1 /*
   2  * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "code/codeCache.hpp"
  28 #include "gc_implementation/parallelScavenge/pcTasks.hpp"
  29 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
  30 #include "gc_interface/collectedHeap.hpp"
  31 #include "memory/universe.hpp"
  32 #include "oops/objArrayKlass.inline.hpp"
  33 #include "oops/oop.inline.hpp"
  34 #include "oops/oop.pcgc.inline.hpp"
  35 #include "prims/jvmtiExport.hpp"
  36 #include "runtime/fprofiler.hpp"
  37 #include "runtime/jniHandles.hpp"
  38 #include "runtime/thread.hpp"
  39 #include "runtime/vmThread.hpp"
  40 #include "services/management.hpp"
  41 
  42 //
  43 // ThreadRootsMarkingTask
  44 //
  45 
  46 void ThreadRootsMarkingTask::do_it(GCTaskManager* manager, uint which) {
  47   assert(Universe::heap()->is_gc_active(), "called outside gc");
  48 
  49   ResourceMark rm;
  50 
  51   NOT_PRODUCT(TraceTime tm("ThreadRootsMarkingTask",
  52     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
  53   ParCompactionManager* cm =
  54     ParCompactionManager::gc_thread_compaction_manager(which);
  55 
  56   PSParallelCompact::MarkAndPushClosure mark_and_push_closure(cm);
  57   CLDToOopClosure mark_and_push_from_clds(&mark_and_push_closure, true);
  58   CodeBlobToOopClosure mark_and_push_in_blobs(&mark_and_push_closure, /*do_marking=*/ true);
  59 
  60   if (_java_thread != NULL)
  61     _java_thread->oops_do(
  62         &mark_and_push_closure,
  63         &mark_and_push_from_clds,
  64         &mark_and_push_in_blobs);
  65 
  66   if (_vm_thread != NULL)
  67     _vm_thread->oops_do(
  68         &mark_and_push_closure,
  69         &mark_and_push_from_clds,
  70         &mark_and_push_in_blobs);
  71 
  72   // Do the real work
  73   cm->follow_marking_stacks();
  74 }
  75 
  76 
  77 void MarkFromRootsTask::do_it(GCTaskManager* manager, uint which) {
  78   assert(Universe::heap()->is_gc_active(), "called outside gc");
  79 
  80   NOT_PRODUCT(TraceTime tm("MarkFromRootsTask",
  81     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
  82   ParCompactionManager* cm =
  83     ParCompactionManager::gc_thread_compaction_manager(which);
  84   PSParallelCompact::MarkAndPushClosure mark_and_push_closure(cm);
  85   PSParallelCompact::FollowKlassClosure follow_klass_closure(&mark_and_push_closure);
  86 
  87   switch (_root_type) {
  88     case universe:
  89       Universe::oops_do(&mark_and_push_closure);
  90       break;
  91 
  92     case jni_handles:
  93       JNIHandles::oops_do(&mark_and_push_closure);
  94       break;
  95 
  96     case threads:
  97     {
  98       ResourceMark rm;
  99       CodeBlobToOopClosure each_active_code_blob(&mark_and_push_closure, /*do_marking=*/ true);
 100       CLDToOopClosure mark_and_push_from_cld(&mark_and_push_closure);
 101       Threads::oops_do(&mark_and_push_closure, &mark_and_push_from_cld, &each_active_code_blob);
 102     }
 103     break;
 104 
 105     case object_synchronizer:
 106       ObjectSynchronizer::oops_do(&mark_and_push_closure);
 107       break;
 108 
 109     case flat_profiler:
 110       FlatProfiler::oops_do(&mark_and_push_closure);
 111       break;
 112 
 113     case management:
 114       Management::oops_do(&mark_and_push_closure);
 115       break;
 116 
 117     case jvmti:
 118       JvmtiExport::oops_do(&mark_and_push_closure);
 119       break;
 120 
 121     case system_dictionary:
 122       SystemDictionary::always_strong_oops_do(&mark_and_push_closure);
 123       ClassLoaderDataGraph::always_strong_oops_do(&mark_and_push_closure, &follow_klass_closure, true);
 124       break;
 125 
 126     case code_cache:
 127       // Do not treat nmethods as strong roots for mark/sweep, since we can unload them.
