8180932: Parallelize safepoint cleanup
Provide infrastructure to do safepoint cleanup tasks using parallel worker threads Reviewed-by: dholmes, rehn, dcubed, thartmann
This commit is contained in:
parent
d12604111c
commit
98bd53b5c2
@ -136,7 +136,7 @@ class nmethod : public CompiledMethod {
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// stack. An not_entrant method can be removed when there are no
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// more activations, i.e., when the _stack_traversal_mark is less than
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// current sweep traversal index.
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long _stack_traversal_mark;
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volatile jlong _stack_traversal_mark;
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// The _hotness_counter indicates the hotness of a method. The higher
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// the value the hotter the method. The hotness counter of a nmethod is
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@ -396,8 +396,8 @@ public:
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public:
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// Sweeper support
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long stack_traversal_mark() { return _stack_traversal_mark; }
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void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; }
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jlong stack_traversal_mark() { return OrderAccess::load_acquire(&_stack_traversal_mark); }
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void set_stack_traversal_mark(jlong l) { OrderAccess::release_store(&_stack_traversal_mark, l); }
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// implicit exceptions support
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address continuation_for_implicit_exception(address pc);
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@ -50,6 +50,7 @@ class MetaspaceSummary;
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class Thread;
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class ThreadClosure;
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class VirtualSpaceSummary;
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class WorkGang;
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class nmethod;
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class GCMessage : public FormatBuffer<1024> {
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@ -603,6 +604,16 @@ class CollectedHeap : public CHeapObj<mtInternal> {
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// unknown phase. The default implementation returns false.
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virtual bool request_concurrent_phase(const char* phase);
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// Provides a thread pool to SafepointSynchronize to use
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// for parallel safepoint cleanup.
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// GCs that use a GC worker thread pool may want to share
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// it for use during safepoint cleanup. This is only possible
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// if the GC can pause and resume concurrent work (e.g. G1
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// concurrent marking) for an intermittent non-GC safepoint.
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// If this method returns NULL, SafepointSynchronize will
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// perform cleanup tasks serially in the VMThread.
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virtual WorkGang* get_safepoint_workers() { return NULL; }
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// Non product verification and debugging.
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#ifndef PRODUCT
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// Support for PromotionFailureALot. Return true if it's time to cause a
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@ -33,6 +33,8 @@
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#include "code/scopeDesc.hpp"
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#include "gc/shared/collectedHeap.hpp"
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#include "gc/shared/gcLocker.inline.hpp"
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#include "gc/shared/strongRootsScope.hpp"
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#include "gc/shared/workgroup.hpp"
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#include "interpreter/interpreter.hpp"
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#include "logging/log.hpp"
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#include "logging/logStream.hpp"
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@ -543,64 +545,128 @@ static void event_safepoint_cleanup_task_commit(EventSafepointCleanupTask& event
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}
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}
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// Various cleaning tasks that should be done periodically at safepoints
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class ParallelSPCleanupThreadClosure : public ThreadClosure {
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private:
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CodeBlobClosure* _nmethod_cl;
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DeflateMonitorCounters* _counters;
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public:
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ParallelSPCleanupThreadClosure(DeflateMonitorCounters* counters) :
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_counters(counters),
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_nmethod_cl(NMethodSweeper::prepare_mark_active_nmethods()) {}
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void do_thread(Thread* thread) {
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ObjectSynchronizer::deflate_thread_local_monitors(thread, _counters);
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if (_nmethod_cl != NULL && thread->is_Java_thread() &&
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! thread->is_Code_cache_sweeper_thread()) {
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JavaThread* jt = (JavaThread*) thread;
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jt->nmethods_do(_nmethod_cl);
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}
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}
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};
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class ParallelSPCleanupTask : public AbstractGangTask {
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private:
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SubTasksDone _subtasks;
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ParallelSPCleanupThreadClosure _cleanup_threads_cl;
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uint _num_workers;
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DeflateMonitorCounters* _counters;
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public:
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ParallelSPCleanupTask(uint num_workers, DeflateMonitorCounters* counters) :
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AbstractGangTask("Parallel Safepoint Cleanup"),
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_cleanup_threads_cl(ParallelSPCleanupThreadClosure(counters)),
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_num_workers(num_workers),
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_subtasks(SubTasksDone(SafepointSynchronize::SAFEPOINT_CLEANUP_NUM_TASKS)),
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_counters(counters) {}
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void work(uint worker_id) {
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// All threads deflate monitors and mark nmethods (if necessary).
