFunction entry_point, size_t stack_sz) :
|
|
Thread()
|
|
#if INCLUDE_ALL_GCS
|
|
, _satb_mark_queue(&_satb_mark_queue_set),
|
|
_dirty_card_queue(&_dirty_card_queue_set)
|
|
#endif // INCLUDE_ALL_GCS
|
|
{
|
|
if (TraceThreadEvents) {
|
|
tty->print_cr("creating thread %p", this);
|
|
}
|
|
initialize();
|
|
_jni_attach_state = _not_attaching_via_jni;
|
|
set_entry_point(entry_point);
|
|
// Create the native thread itself.
|
|
// %note runtime_23
|
|
os::ThreadType thr_type = os::java_thread;
|
|
thr_type = entry_point == &compiler_thread_entry ? os::compiler_thread :
|
|
os::java_thread;
|
|
os::create_thread(this, thr_type, stack_sz);
|
|
_safepoint_visible = false;
|
|
// The _osthread may be NULL here because we ran out of memory (too many threads active).
|
|
// We need to throw and OutOfMemoryError - however we cannot do this here because the caller
|
|
// may hold a lock and all locks must be unlocked before throwing the exception (throwing
|
|
// the exception consists of creating the exception object & initializing it, initialization
|
|
// will leave the VM via a JavaCall and then all locks must be unlocked).
|
|
//
|
|
// The thread is still suspended when we reach here. Thread must be explicit started
|
|
// by creator! Furthermore, the thread must also explicitly be added to the Threads list
|
|
// by calling Threads:add. The reason why this is not done here, is because the thread
|
|
// object must be fully initialized (take a look at JVM_Start)
|
|
}
|
|
|
|
JavaThread::~JavaThread() {
|
|
if (TraceThreadEvents) {
|
|
tty->print_cr("terminate thread %p", this);
|
|
}
|
|
|
|
// By now, this thread should already be invisible to safepoint,
|
|
// and its per-thread recorder also collected.
|
|
assert(!is_safepoint_visible(), "wrong state");
|
|
#if INCLUDE_NMT
|
|
assert(get_recorder() == NULL, "Already collected");
|
|
#endif // INCLUDE_NMT
|
|
|
|
// JSR166 -- return the parker to the free list
|
|
Parker::Release(_parker);
|
|
_parker = NULL ;
|
|
|
|
// Free any remaining previous UnrollBlock
|
|
vframeArray* old_array = vframe_array_last();
|
|
|
|
if (old_array != NULL) {
|
|
Deoptimization::UnrollBlock* old_info = old_array->unroll_block();
|
|
old_array->set_unroll_block(NULL);
|
|
delete old_info;
|
|
delete old_array;
|
|
}
|
|
|
|
GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred = deferred_locals();
|
|
if (deferred != NULL) {
|
|
// This can only happen if thread is destroyed before deoptimization occurs.
|
|
assert(deferred->length() != 0, "empty array!");
|
|
do {
|
|
jvmtiDeferredLocalVariableSet* dlv = deferred->at(0);
|
|
deferred->remove_at(0);
|
|
// individual jvmtiDeferredLocalVariableSet are CHeapObj's
|
|
delete dlv;
|
|
} while (deferred->length() != 0);
|
|
delete deferred;
|
|
}
|
|
|
|
// All Java related clean up happens in exit
|
|
ThreadSafepointState::destroy(this);
|
|
if (_thread_profiler != NULL) delete _thread_profiler;
|
|
if (_thread_stat != NULL) delete _thread_stat;
|
|
}
|
|
|
|
|
|
// The first routine called by a new Java thread
|
|
void JavaThread::run() {
|
|
// initialize thread-local alloc buffer related fields
|
|
this->initialize_tlab();
|
|
|
|
// used to test validitity of stack trace backs
|
|
this->record_base_of_stack_pointer();
|
|
|
|
// Record real stack base and size.
|
|
this->record_stack_base_and_size();
|
|
|
|
// Initialize thread local storage; set before calling MutexLocker
|
|
this->initialize_thread_local_storage();
|
|
|
|
this->create_stack_guard_pages();
|
|
|
|
this->cache_global_variables();
|
|
|
|
// Thread is now sufficient initialized to be handled by the safepoint code as being
|
|
// in the VM. Change thread state from _thread_new to _thread_in_vm
|
|
ThreadStateTransition::transition_and_fence(this, _thread_new, _thread_in_vm);
|
|
|
|
assert(JavaThread::current() == this, "sanity check");
|
|
assert(!Thread::current()->owns_locks(), "sanity check");
|
|
|
|
DTRACE_THREAD_PROBE(start, this);
|
|
|
|
// This operation might block. We call that after all safepoint checks for a new thread has
|
|
// been completed.
|
|
this->set_active_handles(JNIHandleBlock::allocate_block());
|
|
|
|
if (JvmtiExport::should_post_thread_life()) {
|
|
JvmtiExport::post_thread_start(this);
|
|
}
|
|
|
|
EventThreadStart event;
|
|
if (event.should_commit()) {
|
|
event.set_javalangthread(java_lang_Thread::thread_id(this->threadObj()));
|
|
event.commit();
|
|
}
|
|
|
|
// We call another function to do the rest so we are sure that the stack addresses used
|
|
// from there will be lower than the stack base just computed
|
|
thread_main_inner();
|
|
|
|
// Note, thread is no longer valid at this point!
|
|
}
|
|
|
|
|
|
void JavaThread::thread_main_inner() {
|
|
assert(JavaThread::current() == this, "sanity check");
|
|
assert(this->threadObj() != NULL, "just checking");
|
|
|
|
// Execute thread entry point unless this thread has a pending exception
|
|
// or has been stopped before starting.
|
|
// Note: Due to JVM_StopThread we can have pending exceptions already!
|
|
if (!this->has_pending_exception() &&
|
|
!java_lang_Thread::is_stillborn(this->threadObj())) {
|
|
{
|
|
ResourceMark rm(this);
|
|
this->set_native_thread_name(this->get_thread_name());
|
|
}
|
|
HandleMark hm(this);
|
|
this->entry_point()(this, this);
|
|
}
|
|
|
|
DTRACE_THREAD_PROBE(stop, this);
|
|
|
|
this->exit(false);
|
|
delete this;
|
|
}
|
|
|
|
|
|
static void ensure_join(JavaThread* thread) {
|
|
// We do not need to grap the Threads_lock, since we are operating on ourself.
|
|
Handle threadObj(thread, thread->threadObj());
|
|
assert(threadObj.not_null(), "java thread object must exist");
|
|
ObjectLocker lock(threadObj, thread);
|
|
// Ignore pending exception (ThreadDeath), since we are exiting anyway
|
|
thread->clear_pending_exception();
|
|
// Thread is exiting. So set thread_status field in java.lang.Thread class to TERMINATED.
|
|
java_lang_Thread::set_thread_status(threadObj(), java_lang_Thread::TERMINATED);
|
|
// Clear the native thread instance - this makes isAlive return false and allows the join()
|
|
// to complete once we've done the notify_all below
|
|
java_lang_Thread::set_thread(threadObj(), NULL);
|
|
lock.notify_all(thread);
|
|
// Ignore pending exception (ThreadDeath), since we are exiting anyway
|
|
thread->clear_pending_exception();
|
|
}
|
|
|
|
|
|
// For any new cleanup additions, please check to see if they need to be applied to
|
|
// cleanup_failed_attach_current_thread as well.
|
|
void JavaThread::exit(bool destroy_vm, ExitType exit_type) {
|
|
assert(this == JavaThread::current(), "thread consistency check");
|
|
|
|
HandleMark hm(this);
|
|
Handle uncaught_exception(this, this->pending_exception());
|
|
this->clear_pending_exception();
|
|
Handle threadObj(this, this->threadObj());
|
|
assert(threadObj.not_null(), "Java thread object should be created");
|
|
|
|
if (get_thread_profiler() != NULL) {
|
|
get_thread_profiler()->disengage();
|
|
ResourceMark rm;
|
|
get_thread_profiler()->print(get_thread_name());
|
|
}
|
|
|
|
|
|
// FIXIT: This code should be moved into else part, when reliable 1.2/1.3 check is in place
|
|
{
|
|
EXCEPTION_MARK;
|
|
|
|
CLEAR_PENDING_EXCEPTION;
|
|
}
|
|
// FIXIT: The is_null check is only so it works better on JDK1.2 VM's. This
|
|
// has to be fixed by a runtime query method
|
|
if (!destroy_vm || JDK_Version::is_jdk12x_version()) {
|
|
// JSR-166: change call from from ThreadGroup.uncaughtException to
|
|
// java.lang.Thread.dispatchUncaughtException
|
|
if (uncaught_exception.not_null()) {
|
|
Handle group(this, java_lang_Thread::threadGroup(threadObj()));
|
|
{
|
|
EXCEPTION_MARK;
|
|
// Check if the method Thread.dispatchUncaughtException() exists. If so
|
|
// call it. Otherwise we have an older library without the JSR-166 changes,
|
|
// so call ThreadGroup.uncaughtException()
|
|
KlassHandle recvrKlass(THREAD, threadObj->klass());
|
|
CallInfo callinfo;
|
|
KlassHandle thread_klass(THREAD, SystemDictionary::Thread_klass());
|
|
LinkResolver::resolve_virtual_call(callinfo, threadObj, recvrKlass, thread_klass,
|
|
vmSymbols::dispatchUncaughtException_name(),
|
|
vmSymbols::throwable_void_signature(),
|
|
KlassHandle(), false, false, THREAD);
|
|
CLEAR_PENDING_EXCEPTION;
|
|
methodHandle method = callinfo.selected_method();
|
|
if (method.not_null()) {
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_virtual(&result,
|
|
threadObj, thread_klass,
|
|
vmSymbols::dispatchUncaughtException_name(),
|
|
vmSymbols::throwable_void_signature(),
|
|
uncaught_exception,
|
|
THREAD);
|
|
} else {
|
|
KlassHandle thread_group(THREAD, SystemDictionary::ThreadGroup_klass());
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_virtual(&result,
|
|
group, thread_group,
|
|
vmSymbols::uncaughtException_name(),
|
|
vmSymbols::thread_throwable_void_signature(),
|
|
threadObj, // Arg 1
|
|
uncaught_exception, // Arg 2
|
|
THREAD);
|
|
}
|
|
if (HAS_PENDING_EXCEPTION) {
|
|
ResourceMark rm(this);
|
|
jio_fprintf(defaultStream::error_stream(),
|
|
"\nException: %s thrown from the UncaughtExceptionHandler"
|
|
" in thread \"%s\"\n",
|
|
pending_exception()->klass()->external_name(),
|
|
get_thread_name());
|
|
CLEAR_PENDING_EXCEPTION;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Called before the java thread exit since we want to read info
|
|
// from java_lang_Thread object
|
|
EventThreadEnd event;
|
|
if (event.should_commit()) {
|
|
event.set_javalangthread(java_lang_Thread::thread_id(this->threadObj()));
|
|
event.commit();
|
|
}
|
|
|
|
// Call after last event on thread
|
|
EVENT_THREAD_EXIT(this);
|
|
|
|
// Call Thread.exit(). We try 3 times in case we got another Thread.stop during
|
|
// the execution of the method. If that is not enough, then we don't really care. Thread.stop
|
|
// is deprecated anyhow.
|
|
if (!is_Compiler_thread()) {
|
|
int count = 3;
|
|
while (java_lang_Thread::threadGroup(threadObj()) != NULL && (count-- > 0)) {
|
|
EXCEPTION_MARK;
|
|
JavaValue result(T_VOID);
|
|
KlassHandle thread_klass(THREAD, SystemDictionary::Thread_klass());
|
|
JavaCalls::call_virtual(&result,
|
|
threadObj, thread_klass,
|
|
vmSymbols::exit_method_name(),
|
|
vmSymbols::void_method_signature(),
|
|
THREAD);
|
|
CLEAR_PENDING_EXCEPTION;
|
|
}
|
|
}
|
|
// notify JVMTI
|
|
if (JvmtiExport::should_post_thread_life()) {
|
|
JvmtiExport::post_thread_end(this);
|
|
}
|
|
|
|
// We have notified the agents that we are exiting, before we go on,
|
|
// we must check for a pending external suspend request and honor it
|
|
// in order to not surprise the thread that made the suspend request.
|
|
while (true) {
|
|
{
|
|
MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
if (!is_external_suspend()) {
|
|
set_terminated(_thread_exiting);
|
|
ThreadService::current_thread_exiting(this);
|
|
break;
|
|
}
|
|
// Implied else:
|
|
// Things get a little tricky here. We have a pending external
|
|
// suspend request, but we are holding the SR_lock so we
|
|
// can't just self-suspend. So we temporarily drop the lock
|
|
// and then self-suspend.
|
|
}
|
|
|
|
ThreadBlockInVM tbivm(this);
|
|
java_suspend_self();
|
|
|
|
// We're done with this suspend request, but we have to loop around
|
|
// and check again. Eventually we will get SR_lock without a pending
|
|
// external suspend request and will be able to mark ourselves as
|
|
// exiting.
|
|
}
|
|
// no more external suspends are allowed at this point
|
|
} else {
|
|
// before_exit() has already posted JVMTI THREAD_END events
|
|
}
|
|
|
|
// Notify waiters on thread object. This has to be done after exit() is called
|
|
// on the thread (if the thread is the last thread in a daemon ThreadGroup the
|
|
// group should have the destroyed bit set before waiters are notified).
|
|
ensure_join(this);
|
|
assert(!this->has_pending_exception(), "ensure_join should have cleared");
|
|
|
|
// 6282335 JNI DetachCurrentThread spec states that all Java monitors
|
|
// held by this thread must be released. A detach operation must only
|
|
// get here if there are no Java frames on the stack. Therefore, any
|
|
// owned monitors at this point MUST be JNI-acquired monitors which are
|
|
// pre-inflated and in the monitor cache.
|
|
//
|
|
// ensure_join() ignores IllegalThreadStateExceptions, and so does this.
|
|
if (exit_type == jni_detach && JNIDetachReleasesMonitors) {
|
|
assert(!this->has_last_Java_frame(), "detaching with Java frames?");
|
|
ObjectSynchronizer::release_monitors_owned_by_thread(this);
|
|
assert(!this->has_pending_exception(), "release_monitors should have cleared");
|
|
}
|
|
|
|
// These things needs to be done while we are still a Java Thread. Make sure that thread
|
|
// is in a consistent state, in case GC happens
|
|
assert(_privileged_stack_top == NULL, "must be NULL when we get here");
|
|
|
|
if (active_handles() != NULL) {
|
|
JNIHandleBlock* block = active_handles();
|
|
set_active_handles(NULL);
|
|
JNIHandleBlock::release_block(block);
|
|
}
|
|
|
|
if (free_handle_block() != NULL) {
|
|
JNIHandleBlock* block = free_handle_block();
|
|
set_free_handle_block(NULL);
|
|
JNIHandleBlock::release_block(block);
|
|
}
|
|
|
|
// These have to be removed while this is still a valid thread.
|
|
remove_stack_guard_pages();
|
|
|
|
if (UseTLAB) {
|
|
tlab().make_parsable(true); // retire TLAB
|
|
}
|
|
|
|
if (JvmtiEnv::environments_might_exist()) {
|
|
JvmtiExport::cleanup_thread(this);
|
|
}
|
|
|
|
// We must flush any deferred card marks before removing a thread from
|
|
// the list of active threads.
|
|
Universe::heap()->flush_deferred_store_barrier(this);
|
|
assert(deferred_card_mark().is_empty(), "Should have been flushed");
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
// We must flush the G1-related buffers before removing a thread
|
|
// from the list of active threads. We must do this after any deferred
|
|
// card marks have been flushed (above) so that any entries that are
|
|
// added to the thread's dirty card queue as a result are not lost.
|
|
if (UseG1GC) {
|
|
flush_barrier_queues();
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
// Remove from list of active threads list, and notify VM thread if we are the last non-daemon thread
|
|
Threads::remove(this);
|
|
}
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
// Flush G1-related queues.
|
|
void JavaThread::flush_barrier_queues() {
|
|
satb_mark_queue().flush();
|
|
dirty_card_queue().flush();
|
|
}
|
|
|
|
void JavaThread::initialize_queues() {
|
|
assert(!SafepointSynchronize::is_at_safepoint(),
|
|
"we should not be at a safepoint");
|
|
|
|
ObjPtrQueue& satb_queue = satb_mark_queue();
|
|
SATBMarkQueueSet& satb_queue_set = satb_mark_queue_set();
|
|
// The SATB queue should have been constructed with its active
|
|
// field set to false.
