jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1MarkSweep.cpp@8a5ea0a9ccc4 (annotated)

src/share/vm/gc_implementation/g1/g1MarkSweep.cpp@8a5ea0a9ccc4 (annotated)

src/share/vm/gc_implementation/g1/g1MarkSweep.cpp

Sat, 06 Oct 2012 01:17:44 -0700

author: johnc
date: Sat, 06 Oct 2012 01:17:44 -0700
changeset 4173: 8a5ea0a9ccc4
parent 4098: 8966c2d65d96
child 4384: b735136e0d82
permissions: -rw-r--r--

7127708: G1: change task num types from int to uint in concurrent mark
Summary: Change the type of various task num fields, parameters etc to unsigned and rename them to be more consistent with the other collectors. Code changes were also reviewed by Vitaly Davidovich.
Reviewed-by: johnc
Contributed-by: Kaushik Srenevasan <kaushik@twitter.com>

 /*
  * Copyright (c) 2001, 2012, 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/javaClasses.hpp"
 #include "classfile/symbolTable.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "classfile/vmSymbols.hpp"
 #include "code/codeCache.hpp"
 #include "code/icBuffer.hpp"
 #include "gc_implementation/g1/g1Log.hpp"
 #include "gc_implementation/g1/g1MarkSweep.hpp"
 #include "memory/gcLocker.hpp"
 #include "memory/genCollectedHeap.hpp"
 #include "memory/modRefBarrierSet.hpp"
 #include "memory/referencePolicy.hpp"
 #include "memory/space.hpp"
 #include "oops/instanceRefKlass.hpp"
 #include "oops/oop.inline.hpp"
 #include "prims/jvmtiExport.hpp"
 #include "runtime/aprofiler.hpp"
 #include "runtime/biasedLocking.hpp"
 #include "runtime/fprofiler.hpp"
 #include "runtime/synchronizer.hpp"
 #include "runtime/thread.hpp"
 #include "runtime/vmThread.hpp"
 #include "utilities/copy.hpp"
 #include "utilities/events.hpp"
 class HeapRegion;
 void G1MarkSweep::invoke_at_safepoint(ReferenceProcessor* rp,
                                       bool clear_all_softrefs) {
   assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
   SharedHeap* sh = SharedHeap::heap();
 #ifdef ASSERT
   if (sh->collector_policy()->should_clear_all_soft_refs()) {
     assert(clear_all_softrefs, "Policy should have been checked earler");
   }
 #endif
   // hook up weak ref data so it can be used during Mark-Sweep
   assert(GenMarkSweep::ref_processor() == NULL, "no stomping");
   assert(rp != NULL, "should be non-NULL");
   assert(rp == G1CollectedHeap::heap()->ref_processor_stw(), "Precondition");
   GenMarkSweep::_ref_processor = rp;
   rp->setup_policy(clear_all_softrefs);
   // When collecting the permanent generation Method*s may be moving,
   // so we either have to flush all bcp data or convert it into bci.
   CodeCache::gc_prologue();
   Threads::gc_prologue();
   bool marked_for_unloading = false;
   allocate_stacks();
   // We should save the marks of the currently locked biased monitors.
   // The marking doesn't preserve the marks of biased objects.
   BiasedLocking::preserve_marks();
   mark_sweep_phase1(marked_for_unloading, clear_all_softrefs);
   mark_sweep_phase2();
   // Don't add any more derived pointers during phase3
   COMPILER2_PRESENT(DerivedPointerTable::set_active(false));
   mark_sweep_phase3();
   mark_sweep_phase4();
   GenMarkSweep::restore_marks();
   BiasedLocking::restore_marks();
   GenMarkSweep::deallocate_stacks();
   // "free at last gc" is calculated from these.
   // CHF: cheating for now!!!
   //  Universe::set_heap_capacity_at_last_gc(Universe::heap()->capacity());
   //  Universe::set_heap_used_at_last_gc(Universe::heap()->used());
   Threads::gc_epilogue();
   CodeCache::gc_epilogue();
   JvmtiExport::gc_epilogue();
   // refs processing: clean slate
   GenMarkSweep::_ref_processor = NULL;
 }
 void G1MarkSweep::allocate_stacks() {
   GenMarkSweep::_preserved_count_max = 0;
   GenMarkSweep::_preserved_marks = NULL;
   GenMarkSweep::_preserved_count = 0;
 }
 void G1MarkSweep::mark_sweep_phase1(bool& marked_for_unloading,
                                     bool clear_all_softrefs) {
   // Recursively traverse all live objects and mark them
   TraceTime tm("phase 1", G1Log::fine() && Verbose, true, gclog_or_tty);
   GenMarkSweep::trace(" 1");
   SharedHeap* sh = SharedHeap::heap();
   // Need cleared claim bits for the strong roots processing
   ClassLoaderDataGraph::clear_claimed_marks();