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Threads::parallel_java_threads_do(&_cleanup_threads_cl);
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if (!_subtasks.is_task_claimed(SafepointSynchronize::SAFEPOINT_CLEANUP_DEFLATE_MONITORS)) {
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const char* name = "deflating idle monitors";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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ObjectSynchronizer::deflate_idle_monitors(_counters);
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event_safepoint_cleanup_task_commit(event, name);
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}
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if (!_subtasks.is_task_claimed(SafepointSynchronize::SAFEPOINT_CLEANUP_UPDATE_INLINE_CACHES)) {
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const char* name = "updating inline caches";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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InlineCacheBuffer::update_inline_caches();
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event_safepoint_cleanup_task_commit(event, name);
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}
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if (!_subtasks.is_task_claimed(SafepointSynchronize::SAFEPOINT_CLEANUP_COMPILATION_POLICY)) {
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const char* name = "compilation policy safepoint handler";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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CompilationPolicy::policy()->do_safepoint_work();
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event_safepoint_cleanup_task_commit(event, name);
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}
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if (!_subtasks.is_task_claimed(SafepointSynchronize::SAFEPOINT_CLEANUP_SYMBOL_TABLE_REHASH)) {
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if (SymbolTable::needs_rehashing()) {
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const char* name = "rehashing symbol table";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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SymbolTable::rehash_table();
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event_safepoint_cleanup_task_commit(event, name);
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}
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}
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if (!_subtasks.is_task_claimed(SafepointSynchronize::SAFEPOINT_CLEANUP_STRING_TABLE_REHASH)) {
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if (StringTable::needs_rehashing()) {
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const char* name = "rehashing string table";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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StringTable::rehash_table();
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event_safepoint_cleanup_task_commit(event, name);
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}
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}
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if (!_subtasks.is_task_claimed(SafepointSynchronize::SAFEPOINT_CLEANUP_CLD_PURGE)) {
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// CMS delays purging the CLDG until the beginning of the next safepoint and to
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// make sure concurrent sweep is done
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const char* name = "purging class loader data graph";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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ClassLoaderDataGraph::purge_if_needed();
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event_safepoint_cleanup_task_commit(event, name);
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}
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_subtasks.all_tasks_completed(_num_workers);
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}
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};
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// Various cleaning tasks that should be done periodically at safepoints.
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void SafepointSynchronize::do_cleanup_tasks() {
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{
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const char* name = "deflating idle monitors";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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ObjectSynchronizer::deflate_idle_monitors();
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event_safepoint_cleanup_task_commit(event, name);
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TraceTime timer("safepoint cleanup tasks", TRACETIME_LOG(Info, safepoint, cleanup));
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// Prepare for monitor deflation.
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DeflateMonitorCounters deflate_counters;
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ObjectSynchronizer::prepare_deflate_idle_monitors(&deflate_counters);
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CollectedHeap* heap = Universe::heap();
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assert(heap != NULL, "heap not initialized yet?");
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WorkGang* cleanup_workers = heap->get_safepoint_workers();
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if (cleanup_workers != NULL) {
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// Parallel cleanup using GC provided thread pool.
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uint num_cleanup_workers = cleanup_workers->active_workers();
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ParallelSPCleanupTask cleanup(num_cleanup_workers, &deflate_counters);
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StrongRootsScope srs(num_cleanup_workers);
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cleanup_workers->run_task(&cleanup);
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} else {
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// Serial cleanup using VMThread.