 128       //CodeCache::scavenge_root_nmethods_do(CodeBlobToOopClosure(&mark_and_push_closure));
 129       break;
 130 
 131     default:
 132       fatal("Unknown root type");
 133   }
 134 
 135   // Do the real work
 136   cm->follow_marking_stacks();
 137 }
 138 
 139 
 140 //
 141 // RefProcTaskProxy
 142 //
 143 
 144 void RefProcTaskProxy::do_it(GCTaskManager* manager, uint which)
 145 {
 146   assert(Universe::heap()->is_gc_active(), "called outside gc");
 147 
 148   NOT_PRODUCT(TraceTime tm("RefProcTask",
 149     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
 150   ParCompactionManager* cm =
 151     ParCompactionManager::gc_thread_compaction_manager(which);
 152   PSParallelCompact::MarkAndPushClosure mark_and_push_closure(cm);
 153   PSParallelCompact::FollowStackClosure follow_stack_closure(cm);
 154   _rp_task.work(_work_id, *PSParallelCompact::is_alive_closure(),
 155                 mark_and_push_closure, follow_stack_closure);
 156 }
 157 
 158 //
 159 // RefProcTaskExecutor
 160 //
 161 
 162 void RefProcTaskExecutor::execute(ProcessTask& task)
 163 {
 164   ParallelScavengeHeap* heap = PSParallelCompact::gc_heap();
 165   uint parallel_gc_threads = heap->gc_task_manager()->workers();
 166   uint active_gc_threads = heap->gc_task_manager()->active_workers();
 167   RegionTaskQueueSet* qset = ParCompactionManager::region_array();
 168   ParallelTaskTerminator terminator(active_gc_threads, qset);
 169   GCTaskQueue* q = GCTaskQueue::create();
 170   for(uint i=0; i<parallel_gc_threads; i++) {
 171     q->enqueue(new RefProcTaskProxy(task, i));
 172   }
 173   if (task.marks_oops_alive()) {
 174     if (parallel_gc_threads>1) {
 175       for (uint j=0; j<active_gc_threads; j++) {
 176         q->enqueue(new StealMarkingTask(&terminator));
 177       }
 178     }
 179   }
 180   PSParallelCompact::gc_task_manager()->execute_and_wait(q);
 181 }
 182 
 183 void RefProcTaskExecutor::execute(EnqueueTask& task)
 184 {
 185   ParallelScavengeHeap* heap = PSParallelCompact::gc_heap();
 186   uint parallel_gc_threads = heap->gc_task_manager()->workers();
 187   GCTaskQueue* q = GCTaskQueue::create();
 188   for(uint i=0; i<parallel_gc_threads; i++) {
 189     q->enqueue(new RefEnqueueTaskProxy(task, i));
 190   }
 191   PSParallelCompact::gc_task_manager()->execute_and_wait(q);
 192 }
 193 
 194 //
 195 // StealMarkingTask
 196 //
 197 
 198 StealMarkingTask::StealMarkingTask(ParallelTaskTerminator* t) :
 199   _terminator(t) {}
 200 
 201 void StealMarkingTask::do_it(GCTaskManager* manager, uint which) {
 202   assert(Universe::heap()->is_gc_active(), "called outside gc");
 203 
 204   NOT_PRODUCT(TraceTime tm("StealMarkingTask",
 205     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
 206 
 207   ParCompactionManager* cm =
 208     ParCompactionManager::gc_thread_compaction_manager(which);
 209   PSParallelCompact::MarkAndPushClosure mark_and_push_closure(cm);
 210 
 211   oop obj = NULL;
 212   ObjArrayTask task;
 213   int random_seed = 17;
 214   do {
 215     while (ParCompactionManager::steal_objarray(which, &random_seed, task)) {
 216       ObjArrayKlass* k = (ObjArrayKlass*)task.obj()->klass();
 217       k->oop_follow_contents(cm, task.obj(), task.index());
 218       cm->follow_marking_stacks();
 219     }
 220     while (ParCompactionManager::steal(which, &random_seed, obj)) {
 221       obj->follow_contents(cm);
 222       cm->follow_marking_stacks();
 223     }
 224   } while (!terminator()->offer_termination());
 225 }
 226 
 227 //
 228 // StealRegionCompactionTask
 229 //
 230 
 231 StealRegionCompactionTask::StealRegionCompactionTask(ParallelTaskTerminator* t):
 232   _terminator(t) {}
 233 
 234 void StealRegionCompactionTask::do_it(GCTaskManager* manager, uint which) {
 235   assert(Universe::heap()->is_gc_active(), "called outside gc");
 236 
 237   NOT_PRODUCT(TraceTime tm("StealRegionCompactionTask",
 238     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
 239 
 240   ParCompactionManager* cm =
 241     ParCompactionManager::gc_thread_compaction_manager(which);
 242 
 243 
 244   // If not all threads are active, get a draining stack
 245   // from the list.  Else, just use this threads draining stack.
