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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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13  * accompanied this code).
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24 
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "code/codeCache.hpp"
28 #include "gc_implementation/parallelScavenge/cardTableExtension.hpp"
29 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp"
30 #include "gc_implementation/parallelScavenge/psMarkSweep.hpp"
31 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
32 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
33 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
34 #include "gc_implementation/parallelScavenge/psTasks.hpp"
35 #include "memory/iterator.hpp"
36 #include "memory/universe.hpp"
37 #include "oops/oop.inline.hpp"
38 #include "oops/oop.psgc.inline.hpp"
39 #include "runtime/fprofiler.hpp"
40 #include "runtime/thread.hpp"
41 #include "runtime/vmThread.hpp"
42 #include "services/management.hpp"
43 #include "utilities/taskqueue.hpp"
44 
45 //
46 // ScavengeRootsTask
47 //
48 
do_it(GCTaskManager * manager,uint which)49 void ScavengeRootsTask::do_it(GCTaskManager* manager, uint which) {
50   assert(Universe::heap()->is_gc_active(), "called outside gc");
51 
52   PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
53   PSScavengeRootsClosure roots_closure(pm);
54   PSPromoteRootsClosure  roots_to_old_closure(pm);
55 
56   switch (_root_type) {
57     case universe:
58       Universe::oops_do(&roots_closure);
59       break;
60 
61     case jni_handles:
62       JNIHandles::oops_do(&roots_closure);
63       break;
64 
65     case threads:
66     {
67       ResourceMark rm;
68       CLDClosure* cld_closure = NULL; // Not needed. All CLDs are already visited.
69       Threads::oops_do(&roots_closure, cld_closure, NULL);
70     }
71     break;
72 
73     case object_synchronizer:
74       ObjectSynchronizer::oops_do(&roots_closure);
75       break;
76 
77     case flat_profiler:
78       FlatProfiler::oops_do(&roots_closure);
79       break;
80 
81     case system_dictionary:
82       SystemDictionary::oops_do(&roots_closure);
83       break;
84 
85     case class_loader_data:
86     {
87       PSScavengeKlassClosure klass_closure(pm);
88       ClassLoaderDataGraph::oops_do(&roots_closure, &klass_closure, false);
89     }
90     break;
91 
92     case management:
93       Management::oops_do(&roots_closure);
94       break;
95 
96     case jvmti:
97       JvmtiExport::oops_do(&roots_closure);
98       break;
99 
100 
101     case code_cache:
102       {
103         MarkingCodeBlobClosure each_scavengable_code_blob(&roots_to_old_closure, CodeBlobToOopClosure::FixRelocations);
104         CodeCache::scavenge_root_nmethods_do(&each_scavengable_code_blob);
105       }
106       break;
107 
108     default:
109       fatal("Unknown root type");
110   }
111 
112   // Do the real work
113   pm->drain_stacks(false);
114 }
115 
116 //
117 // ThreadRootsTask
118 //
119 
do_it(GCTaskManager * manager,uint which)120 void ThreadRootsTask::do_it(GCTaskManager* manager, uint which) {
121   assert(Universe::heap()->is_gc_active(), "called outside gc");
122 
123   PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
124   PSScavengeRootsClosure roots_closure(pm);
125   CLDClosure* roots_from_clds = NULL;  // Not needed. All CLDs are already visited.
126   MarkingCodeBlobClosure roots_in_blobs(&roots_closure, CodeBlobToOopClosure::FixRelocations);
127 
128   if (_java_thread != NULL)
129     _java_thread->oops_do(&roots_closure, roots_from_clds, &roots_in_blobs);
130 
131   if (_vm_thread != NULL)
132     _vm_thread->oops_do(&roots_closure, roots_from_clds, &roots_in_blobs);
133 
134   // Do the real work
135   pm->drain_stacks(false);
136 }
137 
138 //
139 // StealTask
140 //
141 
StealTask(ParallelTaskTerminator * t)142 StealTask::StealTask(ParallelTaskTerminator* t) :
143   _terminator(t) {}
144 
do_it(GCTaskManager * manager,uint which)145 void StealTask::do_it(GCTaskManager* manager, uint which) {
146   assert(Universe::heap()->is_gc_active(), "called outside gc");
147 
148   PSPromotionManager* pm =
149     PSPromotionManager::gc_thread_promotion_manager(which);
150   pm->drain_stacks(true);
151   guarantee(pm->stacks_empty(),
152             "stacks should be empty at this point");
153 
154   int random_seed = 17;
155   while(true) {
156     StarTask p;
157     if (PSPromotionManager::steal_depth(which, &random_seed, p)) {
158       TASKQUEUE_STATS_ONLY(pm->record_steal(p));
159       pm->process_popped_location_depth(p);
160       pm->drain_stacks_depth(true);
161     } else {
162       if (terminator()->offer_termination()) {
163         break;
164       }
165     }
166   }
167   guarantee(pm->stacks_empty(), "stacks should be empty at this point");
168 }
169 
170 //
171 // OldToYoungRootsTask
172 //
173 
do_it(GCTaskManager * manager,uint which)174 void OldToYoungRootsTask::do_it(GCTaskManager* manager, uint which) {
175   // There are not old-to-young pointers if the old gen is empty.
176   assert(!_gen->object_space()->is_empty(),
177     "Should not be called is there is no work");
178   assert(_gen != NULL, "Sanity");
179   assert(_gen->object_space()->contains(_gen_top) || _gen_top == _gen->object_space()->top(), "Sanity");
180   assert(_stripe_number < ParallelGCThreads, "Sanity");
181 
182   {
183     PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
184 
185     assert(Universe::heap()->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
186     CardTableExtension* card_table = (CardTableExtension *)Universe::heap()->barrier_set();
187     // FIX ME! Assert that card_table is the type we believe it to be.
188 
189     card_table->scavenge_contents_parallel(_gen->start_array(),
190                                            _gen->object_space(),
191                                            _gen_top,
192                                            pm,
193                                            _stripe_number,
194                                            _stripe_total);
195 
196     // Do the real work
197     pm->drain_stacks(false);
198   }
199 }
200