| /* |
| * Copyright (c) 2015, 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/symbolTable.hpp" |
| #include "classfile/systemDictionary.hpp" |
| #include "code/codeCache.hpp" |
| #include "gc_implementation/g1/bufferingOopClosure.hpp" |
| #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" |
| #include "gc_implementation/g1/g1CollectorPolicy.hpp" |
| #include "gc_implementation/g1/g1GCPhaseTimes.hpp" |
| #include "gc_implementation/g1/g1RemSet.inline.hpp" |
| #include "gc_implementation/g1/g1RootProcessor.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "runtime/fprofiler.hpp" |
| #include "runtime/mutex.hpp" |
| #include "services/management.hpp" |
| |
| class G1CodeBlobClosure : public CodeBlobClosure { |
| class HeapRegionGatheringOopClosure : public OopClosure { |
| G1CollectedHeap* _g1h; |
| OopClosure* _work; |
| nmethod* _nm; |
| |
| template <typename T> |
| void do_oop_work(T* p) { |
| _work->do_oop(p); |
| T oop_or_narrowoop = oopDesc::load_heap_oop(p); |
| if (!oopDesc::is_null(oop_or_narrowoop)) { |
| oop o = oopDesc::decode_heap_oop_not_null(oop_or_narrowoop); |
| HeapRegion* hr = _g1h->heap_region_containing_raw(o); |
| assert(!_g1h->obj_in_cs(o) || hr->rem_set()->strong_code_roots_list_contains(_nm), "if o still in CS then evacuation failed and nm must already be in the remset"); |
| hr->add_strong_code_root(_nm); |
| } |
| } |
| |
| public: |
| HeapRegionGatheringOopClosure(OopClosure* oc) : _g1h(G1CollectedHeap::heap()), _work(oc), _nm(NULL) {} |
| |
| void do_oop(oop* o) { |
| do_oop_work(o); |
| } |
| |
| void do_oop(narrowOop* o) { |
| do_oop_work(o); |
| } |
| |
| void set_nm(nmethod* nm) { |
| _nm = nm; |
| } |
| }; |
| |
| HeapRegionGatheringOopClosure _oc; |
| public: |
| G1CodeBlobClosure(OopClosure* oc) : _oc(oc) {} |
| |
| void do_code_blob(CodeBlob* cb) { |
| nmethod* nm = cb->as_nmethod_or_null(); |
| if (nm != NULL) { |
| if (!nm->test_set_oops_do_mark()) { |
| _oc.set_nm(nm); |
| nm->oops_do(&_oc); |
| nm->fix_oop_relocations(); |
| } |
| } |
| } |
| }; |
| |
| |
| void G1RootProcessor::worker_has_discovered_all_strong_classes() { |
| uint n_workers = _g1h->n_par_threads(); |
| assert(ClassUnloadingWithConcurrentMark, "Currently only needed when doing G1 Class Unloading"); |
| |
| if (n_workers > 0) { |
| uint new_value = (uint)Atomic::add(1, &_n_workers_discovered_strong_classes); |
| if (new_value == n_workers) { |
| // This thread is last. Notify the others. |
| MonitorLockerEx ml(&_lock, Mutex::_no_safepoint_check_flag); |
| _lock.notify_all(); |
| } |
| } |
| } |
| |
| void G1RootProcessor::wait_until_all_strong_classes_discovered() { |
| uint n_workers = _g1h->n_par_threads(); |
| assert(ClassUnloadingWithConcurrentMark, "Currently only needed when doing G1 Class Unloading"); |
| |
| if (n_workers > 0 && (uint)_n_workers_discovered_strong_classes != n_workers) { |
| MonitorLockerEx ml(&_lock, Mutex::_no_safepoint_check_flag); |
| while ((uint)_n_workers_discovered_strong_classes != n_workers) { |
| _lock.wait(Mutex::_no_safepoint_check_flag, 0, false); |
| } |
| } |
| } |
| |
| G1RootProcessor::G1RootProcessor(G1CollectedHeap* g1h) : |
| _g1h(g1h), |
| _process_strong_tasks(G1RP_PS_NumElements), |
| _srs(g1h), |
| _lock(Mutex::leaf, "G1 Root Scanning barrier lock", false), |
| _n_workers_discovered_strong_classes(0) {} |
| |
| void G1RootProcessor::evacuate_roots(OopClosure* scan_non_heap_roots, |
| OopClosure* scan_non_heap_weak_roots, |
| CLDClosure* scan_strong_clds, |
| CLDClosure* scan_weak_clds, |
| bool trace_metadata, |
| uint worker_i) { |
| // First scan the shared roots. |
| double ext_roots_start = os::elapsedTime(); |