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ParallelSPCleanupTask cleanup(1, &deflate_counters);
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StrongRootsScope srs(1);
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cleanup.work(0);
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}
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{
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const char* name = "updating inline caches";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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InlineCacheBuffer::update_inline_caches();
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event_safepoint_cleanup_task_commit(event, name);
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}
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{
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const char* name = "compilation policy safepoint handler";
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EventSafepointCleanupTask event;
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TraceTime timer("compilation policy safepoint handler", TRACETIME_LOG(Info, safepoint, cleanup));
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CompilationPolicy::policy()->do_safepoint_work();
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event_safepoint_cleanup_task_commit(event, name);
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}
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{
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const char* name = "mark nmethods";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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NMethodSweeper::mark_active_nmethods();
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event_safepoint_cleanup_task_commit(event, name);
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}
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if (SymbolTable::needs_rehashing()) {
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const char* name = "rehashing symbol table";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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SymbolTable::rehash_table();
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event_safepoint_cleanup_task_commit(event, name);
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}
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if (StringTable::needs_rehashing()) {
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const char* name = "rehashing string table";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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StringTable::rehash_table();
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event_safepoint_cleanup_task_commit(event, name);
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}
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{
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// CMS delays purging the CLDG until the beginning of the next safepoint and to
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// make sure concurrent sweep is done
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const char* name = "purging class loader data graph";
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EventSafepointCleanupTask event;
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TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
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ClassLoaderDataGraph::purge_if_needed();
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event_safepoint_cleanup_task_commit(event, name);
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}
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// Finish monitor deflation.
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ObjectSynchronizer::finish_deflate_idle_monitors(&deflate_counters);
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}
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@ -1,5 +1,5 @@
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/*
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* Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
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* Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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@ -75,6 +75,18 @@ class SafepointSynchronize : AllStatic {
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_blocking_timeout = 1
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};
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// The enums are listed in the order of the tasks when done serially.
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enum SafepointCleanupTasks {
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SAFEPOINT_CLEANUP_DEFLATE_MONITORS,
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SAFEPOINT_CLEANUP_UPDATE_INLINE_CACHES,
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SAFEPOINT_CLEANUP_COMPILATION_POLICY,
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SAFEPOINT_CLEANUP_SYMBOL_TABLE_REHASH,
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SAFEPOINT_CLEANUP_STRING_TABLE_REHASH,
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SAFEPOINT_CLEANUP_CLD_PURGE,
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// Leave this one last.
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SAFEPOINT_CLEANUP_NUM_TASKS
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};
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typedef struct {
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float _time_stamp; // record when the current safepoint occurs in seconds
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int _vmop_type; // type of VM operation triggers the safepoint
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@ -1,5 +1,5 @@
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/*
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* Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
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* Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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@ -53,7 +53,7 @@ class SweeperRecord {
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public:
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int traversal;
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int compile_id;
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long traversal_mark;
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jlong traversal_mark;
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int state;
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const char* kind;
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address vep;
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@ -62,7 +62,7 @@ class SweeperRecord {
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void print() {
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tty->print_cr("traversal = %d compile_id = %d %s uep = " PTR_FORMAT " vep = "
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PTR_FORMAT " state = %d traversal_mark %ld line = %d",
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PTR_FORMAT " state = %d traversal_mark "JLONG_FORMAT" line = %d",
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traversal,
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compile_id,
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kind == NULL ? "" : kind,
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@ -114,7 +114,7 @@ void NMethodSweeper::report_events() {
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void NMethodSweeper::record_sweep(CompiledMethod* nm, int line) {
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if (_records != NULL) {
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_records[_sweep_index].traversal = _traversals;
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_records[_sweep_index].traversal_mark = nm->is_nmethod() ? ((nmethod*)nm)->_stack_traversal_mark : 0;
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_records[_sweep_index].traversal_mark = nm->is_nmethod() ? ((nmethod*)nm)->stack_traversal_mark() : 0;
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_records[_sweep_index].compile_id = nm->compile_id();
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_records[_sweep_index].kind = nm->compile_kind();
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_records[_sweep_index].state = nm->get_state();
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@ -201,11 +201,18 @@ bool NMethodSweeper::wait_for_stack_scanning() {
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* safepoint.