|
|
assert(!satb_queue.is_active(), "SATB queue should not be active");
|
|
assert(satb_queue.is_empty(), "SATB queue should be empty");
|
|
// If we are creating the thread during a marking cycle, we should
|
|
// set the active field of the SATB queue to true.
|
|
if (satb_queue_set.is_active()) {
|
|
satb_queue.set_active(true);
|
|
}
|
|
|
|
DirtyCardQueue& dirty_queue = dirty_card_queue();
|
|
// The dirty card queue should have been constructed with its
|
|
// active field set to true.
|
|
assert(dirty_queue.is_active(), "dirty card queue should be active");
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
void JavaThread::cleanup_failed_attach_current_thread() {
|
|
if (get_thread_profiler() != NULL) {
|
|
get_thread_profiler()->disengage();
|
|
ResourceMark rm;
|
|
get_thread_profiler()->print(get_thread_name());
|
|
}
|
|
|
|
if (active_handles() != NULL) {
|
|
JNIHandleBlock* block = active_handles();
|
|
set_active_handles(NULL);
|
|
JNIHandleBlock::release_block(block);
|
|
}
|
|
|
|
if (free_handle_block() != NULL) {
|
|
JNIHandleBlock* block = free_handle_block();
|
|
set_free_handle_block(NULL);
|
|
JNIHandleBlock::release_block(block);
|
|
}
|
|
|
|
// These have to be removed while this is still a valid thread.
|
|
remove_stack_guard_pages();
|
|
|
|
if (UseTLAB) {
|
|
tlab().make_parsable(true); // retire TLAB, if any
|
|
}
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
if (UseG1GC) {
|
|
flush_barrier_queues();
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
Threads::remove(this);
|
|
delete this;
|
|
}
|
|
|
|
|
|
|
|
|
|
JavaThread* JavaThread::active() {
|
|
Thread* thread = ThreadLocalStorage::thread();
|
|
assert(thread != NULL, "just checking");
|
|
if (thread->is_Java_thread()) {
|
|
return (JavaThread*) thread;
|
|
} else {
|
|
assert(thread->is_VM_thread(), "this must be a vm thread");
|
|
VM_Operation* op = ((VMThread*) thread)->vm_operation();
|
|
JavaThread *ret=op == NULL ? NULL : (JavaThread *)op->calling_thread();
|
|
assert(ret->is_Java_thread(), "must be a Java thread");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
bool JavaThread::is_lock_owned(address adr) const {
|
|
if (Thread::is_lock_owned(adr)) return true;
|
|
|
|
for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) {
|
|
if (chunk->contains(adr)) return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
void JavaThread::add_monitor_chunk(MonitorChunk* chunk) {
|
|
chunk->set_next(monitor_chunks());
|
|
set_monitor_chunks(chunk);
|
|
}
|
|
|
|
void JavaThread::remove_monitor_chunk(MonitorChunk* chunk) {
|
|
guarantee(monitor_chunks() != NULL, "must be non empty");
|
|
if (monitor_chunks() == chunk) {
|
|
set_monitor_chunks(chunk->next());
|
|
} else {
|
|
MonitorChunk* prev = monitor_chunks();
|
|
while (prev->next() != chunk) prev = prev->next();
|
|
prev->set_next(chunk->next());
|
|
}
|
|
}
|
|
|
|
// JVM support.
|
|
|
|
// Note: this function shouldn't block if it's called in
|
|
// _thread_in_native_trans state (such as from
|
|
// check_special_condition_for_native_trans()).
|
|
void JavaThread::check_and_handle_async_exceptions(bool check_unsafe_error) {
|
|
|
|
if (has_last_Java_frame() && has_async_condition()) {
|
|
// If we are at a polling page safepoint (not a poll return)
|
|
// then we must defer async exception because live registers
|
|
// will be clobbered by the exception path. Poll return is
|
|
// ok because the call we a returning from already collides
|
|
// with exception handling registers and so there is no issue.
|
|
// (The exception handling path kills call result registers but
|
|
// this is ok since the exception kills the result anyway).
|
|
|
|
if (is_at_poll_safepoint()) {
|
|
// if the code we are returning to has deoptimized we must defer
|
|
// the exception otherwise live registers get clobbered on the
|
|
// exception path before deoptimization is able to retrieve them.
|
|
//
|
|
RegisterMap map(this, false);
|
|
frame caller_fr = last_frame().sender(&map);
|
|
assert(caller_fr.is_compiled_frame(), "what?");
|
|
if (caller_fr.is_deoptimized_frame()) {
|
|
if (TraceExceptions) {
|
|
ResourceMark rm;
|
|
tty->print_cr("deferred async exception at compiled safepoint");
|
|
}
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
JavaThread::AsyncRequests condition = clear_special_runtime_exit_condition();
|
|
if (condition == _no_async_condition) {
|
|
// Conditions have changed since has_special_runtime_exit_condition()
|
|
// was called:
|
|
// - if we were here only because of an external suspend request,
|
|
// then that was taken care of above (or cancelled) so we are done
|
|
// - if we were here because of another async request, then it has
|
|
// been cleared between the has_special_runtime_exit_condition()
|
|
// and now so again we are done
|
|
return;
|
|
}
|
|
|
|
// Check for pending async. exception
|
|
if (_pending_async_exception != NULL) {
|
|
// Only overwrite an already pending exception, if it is not a threadDeath.
|
|
if (!has_pending_exception() || !pending_exception()->is_a(SystemDictionary::ThreadDeath_klass())) {
|
|
|
|
// We cannot call Exceptions::_throw(...) here because we cannot block
|
|
set_pending_exception(_pending_async_exception, __FILE__, __LINE__);
|
|
|
|
if (TraceExceptions) {
|
|
ResourceMark rm;
|
|
tty->print("Async. exception installed at runtime exit (" INTPTR_FORMAT ")", this);
|
|
if (has_last_Java_frame() ) {
|
|
frame f = last_frame();
|
|
tty->print(" (pc: " INTPTR_FORMAT " sp: " INTPTR_FORMAT " )", f.pc(), f.sp());
|
|
}
|
|
tty->print_cr(" of type: %s", InstanceKlass::cast(_pending_async_exception->klass())->external_name());
|
|
}
|
|
_pending_async_exception = NULL;
|
|
clear_has_async_exception();
|
|
}
|
|
}
|
|
|
|
if (check_unsafe_error &&
|
|
condition == _async_unsafe_access_error && !has_pending_exception()) {
|
|
condition = _no_async_condition; // done
|
|
switch (thread_state()) {
|
|
case _thread_in_vm:
|
|
{
|
|
JavaThread* THREAD = this;
|
|
THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in an unsafe memory access operation");
|
|
}
|
|
case _thread_in_native:
|
|
{
|
|
ThreadInVMfromNative tiv(this);
|
|
JavaThread* THREAD = this;
|
|
THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in an unsafe memory access operation");
|
|
}
|
|
case _thread_in_Java:
|
|
{
|
|
ThreadInVMfromJava tiv(this);
|
|
JavaThread* THREAD = this;
|
|
THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in a recent unsafe memory access operation in compiled Java code");
|
|
}
|
|
default:
|
|
ShouldNotReachHere();
|
|
}
|
|
}
|
|
|
|
assert(condition == _no_async_condition || has_pending_exception() ||
|
|
(!check_unsafe_error && condition == _async_unsafe_access_error),
|
|
"must have handled the async condition, if no exception");
|
|
}
|
|
|
|
void JavaThread::handle_special_runtime_exit_condition(bool check_asyncs) {
|
|
//
|
|
// Check for pending external suspend. Internal suspend requests do
|
|
// not use handle_special_runtime_exit_condition().
|
|
// If JNIEnv proxies are allowed, don't self-suspend if the target
|
|
// thread is not the current thread. In older versions of jdbx, jdbx
|
|
// threads could call into the VM with another thread's JNIEnv so we
|
|
// can be here operating on behalf of a suspended thread (4432884).
|
|
bool do_self_suspend = is_external_suspend_with_lock();
|
|
if (do_self_suspend && (!AllowJNIEnvProxy || this == JavaThread::current())) {
|
|
//
|
|
// Because thread is external suspended the safepoint code will count
|
|
// thread as at a safepoint. This can be odd because we can be here
|
|
// as _thread_in_Java which would normally transition to _thread_blocked
|
|
// at a safepoint. We would like to mark the thread as _thread_blocked
|
|
// before calling java_suspend_self like all other callers of it but
|
|
// we must then observe proper safepoint protocol. (We can't leave
|
|
// _thread_blocked with a safepoint in progress). However we can be
|
|
// here as _thread_in_native_trans so we can't use a normal transition
|
|
// constructor/destructor pair because they assert on that type of
|
|
// transition. We could do something like:
|
|
//
|
|
// JavaThreadState state = thread_state();
|
|
// set_thread_state(_thread_in_vm);
|
|
// {
|
|
// ThreadBlockInVM tbivm(this);
|
|
// java_suspend_self()
|
|
// }
|
|
// set_thread_state(_thread_in_vm_trans);
|
|
// if (safepoint) block;
|
|
// set_thread_state(state);
|
|
//
|
|
// but that is pretty messy. Instead we just go with the way the
|
|
// code has worked before and note that this is the only path to
|
|
// java_suspend_self that doesn't put the thread in _thread_blocked
|
|
// mode.
|
|
|
|
frame_anchor()->make_walkable(this);
|
|
java_suspend_self();
|
|
|
|
// We might be here for reasons in addition to the self-suspend request
|
|
// so check for other async requests.
|
|
}
|
|
|
|
if (check_asyncs) {
|
|
check_and_handle_async_exceptions();
|
|
}
|
|
}
|
|
|
|
void JavaThread::send_thread_stop(oop java_throwable) {
|
|
assert(Thread::current()->is_VM_thread(), "should be in the vm thread");
|
|
assert(Threads_lock->is_locked(), "Threads_lock should be locked by safepoint code");
|
|
assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
|
|
|
|
// Do not throw asynchronous exceptions against the compiler thread
|
|
// (the compiler thread should not be a Java thread -- fix in 1.4.2)
|
|
if (is_Compiler_thread()) return;
|
|
|
|
{
|
|
// Actually throw the Throwable against the target Thread - however
|
|
// only if there is no thread death exception installed already.
|
|
if (_pending_async_exception == NULL || !_pending_async_exception->is_a(SystemDictionary::ThreadDeath_klass())) {
|
|
// If the topmost frame is a runtime stub, then we are calling into
|
|
// OptoRuntime from compiled code. Some runtime stubs (new, monitor_exit..)
|
|
// must deoptimize the caller before continuing, as the compiled exception handler table
|
|
// may not be valid
|
|
if (has_last_Java_frame()) {
|
|
frame f = last_frame();
|
|
if (f.is_runtime_frame() || f.is_safepoint_blob_frame()) {
|
|
// BiasedLocking needs an updated RegisterMap for the revoke monitors pass
|
|
RegisterMap reg_map(this, UseBiasedLocking);
|
|
frame compiled_frame = f.sender(®_map);
|
|
if (!StressCompiledExceptionHandlers && compiled_frame.can_be_deoptimized()) {
|
|
Deoptimization::deoptimize(this, compiled_frame, ®_map);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Set async. pending exception in thread.
|
|
set_pending_async_exception(java_throwable);
|
|
|
|
if (TraceExceptions) {
|
|
ResourceMark rm;
|
|
tty->print_cr("Pending Async. exception installed of type: %s", InstanceKlass::cast(_pending_async_exception->klass())->external_name());
|
|
}
|
|
// for AbortVMOnException flag
|
|
NOT_PRODUCT(Exceptions::debug_check_abort(InstanceKlass::cast(_pending_async_exception->klass())->external_name()));
|
|
}
|
|
}
|
|
|
|
|
|
// Interrupt thread so it will wake up from a potential wait()
|
|
Thread::interrupt(this);
|
|
}
|
|
|
|
// External suspension mechanism.
|
|
//
|
|
// Tell the VM to suspend a thread when ever it knows that it does not hold on
|
|
// to any VM_locks and it is at a transition
|
|
// Self-suspension will happen on the transition out of the vm.
|
|
// Catch "this" coming in from JNIEnv pointers when the thread has been freed
|
|
//
|
|
// Guarantees on return:
|
|
// + Target thread will not execute any new bytecode (that's why we need to
|
|
// force a safepoint)
|
|
// + Target thread will not enter any new monitors
|
|
//
|
|
void JavaThread::java_suspend() {
|
|
{ MutexLocker mu(Threads_lock);
|
|
if (!Threads::includes(this) || is_exiting() || this->threadObj() == NULL) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
{ MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
if (!is_external_suspend()) {
|
|
// a racing resume has cancelled us; bail out now
|
|
return;
|
|
}
|
|
|
|
// suspend is done
|
|
uint32_t debug_bits = 0;
|
|
// Warning: is_ext_suspend_completed() may temporarily drop the
|
|
// SR_lock to allow the thread to reach a stable thread state if
|
|
// it is currently in a transient thread state.
|
|
if (is_ext_suspend_completed(false /* !called_by_wait */,
|
|
SuspendRetryDelay, &debug_bits) ) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
VM_ForceSafepoint vm_suspend;
|
|
VMThread::execute(&vm_suspend);
|
|
}
|
|
|
|
// Part II of external suspension.
|
|
// A JavaThread self suspends when it detects a pending external suspend
|
|
// request. This is usually on transitions. It is also done in places
|
|
// where continuing to the next transition would surprise the caller,
|
|
// e.g., monitor entry.
|
|
//
|
|
// Returns the number of times that the thread self-suspended.
|
|
//
|
|
// Note: DO NOT call java_suspend_self() when you just want to block current
|
|
// thread. java_suspend_self() is the second stage of cooperative
|
|
// suspension for external suspend requests and should only be used
|
|
// to complete an external suspend request.
|
|
//
|
|
int JavaThread::java_suspend_self() {
|
|
int ret = 0;
|
|
|
|
// we are in the process of exiting so don't suspend
|
|
if (is_exiting()) {
|
|
clear_external_suspend();
|
|
return ret;
|
|
}
|
|
|
|
assert(_anchor.walkable() ||
|
|
(is_Java_thread() && !((JavaThread*)this)->has_last_Java_frame()),
|
|
"must have walkable stack");
|
|
|
|
MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
|
|
assert(!this->is_ext_suspended(),
|
|
"a thread trying to self-suspend should not already be suspended");
|
|
|
|
if (this->is_suspend_equivalent()) {
|
|
// If we are self-suspending as a result of the lifting of a
|
|
// suspend equivalent condition, then the suspend_equivalent
|
|
// flag is not cleared until we set the ext_suspended flag so
|
|
// that wait_for_ext_suspend_completion() returns consistent
|
|
// results.
|
|
this->clear_suspend_equivalent();
|
|
}
|
|
|
|
// A racing resume may have cancelled us before we grabbed SR_lock
|
|
// above. Or another external suspend request could be waiting for us
|
|
// by the time we return from SR_lock()->wait(). The thread
|
|
// that requested the suspension may already be trying to walk our
|
|
// stack and if we return now, we can change the stack out from under
|
|
// it. This would be a "bad thing (TM)" and cause the stack walker
|
|
// to crash. We stay self-suspended until there are no more pending
|
|
// external suspend requests.
|
|
while (is_external_suspend()) {
|
|
ret++;
|
|
this->set_ext_suspended();
|
|
|
|
// _ext_suspended flag is cleared by java_resume()
|
|
while (is_ext_suspended()) {
|
|
this->SR_lock()->wait(Mutex::_no_safepoint_check_flag);
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef ASSERT
|
|
// verify the JavaThread has not yet been published in the Threads::list, and
|
|
// hence doesn't need protection from concurrent access at this stage
|
|
void JavaThread::verify_not_published() {
|
|
if (!Threads_lock->owned_by_self()) {
|
|
MutexLockerEx ml(Threads_lock, Mutex::_no_safepoint_check_flag);
|
|
assert( !Threads::includes(this),
|
|
"java thread shouldn't have been published yet!");
|
|
}
|
|
else {
|
|
assert( !Threads::includes(this),
|
|
"java thread shouldn't have been published yet!");
|
|
}
|
|
}
|
|
#endif
|
|
|
|
// Slow path when the native==>VM/Java barriers detect a safepoint is in
|
|
// progress or when _suspend_flags is non-zero.