| G1GCPhaseTimes* phase_times = _g1h->g1_policy()->phase_times(); |
| |
| BufferingOopClosure buf_scan_non_heap_roots(scan_non_heap_roots); |
| BufferingOopClosure buf_scan_non_heap_weak_roots(scan_non_heap_weak_roots); |
| |
| OopClosure* const weak_roots = &buf_scan_non_heap_weak_roots; |
| OopClosure* const strong_roots = &buf_scan_non_heap_roots; |
| |
| // CodeBlobClosures are not interoperable with BufferingOopClosures |
| G1CodeBlobClosure root_code_blobs(scan_non_heap_roots); |
| |
| process_java_roots(strong_roots, |
| trace_metadata ? scan_strong_clds : NULL, |
| scan_strong_clds, |
| trace_metadata ? NULL : scan_weak_clds, |
| &root_code_blobs, |
| phase_times, |
| worker_i); |
| |
| // This is the point where this worker thread will not find more strong CLDs/nmethods. |
| // Report this so G1 can synchronize the strong and weak CLDs/nmethods processing. |
| if (trace_metadata) { |
| worker_has_discovered_all_strong_classes(); |
| } |
| |
| process_vm_roots(strong_roots, weak_roots, phase_times, worker_i); |
| |
| { |
| // Now the CM ref_processor roots. |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::CMRefRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_refProcessor_oops_do)) { |
| // We need to treat the discovered reference lists of the |
| // concurrent mark ref processor as roots and keep entries |
| // (which are added by the marking threads) on them live |
| // until they can be processed at the end of marking. |
| _g1h->ref_processor_cm()->weak_oops_do(&buf_scan_non_heap_roots); |
| } |
| } |
| |
| if (trace_metadata) { |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::WaitForStrongCLD, worker_i); |
| // Barrier to make sure all workers passed |
| // the strong CLD and strong nmethods phases. |
| wait_until_all_strong_classes_discovered(); |
| } |
| |
| // Now take the complement of the strong CLDs. |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::WeakCLDRoots, worker_i); |
| ClassLoaderDataGraph::roots_cld_do(NULL, scan_weak_clds); |
| } else { |
| phase_times->record_time_secs(G1GCPhaseTimes::WaitForStrongCLD, worker_i, 0.0); |
| phase_times->record_time_secs(G1GCPhaseTimes::WeakCLDRoots, worker_i, 0.0); |
| } |
| |
| // Finish up any enqueued closure apps (attributed as object copy time). |
| buf_scan_non_heap_roots.done(); |
| buf_scan_non_heap_weak_roots.done(); |
| |
| double obj_copy_time_sec = buf_scan_non_heap_roots.closure_app_seconds() |
| + buf_scan_non_heap_weak_roots.closure_app_seconds(); |
| |
| phase_times->record_time_secs(G1GCPhaseTimes::ObjCopy, worker_i, obj_copy_time_sec); |
| |
| double ext_root_time_sec = os::elapsedTime() - ext_roots_start - obj_copy_time_sec; |
| |
| phase_times->record_time_secs(G1GCPhaseTimes::ExtRootScan, worker_i, ext_root_time_sec); |
| |
| // During conc marking we have to filter the per-thread SATB buffers |
| // to make sure we remove any oops into the CSet (which will show up |
| // as implicitly live). |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::SATBFiltering, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_filter_satb_buffers) && _g1h->mark_in_progress()) { |
| JavaThread::satb_mark_queue_set().filter_thread_buffers(); |
| } |
| } |
| |
| _process_strong_tasks.all_tasks_completed(); |
| } |
| |
| void G1RootProcessor::process_strong_roots(OopClosure* oops, |
| CLDClosure* clds, |
| CodeBlobClosure* blobs) { |
| |
| process_java_roots(oops, clds, clds, NULL, blobs, NULL, 0); |
| process_vm_roots(oops, NULL, NULL, 0); |
| |
| _process_strong_tasks.all_tasks_completed(); |
| } |
| |
| void G1RootProcessor::process_all_roots(OopClosure* oops, |
| CLDClosure* clds, |
| CodeBlobClosure* blobs) { |
| |