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*/
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void NMethodSweeper::mark_active_nmethods() {
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CodeBlobClosure* cl = prepare_mark_active_nmethods();
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if (cl != NULL) {
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Threads::nmethods_do(cl);
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}
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}
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CodeBlobClosure* NMethodSweeper::prepare_mark_active_nmethods() {
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assert(SafepointSynchronize::is_at_safepoint(), "must be executed at a safepoint");
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// If we do not want to reclaim not-entrant or zombie methods there is no need
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// to scan stacks
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if (!MethodFlushing) {
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return;
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return NULL;
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}
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// Increase time so that we can estimate when to invoke the sweeper again.
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@ -233,14 +240,13 @@ void NMethodSweeper::mark_active_nmethods() {
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if (PrintMethodFlushing) {
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tty->print_cr("### Sweep: stack traversal %ld", _traversals);
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}
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Threads::nmethods_do(&mark_activation_closure);
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return &mark_activation_closure;
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} else {
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// Only set hotness counter
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Threads::nmethods_do(&set_hotness_closure);
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return &set_hotness_closure;
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}
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OrderAccess::storestore();
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}
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/**
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@ -1,5 +1,5 @@
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/*
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* Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
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* Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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@ -30,6 +30,8 @@ class WhiteBox;
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#include "code/codeCache.hpp"
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#include "utilities/ticks.hpp"
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class CodeBlobClosure;
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// An NmethodSweeper is an incremental cleaner for:
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// - cleanup inline caches
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// - reclamation of nmethods
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@ -114,6 +116,7 @@ class NMethodSweeper : public AllStatic {
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#endif
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static void mark_active_nmethods(); // Invoked at the end of each safepoint
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static CodeBlobClosure* prepare_mark_active_nmethods();
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static void sweeper_loop();
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static void notify(int code_blob_type); // Possibly start the sweeper thread.
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static void force_sweep();
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@ -1661,7 +1661,17 @@ bool ObjectSynchronizer::deflate_monitor(ObjectMonitor* mid, oop obj,
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// Walk a given monitor list, and deflate idle monitors
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// The given list could be a per-thread list or a global list
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// Caller acquires gListLock
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// Caller acquires gListLock.
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//
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// In the case of parallel processing of thread local monitor lists,
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// work is done by Threads::parallel_threads_do() which ensures that
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// each Java thread is processed by exactly one worker thread, and
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// thus avoid conflicts that would arise when worker threads would
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// process the same monitor lists concurrently.
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//
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// See also ParallelSPCleanupTask and
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// SafepointSynchronizer::do_cleanup_tasks() in safepoint.cpp and
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// Threads::parallel_java_threads_do() in thread.cpp.