|
|
// Current thread needs to self-suspend if there is a suspend request and/or
|
|
// block if a safepoint is in progress.
|
|
// Async exception ISN'T checked.
|
|
// Note only the ThreadInVMfromNative transition can call this function
|
|
// directly and when thread state is _thread_in_native_trans
|
|
void JavaThread::check_safepoint_and_suspend_for_native_trans(JavaThread *thread) {
|
|
assert(thread->thread_state() == _thread_in_native_trans, "wrong state");
|
|
|
|
JavaThread *curJT = JavaThread::current();
|
|
bool do_self_suspend = thread->is_external_suspend();
|
|
|
|
assert(!curJT->has_last_Java_frame() || curJT->frame_anchor()->walkable(), "Unwalkable stack in native->vm transition");
|
|
|
|
// If JNIEnv proxies are allowed, don't self-suspend if the target
|
|
// thread is not the current thread. In older versions of jdbx, jdbx
|
|
// threads could call into the VM with another thread's JNIEnv so we
|
|
// can be here operating on behalf of a suspended thread (4432884).
|
|
if (do_self_suspend && (!AllowJNIEnvProxy || curJT == thread)) {
|
|
JavaThreadState state = thread->thread_state();
|
|
|
|
// We mark this thread_blocked state as a suspend-equivalent so
|
|
// that a caller to is_ext_suspend_completed() won't be confused.
|
|
// The suspend-equivalent state is cleared by java_suspend_self().
|
|
thread->set_suspend_equivalent();
|
|
|
|
// If the safepoint code sees the _thread_in_native_trans state, it will
|
|
// wait until the thread changes to other thread state. There is no
|
|
// guarantee on how soon we can obtain the SR_lock and complete the
|
|
// self-suspend request. It would be a bad idea to let safepoint wait for
|
|
// too long. Temporarily change the state to _thread_blocked to
|
|
// let the VM thread know that this thread is ready for GC. The problem
|
|
// of changing thread state is that safepoint could happen just after
|
|
// java_suspend_self() returns after being resumed, and VM thread will
|
|
// see the _thread_blocked state. We must check for safepoint
|
|
// after restoring the state and make sure we won't leave while a safepoint
|
|
// is in progress.
|
|
thread->set_thread_state(_thread_blocked);
|
|
thread->java_suspend_self();
|
|
thread->set_thread_state(state);
|
|
// 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()) {
|
|
// If we are safepointing, then block the caller which may not be
|
|
// the same as the target thread (see above).
|
|
SafepointSynchronize::block(curJT);
|
|
}
|
|
|
|
if (thread->is_deopt_suspend()) {
|
|
thread->clear_deopt_suspend();
|
|
RegisterMap map(thread, false);
|
|
frame f = thread->last_frame();
|
|
while ( f.id() != thread->must_deopt_id() && ! f.is_first_frame()) {
|
|
f = f.sender(&map);
|
|
}
|
|
if (f.id() == thread->must_deopt_id()) {
|
|
thread->clear_must_deopt_id();
|
|
f.deoptimize(thread);
|
|
} else {
|
|
fatal("missed deoptimization!");
|
|
}
|
|
}
|
|
}
|
|
|
|
// Slow path when the native==>VM/Java barriers detect a safepoint is in
|
|
// progress or when _suspend_flags is non-zero.
|
|
// Current thread needs to self-suspend if there is a suspend request and/or
|
|
// block if a safepoint is in progress.
|
|
// Also check for pending async exception (not including unsafe access error).
|
|
// Note only the native==>VM/Java barriers can call this function and when
|
|
// thread state is _thread_in_native_trans.
|
|
void JavaThread::check_special_condition_for_native_trans(JavaThread *thread) {
|
|
check_safepoint_and_suspend_for_native_trans(thread);
|
|
|
|
if (thread->has_async_exception()) {
|
|
// We are in _thread_in_native_trans state, don't handle unsafe
|
|
// access error since that may block.
|
|
thread->check_and_handle_async_exceptions(false);
|
|
}
|
|
}
|
|
|
|
// This is a variant of the normal
|
|
// check_special_condition_for_native_trans with slightly different
|
|
// semantics for use by critical native wrappers. It does all the
|
|
// normal checks but also performs the transition back into
|
|
// thread_in_Java state. This is required so that critical natives
|
|
// can potentially block and perform a GC if they are the last thread
|
|
// exiting the GC_locker.
|
|
void JavaThread::check_special_condition_for_native_trans_and_transition(JavaThread *thread) {
|
|
check_special_condition_for_native_trans(thread);
|
|
|
|
// Finish the transition
|
|
thread->set_thread_state(_thread_in_Java);
|
|
|
|
if (thread->do_critical_native_unlock()) {
|
|
ThreadInVMfromJavaNoAsyncException tiv(thread);
|
|
GC_locker::unlock_critical(thread);
|
|
thread->clear_critical_native_unlock();
|
|
}
|
|
}
|
|
|
|
// We need to guarantee the Threads_lock here, since resumes are not
|
|
// allowed during safepoint synchronization
|
|
// Can only resume from an external suspension
|
|
void JavaThread::java_resume() {
|
|
assert_locked_or_safepoint(Threads_lock);
|
|
|
|
// Sanity check: thread is gone, has started exiting or the thread
|
|
// was not externally suspended.
|
|
if (!Threads::includes(this) || is_exiting() || !is_external_suspend()) {
|
|
return;
|
|
}
|
|
|
|
MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
|
|
clear_external_suspend();
|
|
|
|
if (is_ext_suspended()) {
|
|
clear_ext_suspended();
|
|
SR_lock()->notify_all();
|
|
}
|
|
}
|
|
|
|
void JavaThread::create_stack_guard_pages() {
|
|
if (! os::uses_stack_guard_pages() || _stack_guard_state != stack_guard_unused) return;
|
|
address low_addr = stack_base() - stack_size();
|
|
size_t len = (StackYellowPages + StackRedPages) * os::vm_page_size();
|
|
|
|
int allocate = os::allocate_stack_guard_pages();
|
|
// warning("Guarding at " PTR_FORMAT " for len " SIZE_FORMAT "\n", low_addr, len);
|
|
|
|
if (allocate && !os::create_stack_guard_pages((char *) low_addr, len)) {
|
|
warning("Attempt to allocate stack guard pages failed.");
|
|
return;
|
|
}
|
|
|
|
if (os::guard_memory((char *) low_addr, len)) {
|
|
_stack_guard_state = stack_guard_enabled;
|
|
} else {
|
|
warning("Attempt to protect stack guard pages failed.");
|
|
if (os::uncommit_memory((char *) low_addr, len)) {
|
|
warning("Attempt to deallocate stack guard pages failed.");
|
|
}
|
|
}
|
|
}
|
|
|
|
void JavaThread::remove_stack_guard_pages() {
|
|
assert(Thread::current() == this, "from different thread");
|
|
if (_stack_guard_state == stack_guard_unused) return;
|
|
address low_addr = stack_base() - stack_size();
|
|
size_t len = (StackYellowPages + StackRedPages) * os::vm_page_size();
|
|
|
|
if (os::allocate_stack_guard_pages()) {
|
|
if (os::remove_stack_guard_pages((char *) low_addr, len)) {
|
|
_stack_guard_state = stack_guard_unused;
|
|
} else {
|
|
warning("Attempt to deallocate stack guard pages failed.");
|
|
}
|
|
} else {
|
|
if (_stack_guard_state == stack_guard_unused) return;
|
|
if (os::unguard_memory((char *) low_addr, len)) {
|
|
_stack_guard_state = stack_guard_unused;
|
|
} else {
|
|
warning("Attempt to unprotect stack guard pages failed.");
|
|
}
|
|
}
|
|
}
|
|
|
|
void JavaThread::enable_stack_yellow_zone() {
|
|
assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
assert(_stack_guard_state != stack_guard_enabled, "already enabled");
|
|
|
|
// The base notation is from the stacks point of view, growing downward.
|
|
// We need to adjust it to work correctly with guard_memory()
|
|
address base = stack_yellow_zone_base() - stack_yellow_zone_size();
|
|
|
|
guarantee(base < stack_base(),"Error calculating stack yellow zone");
|
|
guarantee(base < os::current_stack_pointer(),"Error calculating stack yellow zone");
|
|
|
|
if (os::guard_memory((char *) base, stack_yellow_zone_size())) {
|
|
_stack_guard_state = stack_guard_enabled;
|
|
} else {
|
|
warning("Attempt to guard stack yellow zone failed.");
|
|
}
|
|
enable_register_stack_guard();
|
|
}
|
|
|
|
void JavaThread::disable_stack_yellow_zone() {
|
|
assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
assert(_stack_guard_state != stack_guard_yellow_disabled, "already disabled");
|
|
|
|
// Simply return if called for a thread that does not use guard pages.
|
|
if (_stack_guard_state == stack_guard_unused) return;
|
|
|
|
// The base notation is from the stacks point of view, growing downward.
|
|
// We need to adjust it to work correctly with guard_memory()
|
|
address base = stack_yellow_zone_base() - stack_yellow_zone_size();
|
|
|
|
if (os::unguard_memory((char *)base, stack_yellow_zone_size())) {
|
|
_stack_guard_state = stack_guard_yellow_disabled;
|
|
} else {
|
|
warning("Attempt to unguard stack yellow zone failed.");
|
|
}
|
|
disable_register_stack_guard();
|
|
}
|
|
|
|
void JavaThread::enable_stack_red_zone() {
|
|
// The base notation is from the stacks point of view, growing downward.
|
|
// We need to adjust it to work correctly with guard_memory()
|
|
assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
address base = stack_red_zone_base() - stack_red_zone_size();
|
|
|
|
guarantee(base < stack_base(),"Error calculating stack red zone");
|
|
guarantee(base < os::current_stack_pointer(),"Error calculating stack red zone");
|
|
|
|
if(!os::guard_memory((char *) base, stack_red_zone_size())) {
|
|
warning("Attempt to guard stack red zone failed.");
|
|
}
|
|
}
|
|
|
|
void JavaThread::disable_stack_red_zone() {
|
|
// The base notation is from the stacks point of view, growing downward.
|
|
// We need to adjust it to work correctly with guard_memory()
|
|
assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
address base = stack_red_zone_base() - stack_red_zone_size();
|
|
if (!os::unguard_memory((char *)base, stack_red_zone_size())) {
|
|
warning("Attempt to unguard stack red zone failed.");
|
|
}
|
|
}
|
|
|
|
void JavaThread::frames_do(void f(frame*, const RegisterMap* map)) {
|
|
// ignore is there is no stack
|
|
if (!has_last_Java_frame()) return;
|
|
// traverse the stack frames. Starts from top frame.
|
|
for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
frame* fr = fst.current();
|
|
f(fr, fst.register_map());
|
|
}
|
|
}
|
|
|
|
|
|
#ifndef PRODUCT
|
|
// Deoptimization
|
|
// Function for testing deoptimization
|
|
void JavaThread::deoptimize() {
|
|
// BiasedLocking needs an updated RegisterMap for the revoke monitors pass
|
|
StackFrameStream fst(this, UseBiasedLocking);
|
|
bool deopt = false; // Dump stack only if a deopt actually happens.
|
|
bool only_at = strlen(DeoptimizeOnlyAt) > 0;
|
|
// Iterate over all frames in the thread and deoptimize
|
|
for(; !fst.is_done(); fst.next()) {
|
|
if(fst.current()->can_be_deoptimized()) {
|
|
|
|
if (only_at) {
|
|
// Deoptimize only at particular bcis. DeoptimizeOnlyAt
|
|
// consists of comma or carriage return separated numbers so
|
|
// search for the current bci in that string.
|
|
address pc = fst.current()->pc();
|
|
nmethod* nm = (nmethod*) fst.current()->cb();
|
|
ScopeDesc* sd = nm->scope_desc_at( pc);
|
|
char buffer[8];
|
|
jio_snprintf(buffer, sizeof(buffer), "%d", sd->bci());
|
|
size_t len = strlen(buffer);
|
|
const char * found = strstr(DeoptimizeOnlyAt, buffer);
|
|
while (found != NULL) {
|
|
if ((found[len] == ',' || found[len] == '\n' || found[len] == '\0') &&
|
|
(found == DeoptimizeOnlyAt || found[-1] == ',' || found[-1] == '\n')) {
|
|
// Check that the bci found is bracketed by terminators.
|
|
break;
|
|
}
|
|
found = strstr(found + 1, buffer);
|
|
}
|
|
if (!found) {
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (DebugDeoptimization && !deopt) {
|
|
deopt = true; // One-time only print before deopt
|
|
tty->print_cr("[BEFORE Deoptimization]");
|
|
trace_frames();
|
|
trace_stack();
|
|
}
|
|
Deoptimization::deoptimize(this, *fst.current(), fst.register_map());
|
|
}
|
|
}
|
|
|
|
if (DebugDeoptimization && deopt) {
|
|
tty->print_cr("[AFTER Deoptimization]");
|
|
trace_frames();
|
|
}
|
|
}
|
|
|
|
|
|
// Make zombies
|
|
void JavaThread::make_zombies() {
|
|
for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
if (fst.current()->can_be_deoptimized()) {
|
|
// it is a Java nmethod
|
|
nmethod* nm = CodeCache::find_nmethod(fst.current()->pc());
|
|
nm->make_not_entrant();
|
|
}
|
|
}
|
|
}
|
|
#endif // PRODUCT
|
|
|
|
|
|
void JavaThread::deoptimized_wrt_marked_nmethods() {
|
|
if (!has_last_Java_frame()) return;
|
|
// BiasedLocking needs an updated RegisterMap for the revoke monitors pass
|
|
StackFrameStream fst(this, UseBiasedLocking);
|
|
for(; !fst.is_done(); fst.next()) {
|
|
if (fst.current()->should_be_deoptimized()) {
|
|
if (LogCompilation && xtty != NULL) {
|
|
nmethod* nm = fst.current()->cb()->as_nmethod_or_null();
|
|
xtty->elem("deoptimized thread='" UINTX_FORMAT "' compile_id='%d'",
|
|
this->name(), nm != NULL ? nm->compile_id() : -1);
|
|
}
|
|
|
|
Deoptimization::deoptimize(this, *fst.current(), fst.register_map());
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// GC support
|
|
static void frame_gc_epilogue(frame* f, const RegisterMap* map) { f->gc_epilogue(); }
|
|
|
|
void JavaThread::gc_epilogue() {
|
|
frames_do(frame_gc_epilogue);
|
|
}
|
|
|
|
|
|
static void frame_gc_prologue(frame* f, const RegisterMap* map) { f->gc_prologue(); }
|
|
|
|
void JavaThread::gc_prologue() {
|
|
frames_do(frame_gc_prologue);
|
|
}
|
|
|
|
// If the caller is a NamedThread, then remember, in the current scope,
|
|
// the given JavaThread in its _processed_thread field.
|
|
class RememberProcessedThread: public StackObj {
|
|
NamedThread* _cur_thr;
|
|
public:
|
|
RememberProcessedThread(JavaThread* jthr) {
|
|
Thread* thread = Thread::current();
|
|
if (thread->is_Named_thread()) {
|
|
_cur_thr = (NamedThread *)thread;
|
|
_cur_thr->set_processed_thread(jthr);
|
|
} else {
|
|
_cur_thr = NULL;
|
|
}
|
|
}
|
|
|
|
~RememberProcessedThread() {
|
|
if (_cur_thr) {
|
|
_cur_thr->set_processed_thread(NULL);
|
|
}
|
|
}
|
|
};
|
|
|
|
void JavaThread::oops_do(OopClosure* f, CLDToOopClosure* cld_f, CodeBlobClosure* cf) {
|
|
// Verify that the deferred card marks have been flushed.
|
|
assert(deferred_card_mark().is_empty(), "Should be empty during GC");
|
|
|
|
// The ThreadProfiler oops_do is done from FlatProfiler::oops_do
|
|
// since there may be more than one thread using each ThreadProfiler.