 246   uint which_stack_index;
 247   bool use_all_workers = manager->all_workers_active();
 248   if (use_all_workers) {
 249     which_stack_index = which;
 250     assert(manager->active_workers() == ParallelGCThreads,
 251            err_msg("all_workers_active has been incorrectly set: "
 252                    " active %d  ParallelGCThreads %d", manager->active_workers(),
 253                    ParallelGCThreads));
 254   } else {
 255     which_stack_index = ParCompactionManager::pop_recycled_stack_index();
 256   }
 257 
 258   cm->set_region_stack_index(which_stack_index);
 259   cm->set_region_stack(ParCompactionManager::region_list(which_stack_index));
 260   if (TraceDynamicGCThreads) {
 261     gclog_or_tty->print_cr("StealRegionCompactionTask::do_it "
 262                            "region_stack_index %d region_stack = 0x%x "
 263                            " empty (%d) use all workers %d",
 264     which_stack_index, ParCompactionManager::region_list(which_stack_index),
 265     cm->region_stack()->is_empty(),
 266     use_all_workers);
 267   }
 268 
 269   // Has to drain stacks first because there may be regions on
 270   // preloaded onto the stack and this thread may never have
 271   // done a draining task.  Are the draining tasks needed?
 272 
 273   cm->drain_region_stacks();
 274 
 275   size_t region_index = 0;
 276   int random_seed = 17;
 277 
 278   // If we're the termination task, try 10 rounds of stealing before
 279   // setting the termination flag
 280 
 281   while(true) {
 282     if (ParCompactionManager::steal(which, &random_seed, region_index)) {
 283       PSParallelCompact::fill_and_update_region(cm, region_index);
 284       cm->drain_region_stacks();
 285     } else {
 286       if (terminator()->offer_termination()) {
 287         break;
 288       }
 289       // Go around again.
 290     }
 291   }
 292   return;
 293 }
 294 
 295 UpdateDensePrefixTask::UpdateDensePrefixTask(
 296                                    PSParallelCompact::SpaceId space_id,
 297                                    size_t region_index_start,
 298                                    size_t region_index_end) :
 299   _space_id(space_id), _region_index_start(region_index_start),
 300   _region_index_end(region_index_end) {}
 301 
 302 void UpdateDensePrefixTask::do_it(GCTaskManager* manager, uint which) {
 303 
 304   NOT_PRODUCT(TraceTime tm("UpdateDensePrefixTask",
 305     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
 306 
 307   ParCompactionManager* cm =
 308     ParCompactionManager::gc_thread_compaction_manager(which);
 309 
 310   PSParallelCompact::update_and_deadwood_in_dense_prefix(cm,
 311                                                          _space_id,
 312                                                          _region_index_start,
 313                                                          _region_index_end);
 314 }
 315 
 316 void DrainStacksCompactionTask::do_it(GCTaskManager* manager, uint which) {
 317   assert(Universe::heap()->is_gc_active(), "called outside gc");
 318 
 319   NOT_PRODUCT(TraceTime tm("DrainStacksCompactionTask",
 320     PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
 321 
 322   ParCompactionManager* cm =
 323     ParCompactionManager::gc_thread_compaction_manager(which);
 324 
 325   uint which_stack_index;
 326   bool use_all_workers = manager->all_workers_active();
 327   if (use_all_workers) {
 328     which_stack_index = which;
 329     assert(manager->active_workers() == ParallelGCThreads,
 330            err_msg("all_workers_active has been incorrectly set: "
 331                    " active %d  ParallelGCThreads %d", manager->active_workers(),
 332                    ParallelGCThreads));
 333   } else {
 334     which_stack_index = stack_index();
 335   }
 336 
 337   cm->set_region_stack(ParCompactionManager::region_list(which_stack_index));
 338   if (TraceDynamicGCThreads) {
 339     gclog_or_tty->print_cr("DrainStacksCompactionTask::do_it which = %d "
 340                            "which_stack_index = %d/empty(%d) "
 341                            "use all workers %d",
 342                            which, which_stack_index,
 343                            cm->region_stack()->is_empty(),
 344                            use_all_workers);
 345   }
 346 
 347   cm->set_region_stack_index(which_stack_index);
 348 
 349   // Process any regions already in the compaction managers stacks.
 350   cm->drain_region_stacks();
 351 
 352   assert(cm->region_stack()->is_empty(), "Not empty");
 353 
 354   if (!use_all_workers) {
 355     // Always give up the region stack.
 356     assert(cm->region_stack() ==
 357            ParCompactionManager::region_list(cm->region_stack_index()),
 358            "region_stack and region_stack_index are inconsistent");
 359     ParCompactionManager::push_recycled_stack_index(cm->region_stack_index());
 360 
 361     if (TraceDynamicGCThreads) {
 362       void* old_region_stack = (void*) cm->region_stack();
 363       int old_region_stack_index = cm->region_stack_index();
 364       gclog_or_tty->print_cr("Pushing region stack 0x%x/%d",
 365         old_region_stack, old_region_stack_index);
 366     }
 367 
 368     cm->set_region_stack(NULL);
 369     cm->set_region_stack_index((uint)max_uintx);
 370   }
 371 }