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int ObjectSynchronizer::deflate_monitor_list(ObjectMonitor** listHeadp,
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ObjectMonitor** freeHeadp,
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ObjectMonitor** freeTailp) {
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@ -1692,11 +1702,14 @@ int ObjectSynchronizer::deflate_monitor_list(ObjectMonitor** listHeadp,
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return deflated_count;
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}
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void ObjectSynchronizer::deflate_idle_monitors() {
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void ObjectSynchronizer::prepare_deflate_idle_monitors(DeflateMonitorCounters* counters) {
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counters->nInuse = 0; // currently associated with objects
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counters->nInCirculation = 0; // extant
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counters->nScavenged = 0; // reclaimed
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}
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void ObjectSynchronizer::deflate_idle_monitors(DeflateMonitorCounters* counters) {
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assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
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int nInuse = 0; // currently associated with objects
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int nInCirculation = 0; // extant
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int nScavenged = 0; // reclaimed
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bool deflated = false;
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ObjectMonitor * freeHeadp = NULL; // Local SLL of scavenged monitors
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@ -1709,25 +1722,16 @@ void ObjectSynchronizer::deflate_idle_monitors() {
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Thread::muxAcquire(&gListLock, "scavenge - return");
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if (MonitorInUseLists) {
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int inUse = 0;
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for (JavaThread* cur = Threads::first(); cur != NULL; cur = cur->next()) {
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nInCirculation+= cur->omInUseCount;
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int deflated_count = deflate_monitor_list(cur->omInUseList_addr(), &freeHeadp, &freeTailp);
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cur->omInUseCount-= deflated_count;
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if (ObjectMonitor::Knob_VerifyInUse) {
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verifyInUse(cur);
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}
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nScavenged += deflated_count;
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nInuse += cur->omInUseCount;
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}
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// Note: the thread-local monitors lists get deflated in
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// a separate pass. See deflate_thread_local_monitors().
|
||||
|
||||
// For moribund threads, scan gOmInUseList
|
||||
if (gOmInUseList) {
|
||||
nInCirculation += gOmInUseCount;
|
||||
counters->nInCirculation += gOmInUseCount;
|
||||
int deflated_count = deflate_monitor_list((ObjectMonitor **)&gOmInUseList, &freeHeadp, &freeTailp);
|
||||
gOmInUseCount-= deflated_count;
|
||||
nScavenged += deflated_count;
|
||||
nInuse += gOmInUseCount;
|
||||
gOmInUseCount -= deflated_count;
|
||||
counters->nScavenged += deflated_count;
|
||||
counters->nInuse += gOmInUseCount;
|
||||
}
|
||||
|
||||
} else {
|
||||
@ -1736,7 +1740,7 @@ void ObjectSynchronizer::deflate_idle_monitors() {
|
||||
for (; block != NULL; block = (PaddedEnd<ObjectMonitor> *)next(block)) {
|
||||
// Iterate over all extant monitors - Scavenge all idle monitors.
|
||||
assert(block->object() == CHAINMARKER, "must be a block header");
|
||||
nInCirculation += _BLOCKSIZE;
|
||||
counters->nInCirculation += _BLOCKSIZE;
|
||||
for (int i = 1; i < _BLOCKSIZE; i++) {
|
||||
ObjectMonitor* mid = (ObjectMonitor*)&block[i];
|
||||
oop obj = (oop)mid->object();
|
||||
@ -1753,31 +1757,17 @@ void ObjectSynchronizer::deflate_idle_monitors() {
|
||||
|
||||
if (deflated) {
|
||||
mid->FreeNext = NULL;
|
||||
nScavenged++;
|
||||
counters->nScavenged++;
|
||||
} else {
|
||||
nInuse++;
|
||||
counters->nInuse++;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
gMonitorFreeCount += nScavenged;
|
||||
|
||||
// Consider: audit gFreeList to ensure that gMonitorFreeCount and list agree.
|
||||
|
||||
if (ObjectMonitor::Knob_Verbose) {
|
||||
tty->print_cr("INFO: Deflate: InCirc=%d InUse=%d Scavenged=%d "
|
||||
"ForceMonitorScavenge=%d : pop=%d free=%d",
|
||||
nInCirculation, nInuse, nScavenged, ForceMonitorScavenge,
|
||||
gMonitorPopulation, gMonitorFreeCount);
|
||||
tty->flush();
|
||||
}
|
||||
|
||||
ForceMonitorScavenge = 0; // Reset
|
||||
|
||||
// Move the scavenged monitors back to the global free list.