|
|
|
|
// Traverse the GCHandles
|
|
Thread::oops_do(f, cld_f, cf);
|
|
|
|
assert( (!has_last_Java_frame() && java_call_counter() == 0) ||
|
|
(has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
|
|
|
|
if (has_last_Java_frame()) {
|
|
// Record JavaThread to GC thread
|
|
RememberProcessedThread rpt(this);
|
|
|
|
// Traverse the privileged stack
|
|
if (_privileged_stack_top != NULL) {
|
|
_privileged_stack_top->oops_do(f);
|
|
}
|
|
|
|
// traverse the registered growable array
|
|
if (_array_for_gc != NULL) {
|
|
for (int index = 0; index < _array_for_gc->length(); index++) {
|
|
f->do_oop(_array_for_gc->adr_at(index));
|
|
}
|
|
}
|
|
|
|
// Traverse the monitor chunks
|
|
for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) {
|
|
chunk->oops_do(f);
|
|
}
|
|
|
|
// Traverse the execution stack
|
|
for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
fst.current()->oops_do(f, cld_f, cf, fst.register_map());
|
|
}
|
|
}
|
|
|
|
// callee_target is never live across a gc point so NULL it here should
|
|
// it still contain a methdOop.
|
|
|
|
set_callee_target(NULL);
|
|
|
|
assert(vframe_array_head() == NULL, "deopt in progress at a safepoint!");
|
|
// If we have deferred set_locals there might be oops waiting to be
|
|
// written
|
|
GrowableArray<jvmtiDeferredLocalVariableSet*>* list = deferred_locals();
|
|
if (list != NULL) {
|
|
for (int i = 0; i < list->length(); i++) {
|
|
list->at(i)->oops_do(f);
|
|
}
|
|
}
|
|
|
|
// Traverse instance variables at the end since the GC may be moving things
|
|
// around using this function
|
|
f->do_oop((oop*) &_threadObj);
|
|
f->do_oop((oop*) &_vm_result);
|
|
f->do_oop((oop*) &_exception_oop);
|
|
f->do_oop((oop*) &_pending_async_exception);
|
|
|
|
if (jvmti_thread_state() != NULL) {
|
|
jvmti_thread_state()->oops_do(f);
|
|
}
|
|
}
|
|
|
|
void JavaThread::nmethods_do(CodeBlobClosure* cf) {
|
|
Thread::nmethods_do(cf); // (super method is a no-op)
|
|
|
|
assert( (!has_last_Java_frame() && java_call_counter() == 0) ||
|
|
(has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
|
|
|
|
if (has_last_Java_frame()) {
|
|
// Traverse the execution stack
|
|
for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
fst.current()->nmethods_do(cf);
|
|
}
|
|
}
|
|
}
|
|
|
|
void JavaThread::metadata_do(void f(Metadata*)) {
|
|
Thread::metadata_do(f);
|
|
if (has_last_Java_frame()) {
|
|
// Traverse the execution stack to call f() on the methods in the stack
|
|
for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
fst.current()->metadata_do(f);
|
|
}
|
|
} else if (is_Compiler_thread()) {
|
|
// need to walk ciMetadata in current compile tasks to keep alive.
|
|
CompilerThread* ct = (CompilerThread*)this;
|
|
if (ct->env() != NULL) {
|
|
ct->env()->metadata_do(f);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Printing
|
|
const char* _get_thread_state_name(JavaThreadState _thread_state) {
|
|
switch (_thread_state) {
|
|
case _thread_uninitialized: return "_thread_uninitialized";
|
|
case _thread_new: return "_thread_new";
|
|
case _thread_new_trans: return "_thread_new_trans";
|
|
case _thread_in_native: return "_thread_in_native";
|
|
case _thread_in_native_trans: return "_thread_in_native_trans";
|
|
case _thread_in_vm: return "_thread_in_vm";
|
|
case _thread_in_vm_trans: return "_thread_in_vm_trans";
|
|
case _thread_in_Java: return "_thread_in_Java";
|
|
case _thread_in_Java_trans: return "_thread_in_Java_trans";
|
|
case _thread_blocked: return "_thread_blocked";
|
|
case _thread_blocked_trans: return "_thread_blocked_trans";
|
|
default: return "unknown thread state";
|
|
}
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
void JavaThread::print_thread_state_on(outputStream *st) const {
|
|
st->print_cr(" JavaThread state: %s", _get_thread_state_name(_thread_state));
|
|
};
|
|
void JavaThread::print_thread_state() const {
|
|
print_thread_state_on(tty);
|
|
};
|
|
#endif // PRODUCT
|
|
|
|
// Called by Threads::print() for VM_PrintThreads operation
|
|
void JavaThread::print_on(outputStream *st) const {
|
|
st->print("\"%s\" ", get_thread_name());
|
|
oop thread_oop = threadObj();
|
|
if (thread_oop != NULL) {
|
|
st->print("#" INT64_FORMAT " ", java_lang_Thread::thread_id(thread_oop));
|
|
if (java_lang_Thread::is_daemon(thread_oop)) st->print("daemon ");
|
|
st->print("prio=%d ", java_lang_Thread::priority(thread_oop));
|
|
}
|
|
Thread::print_on(st);
|
|
// print guess for valid stack memory region (assume 4K pages); helps lock debugging
|
|
st->print_cr("[" INTPTR_FORMAT "]", (intptr_t)last_Java_sp() & ~right_n_bits(12));
|
|
if (thread_oop != NULL && JDK_Version::is_gte_jdk15x_version()) {
|
|
st->print_cr(" java.lang.Thread.State: %s", java_lang_Thread::thread_status_name(thread_oop));
|
|
}
|
|
#ifndef PRODUCT
|
|
print_thread_state_on(st);
|
|
_safepoint_state->print_on(st);
|
|
#endif // PRODUCT
|
|
}
|
|
|
|
// Called by fatal error handler. The difference between this and
|
|
// JavaThread::print() is that we can't grab lock or allocate memory.
|
|
void JavaThread::print_on_error(outputStream* st, char *buf, int buflen) const {
|
|
st->print("JavaThread \"%s\"", get_thread_name_string(buf, buflen));
|
|
oop thread_obj = threadObj();
|
|
if (thread_obj != NULL) {
|
|
if (java_lang_Thread::is_daemon(thread_obj)) st->print(" daemon");
|
|
}
|
|
st->print(" [");
|
|
st->print("%s", _get_thread_state_name(_thread_state));
|
|
if (osthread()) {
|
|
st->print(", id=%d", osthread()->thread_id());
|
|
}
|
|
st->print(", stack(" PTR_FORMAT "," PTR_FORMAT ")",
|
|
_stack_base - _stack_size, _stack_base);
|
|
st->print("]");
|
|
return;
|
|
}
|
|
|
|
// Verification
|
|
|
|
static void frame_verify(frame* f, const RegisterMap *map) { f->verify(map); }
|
|
|
|
void JavaThread::verify() {
|
|
// Verify oops in the thread.
|
|
oops_do(&VerifyOopClosure::verify_oop, NULL, NULL);
|
|
|
|
// Verify the stack frames.
|
|
frames_do(frame_verify);
|
|
}
|
|
|
|
// CR 6300358 (sub-CR 2137150)
|
|
// Most callers of this method assume that it can't return NULL but a
|
|
// thread may not have a name whilst it is in the process of attaching to
|
|
// the VM - see CR 6412693, and there are places where a JavaThread can be
|
|
// seen prior to having it's threadObj set (eg JNI attaching threads and
|
|
// if vm exit occurs during initialization). These cases can all be accounted
|
|
// for such that this method never returns NULL.
|
|
const char* JavaThread::get_thread_name() const {
|
|
#ifdef ASSERT
|
|
// early safepoints can hit while current thread does not yet have TLS
|
|
if (!SafepointSynchronize::is_at_safepoint()) {
|
|
Thread *cur = Thread::current();
|
|
if (!(cur->is_Java_thread() && cur == this)) {
|
|
// Current JavaThreads are allowed to get their own name without
|
|
// the Threads_lock.
|
|
assert_locked_or_safepoint(Threads_lock);
|
|
}
|
|
}
|
|
#endif // ASSERT
|
|
return get_thread_name_string();
|
|
}
|
|
|
|
// Returns a non-NULL representation of this thread's name, or a suitable
|
|
// descriptive string if there is no set name
|
|
const char* JavaThread::get_thread_name_string(char* buf, int buflen) const {
|
|
const char* name_str;
|
|
oop thread_obj = threadObj();
|
|
if (thread_obj != NULL) {
|
|
typeArrayOop name = java_lang_Thread::name(thread_obj);
|
|
if (name != NULL) {
|
|
if (buf == NULL) {
|
|
name_str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
|
|
}
|
|
else {
|
|
name_str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length(), buf, buflen);
|
|
}
|
|
}
|
|
else if (is_attaching_via_jni()) { // workaround for 6412693 - see 6404306
|
|
name_str = "<no-name - thread is attaching>";
|
|
}
|
|
else {
|
|
name_str = Thread::name();
|
|
}
|
|
}
|
|
else {
|
|
name_str = Thread::name();
|
|
}
|
|
assert(name_str != NULL, "unexpected NULL thread name");
|
|
return name_str;
|
|
}
|
|
|
|
|
|
const char* JavaThread::get_threadgroup_name() const {
|
|
debug_only(if (JavaThread::current() != this) assert_locked_or_safepoint(Threads_lock);)
|
|
oop thread_obj = threadObj();
|
|
if (thread_obj != NULL) {
|
|
oop thread_group = java_lang_Thread::threadGroup(thread_obj);
|
|
if (thread_group != NULL) {
|
|
typeArrayOop name = java_lang_ThreadGroup::name(thread_group);
|
|
// ThreadGroup.name can be null
|
|
if (name != NULL) {
|
|
const char* str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
|
|
return str;
|
|
}
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
const char* JavaThread::get_parent_name() const {
|
|
debug_only(if (JavaThread::current() != this) assert_locked_or_safepoint(Threads_lock);)
|
|
oop thread_obj = threadObj();
|
|
if (thread_obj != NULL) {
|
|
oop thread_group = java_lang_Thread::threadGroup(thread_obj);
|
|
if (thread_group != NULL) {
|
|
oop parent = java_lang_ThreadGroup::parent(thread_group);
|
|
if (parent != NULL) {
|
|
typeArrayOop name = java_lang_ThreadGroup::name(parent);
|
|
// ThreadGroup.name can be null
|
|
if (name != NULL) {
|
|
const char* str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
|
|
return str;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
ThreadPriority JavaThread::java_priority() const {
|
|
oop thr_oop = threadObj();
|
|
if (thr_oop == NULL) return NormPriority; // Bootstrapping
|
|
ThreadPriority priority = java_lang_Thread::priority(thr_oop);
|
|
assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
|
|
return priority;
|
|
}
|
|
|
|
void JavaThread::prepare(jobject jni_thread, ThreadPriority prio) {
|
|
|
|
assert(Threads_lock->owner() == Thread::current(), "must have threads lock");
|
|
// Link Java Thread object <-> C++ Thread
|
|
|
|
// Get the C++ thread object (an oop) from the JNI handle (a jthread)
|
|
// and put it into a new Handle. The Handle "thread_oop" can then
|
|
// be used to pass the C++ thread object to other methods.
|
|
|
|
// Set the Java level thread object (jthread) field of the
|
|
// new thread (a JavaThread *) to C++ thread object using the
|
|
// "thread_oop" handle.
|
|
|
|
// Set the thread field (a JavaThread *) of the
|
|
// oop representing the java_lang_Thread to the new thread (a JavaThread *).
|
|
|
|
Handle thread_oop(Thread::current(),
|
|
JNIHandles::resolve_non_null(jni_thread));
|
|
assert(InstanceKlass::cast(thread_oop->klass())->is_linked(),
|
|
"must be initialized");
|
|
set_threadObj(thread_oop());
|
|
java_lang_Thread::set_thread(thread_oop(), this);
|
|
|
|
if (prio == NoPriority) {
|
|
prio = java_lang_Thread::priority(thread_oop());
|
|
assert(prio != NoPriority, "A valid priority should be present");
|
|
}
|
|
|
|
// Push the Java priority down to the native thread; needs Threads_lock
|
|
Thread::set_priority(this, prio);
|
|
|
|
// Add the new thread to the Threads list and set it in motion.
|
|
// We must have threads lock in order to call Threads::add.
|
|
// It is crucial that we do not block before the thread is
|
|
// added to the Threads list for if a GC happens, then the java_thread oop
|
|
// will not be visited by GC.
|
|
Threads::add(this);
|
|
}
|
|
|
|
oop JavaThread::current_park_blocker() {
|
|
// Support for JSR-166 locks
|
|
oop thread_oop = threadObj();
|
|
if (thread_oop != NULL &&
|
|
JDK_Version::current().supports_thread_park_blocker()) {
|
|
return java_lang_Thread::park_blocker(thread_oop);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
|
|
void JavaThread::print_stack_on(outputStream* st) {
|
|
if (!has_last_Java_frame()) return;
|
|
ResourceMark rm;
|
|
HandleMark hm;
|
|
|
|
RegisterMap reg_map(this);
|
|
vframe* start_vf = last_java_vframe(®_map);
|
|
int count = 0;
|
|
for (vframe* f = start_vf; f; f = f->sender() ) {
|
|
if (f->is_java_frame()) {
|
|
javaVFrame* jvf = javaVFrame::cast(f);
|
|
java_lang_Throwable::print_stack_element(st, jvf->method(), jvf->bci());
|
|
|
|
// Print out lock information
|
|
if (JavaMonitorsInStackTrace) {
|
|
jvf->print_lock_info_on(st, count);
|
|
}
|
|
} else {
|
|
// Ignore non-Java frames
|
|
}
|
|
|
|
// Bail-out case for too deep stacks
|
|
count++;
|
|
if (MaxJavaStackTraceDepth == count) return;
|
|
}
|
|
}
|
|
|
|
|
|
// JVMTI PopFrame support
|
|
void JavaThread::popframe_preserve_args(ByteSize size_in_bytes, void* start) {
|
|
assert(_popframe_preserved_args == NULL, "should not wipe out old PopFrame preserved arguments");
|
|
if (in_bytes(size_in_bytes) != 0) {
|
|
_popframe_preserved_args = NEW_C_HEAP_ARRAY(char, in_bytes(size_in_bytes), mtThread);
|
|
_popframe_preserved_args_size = in_bytes(size_in_bytes);
|
|
Copy::conjoint_jbytes(start, _popframe_preserved_args, _popframe_preserved_args_size);
|
|
}
|
|
}
|
|
|
|
void* JavaThread::popframe_preserved_args() {
|
|
return _popframe_preserved_args;
|
|
}
|
|
|
|
ByteSize JavaThread::popframe_preserved_args_size() {
|
|
return in_ByteSize(_popframe_preserved_args_size);
|
|
}
|
|
|
|
WordSize JavaThread::popframe_preserved_args_size_in_words() {
|
|
int sz = in_bytes(popframe_preserved_args_size());
|
|
assert(sz % wordSize == 0, "argument size must be multiple of wordSize");
|
|
return in_WordSize(sz / wordSize);
|
|
}
|
|
|
|
void JavaThread::popframe_free_preserved_args() {
|
|
assert(_popframe_preserved_args != NULL, "should not free PopFrame preserved arguments twice");
|
|
FREE_C_HEAP_ARRAY(char, (char*) _popframe_preserved_args, mtThread);
|
|
_popframe_preserved_args = NULL;
|
|
_popframe_preserved_args_size = 0;
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
|
|
void JavaThread::trace_frames() {
|
|
tty->print_cr("[Describe stack]");
|
|
int frame_no = 1;
|
|
for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
tty->print(" %d. ", frame_no++);
|
|
fst.current()->print_value_on(tty,this);
|
|
tty->cr();
|
|
}
|
|
}
|
|
|
|
class PrintAndVerifyOopClosure: public OopClosure {
|
|
protected:
|
|
template <class T> inline void do_oop_work(T* p) {
|
|
oop obj = oopDesc::load_decode_heap_oop(p);
|
|
if (obj == NULL) return;
|
|
tty->print(INTPTR_FORMAT ": ", p);
|
|
if (obj->is_oop_or_null()) {
|
|
if (obj->is_objArray()) {
|
|
tty->print_cr("valid objArray: " INTPTR_FORMAT, (oopDesc*) obj);
|
|
} else {
|
|
obj->print();
|
|
}
|
|
} else {
|
|
tty->print_cr("invalid oop: " INTPTR_FORMAT, (oopDesc*) obj);
|
|
}
|
|
tty->cr();
|
|
}
|
|
public:
|
|
virtual void do_oop(oop* p) { do_oop_work(p); }
|
|
virtual void do_oop(narrowOop* p) { do_oop_work(p); }
|
|
};
|
|
|
|
|
|
static void oops_print(frame* f, const RegisterMap *map) {
|
|
PrintAndVerifyOopClosure print;
|
|
f->print_value();
|
|
f->oops_do(&print, NULL, NULL, (RegisterMap*)map);
|
|
}
|
|
|
|
// Print our all the locations that contain oops and whether they are
|
|
// valid or not. This useful when trying to find the oldest frame
|
|
// where an oop has gone bad since the frame walk is from youngest to
|
|
// oldest.
