jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1RootProcessor.cpp@38d6febe66af (annotated)

src/share/vm/gc_implementation/g1/g1RootProcessor.cpp@38d6febe66af (annotated)

src/share/vm/gc_implementation/g1/g1RootProcessor.cpp

Mon, 01 Dec 2014 15:24:56 +0100

author: mgerdin
date: Mon, 01 Dec 2014 15:24:56 +0100
changeset 7659: 38d6febe66af
child 7660: 3ca53859c3c7
permissions: -rw-r--r--

8075210: Refactor strong root processing in order to allow G1 to evolve separately from GenCollectedHeap
Summary: Create a G1RootProcessor and move SharedHeap root processing to GenCollectedHeap
Reviewed-by: brutisso, tschatzl, ehelin

 /*
  * 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");
   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 ((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(new SubTasksDone(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();
   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);
   // 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);
   // Now the CM ref_processor roots.
   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) {
     // 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.
     ClassLoaderDataGraph::roots_cld_do(NULL, scan_weak_clds);
   }
   // 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();
   G1GCPhaseTimes* phase_times = _g1h->g1_policy()->phase_times();
   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);
   process_vm_roots(oops, NULL);
   _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);
   process_vm_roots(oops, oops);
   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) {
   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.
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_ClassLoaderDataGraph_oops_do)) {
     ClassLoaderDataGraph::roots_cld_do(strong_clds, weak_clds);
   }
   Threads::possibly_parallel_oops_do(strong_roots, thread_stack_clds, strong_code);
 }
 void G1RootProcessor::process_vm_roots(OopClosure* strong_roots,
                                        OopClosure* weak_roots) {
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_Universe_oops_do)) {
     Universe::oops_do(strong_roots);
   }
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_JNIHandles_oops_do)) {
     JNIHandles::oops_do(strong_roots);
   }
   if (!_process_strong_tasks-> is_task_claimed(G1RP_PS_ObjectSynchronizer_oops_do)) {
     ObjectSynchronizer::oops_do(strong_roots);
   }
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_FlatProfiler_oops_do)) {
     FlatProfiler::oops_do(strong_roots);
   }
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_Management_oops_do)) {
     Management::oops_do(strong_roots);
   }
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_jvmti_oops_do)) {
     JvmtiExport::oops_do(strong_roots);
   }
   if (!_process_strong_tasks->is_task_claimed(G1RP_PS_SystemDictionary_oops_do)) {
     SystemDictionary::roots_oops_do(strong_roots, weak_roots);
   }
   // 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) {
   // 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);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1RootProcessor.cpp@38d6febe66af (annotated)

src/share/vm/gc_implementation/g1/g1RootProcessor.cpp