|
||||
if (freeHeadp != NULL) {
|
||||
guarantee(freeTailp != NULL && nScavenged > 0, "invariant");
|
||||
guarantee(freeTailp != NULL && counters->nScavenged > 0, "invariant");
|
||||
assert(freeTailp->FreeNext == NULL, "invariant");
|
||||
// constant-time list splice - prepend scavenged segment to gFreeList
|
||||
freeTailp->FreeNext = gFreeList;
|
||||
@ -1785,8 +1775,25 @@ void ObjectSynchronizer::deflate_idle_monitors() {
|
||||
}
|
||||
Thread::muxRelease(&gListLock);
|
||||
|
||||
OM_PERFDATA_OP(Deflations, inc(nScavenged));
|
||||
OM_PERFDATA_OP(MonExtant, set_value(nInCirculation));
|
||||
}
|
||||
|
||||
void ObjectSynchronizer::finish_deflate_idle_monitors(DeflateMonitorCounters* counters) {
|
||||
gMonitorFreeCount += counters->nScavenged;
|
||||
|
||||
// Consider: audit gFreeList to ensure that gMonitorFreeCount and list agree.
|
||||
|
||||
if (ObjectMonitor::Knob_Verbose) {
|
||||
tty->print_cr("INFO: Deflate: InCirc=%d InUse=%d Scavenged=%d "
|
||||
"ForceMonitorScavenge=%d : pop=%d free=%d",
|
||||
counters->nInCirculation, counters->nInuse, counters->nScavenged, ForceMonitorScavenge,
|
||||
gMonitorPopulation, gMonitorFreeCount);
|
||||
tty->flush();
|
||||
}
|
||||
|
||||
ForceMonitorScavenge = 0; // Reset
|
||||
|
||||
OM_PERFDATA_OP(Deflations, inc(counters->nScavenged));
|
||||
OM_PERFDATA_OP(MonExtant, set_value(counters->nInCirculation));
|
||||
|
||||
// TODO: Add objectMonitor leak detection.
|
||||
// Audit/inventory the objectMonitors -- make sure they're all accounted for.
|
||||
@ -1794,6 +1801,38 @@ void ObjectSynchronizer::deflate_idle_monitors() {
|
||||
GVars.stwCycle++;
|
||||
}
|
||||
|
||||
void ObjectSynchronizer::deflate_thread_local_monitors(Thread* thread, DeflateMonitorCounters* counters) {
|
||||
assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
|
||||
if (!MonitorInUseLists) return;
|
||||
|
||||
ObjectMonitor * freeHeadp = NULL; // Local SLL of scavenged monitors
|
||||
ObjectMonitor * freeTailp = NULL;
|
||||
|
||||
int deflated_count = deflate_monitor_list(thread->omInUseList_addr(), &freeHeadp, &freeTailp);
|
||||
|
||||
Thread::muxAcquire(&gListLock, "scavenge - return");
|
||||
|
||||
// Adjust counters
|
||||
counters->nInCirculation += thread->omInUseCount;
|
||||
thread->omInUseCount -= deflated_count;
|
||||
if (ObjectMonitor::Knob_VerifyInUse) {
|
||||
verifyInUse(thread);
|
||||
}
|
||||
counters->nScavenged += deflated_count;
|
||||
counters->nInuse += thread->omInUseCount;
|
||||
|
||||
// Move the scavenged monitors back to the global free list.
|
||||
if (freeHeadp != NULL) {
|
||||
guarantee(freeTailp != NULL && deflated_count > 0, "invariant");
|
||||
assert(freeTailp->FreeNext == NULL, "invariant");
|
||||
|
||||
// constant-time list splice - prepend scavenged segment to gFreeList
|
||||
freeTailp->FreeNext = gFreeList;
|
||||
gFreeList = freeHeadp;
|
||||
}
|
||||
Thread::muxRelease(&gListLock);
|
||||
}
|
||||
|
||||
// Monitor cleanup on JavaThread::exit
|
||||
|
||||
// Iterate through monitor cache and attempt to release thread's monitors
|
||||
|
@ -32,6 +32,12 @@
|
||||
|
||||
class ObjectMonitor;
|
||||
|
||||
struct DeflateMonitorCounters {
|
||||
int nInuse; // currently associated with objects
|
||||
int nInCirculation; // extant
|
||||
int nScavenged; // reclaimed
|
||||
};
|
||||
|
||||
class ObjectSynchronizer : AllStatic {
|
||||
friend class VMStructs;
|
||||
public:
|
||||
@ -127,7 +133,11 @@ class ObjectSynchronizer : AllStatic {
|
||||
// GC: we current use aggressive monitor deflation policy
|
||||
// Basically we deflate all monitors that are not busy.