|
|
void JavaThread::trace_oops() {
|
|
tty->print_cr("[Trace oops]");
|
|
frames_do(oops_print);
|
|
}
|
|
|
|
|
|
#ifdef ASSERT
|
|
// Print or validate the layout of stack frames
|
|
void JavaThread::print_frame_layout(int depth, bool validate_only) {
|
|
ResourceMark rm;
|
|
PRESERVE_EXCEPTION_MARK;
|
|
FrameValues values;
|
|
int frame_no = 0;
|
|
for(StackFrameStream fst(this, false); !fst.is_done(); fst.next()) {
|
|
fst.current()->describe(values, ++frame_no);
|
|
if (depth == frame_no) break;
|
|
}
|
|
if (validate_only) {
|
|
values.validate();
|
|
} else {
|
|
tty->print_cr("[Describe stack layout]");
|
|
values.print(this);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
void JavaThread::trace_stack_from(vframe* start_vf) {
|
|
ResourceMark rm;
|
|
int vframe_no = 1;
|
|
for (vframe* f = start_vf; f; f = f->sender() ) {
|
|
if (f->is_java_frame()) {
|
|
javaVFrame::cast(f)->print_activation(vframe_no++);
|
|
} else {
|
|
f->print();
|
|
}
|
|
if (vframe_no > StackPrintLimit) {
|
|
tty->print_cr("...<more frames>...");
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void JavaThread::trace_stack() {
|
|
if (!has_last_Java_frame()) return;
|
|
ResourceMark rm;
|
|
HandleMark hm;
|
|
RegisterMap reg_map(this);
|
|
trace_stack_from(last_java_vframe(®_map));
|
|
}
|
|
|
|
|
|
#endif // PRODUCT
|
|
|
|
|
|
javaVFrame* JavaThread::last_java_vframe(RegisterMap *reg_map) {
|
|
assert(reg_map != NULL, "a map must be given");
|
|
frame f = last_frame();
|
|
for (vframe* vf = vframe::new_vframe(&f, reg_map, this); vf; vf = vf->sender() ) {
|
|
if (vf->is_java_frame()) return javaVFrame::cast(vf);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
|
|
Klass* JavaThread::security_get_caller_class(int depth) {
|
|
vframeStream vfst(this);
|
|
vfst.security_get_caller_frame(depth);
|
|
if (!vfst.at_end()) {
|
|
return vfst.method()->method_holder();
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static void compiler_thread_entry(JavaThread* thread, TRAPS) {
|
|
assert(thread->is_Compiler_thread(), "must be compiler thread");
|
|
CompileBroker::compiler_thread_loop();
|
|
}
|
|
|
|
// Create a CompilerThread
|
|
CompilerThread::CompilerThread(CompileQueue* queue, CompilerCounters* counters)
|
|
: JavaThread(&compiler_thread_entry) {
|
|
_env = NULL;
|
|
_log = NULL;
|
|
_task = NULL;
|
|
_queue = queue;
|
|
_counters = counters;
|
|
_buffer_blob = NULL;
|
|
_scanned_nmethod = NULL;
|
|
_compiler = NULL;
|
|
|
|
#ifndef PRODUCT
|
|
_ideal_graph_printer = NULL;
|
|
#endif
|
|
}
|
|
|
|
void CompilerThread::oops_do(OopClosure* f, CLDToOopClosure* cld_f, CodeBlobClosure* cf) {
|
|
JavaThread::oops_do(f, cld_f, cf);
|
|
if (_scanned_nmethod != NULL && cf != NULL) {
|
|
// Safepoints can occur when the sweeper is scanning an nmethod so
|
|
// process it here to make sure it isn't unloaded in the middle of
|
|
// a scan.
|
|
cf->do_code_blob(_scanned_nmethod);
|
|
}
|
|
}
|
|
|
|
|
|
// ======= Threads ========
|
|
|
|
// The Threads class links together all active threads, and provides
|
|
// operations over all threads. It is protected by its own Mutex
|
|
// lock, which is also used in other contexts to protect thread
|
|
// operations from having the thread being operated on from exiting
|
|
// and going away unexpectedly (e.g., safepoint synchronization)
|
|
|
|
JavaThread* Threads::_thread_list = NULL;
|
|
int Threads::_number_of_threads = 0;
|
|
int Threads::_number_of_non_daemon_threads = 0;
|
|
int Threads::_return_code = 0;
|
|
size_t JavaThread::_stack_size_at_create = 0;
|
|
#ifdef ASSERT
|
|
bool Threads::_vm_complete = false;
|
|
#endif
|
|
|
|
// All JavaThreads
|
|
#define ALL_JAVA_THREADS(X) for (JavaThread* X = _thread_list; X; X = X->next())
|
|
|
|
// All JavaThreads + all non-JavaThreads (i.e., every thread in the system)
|
|
void Threads::threads_do(ThreadClosure* tc) {
|
|
assert_locked_or_safepoint(Threads_lock);
|
|
// ALL_JAVA_THREADS iterates through all JavaThreads
|
|
ALL_JAVA_THREADS(p) {
|
|
tc->do_thread(p);
|
|
}
|
|
// Someday we could have a table or list of all non-JavaThreads.
|
|
// For now, just manually iterate through them.
|
|
tc->do_thread(VMThread::vm_thread());
|
|
Universe::heap()->gc_threads_do(tc);
|
|
WatcherThread *wt = WatcherThread::watcher_thread();
|
|
// Strictly speaking, the following NULL check isn't sufficient to make sure
|
|
// the data for WatcherThread is still valid upon being examined. However,
|
|
// considering that WatchThread terminates when the VM is on the way to
|
|
// exit at safepoint, the chance of the above is extremely small. The right
|
|
// way to prevent termination of WatcherThread would be to acquire
|
|
// Terminator_lock, but we can't do that without violating the lock rank
|
|
// checking in some cases.
|
|
if (wt != NULL)
|
|
tc->do_thread(wt);
|
|
|
|
// If CompilerThreads ever become non-JavaThreads, add them here
|
|
}
|
|
|
|
jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
|
|
|
|
extern void JDK_Version_init();
|
|
|
|
// Check version
|
|
if (!is_supported_jni_version(args->version)) return JNI_EVERSION;
|
|
|
|
// Initialize the output stream module
|
|
ostream_init();
|
|
|
|
// Process java launcher properties.
|
|
Arguments::process_sun_java_launcher_properties(args);
|
|
|
|
// Initialize the os module before using TLS
|
|
os::init();
|
|
|
|
// Initialize system properties.
|
|
Arguments::init_system_properties();
|
|
|
|
// So that JDK version can be used as a discrimintor when parsing arguments
|
|
JDK_Version_init();
|
|
|
|
// Update/Initialize System properties after JDK version number is known
|
|
Arguments::init_version_specific_system_properties();
|
|
|
|
// Parse arguments
|
|
jint parse_result = Arguments::parse(args);
|
|
if (parse_result != JNI_OK) return parse_result;
|
|
|
|
os::init_before_ergo();
|
|
|
|
jint ergo_result = Arguments::apply_ergo();
|
|
if (ergo_result != JNI_OK) return ergo_result;
|
|
|
|
if (PauseAtStartup) {
|
|
os::pause();
|
|
}
|
|
|
|
#ifndef USDT2
|
|
HS_DTRACE_PROBE(hotspot, vm__init__begin);
|
|
#else /* USDT2 */
|
|
HOTSPOT_VM_INIT_BEGIN();
|
|
#endif /* USDT2 */
|
|
|
|
// Record VM creation timing statistics
|
|
TraceVmCreationTime create_vm_timer;
|
|
create_vm_timer.start();
|
|
|
|
// Timing (must come after argument parsing)
|
|
TraceTime timer("Create VM", TraceStartupTime);
|
|
|
|
// Initialize the os module after parsing the args
|
|
jint os_init_2_result = os::init_2();
|
|
if (os_init_2_result != JNI_OK) return os_init_2_result;
|
|
|
|
jint adjust_after_os_result = Arguments::adjust_after_os();
|
|
if (adjust_after_os_result != JNI_OK) return adjust_after_os_result;
|
|
|
|
// intialize TLS
|
|
ThreadLocalStorage::init();
|
|
|
|
// Bootstrap native memory tracking, so it can start recording memory
|
|
// activities before worker thread is started. This is the first phase
|
|
// of bootstrapping, VM is currently running in single-thread mode.
|
|
MemTracker::bootstrap_single_thread();
|
|
|
|
// Initialize output stream logging
|
|
ostream_init_log();
|
|
|
|
// Convert -Xrun to -agentlib: if there is no JVM_OnLoad
|
|
// Must be before create_vm_init_agents()
|
|
if (Arguments::init_libraries_at_startup()) {
|
|
convert_vm_init_libraries_to_agents();
|
|
}
|
|
|
|
// Launch -agentlib/-agentpath and converted -Xrun agents
|
|
if (Arguments::init_agents_at_startup()) {
|
|
create_vm_init_agents();
|
|
}
|
|
|
|
// Initialize Threads state
|
|
_thread_list = NULL;
|
|
_number_of_threads = 0;
|
|
_number_of_non_daemon_threads = 0;
|
|
|
|
// Initialize global data structures and create system classes in heap
|
|
vm_init_globals();
|
|
|
|
// Attach the main thread to this os thread
|
|
JavaThread* main_thread = new JavaThread();
|
|
main_thread->set_thread_state(_thread_in_vm);
|
|
// must do this before set_active_handles and initialize_thread_local_storage
|
|
// Note: on solaris initialize_thread_local_storage() will (indirectly)
|
|
// change the stack size recorded here to one based on the java thread
|
|
// stacksize. This adjusted size is what is used to figure the placement
|
|
// of the guard pages.
|
|
main_thread->record_stack_base_and_size();
|
|
main_thread->initialize_thread_local_storage();
|
|
|
|
main_thread->set_active_handles(JNIHandleBlock::allocate_block());
|
|
|
|
if (!main_thread->set_as_starting_thread()) {
|
|
vm_shutdown_during_initialization(
|
|
"Failed necessary internal allocation. Out of swap space");
|
|
delete main_thread;
|
|
*canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
|
|
return JNI_ENOMEM;
|
|
}
|
|
|
|
// Enable guard page *after* os::create_main_thread(), otherwise it would
|
|
// crash Linux VM, see notes in os_linux.cpp.
|
|
main_thread->create_stack_guard_pages();
|
|
|
|
// Initialize Java-Level synchronization subsystem
|
|
ObjectMonitor::Initialize() ;
|
|
|
|
// Second phase of bootstrapping, VM is about entering multi-thread mode
|
|
MemTracker::bootstrap_multi_thread();
|
|
|
|
// Initialize global modules
|
|
jint status = init_globals();
|
|
if (status != JNI_OK) {
|
|
delete main_thread;
|
|
*canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
|
|
return status;
|
|
}
|
|
|
|
// Should be done after the heap is fully created
|
|
main_thread->cache_global_variables();
|
|
|
|
HandleMark hm;
|
|
|
|
{ MutexLocker mu(Threads_lock);
|
|
Threads::add(main_thread);
|
|
}
|
|
|
|
// Any JVMTI raw monitors entered in onload will transition into
|
|
// real raw monitor. VM is setup enough here for raw monitor enter.
|
|
JvmtiExport::transition_pending_onload_raw_monitors();
|
|
|
|
// Fully start NMT
|
|
MemTracker::start();
|
|
|
|
// Create the VMThread
|
|
{ TraceTime timer("Start VMThread", TraceStartupTime);
|
|
VMThread::create();
|
|
Thread* vmthread = VMThread::vm_thread();
|
|
|
|
if (!os::create_thread(vmthread, os::vm_thread))
|
|
vm_exit_during_initialization("Cannot create VM thread. Out of system resources.");
|
|
|
|
// Wait for the VM thread to become ready, and VMThread::run to initialize
|
|
// Monitors can have spurious returns, must always check another state flag
|
|
{
|
|
MutexLocker ml(Notify_lock);
|
|
os::start_thread(vmthread);
|
|
while (vmthread->active_handles() == NULL) {
|
|
Notify_lock->wait();
|
|
}
|
|
}
|
|
}
|
|
|
|
assert (Universe::is_fully_initialized(), "not initialized");
|
|
if (VerifyDuringStartup) {
|
|
// Make sure we're starting with a clean slate.
|
|
VM_Verify verify_op;
|
|
VMThread::execute(&verify_op);
|
|
}
|
|
|
|
EXCEPTION_MARK;
|
|
|
|
// At this point, the Universe is initialized, but we have not executed
|
|
// any byte code. Now is a good time (the only time) to dump out the
|
|
// internal state of the JVM for sharing.
|
|
if (DumpSharedSpaces) {
|
|
MetaspaceShared::preload_and_dump(CHECK_0);
|
|
ShouldNotReachHere();
|
|
}
|
|
|
|
// Always call even when there are not JVMTI environments yet, since environments
|
|
// may be attached late and JVMTI must track phases of VM execution
|
|
JvmtiExport::enter_start_phase();
|
|
|
|
// Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
|
|
JvmtiExport::post_vm_start();
|
|
|
|
{
|
|
TraceTime timer("Initialize java.lang classes", TraceStartupTime);
|
|
|
|
if (EagerXrunInit && Arguments::init_libraries_at_startup()) {
|
|
create_vm_init_libraries();
|
|
}
|
|
|
|
initialize_class(vmSymbols::java_lang_String(), CHECK_0);
|
|
|
|
// Initialize java_lang.System (needed before creating the thread)
|
|
initialize_class(vmSymbols::java_lang_System(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK_0);
|
|
Handle thread_group = create_initial_thread_group(CHECK_0);
|
|
Universe::set_main_thread_group(thread_group());
|
|
initialize_class(vmSymbols::java_lang_Thread(), CHECK_0);
|
|
oop thread_object = create_initial_thread(thread_group, main_thread, CHECK_0);
|
|
main_thread->set_threadObj(thread_object);
|
|
// Set thread status to running since main thread has
|
|
// been started and running.
|
|
java_lang_Thread::set_thread_status(thread_object,
|
|
java_lang_Thread::RUNNABLE);
|
|
|
|
// The VM creates & returns objects of this class. Make sure it's initialized.
|
|
initialize_class(vmSymbols::java_lang_Class(), CHECK_0);
|
|
|
|
// The VM preresolves methods to these classes. Make sure that they get initialized
|
|
initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK_0);
|
|
call_initializeSystemClass(CHECK_0);
|
|
|
|
// get the Java runtime name after java.lang.System is initialized
|
|
JDK_Version::set_runtime_name(get_java_runtime_name(THREAD));
|
|
JDK_Version::set_runtime_version(get_java_runtime_version(THREAD));
|
|
|
|
// an instance of OutOfMemory exception has been allocated earlier
|
|
initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK_0);
|
|
}
|
|
|
|
// See : bugid 4211085.
|
|
// Background : the static initializer of java.lang.Compiler tries to read
|
|
// property"java.compiler" and read & write property "java.vm.info".
|
|
// When a security manager is installed through the command line
|
|
// option "-Djava.security.manager", the above properties are not
|
|
// readable and the static initializer for java.lang.Compiler fails
|
|
// resulting in a NoClassDefFoundError. This can happen in any
|
|
// user code which calls methods in java.lang.Compiler.
|
|
// Hack : the hack is to pre-load and initialize this class, so that only
|
|
// system domains are on the stack when the properties are read.
|
|
// Currently even the AWT code has calls to methods in java.lang.Compiler.
|
|
// On the classic VM, java.lang.Compiler is loaded very early to load the JIT.
|
|
// Future Fix : the best fix is to grant everyone permissions to read "java.compiler" and
|
|
// read and write"java.vm.info" in the default policy file. See bugid 4211383
|
|
// Once that is done, we should remove this hack.
|
|
initialize_class(vmSymbols::java_lang_Compiler(), CHECK_0);
|
|
|
|
// More hackery - the static initializer of java.lang.Compiler adds the string "nojit" to
|
|
// the java.vm.info property if no jit gets loaded through java.lang.Compiler (the hotspot
|
|
// compiler does not get loaded through java.lang.Compiler). "java -version" with the
|
|
// hotspot vm says "nojit" all the time which is confusing. So, we reset it here.