| process_java_roots(oops, NULL, clds, clds, NULL, NULL, 0); |
| process_vm_roots(oops, oops, NULL, 0); |
| |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_CodeCache_oops_do)) { |
| CodeCache::blobs_do(blobs); |
| } |
| |
| _process_strong_tasks.all_tasks_completed(); |
| } |
| |
| void G1RootProcessor::process_java_roots(OopClosure* strong_roots, |
| CLDClosure* thread_stack_clds, |
| CLDClosure* strong_clds, |
| CLDClosure* weak_clds, |
| CodeBlobClosure* strong_code, |
| G1GCPhaseTimes* phase_times, |
| uint worker_i) { |
| assert(thread_stack_clds == NULL || weak_clds == NULL, "There is overlap between those, only one may be set"); |
| // Iterating over the CLDG and the Threads are done early to allow us to |
| // first process the strong CLDs and nmethods and then, after a barrier, |
| // let the thread process the weak CLDs and nmethods. |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::CLDGRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_ClassLoaderDataGraph_oops_do)) { |
| ClassLoaderDataGraph::roots_cld_do(strong_clds, weak_clds); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::ThreadRoots, worker_i); |
| Threads::possibly_parallel_oops_do(strong_roots, thread_stack_clds, strong_code); |
| } |
| } |
| |
| void G1RootProcessor::process_vm_roots(OopClosure* strong_roots, |
| OopClosure* weak_roots, |
| G1GCPhaseTimes* phase_times, |
| uint worker_i) { |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::UniverseRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_Universe_oops_do)) { |
| Universe::oops_do(strong_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::JNIRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_JNIHandles_oops_do)) { |
| JNIHandles::oops_do(strong_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::ObjectSynchronizerRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_ObjectSynchronizer_oops_do)) { |
| ObjectSynchronizer::oops_do(strong_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::FlatProfilerRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_FlatProfiler_oops_do)) { |
| FlatProfiler::oops_do(strong_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::ManagementRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_Management_oops_do)) { |
| Management::oops_do(strong_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::JVMTIRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_jvmti_oops_do)) { |
| JvmtiExport::oops_do(strong_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::SystemDictionaryRoots, worker_i); |
| if (!_process_strong_tasks.is_task_claimed(G1RP_PS_SystemDictionary_oops_do)) { |
| SystemDictionary::roots_oops_do(strong_roots, weak_roots); |
| } |
| } |
| |
| { |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::StringTableRoots, worker_i); |
| // All threads execute the following. A specific chunk of buckets |
| // from the StringTable are the individual tasks. |
| if (weak_roots != NULL) { |
| StringTable::possibly_parallel_oops_do(weak_roots); |
| } |
| } |
| } |
| |
| void G1RootProcessor::scan_remembered_sets(G1ParPushHeapRSClosure* scan_rs, |
| OopClosure* scan_non_heap_weak_roots, |
| uint worker_i) { |
| G1GCPhaseTimes* phase_times = _g1h->g1_policy()->phase_times(); |
| G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::CodeCacheRoots, worker_i); |
| |
| // Now scan the complement of the collection set. |
| G1CodeBlobClosure scavenge_cs_nmethods(scan_non_heap_weak_roots); |
| |
| _g1h->g1_rem_set()->oops_into_collection_set_do(scan_rs, &scavenge_cs_nmethods, worker_i); |
| } |
| |
| void G1RootProcessor::set_num_workers(int active_workers) { |
| _process_strong_tasks.set_n_threads(active_workers); |
| } |
