--- a/hotspot/src/share/vm/compiler/compileBroker.cpp Fri Oct 24 08:35:29 2014 +0200
+++ b/hotspot/src/share/vm/compiler/compileBroker.cpp Fri Oct 24 14:25:46 2014 +0200
@@ -156,8 +156,6 @@
CompileQueue* CompileBroker::_c2_compile_queue = NULL;
CompileQueue* CompileBroker::_c1_compile_queue = NULL;
-GrowableArray<CompilerThread*>* CompileBroker::_compiler_threads = NULL;
-
class CompilationLog : public StringEventLog {
public:
@@ -649,13 +647,10 @@
lock()->notify_all();
}
-// ------------------------------------------------------------------
-// CompileQueue::get
-//
-// Get the next CompileTask from a CompileQueue
+/**
+ * Get the next CompileTask from a CompileQueue
+ */
CompileTask* CompileQueue::get() {
- NMethodSweeper::possibly_sweep();
-
MutexLocker locker(lock());
// If _first is NULL we have no more compile jobs. There are two reasons for
// having no compile jobs: First, we compiled everything we wanted. Second,
@@ -668,35 +663,16 @@
return NULL;
}
- if (UseCodeCacheFlushing && !CompileBroker::should_compile_new_jobs()) {
- // Wait a certain amount of time to possibly do another sweep.
- // We must wait until stack scanning has happened so that we can
- // transition a method's state from 'not_entrant' to 'zombie'.
- long wait_time = NmethodSweepCheckInterval * 1000;
- if (FLAG_IS_DEFAULT(NmethodSweepCheckInterval)) {
- // Only one thread at a time can do sweeping. Scale the
- // wait time according to the number of compiler threads.
- // As a result, the next sweep is likely to happen every 100ms
- // with an arbitrary number of threads that do sweeping.
- wait_time = 100 * CICompilerCount;
- }
- bool timeout = lock()->wait(!Mutex::_no_safepoint_check_flag, wait_time);
- if (timeout) {
- MutexUnlocker ul(lock());
- NMethodSweeper::possibly_sweep();
- }
- } else {
- // If there are no compilation tasks and we can compile new jobs
- // (i.e., there is enough free space in the code cache) there is
- // no need to invoke the sweeper. As a result, the hotness of methods
- // remains unchanged. This behavior is desired, since we want to keep
- // the stable state, i.e., we do not want to evict methods from the
- // code cache if it is unnecessary.
- // We need a timed wait here, since compiler threads can exit if compilation
- // is disabled forever. We use 5 seconds wait time; the exiting of compiler threads
- // is not critical and we do not want idle compiler threads to wake up too often.
- lock()->wait(!Mutex::_no_safepoint_check_flag, 5*1000);
- }
+ // If there are no compilation tasks and we can compile new jobs
+ // (i.e., there is enough free space in the code cache) there is
+ // no need to invoke the sweeper. As a result, the hotness of methods
+ // remains unchanged. This behavior is desired, since we want to keep
+ // the stable state, i.e., we do not want to evict methods from the
+ // code cache if it is unnecessary.
+ // We need a timed wait here, since compiler threads can exit if compilation
+ // is disabled forever. We use 5 seconds wait time; the exiting of compiler threads
+ // is not critical and we do not want idle compiler threads to wake up too often.
+ lock()->wait(!Mutex::_no_safepoint_check_flag, 5*1000);
}
if (CompileBroker::is_compilation_disabled_forever()) {
@@ -886,8 +862,8 @@
_compilers[1] = new SharkCompiler();
#endif // SHARK
- // Start the CompilerThreads
- init_compiler_threads(c1_count, c2_count);
+ // Start the compiler thread(s) and the sweeper thread
+ init_compiler_sweeper_threads(c1_count, c2_count);
// totalTime performance counter is always created as it is required
// by the implementation of java.lang.management.CompilationMBean.
{
@@ -991,13 +967,10 @@
}
-CompilerThread* CompileBroker::make_compiler_thread(const char* name, CompileQueue* queue, CompilerCounters* counters,
- AbstractCompiler* comp, TRAPS) {
- CompilerThread* compiler_thread = NULL;
-
- Klass* k =
- SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(),
- true, CHECK_0);
+JavaThread* CompileBroker::make_thread(const char* name, CompileQueue* queue, CompilerCounters* counters,
+ AbstractCompiler* comp, bool compiler_thread, TRAPS) {
+ JavaThread* thread = NULL;
+ Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK_0);
instanceKlassHandle klass (THREAD, k);
instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_0);
Handle string = java_lang_String::create_from_str(name, CHECK_0);
@@ -1015,7 +988,11 @@
{
MutexLocker mu(Threads_lock, THREAD);
- compiler_thread = new CompilerThread(queue, counters);
+ if (compiler_thread) {
+ thread = new CompilerThread(queue, counters);
+ } else {
+ thread = new CodeCacheSweeperThread();
+ }
// At this point the new CompilerThread data-races with this startup
// thread (which I believe is the primoridal thread and NOT the VM
// thread). This means Java bytecodes being executed at startup can
@@ -1028,12 +1005,12 @@
// in that case. However, since this must work and we do not allow
// exceptions anyway, check and abort if this fails.