|
|
// This should also be taken out as soon as 4211383 gets fixed.
|
|
reset_vm_info_property(CHECK_0);
|
|
|
|
quicken_jni_functions();
|
|
|
|
// Must be run after init_ft which initializes ft_enabled
|
|
if (TRACE_INITIALIZE() != JNI_OK) {
|
|
vm_exit_during_initialization("Failed to initialize tracing backend");
|
|
}
|
|
|
|
// Set flag that basic initialization has completed. Used by exceptions and various
|
|
// debug stuff, that does not work until all basic classes have been initialized.
|
|
set_init_completed();
|
|
|
|
#ifndef USDT2
|
|
HS_DTRACE_PROBE(hotspot, vm__init__end);
|
|
#else /* USDT2 */
|
|
HOTSPOT_VM_INIT_END();
|
|
#endif /* USDT2 */
|
|
|
|
// record VM initialization completion time
|
|
#if INCLUDE_MANAGEMENT
|
|
Management::record_vm_init_completed();
|
|
#endif // INCLUDE_MANAGEMENT
|
|
|
|
// Compute system loader. Note that this has to occur after set_init_completed, since
|
|
// valid exceptions may be thrown in the process.
|
|
// Note that we do not use CHECK_0 here since we are inside an EXCEPTION_MARK and
|
|
// set_init_completed has just been called, causing exceptions not to be shortcut
|
|
// anymore. We call vm_exit_during_initialization directly instead.
|
|
SystemDictionary::compute_java_system_loader(THREAD);
|
|
if (HAS_PENDING_EXCEPTION) {
|
|
vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
|
|
}
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
// Support for ConcurrentMarkSweep. This should be cleaned up
|
|
// and better encapsulated. The ugly nested if test would go away
|
|
// once things are properly refactored. XXX YSR
|
|
if (UseConcMarkSweepGC || UseG1GC) {
|
|
if (UseConcMarkSweepGC) {
|
|
ConcurrentMarkSweepThread::makeSurrogateLockerThread(THREAD);
|
|
} else {
|
|
ConcurrentMarkThread::makeSurrogateLockerThread(THREAD);
|
|
}
|
|
if (HAS_PENDING_EXCEPTION) {
|
|
vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
|
|
}
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
// Always call even when there are not JVMTI environments yet, since environments
|
|
// may be attached late and JVMTI must track phases of VM execution
|
|
JvmtiExport::enter_live_phase();
|
|
|
|
// Signal Dispatcher needs to be started before VMInit event is posted
|
|
os::signal_init();
|
|
|
|
// Start Attach Listener if +StartAttachListener or it can't be started lazily
|
|
if (!DisableAttachMechanism) {
|
|
AttachListener::vm_start();
|
|
if (StartAttachListener || AttachListener::init_at_startup()) {
|
|
AttachListener::init();
|
|
}
|
|
}
|
|
|
|
// Launch -Xrun agents
|
|
// Must be done in the JVMTI live phase so that for backward compatibility the JDWP
|
|
// back-end can launch with -Xdebug -Xrunjdwp.
|
|
if (!EagerXrunInit && Arguments::init_libraries_at_startup()) {
|
|
create_vm_init_libraries();
|
|
}
|
|
|
|
// Notify JVMTI agents that VM initialization is complete - nop if no agents.
|
|
JvmtiExport::post_vm_initialized();
|
|
|
|
if (TRACE_START() != JNI_OK) {
|
|
vm_exit_during_initialization("Failed to start tracing backend.");
|
|
}
|
|
|
|
if (CleanChunkPoolAsync) {
|
|
Chunk::start_chunk_pool_cleaner_task();
|
|
}
|
|
|
|
// initialize compiler(s)
|
|
#if defined(COMPILER1) || defined(COMPILER2) || defined(SHARK)
|
|
CompileBroker::compilation_init();
|
|
#endif
|
|
|
|
if (EnableInvokeDynamic) {
|
|
// Pre-initialize some JSR292 core classes to avoid deadlock during class loading.
|
|
// It is done after compilers are initialized, because otherwise compilations of
|
|
// signature polymorphic MH intrinsics can be missed
|
|
// (see SystemDictionary::find_method_handle_intrinsic).
|
|
initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK_0);
|
|
initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK_0);
|
|
}
|
|
|
|
#if INCLUDE_MANAGEMENT
|
|
Management::initialize(THREAD);
|
|
#endif // INCLUDE_MANAGEMENT
|
|
|
|
if (HAS_PENDING_EXCEPTION) {
|
|
// management agent fails to start possibly due to
|
|
// configuration problem and is responsible for printing
|
|
// stack trace if appropriate. Simply exit VM.
|
|
vm_exit(1);
|
|
}
|
|
|
|
if (Arguments::has_profile()) FlatProfiler::engage(main_thread, true);
|
|
if (MemProfiling) MemProfiler::engage();
|
|
StatSampler::engage();
|
|
if (CheckJNICalls) JniPeriodicChecker::engage();
|
|
|
|
BiasedLocking::init();
|
|
|
|
if (JDK_Version::current().post_vm_init_hook_enabled()) {
|
|
call_postVMInitHook(THREAD);
|
|
// The Java side of PostVMInitHook.run must deal with all
|
|
// exceptions and provide means of diagnosis.
|
|
if (HAS_PENDING_EXCEPTION) {
|
|
CLEAR_PENDING_EXCEPTION;
|
|
}
|
|
}
|
|
|
|
{
|
|
MutexLockerEx ml(PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
|
|
// Make sure the watcher thread can be started by WatcherThread::start()
|
|
// or by dynamic enrollment.
|
|
WatcherThread::make_startable();
|
|
// Start up the WatcherThread if there are any periodic tasks
|
|
// NOTE: All PeriodicTasks should be registered by now. If they
|
|
// aren't, late joiners might appear to start slowly (we might
|
|
// take a while to process their first tick).
|
|
if (PeriodicTask::num_tasks() > 0) {
|
|
WatcherThread::start();
|
|
}
|
|
}
|
|
|
|
// Give os specific code one last chance to start
|
|
os::init_3();
|
|
|
|
create_vm_timer.end();
|
|
#ifdef ASSERT
|
|
_vm_complete = true;
|
|
#endif
|
|
return JNI_OK;
|
|
}
|
|
|
|
// type for the Agent_OnLoad and JVM_OnLoad entry points
|
|
extern "C" {
|
|
typedef jint (JNICALL *OnLoadEntry_t)(JavaVM *, char *, void *);
|
|
}
|
|
// Find a command line agent library and return its entry point for
|
|
// -agentlib: -agentpath: -Xrun
|
|
// num_symbol_entries must be passed-in since only the caller knows the number of symbols in the array.
|
|
static OnLoadEntry_t lookup_on_load(AgentLibrary* agent, const char *on_load_symbols[], size_t num_symbol_entries) {
|
|
OnLoadEntry_t on_load_entry = NULL;
|
|
void *library = NULL;
|
|
|
|
if (!agent->valid()) {
|
|
char buffer[JVM_MAXPATHLEN];
|
|
char ebuf[1024];
|
|
const char *name = agent->name();
|
|
const char *msg = "Could not find agent library ";
|
|
|
|
// First check to see if agent is statically linked into executable
|
|
if (os::find_builtin_agent(agent, on_load_symbols, num_symbol_entries)) {
|
|
library = agent->os_lib();
|
|
} else if (agent->is_absolute_path()) {
|
|
library = os::dll_load(name, ebuf, sizeof ebuf);
|
|
if (library == NULL) {
|
|
const char *sub_msg = " in absolute path, with error: ";
|
|
size_t len = strlen(msg) + strlen(name) + strlen(sub_msg) + strlen(ebuf) + 1;
|
|
char *buf = NEW_C_HEAP_ARRAY(char, len, mtThread);
|
|
jio_snprintf(buf, len, "%s%s%s%s", msg, name, sub_msg, ebuf);
|
|
// If we can't find the agent, exit.
|
|
vm_exit_during_initialization(buf, NULL);
|
|
FREE_C_HEAP_ARRAY(char, buf, mtThread);
|
|
}
|
|
} else {
|
|
// Try to load the agent from the standard dll directory
|
|
if (os::dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
|
|
name)) {
|
|
library = os::dll_load(buffer, ebuf, sizeof ebuf);
|
|
}
|
|
if (library == NULL) { // Try the local directory
|
|
char ns[1] = {0};
|
|
if (os::dll_build_name(buffer, sizeof(buffer), ns, name)) {
|
|
library = os::dll_load(buffer, ebuf, sizeof ebuf);
|
|
}
|
|
if (library == NULL) {
|
|
const char *sub_msg = " on the library path, with error: ";
|
|
size_t len = strlen(msg) + strlen(name) + strlen(sub_msg) + strlen(ebuf) + 1;
|
|
char *buf = NEW_C_HEAP_ARRAY(char, len, mtThread);
|
|
jio_snprintf(buf, len, "%s%s%s%s", msg, name, sub_msg, ebuf);
|
|
// If we can't find the agent, exit.
|
|
vm_exit_during_initialization(buf, NULL);
|
|
FREE_C_HEAP_ARRAY(char, buf, mtThread);
|
|
}
|
|
}
|
|
}
|
|
agent->set_os_lib(library);
|
|
agent->set_valid();
|
|
}
|
|
|
|
// Find the OnLoad function.
|
|
on_load_entry =
|
|
CAST_TO_FN_PTR(OnLoadEntry_t, os::find_agent_function(agent,
|
|
false,
|
|
on_load_symbols,
|
|
num_symbol_entries));
|
|
return on_load_entry;
|
|
}
|
|
|
|
// Find the JVM_OnLoad entry point
|
|
static OnLoadEntry_t lookup_jvm_on_load(AgentLibrary* agent) {
|
|
const char *on_load_symbols[] = JVM_ONLOAD_SYMBOLS;
|
|
return lookup_on_load(agent, on_load_symbols, sizeof(on_load_symbols) / sizeof(char*));
|
|
}
|
|
|
|
// Find the Agent_OnLoad entry point
|
|
static OnLoadEntry_t lookup_agent_on_load(AgentLibrary* agent) {
|
|
const char *on_load_symbols[] = AGENT_ONLOAD_SYMBOLS;
|
|
return lookup_on_load(agent, on_load_symbols, sizeof(on_load_symbols) / sizeof(char*));
|
|
}
|
|
|
|
// For backwards compatibility with -Xrun
|
|
// Convert libraries with no JVM_OnLoad, but which have Agent_OnLoad to be
|
|
// treated like -agentpath:
|
|
// Must be called before agent libraries are created
|
|
void Threads::convert_vm_init_libraries_to_agents() {
|
|
AgentLibrary* agent;
|
|
AgentLibrary* next;
|
|
|
|
for (agent = Arguments::libraries(); agent != NULL; agent = next) {
|
|
next = agent->next(); // cache the next agent now as this agent may get moved off this list
|
|
OnLoadEntry_t on_load_entry = lookup_jvm_on_load(agent);
|
|
|
|
// If there is an JVM_OnLoad function it will get called later,
|
|
// otherwise see if there is an Agent_OnLoad
|
|
if (on_load_entry == NULL) {
|
|
on_load_entry = lookup_agent_on_load(agent);
|
|
if (on_load_entry != NULL) {
|
|
// switch it to the agent list -- so that Agent_OnLoad will be called,
|
|
// JVM_OnLoad won't be attempted and Agent_OnUnload will
|
|
Arguments::convert_library_to_agent(agent);
|
|
} else {
|
|
vm_exit_during_initialization("Could not find JVM_OnLoad or Agent_OnLoad function in the library", agent->name());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Create agents for -agentlib: -agentpath: and converted -Xrun
|
|
// Invokes Agent_OnLoad
|
|
// Called very early -- before JavaThreads exist
|
|
void Threads::create_vm_init_agents() {
|
|
extern struct JavaVM_ main_vm;
|
|
AgentLibrary* agent;
|
|
|
|
JvmtiExport::enter_onload_phase();
|
|
|
|
for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
|
|
OnLoadEntry_t on_load_entry = lookup_agent_on_load(agent);
|
|
|
|
if (on_load_entry != NULL) {
|
|
// Invoke the Agent_OnLoad function
|
|
jint err = (*on_load_entry)(&main_vm, agent->options(), NULL);
|
|
if (err != JNI_OK) {
|
|
vm_exit_during_initialization("agent library failed to init", agent->name());
|
|
}
|
|
} else {
|
|
vm_exit_during_initialization("Could not find Agent_OnLoad function in the agent library", agent->name());
|
|
}
|
|
}
|
|
JvmtiExport::enter_primordial_phase();
|
|
}
|
|
|
|
extern "C" {
|
|
typedef void (JNICALL *Agent_OnUnload_t)(JavaVM *);
|
|
}
|
|
|
|
void Threads::shutdown_vm_agents() {
|
|
// Send any Agent_OnUnload notifications
|
|
const char *on_unload_symbols[] = AGENT_ONUNLOAD_SYMBOLS;
|
|
size_t num_symbol_entries = ARRAY_SIZE(on_unload_symbols);
|
|
extern struct JavaVM_ main_vm;
|
|
for (AgentLibrary* agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
|
|
|
|
// Find the Agent_OnUnload function.
|
|
Agent_OnUnload_t unload_entry = CAST_TO_FN_PTR(Agent_OnUnload_t,
|
|
os::find_agent_function(agent,
|
|
false,
|
|
on_unload_symbols,
|
|
num_symbol_entries));
|
|
|
|
// Invoke the Agent_OnUnload function
|
|
if (unload_entry != NULL) {
|
|
JavaThread* thread = JavaThread::current();
|
|
ThreadToNativeFromVM ttn(thread);
|
|
HandleMark hm(thread);
|
|
(*unload_entry)(&main_vm);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Called for after the VM is initialized for -Xrun libraries which have not been converted to agent libraries
|
|
// Invokes JVM_OnLoad
|
|
void Threads::create_vm_init_libraries() {
|
|
extern struct JavaVM_ main_vm;
|
|
AgentLibrary* agent;
|
|
|
|
for (agent = Arguments::libraries(); agent != NULL; agent = agent->next()) {
|
|
OnLoadEntry_t on_load_entry = lookup_jvm_on_load(agent);
|
|
|
|
if (on_load_entry != NULL) {
|
|
// Invoke the JVM_OnLoad function
|
|
JavaThread* thread = JavaThread::current();
|
|
ThreadToNativeFromVM ttn(thread);
|
|
HandleMark hm(thread);
|
|
jint err = (*on_load_entry)(&main_vm, agent->options(), NULL);
|
|
if (err != JNI_OK) {
|
|
vm_exit_during_initialization("-Xrun library failed to init", agent->name());
|
|
}
|
|
} else {
|
|
vm_exit_during_initialization("Could not find JVM_OnLoad function in -Xrun library", agent->name());
|
|
}
|
|
}
|
|
}
|
|
|
|
// Last thread running calls java.lang.Shutdown.shutdown()
|
|
void JavaThread::invoke_shutdown_hooks() {
|
|
HandleMark hm(this);
|
|
|
|
// We could get here with a pending exception, if so clear it now.
|
|
if (this->has_pending_exception()) {
|
|
this->clear_pending_exception();
|
|
}
|
|
|
|
EXCEPTION_MARK;
|
|
Klass* k =
|
|
SystemDictionary::resolve_or_null(vmSymbols::java_lang_Shutdown(),
|
|
THREAD);
|
|
if (k != NULL) {
|
|
// SystemDictionary::resolve_or_null will return null if there was
|
|
// an exception. If we cannot load the Shutdown class, just don't
|
|
// call Shutdown.shutdown() at all. This will mean the shutdown hooks
|
|
// and finalizers (if runFinalizersOnExit is set) won't be run.
|
|
// Note that if a shutdown hook was registered or runFinalizersOnExit
|
|
// was called, the Shutdown class would have already been loaded
|
|
// (Runtime.addShutdownHook and runFinalizersOnExit will load it).