|
||||
// An adaptive profile-based deflation policy could be used if needed
|
||||
static void deflate_idle_monitors();
|
||||
static void deflate_idle_monitors(DeflateMonitorCounters* counters);
|
||||
static void deflate_thread_local_monitors(Thread* thread, DeflateMonitorCounters* counters);
|
||||
static void prepare_deflate_idle_monitors(DeflateMonitorCounters* counters);
|
||||
static void finish_deflate_idle_monitors(DeflateMonitorCounters* counters);
|
||||
|
||||
// For a given monitor list: global or per-thread, deflate idle monitors
|
||||
static int deflate_monitor_list(ObjectMonitor** listheadp,
|
||||
ObjectMonitor** freeHeadp,
|
||||
|
@ -3385,6 +3385,15 @@ void Threads::threads_do(ThreadClosure* tc) {
|
||||
// If CompilerThreads ever become non-JavaThreads, add them here
|
||||
}
|
||||
|
||||
void Threads::parallel_java_threads_do(ThreadClosure* tc) {
|
||||
int cp = Threads::thread_claim_parity();
|
||||
ALL_JAVA_THREADS(p) {
|
||||
if (p->claim_oops_do(true, cp)) {
|
||||
tc->do_thread(p);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// The system initialization in the library has three phases.
|
||||
//
|
||||
// Phase 1: java.lang.System class initialization
|
||||
|
@ -2069,6 +2069,7 @@ class Threads: AllStatic {
|
||||
static bool includes(JavaThread* p);
|
||||
static JavaThread* first() { return _thread_list; }
|
||||
static void threads_do(ThreadClosure* tc);
|
||||
static void parallel_java_threads_do(ThreadClosure* tc);
|
||||
|
||||
// Initializes the vm and creates the vm thread
|
||||
static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
|
||||
|
@ -902,7 +902,7 @@ typedef RehashableHashtable<Symbol*, mtSymbol> RehashableSymbolHashtable;
|
||||
nonstatic_field(nmethod, _verified_entry_point, address) \
|
||||
nonstatic_field(nmethod, _osr_entry_point, address) \
|
||||
volatile_nonstatic_field(nmethod, _lock_count, jint) \
|
||||
nonstatic_field(nmethod, _stack_traversal_mark, long) \
|
||||
volatile_nonstatic_field(nmethod, _stack_traversal_mark, jlong) \
|
||||
nonstatic_field(nmethod, _compile_id, int) \
|
||||
nonstatic_field(nmethod, _comp_level, int) \
|
||||
\
|
||||
|
@ -38,10 +38,10 @@ public class SafepointCleanupTest {
|
||||
static void analyzeOutputOn(ProcessBuilder pb) throws Exception {
|
||||
OutputAnalyzer output = new OutputAnalyzer(pb.start());
|
||||
output.shouldContain("[safepoint,cleanup]");
|
||||
output.shouldContain("safepoint cleanup tasks");
|
||||
output.shouldContain("deflating idle monitors");
|
||||
output.shouldContain("updating inline caches");
|
||||
output.shouldContain("compilation policy safepoint handler");
|
||||
output.shouldContain("mark nmethods");
|
||||
output.shouldContain("purging class loader data graph");
|
||||
output.shouldHaveExitValue(0);
|
||||
}
|
||||
|
Loading…
x
Reference in New Issue
Block a user