- if (compiler_thread == NULL || compiler_thread->osthread() == NULL){
+ if (thread == NULL || thread->osthread() == NULL) {
vm_exit_during_initialization("java.lang.OutOfMemoryError",
os::native_thread_creation_failed_msg());
}
- java_lang_Thread::set_thread(thread_oop(), compiler_thread);
+ java_lang_Thread::set_thread(thread_oop(), thread);
// Note that this only sets the JavaThread _priority field, which by
// definition is limited to Java priorities and not OS priorities.
@@ -1054,24 +1031,26 @@
native_prio = os::java_to_os_priority[NearMaxPriority];
}
}
- os::set_native_priority(compiler_thread, native_prio);
+ os::set_native_priority(thread, native_prio);
java_lang_Thread::set_daemon(thread_oop());
- compiler_thread->set_threadObj(thread_oop());
- compiler_thread->set_compiler(comp);
- Threads::add(compiler_thread);
- Thread::start(compiler_thread);
+ thread->set_threadObj(thread_oop());
+ if (compiler_thread) {
+ thread->as_CompilerThread()->set_compiler(comp);
+ }
+ Threads::add(thread);
+ Thread::start(thread);
}
// Let go of Threads_lock before yielding
os::naked_yield(); // make sure that the compiler thread is started early (especially helpful on SOLARIS)
- return compiler_thread;
+ return thread;
}
-void CompileBroker::init_compiler_threads(int c1_compiler_count, int c2_compiler_count) {
+void CompileBroker::init_compiler_sweeper_threads(int c1_compiler_count, int c2_compiler_count) {
EXCEPTION_MARK;
#if !defined(ZERO) && !defined(SHARK)
assert(c2_compiler_count > 0 || c1_compiler_count > 0, "No compilers?");
@@ -1088,17 +1067,14 @@
int compiler_count = c1_compiler_count + c2_compiler_count;
- _compiler_threads =
- new (ResourceObj::C_HEAP, mtCompiler) GrowableArray<CompilerThread*>(compiler_count, true);
-
char name_buffer[256];
+ const bool compiler_thread = true;
for (int i = 0; i < c2_compiler_count; i++) {
// Create a name for our thread.
sprintf(name_buffer, "C2 CompilerThread%d", i);
CompilerCounters* counters = new CompilerCounters("compilerThread", i, CHECK);
// Shark and C2
- CompilerThread* new_thread = make_compiler_thread(name_buffer, _c2_compile_queue, counters, _compilers[1], CHECK);
- _compiler_threads->append(new_thread);
+ make_thread(name_buffer, _c2_compile_queue, counters, _compilers[1], compiler_thread, CHECK);
}
for (int i = c2_compiler_count; i < compiler_count; i++) {
@@ -1106,13 +1082,17 @@
sprintf(name_buffer, "C1 CompilerThread%d", i);
CompilerCounters* counters = new CompilerCounters("compilerThread", i, CHECK);
// C1
- CompilerThread* new_thread = make_compiler_thread(name_buffer, _c1_compile_queue, counters, _compilers[0], CHECK);
- _compiler_threads->append(new_thread);
+ make_thread(name_buffer, _c1_compile_queue, counters, _compilers[0], compiler_thread, CHECK);
}
if (UsePerfData) {
PerfDataManager::create_constant(SUN_CI, "threads", PerfData::U_Bytes, compiler_count, CHECK);
}
+
+ if (MethodFlushing) {
+ // Initialize the sweeper thread
+ make_thread("Sweeper thread", NULL, NULL, NULL, false, CHECK);
+ }
}
@@ -1759,13 +1739,6 @@
// We need this HandleMark to avoid leaking VM handles.
HandleMark hm(thread);
- // Check if the CodeCache is full
- int code_blob_type = 0;
- if (CodeCache::is_full(&code_blob_type)) {
- // The CodeHeap for code_blob_type is really full
- handle_full_code_cache(code_blob_type);
- }
-
CompileTask* task = queue->get();
if (task == NULL) {
continue;
@@ -1773,8 +1746,9 @@
// Give compiler threads an extra quanta. They tend to be bursty and
// this helps the compiler to finish up the job.
- if( CompilerThreadHintNoPreempt )
+ if (CompilerThreadHintNoPreempt) {
os::hint_no_preempt();
+ }
// trace per thread time and compile statistics
CompilerCounters* counters = ((CompilerThread*)thread)->counters();
@@ -2074,8 +2048,10 @@
}
/**
- * The CodeCache is full. Print out warning and disable compilation
- * or try code cache cleaning so compilation can continue later.
+ * The CodeCache is full. Print warning and disable compilation.
+ * Schedule code cache cleaning so compilation can continue later.
+ * This function needs to be called only from CodeCache::allocate(),
+ * since we currently handle a full code cache uniformly.
*/
void CompileBroker::handle_full_code_cache(int code_blob_type) {
UseInterpreter = true;
@@ -2107,10 +2083,6 @@
if (CompileBroker::set_should_compile_new_jobs(CompileBroker::stop_compilation)) {
NMethodSweeper::log_sweep("disable_compiler");
}
- // Switch to 'vm_state'. This ensures that possibly_sweep() can be called
- // without having to consider the state in which the current thread is.
- ThreadInVMfromUnknown in_vm;
- NMethodSweeper::possibly_sweep();
} else {
disable_compilation_forever();
}