|
|
instanceKlassHandle shutdown_klass (THREAD, k);
|
|
JavaValue result(T_VOID);
|
|
JavaCalls::call_static(&result,
|
|
shutdown_klass,
|
|
vmSymbols::shutdown_method_name(),
|
|
vmSymbols::void_method_signature(),
|
|
THREAD);
|
|
}
|
|
CLEAR_PENDING_EXCEPTION;
|
|
}
|
|
|
|
// Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when
|
|
// the program falls off the end of main(). Another VM exit path is through
|
|
// vm_exit() when the program calls System.exit() to return a value or when
|
|
// there is a serious error in VM. The two shutdown paths are not exactly
|
|
// the same, but they share Shutdown.shutdown() at Java level and before_exit()
|
|
// and VM_Exit op at VM level.
|
|
//
|
|
// Shutdown sequence:
|
|
// + Shutdown native memory tracking if it is on
|
|
// + Wait until we are the last non-daemon thread to execute
|
|
// <-- every thing is still working at this moment -->
|
|
// + Call java.lang.Shutdown.shutdown(), which will invoke Java level
|
|
// shutdown hooks, run finalizers if finalization-on-exit
|
|
// + Call before_exit(), prepare for VM exit
|
|
// > run VM level shutdown hooks (they are registered through JVM_OnExit(),
|
|
// currently the only user of this mechanism is File.deleteOnExit())
|
|
// > stop flat profiler, StatSampler, watcher thread, CMS threads,
|
|
// post thread end and vm death events to JVMTI,
|
|
// stop signal thread
|
|
// + Call JavaThread::exit(), it will:
|
|
// > release JNI handle blocks, remove stack guard pages
|
|
// > remove this thread from Threads list
|
|
// <-- no more Java code from this thread after this point -->
|
|
// + Stop VM thread, it will bring the remaining VM to a safepoint and stop
|
|
// the compiler threads at safepoint
|
|
// <-- do not use anything that could get blocked by Safepoint -->
|
|
// + Disable tracing at JNI/JVM barriers
|
|
// + Set _vm_exited flag for threads that are still running native code
|
|
// + Delete this thread
|
|
// + Call exit_globals()
|
|
// > deletes tty
|
|
// > deletes PerfMemory resources
|
|
// + Return to caller
|
|
|
|
bool Threads::destroy_vm() {
|
|
JavaThread* thread = JavaThread::current();
|
|
|
|
#ifdef ASSERT
|
|
_vm_complete = false;
|
|
#endif
|
|
// Wait until we are the last non-daemon thread to execute
|
|
{ MutexLocker nu(Threads_lock);
|
|
while (Threads::number_of_non_daemon_threads() > 1 )
|
|
// This wait should make safepoint checks, wait without a timeout,
|
|
// and wait as a suspend-equivalent condition.
|
|
//
|
|
// Note: If the FlatProfiler is running and this thread is waiting
|
|
// for another non-daemon thread to finish, then the FlatProfiler
|
|
// is waiting for the external suspend request on this thread to
|
|
// complete. wait_for_ext_suspend_completion() will eventually
|
|
// timeout, but that takes time. Making this wait a suspend-
|
|
// equivalent condition solves that timeout problem.
|
|
//
|
|
Threads_lock->wait(!Mutex::_no_safepoint_check_flag, 0,
|
|
Mutex::_as_suspend_equivalent_flag);
|
|
}
|
|
|
|
// Hang forever on exit if we are reporting an error.
|
|
if (ShowMessageBoxOnError && is_error_reported()) {
|
|
os::infinite_sleep();
|
|
}
|
|
os::wait_for_keypress_at_exit();
|
|
|
|
if (JDK_Version::is_jdk12x_version()) {
|
|
// We are the last thread running, so check if finalizers should be run.
|
|
// For 1.3 or later this is done in thread->invoke_shutdown_hooks()
|
|
HandleMark rm(thread);
|
|
Universe::run_finalizers_on_exit();
|
|
} else {
|
|
// run Java level shutdown hooks
|
|
thread->invoke_shutdown_hooks();
|
|
}
|
|
|
|
before_exit(thread);
|
|
|
|
thread->exit(true);
|
|
|
|
// Stop VM thread.
|
|
{
|
|
// 4945125 The vm thread comes to a safepoint during exit.
|
|
// GC vm_operations can get caught at the safepoint, and the
|
|
// heap is unparseable if they are caught. Grab the Heap_lock
|
|
// to prevent this. The GC vm_operations will not be able to
|
|
// queue until after the vm thread is dead.
|
|
// After this point, we'll never emerge out of the safepoint before
|
|
// the VM exits, so concurrent GC threads do not need to be explicitly
|
|
// stopped; they remain inactive until the process exits.
|
|
// Note: some concurrent G1 threads may be running during a safepoint,
|
|
// but these will not be accessing the heap, just some G1-specific side
|
|
// data structures that are not accessed by any other threads but them
|
|
// after this point in a terminal safepoint.
|
|
|
|
MutexLocker ml(Heap_lock);
|
|
|
|
VMThread::wait_for_vm_thread_exit();
|
|
assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint");
|
|
VMThread::destroy();
|
|
}
|
|
|
|
// clean up ideal graph printers
|
|
#if defined(COMPILER2) && !defined(PRODUCT)
|
|
IdealGraphPrinter::clean_up();
|
|
#endif
|
|
|
|
// Now, all Java threads are gone except daemon threads. Daemon threads
|
|
// running Java code or in VM are stopped by the Safepoint. However,
|
|
// daemon threads executing native code are still running. But they
|
|
// will be stopped at native=>Java/VM barriers. Note that we can't
|
|
// simply kill or suspend them, as it is inherently deadlock-prone.
|
|
|
|
#ifndef PRODUCT
|
|
// disable function tracing at JNI/JVM barriers
|
|
TraceJNICalls = false;
|
|
TraceJVMCalls = false;
|
|
TraceRuntimeCalls = false;
|
|
#endif
|
|
|
|
VM_Exit::set_vm_exited();
|
|
|
|
notify_vm_shutdown();
|
|
|
|
delete thread;
|
|
|
|
// exit_globals() will delete tty
|
|
exit_globals();
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
jboolean Threads::is_supported_jni_version_including_1_1(jint version) {
|
|
if (version == JNI_VERSION_1_1) return JNI_TRUE;
|
|
return is_supported_jni_version(version);
|
|
}
|
|
|
|
|
|
jboolean Threads::is_supported_jni_version(jint version) {
|
|
if (version == JNI_VERSION_1_2) return JNI_TRUE;
|
|
if (version == JNI_VERSION_1_4) return JNI_TRUE;
|
|
if (version == JNI_VERSION_1_6) return JNI_TRUE;
|
|
if (version == JNI_VERSION_1_8) return JNI_TRUE;
|
|
return JNI_FALSE;
|
|
}
|
|
|
|
|
|
void Threads::add(JavaThread* p, bool force_daemon) {
|
|
// The threads lock must be owned at this point
|
|
assert_locked_or_safepoint(Threads_lock);
|
|
|
|
// See the comment for this method in thread.hpp for its purpose and
|
|
// why it is called here.
|
|
p->initialize_queues();
|
|
p->set_next(_thread_list);
|
|
_thread_list = p;
|
|
_number_of_threads++;
|
|
oop threadObj = p->threadObj();
|
|
bool daemon = true;
|
|
// Bootstrapping problem: threadObj can be null for initial
|
|
// JavaThread (or for threads attached via JNI)
|
|
if ((!force_daemon) && (threadObj == NULL || !java_lang_Thread::is_daemon(threadObj))) {
|
|
_number_of_non_daemon_threads++;
|
|
daemon = false;
|
|
}
|
|
|
|
p->set_safepoint_visible(true);
|
|
|
|
ThreadService::add_thread(p, daemon);
|
|
|
|
// Possible GC point.
|
|
Events::log(p, "Thread added: " INTPTR_FORMAT, p);
|
|
}
|
|
|
|
void Threads::remove(JavaThread* p) {
|
|
// Extra scope needed for Thread_lock, so we can check
|
|
// that we do not remove thread without safepoint code notice
|
|
{ MutexLocker ml(Threads_lock);
|
|
|
|
assert(includes(p), "p must be present");
|
|
|
|
JavaThread* current = _thread_list;
|
|
JavaThread* prev = NULL;
|
|
|
|
while (current != p) {
|
|
prev = current;
|
|
current = current->next();
|
|
}
|
|
|
|
if (prev) {
|
|
prev->set_next(current->next());
|
|
} else {
|
|
_thread_list = p->next();
|
|
}
|
|
_number_of_threads--;
|
|
oop threadObj = p->threadObj();
|
|
bool daemon = true;
|
|
if (threadObj == NULL || !java_lang_Thread::is_daemon(threadObj)) {
|
|
_number_of_non_daemon_threads--;
|
|
daemon = false;
|
|
|
|
// Only one thread left, do a notify on the Threads_lock so a thread waiting
|
|
// on destroy_vm will wake up.
|
|
if (number_of_non_daemon_threads() == 1)
|
|
Threads_lock->notify_all();
|
|
}
|
|
ThreadService::remove_thread(p, daemon);
|
|
|
|
// Make sure that safepoint code disregard this thread. This is needed since
|
|
// the thread might mess around with locks after this point. This can cause it
|
|
// to do callbacks into the safepoint code. However, the safepoint code is not aware
|
|
// of this thread since it is removed from the queue.
|
|
p->set_terminated_value();
|
|
|
|
// Now, this thread is not visible to safepoint
|
|
p->set_safepoint_visible(false);
|
|
// once the thread becomes safepoint invisible, we can not use its per-thread
|
|
// recorder. And Threads::do_threads() no longer walks this thread, so we have
|
|
// to release its per-thread recorder here.
|
|
MemTracker::thread_exiting(p);
|
|
} // unlock Threads_lock
|
|
|
|
// Since Events::log uses a lock, we grab it outside the Threads_lock
|
|
Events::log(p, "Thread exited: " INTPTR_FORMAT, p);
|
|
}
|
|
|
|
// Threads_lock must be held when this is called (or must be called during a safepoint)
|
|
bool Threads::includes(JavaThread* p) {
|
|
assert(Threads_lock->is_locked(), "sanity check");
|
|
ALL_JAVA_THREADS(q) {
|
|
if (q == p ) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// Operations on the Threads list for GC. These are not explicitly locked,
|
|
// but the garbage collector must provide a safe context for them to run.
|
|
// In particular, these things should never be called when the Threads_lock
|
|
// is held by some other thread. (Note: the Safepoint abstraction also
|
|
// uses the Threads_lock to gurantee this property. It also makes sure that
|
|
// all threads gets blocked when exiting or starting).
|
|
|
|
void Threads::oops_do(OopClosure* f, CLDToOopClosure* cld_f, CodeBlobClosure* cf) {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->oops_do(f, cld_f, cf);
|
|
}
|
|
VMThread::vm_thread()->oops_do(f, cld_f, cf);
|
|
}
|
|
|
|
void Threads::possibly_parallel_oops_do(OopClosure* f, CLDToOopClosure* cld_f, CodeBlobClosure* cf) {
|
|
// Introduce a mechanism allowing parallel threads to claim threads as
|
|
// root groups. Overhead should be small enough to use all the time,
|
|
// even in sequential code.
|
|
SharedHeap* sh = SharedHeap::heap();
|
|
// Cannot yet substitute active_workers for n_par_threads
|
|
// because of G1CollectedHeap::verify() use of
|
|
// SharedHeap::process_strong_roots(). n_par_threads == 0 will
|
|
// turn off parallelism in process_strong_roots while active_workers
|
|
// is being used for parallelism elsewhere.
|
|
bool is_par = sh->n_par_threads() > 0;
|
|
assert(!is_par ||
|
|
(SharedHeap::heap()->n_par_threads() ==
|
|
SharedHeap::heap()->workers()->active_workers()), "Mismatch");
|
|
int cp = SharedHeap::heap()->strong_roots_parity();
|
|
ALL_JAVA_THREADS(p) {
|
|
if (p->claim_oops_do(is_par, cp)) {
|
|
p->oops_do(f, cld_f, cf);
|
|
}
|
|
}
|
|
VMThread* vmt = VMThread::vm_thread();
|
|
if (vmt->claim_oops_do(is_par, cp)) {
|
|
vmt->oops_do(f, cld_f, cf);
|
|
}
|
|
}
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
// Used by ParallelScavenge
|
|
void Threads::create_thread_roots_tasks(GCTaskQueue* q) {
|
|
ALL_JAVA_THREADS(p) {
|
|
q->enqueue(new ThreadRootsTask(p));
|
|
}
|
|
q->enqueue(new ThreadRootsTask(VMThread::vm_thread()));
|
|
}
|
|
|
|
// Used by Parallel Old
|
|
void Threads::create_thread_roots_marking_tasks(GCTaskQueue* q) {
|
|
ALL_JAVA_THREADS(p) {
|
|
q->enqueue(new ThreadRootsMarkingTask(p));
|
|
}
|
|
q->enqueue(new ThreadRootsMarkingTask(VMThread::vm_thread()));
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
void Threads::nmethods_do(CodeBlobClosure* cf) {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->nmethods_do(cf);
|
|
}
|
|
VMThread::vm_thread()->nmethods_do(cf);
|
|
}
|
|
|
|
void Threads::metadata_do(void f(Metadata*)) {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->metadata_do(f);
|
|
}
|
|
}
|
|
|
|
void Threads::gc_epilogue() {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->gc_epilogue();
|
|
}
|
|
}
|
|
|
|
void Threads::gc_prologue() {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->gc_prologue();
|
|
}
|
|
}
|
|
|
|
void Threads::deoptimized_wrt_marked_nmethods() {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->deoptimized_wrt_marked_nmethods();
|
|
}
|
|
}
|
|
|
|
|
|
// Get count Java threads that are waiting to enter the specified monitor.
|
|
GrowableArray<JavaThread*>* Threads::get_pending_threads(int count,
|
|
address monitor, bool doLock) {
|
|
assert(doLock || SafepointSynchronize::is_at_safepoint(),
|
|
"must grab Threads_lock or be at safepoint");
|
|
GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count);
|
|
|
|
int i = 0;
|
|
{
|
|
MutexLockerEx ml(doLock ? Threads_lock : NULL);
|
|
ALL_JAVA_THREADS(p) {
|
|
if (p->is_Compiler_thread()) continue;
|
|
|
|
address pending = (address)p->current_pending_monitor();
|
|
if (pending == monitor) { // found a match
|
|
if (i < count) result->append(p); // save the first count matches
|
|
i++;
|
|
}
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
|
|
JavaThread *Threads::owning_thread_from_monitor_owner(address owner, bool doLock) {
|
|
assert(doLock ||
|
|
Threads_lock->owned_by_self() ||
|
|
SafepointSynchronize::is_at_safepoint(),
|
|
"must grab Threads_lock or be at safepoint");
|
|
|
|
// NULL owner means not locked so we can skip the search
|
|
if (owner == NULL) return NULL;
|
|
|
|
{
|
|
MutexLockerEx ml(doLock ? Threads_lock : NULL);
|
|
ALL_JAVA_THREADS(p) {
|
|
// first, see if owner is the address of a Java thread
|
|
if (owner == (address)p) return p;
|
|
}
|
|
}
|
|
// Cannot assert on lack of success here since this function may be
|
|
// used by code that is trying to report useful problem information
|
|
// like deadlock detection.
|
|
if (UseHeavyMonitors) return NULL;
|
|
|
|
//
|
|
// If we didn't find a matching Java thread and we didn't force use of
|
|
// heavyweight monitors, then the owner is the stack address of the
|
|
// Lock Word in the owning Java thread's stack.
|
|
//
|
|
JavaThread* the_owner = NULL;
|
|
{
|
|
MutexLockerEx ml(doLock ? Threads_lock : NULL);
|
|
ALL_JAVA_THREADS(q) {
|
|
if (q->is_lock_owned(owner)) {
|
|
the_owner = q;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
// cannot assert on lack of success here; see above comment
|
|
return the_owner;
|
|
}
|
|
|
|
// Threads::print_on() is called at safepoint by VM_PrintThreads operation.
|
|
void Threads::print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks) {
|
|
char buf[32];
|
|
st->print_cr(os::local_time_string(buf, sizeof(buf)));
|
|
|
|
st->print_cr("Full thread dump %s (%s %s):",
|
|
Abstract_VM_Version::vm_name(),
|
|
Abstract_VM_Version::vm_release(),
|
|
Abstract_VM_Version::vm_info_string()
|
|
);
|
|
st->cr();
|
|
|
|
#if INCLUDE_ALL_GCS
|
|
// Dump concurrent locks
|
|
ConcurrentLocksDump concurrent_locks;
|
|
if (print_concurrent_locks) {
|
|
concurrent_locks.dump_at_safepoint();
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
|
|
ALL_JAVA_THREADS(p) {
|
|
ResourceMark rm;
|
|
p->print_on(st);
|
|
if (print_stacks) {
|
|
if (internal_format) {
|
|
p->trace_stack();
|
|
} else {
|
|
p->print_stack_on(st);
|
|
}
|
|
}
|
|
st->cr();
|
|
#if INCLUDE_ALL_GCS
|
|
if (print_concurrent_locks) {
|
|
concurrent_locks.print_locks_on(p, st);
|
|
}
|
|
#endif // INCLUDE_ALL_GCS
|
|
}
|
|
|
|
VMThread::vm_thread()->print_on(st);
|
|
st->cr();
|
|
Universe::heap()->print_gc_threads_on(st);
|
|
WatcherThread* wt = WatcherThread::watcher_thread();
|
|
if (wt != NULL) {
|
|
wt->print_on(st);
|
|
st->cr();
|
|
}
|
|
CompileBroker::print_compiler_threads_on(st);
|
|
st->flush();
|
|
}
|
|
|
|
// Threads::print_on_error() is called by fatal error handler. It's possible
|
|
// that VM is not at safepoint and/or current thread is inside signal handler.
|
|
// Don't print stack trace, as the stack may not be walkable. Don't allocate
|
|
// memory (even in resource area), it might deadlock the error handler.
|
|
void Threads::print_on_error(outputStream* st, Thread* current, char* buf, int buflen) {
|
|
bool found_current = false;
|
|
st->print_cr("Java Threads: ( => current thread )");
|
|
ALL_JAVA_THREADS(thread) {
|
|
bool is_current = (current == thread);
|
|
found_current = found_current || is_current;
|
|
|
|
st->print("%s", is_current ? "=>" : " ");
|
|
|
|
st->print(PTR_FORMAT, thread);
|
|
st->print(" ");
|
|
thread->print_on_error(st, buf, buflen);
|
|
st->cr();
|
|
}
|
|
st->cr();
|
|
|
|
st->print_cr("Other Threads:");
|
|
if (VMThread::vm_thread()) {
|
|
bool is_current = (current == VMThread::vm_thread());
|
|
found_current = found_current || is_current;
|
|
st->print("%s", current == VMThread::vm_thread() ? "=>" : " ");
|
|
|
|
st->print(PTR_FORMAT, VMThread::vm_thread());
|
|
st->print(" ");
|
|
VMThread::vm_thread()->print_on_error(st, buf, buflen);
|
|
st->cr();
|
|
}
|
|
WatcherThread* wt = WatcherThread::watcher_thread();
|
|
if (wt != NULL) {
|
|
bool is_current = (current == wt);
|
|
found_current = found_current || is_current;
|
|
st->print("%s", is_current ? "=>" : " ");
|
|
|
|
st->print(PTR_FORMAT, wt);
|
|
st->print(" ");
|
|
wt->print_on_error(st, buf, buflen);
|
|
st->cr();
|
|
}
|
|
if (!found_current) {
|
|
st->cr();
|
|
st->print("=>" PTR_FORMAT " (exited) ", current);
|
|
current->print_on_error(st, buf, buflen);
|
|
st->cr();
|
|
}
|
|
}
|
|
|
|
// Internal SpinLock and Mutex
|
|
// Based on ParkEvent
|
|
|
|
// Ad-hoc mutual exclusion primitives: SpinLock and Mux
|
|
//
|
|
// We employ SpinLocks _only for low-contention, fixed-length
|
|
// short-duration critical sections where we're concerned
|
|
// about native mutex_t or HotSpot Mutex:: latency.
|
|
// The mux construct provides a spin-then-block mutual exclusion
|
|
// mechanism.
|
|
//
|
|
// Testing has shown that contention on the ListLock guarding gFreeList
|
|
// is common. If we implement ListLock as a simple SpinLock it's common
|
|
// for the JVM to devolve to yielding with little progress. This is true
|
|
// despite the fact that the critical sections protected by ListLock are
|
|
// extremely short.
|
|
//
|
|
// TODO-FIXME: ListLock should be of type SpinLock.
|
|
// We should make this a 1st-class type, integrated into the lock
|
|
// hierarchy as leaf-locks. Critically, the SpinLock structure
|
|
// should have sufficient padding to avoid false-sharing and excessive
|
|
// cache-coherency traffic.
|
|
|
|
|
|
typedef volatile int SpinLockT ;
|
|
|
|
void Thread::SpinAcquire (volatile int * adr, const char * LockName) {
|
|
if (Atomic::cmpxchg (1, adr, 0) == 0) {
|
|
return ; // normal fast-path return
|
|
}
|
|
|
|
// Slow-path : We've encountered contention -- Spin/Yield/Block strategy.
|
|
TEVENT (SpinAcquire - ctx) ;
|
|
int ctr = 0 ;
|
|
int Yields = 0 ;
|
|
for (;;) {
|
|
while (*adr != 0) {
|
|
++ctr ;
|
|
if ((ctr & 0xFFF) == 0 || !os::is_MP()) {
|
|
if (Yields > 5) {
|
|
// Consider using a simple NakedSleep() instead.
|
|
// Then SpinAcquire could be called by non-JVM threads
|
|
Thread::current()->_ParkEvent->park(1) ;
|
|
} else {
|
|
os::NakedYield() ;
|
|
++Yields ;
|
|
}
|
|
} else {
|
|
SpinPause() ;
|
|
}
|
|
}
|
|
if (Atomic::cmpxchg (1, adr, 0) == 0) return ;
|
|
}
|
|
}
|
|
|
|
void Thread::SpinRelease (volatile int * adr) {
|
|
assert (*adr != 0, "invariant") ;
|
|
OrderAccess::fence() ; // guarantee at least release consistency.
|
|
// Roach-motel semantics.
|
|
// It's safe if subsequent LDs and STs float "up" into the critical section,
|
|
// but prior LDs and STs within the critical section can't be allowed
|
|
// to reorder or float past the ST that releases the lock.
|
|
*adr = 0 ;
|
|
}
|
|
|
|
// muxAcquire and muxRelease:
|
|
//
|
|
// * muxAcquire and muxRelease support a single-word lock-word construct.
|
|
// The LSB of the word is set IFF the lock is held.
|
|
// The remainder of the word points to the head of a singly-linked list
|
|
// of threads blocked on the lock.
|
|
//
|
|
// * The current implementation of muxAcquire-muxRelease uses its own
|
|
// dedicated Thread._MuxEvent instance. If we're interested in
|
|
// minimizing the peak number of extant ParkEvent instances then
|
|
// we could eliminate _MuxEvent and "borrow" _ParkEvent as long
|
|
// as certain invariants were satisfied. Specifically, care would need
|
|
// to be taken with regards to consuming unpark() "permits".
|
|
// A safe rule of thumb is that a thread would never call muxAcquire()
|
|
// if it's enqueued (cxq, EntryList, WaitList, etc) and will subsequently
|
|
// park(). Otherwise the _ParkEvent park() operation in muxAcquire() could
|
|
// consume an unpark() permit intended for monitorenter, for instance.
|
|
// One way around this would be to widen the restricted-range semaphore
|
|
// implemented in park(). Another alternative would be to provide
|
|
// multiple instances of the PlatformEvent() for each thread. One
|
|
// instance would be dedicated to muxAcquire-muxRelease, for instance.
|
|
//
|
|
// * Usage:
|
|
// -- Only as leaf locks
|
|
// -- for short-term locking only as muxAcquire does not perform
|
|
// thread state transitions.
|
|
//
|
|
// Alternatives:
|
|
// * We could implement muxAcquire and muxRelease with MCS or CLH locks
|
|
// but with parking or spin-then-park instead of pure spinning.
|
|
// * Use Taura-Oyama-Yonenzawa locks.
|
|
// * It's possible to construct a 1-0 lock if we encode the lockword as
|
|
// (List,LockByte). Acquire will CAS the full lockword while Release
|
|
// will STB 0 into the LockByte. The 1-0 scheme admits stranding, so
|
|
// acquiring threads use timers (ParkTimed) to detect and recover from
|
|
// the stranding window. Thread/Node structures must be aligned on 256-byte
|
|
// boundaries by using placement-new.
|
|
// * Augment MCS with advisory back-link fields maintained with CAS().
|
|
// Pictorially: LockWord -> T1 <-> T2 <-> T3 <-> ... <-> Tn <-> Owner.
|
|
// The validity of the backlinks must be ratified before we trust the value.
|
|
// If the backlinks are invalid the exiting thread must back-track through the
|
|
// the forward links, which are always trustworthy.
|
|
// * Add a successor indication. The LockWord is currently encoded as
|
|
// (List, LOCKBIT:1). We could also add a SUCCBIT or an explicit _succ variable
|
|
// to provide the usual futile-wakeup optimization.
|
|
// See RTStt for details.
|
|
// * Consider schedctl.sc_nopreempt to cover the critical section.
|
|
//
|
|
|
|
|
|
typedef volatile intptr_t MutexT ; // Mux Lock-word
|
|
enum MuxBits { LOCKBIT = 1 } ;
|
|
|
|
void Thread::muxAcquire (volatile intptr_t * Lock, const char * LockName) {
|
|
intptr_t w = Atomic::cmpxchg_ptr (LOCKBIT, Lock, 0) ;
|
|
if (w == 0) return ;
|
|
if ((w & LOCKBIT) == 0 && Atomic::cmpxchg_ptr (w|LOCKBIT, Lock, w) == w) {
|
|
return ;
|
|
}
|
|
|
|
TEVENT (muxAcquire - Contention) ;
|
|
ParkEvent * const Self = Thread::current()->_MuxEvent ;
|
|
assert ((intptr_t(Self) & LOCKBIT) == 0, "invariant") ;
|
|
for (;;) {
|
|
int its = (os::is_MP() ? 100 : 0) + 1 ;
|
|
|
|
// Optional spin phase: spin-then-park strategy
|
|
while (--its >= 0) {
|
|
w = *Lock ;
|
|
if ((w & LOCKBIT) == 0 && Atomic::cmpxchg_ptr (w|LOCKBIT, Lock, w) == w) {
|
|
return ;
|
|
}
|
|
}
|
|
|
|
Self->reset() ;
|
|
Self->OnList = intptr_t(Lock) ;
|
|
// The following fence() isn't _strictly necessary as the subsequent
|
|
// CAS() both serializes execution and ratifies the fetched *Lock value.
|
|
OrderAccess::fence();
|
|
for (;;) {
|
|
w = *Lock ;
|
|
if ((w & LOCKBIT) == 0) {
|
|
if (Atomic::cmpxchg_ptr (w|LOCKBIT, Lock, w) == w) {
|
|
Self->OnList = 0 ; // hygiene - allows stronger asserts
|
|
return ;
|
|
}
|
|
continue ; // Interference -- *Lock changed -- Just retry
|
|
}
|
|
assert (w & LOCKBIT, "invariant") ;
|
|
Self->ListNext = (ParkEvent *) (w & ~LOCKBIT );
|
|
if (Atomic::cmpxchg_ptr (intptr_t(Self)|LOCKBIT, Lock, w) == w) break ;
|
|
}
|
|
|
|
while (Self->OnList != 0) {
|
|
Self->park() ;
|
|
}
|
|
}
|
|
}
|
|
|
|
void Thread::muxAcquireW (volatile intptr_t * Lock, ParkEvent * ev) {
|
|
intptr_t w = Atomic::cmpxchg_ptr (LOCKBIT, Lock, 0) ;
|
|
if (w == 0) return ;
|
|
if ((w & LOCKBIT) == 0 && Atomic::cmpxchg_ptr (w|LOCKBIT, Lock, w) == w) {
|
|
return ;
|
|
}
|
|
|
|
TEVENT (muxAcquire - Contention) ;
|
|
ParkEvent * ReleaseAfter = NULL ;
|
|
if (ev == NULL) {
|
|
ev = ReleaseAfter = ParkEvent::Allocate (NULL) ;
|
|
}
|
|
assert ((intptr_t(ev) & LOCKBIT) == 0, "invariant") ;
|
|
for (;;) {
|
|
guarantee (ev->OnList == 0, "invariant") ;
|
|
int its = (os::is_MP() ? 100 : 0) + 1 ;
|
|
|
|
// Optional spin phase: spin-then-park strategy
|
|
while (--its >= 0) {
|
|
w = *Lock ;
|
|
if ((w & LOCKBIT) == 0 && Atomic::cmpxchg_ptr (w|LOCKBIT, Lock, w) == w) {
|
|
if (ReleaseAfter != NULL) {
|
|
ParkEvent::Release (ReleaseAfter) ;
|
|
}
|
|
return ;
|
|
}
|
|
}
|
|
|
|
ev->reset() ;
|
|
ev->OnList = intptr_t(Lock) ;
|
|
// The following fence() isn't _strictly necessary as the subsequent
|
|
// CAS() both serializes execution and ratifies the fetched *Lock value.
|
|
OrderAccess::fence();
|
|
for (;;) {
|
|
w = *Lock ;
|
|
if ((w & LOCKBIT) == 0) {
|
|
if (Atomic::cmpxchg_ptr (w|LOCKBIT, Lock, w) == w) {
|
|
ev->OnList = 0 ;
|
|
// We call ::Release while holding the outer lock, thus
|
|
// artificially lengthening the critical section.
|
|
// Consider deferring the ::Release() until the subsequent unlock(),
|
|
// after we've dropped the outer lock.
|
|
if (ReleaseAfter != NULL) {
|
|
ParkEvent::Release (ReleaseAfter) ;
|
|
}
|
|
return ;
|
|
}
|
|
continue ; // Interference -- *Lock changed -- Just retry
|
|
}
|
|
assert (w & LOCKBIT, "invariant") ;
|
|
ev->ListNext = (ParkEvent *) (w & ~LOCKBIT );
|
|
if (Atomic::cmpxchg_ptr (intptr_t(ev)|LOCKBIT, Lock, w) == w) break ;
|
|
}
|
|
|
|
while (ev->OnList != 0) {
|
|
ev->park() ;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Release() must extract a successor from the list and then wake that thread.
|
|
// It can "pop" the front of the list or use a detach-modify-reattach (DMR) scheme
|
|
// similar to that used by ParkEvent::Allocate() and ::Release(). DMR-based
|
|
// Release() would :
|
|
// (A) CAS() or swap() null to *Lock, releasing the lock and detaching the list.
|
|
// (B) Extract a successor from the private list "in-hand"
|
|
// (C) attempt to CAS() the residual back into *Lock over null.
|
|
// If there were any newly arrived threads and the CAS() would fail.
|
|
// In that case Release() would detach the RATs, re-merge the list in-hand
|
|
// with the RATs and repeat as needed. Alternately, Release() might
|
|
// detach and extract a successor, but then pass the residual list to the wakee.
|
|
// The wakee would be responsible for reattaching and remerging before it
|
|
// competed for the lock.
|
|
//
|
|
// Both "pop" and DMR are immune from ABA corruption -- there can be
|
|
// multiple concurrent pushers, but only one popper or detacher.
|
|
// This implementation pops from the head of the list. This is unfair,
|
|
// but tends to provide excellent throughput as hot threads remain hot.
|
|
// (We wake recently run threads first).
|
|
|
|
void Thread::muxRelease (volatile intptr_t * Lock) {
|
|
for (;;) {
|
|
const intptr_t w = Atomic::cmpxchg_ptr (0, Lock, LOCKBIT) ;
|
|
assert (w & LOCKBIT, "invariant") ;
|
|
if (w == LOCKBIT) return ;
|
|
ParkEvent * List = (ParkEvent *) (w & ~LOCKBIT) ;
|
|
assert (List != NULL, "invariant") ;
|
|
assert (List->OnList == intptr_t(Lock), "invariant") ;
|
|
ParkEvent * nxt = List->ListNext ;
|
|
|
|
// The following CAS() releases the lock and pops the head element.
|
|
if (Atomic::cmpxchg_ptr (intptr_t(nxt), Lock, w) != w) {
|
|
continue ;
|
|
}
|
|
List->OnList = 0 ;
|
|
OrderAccess::fence() ;
|
|
List->unpark () ;
|
|
return ;
|
|
}
|
|
}
|
|
|
|
|
|
void Threads::verify() {
|
|
ALL_JAVA_THREADS(p) {
|
|
p->verify();
|
|
}
|
|
VMThread* thread = VMThread::vm_thread();
|
|
if (thread != NULL) thread->verify();
|
|
}
|