   sh->process_strong_roots(true,  // activate StrongRootsScope
                            false, // not scavenging.
                            SharedHeap::SO_SystemClasses,
                            &GenMarkSweep::follow_root_closure,
                            &GenMarkSweep::follow_code_root_closure,
                            &GenMarkSweep::follow_klass_closure);
   // Process reference objects found during marking
   ReferenceProcessor* rp = GenMarkSweep::ref_processor();
   assert(rp == G1CollectedHeap::heap()->ref_processor_stw(), "Sanity");
   rp->setup_policy(clear_all_softrefs);
   rp->process_discovered_references(&GenMarkSweep::is_alive,
                                     &GenMarkSweep::keep_alive,
                                     &GenMarkSweep::follow_stack_closure,
                                     NULL);
   // Follow system dictionary roots and unload classes
   bool purged_class = SystemDictionary::do_unloading(&GenMarkSweep::is_alive);
   assert(GenMarkSweep::_marking_stack.is_empty(),
          "stack should be empty by now");
   // Follow code cache roots (has to be done after system dictionary,
   // assumes all live klasses are marked)
   CodeCache::do_unloading(&GenMarkSweep::is_alive, purged_class);
   GenMarkSweep::follow_stack();
   // Update subklass/sibling/implementor links of live klasses
   Klass::clean_weak_klass_links(&GenMarkSweep::is_alive);
   assert(GenMarkSweep::_marking_stack.is_empty(),
          "stack should be empty by now");
   // Visit interned string tables and delete unmarked oops
   StringTable::unlink(&GenMarkSweep::is_alive);
   // Clean up unreferenced symbols in symbol table.
   SymbolTable::unlink();
   assert(GenMarkSweep::_marking_stack.is_empty(),
          "stack should be empty by now");
   if (VerifyDuringGC) {
     HandleMark hm;  // handle scope
     COMPILER2_PRESENT(DerivedPointerTableDeactivate dpt_deact);
     gclog_or_tty->print(" VerifyDuringGC:(full)[Verifying ");
     Universe::heap()->prepare_for_verify();
     // Note: we can verify only the heap here. When an object is
     // marked, the previous value of the mark word (including
     // identity hash values, ages, etc) is preserved, and the mark
     // word is set to markOop::marked_value - effectively removing
     // any hash values from the mark word. These hash values are
     // used when verifying the dictionaries and so removing them
     // from the mark word can make verification of the dictionaries
     // fail. At the end of the GC, the orginal mark word values
     // (including hash values) are restored to the appropriate
     // objects.
     Universe::heap()->verify(/* silent      */ false,
                              /* option      */ VerifyOption_G1UseMarkWord);
     G1CollectedHeap* g1h = G1CollectedHeap::heap();
     gclog_or_tty->print_cr("]");
   }
 }
 class G1PrepareCompactClosure: public HeapRegionClosure {
   G1CollectedHeap* _g1h;
   ModRefBarrierSet* _mrbs;
   CompactPoint _cp;
   HumongousRegionSet _humongous_proxy_set;
   void free_humongous_region(HeapRegion* hr) {
     HeapWord* end = hr->end();
     size_t dummy_pre_used;
     FreeRegionList dummy_free_list("Dummy Free List for G1MarkSweep");
     assert(hr->startsHumongous(),
            "Only the start of a humongous region should be freed.");
     _g1h->free_humongous_region(hr, &dummy_pre_used, &dummy_free_list,
                                 &_humongous_proxy_set, false /* par */);
     hr->prepare_for_compaction(&_cp);
     // Also clear the part of the card table that will be unused after
     // compaction.
     _mrbs->clear(MemRegion(hr->compaction_top(), end));
     dummy_free_list.remove_all();
   }
 public:
   G1PrepareCompactClosure(CompactibleSpace* cs)
   : _g1h(G1CollectedHeap::heap()),
     _mrbs(G1CollectedHeap::heap()->mr_bs()),
     _cp(NULL, cs, cs->initialize_threshold()),
     _humongous_proxy_set("G1MarkSweep Humongous Proxy Set") { }
   void update_sets() {
     // We'll recalculate total used bytes and recreate the free list
     // at the end of the GC, so no point in updating those values here.
     _g1h->update_sets_after_freeing_regions(0, /* pre_used */
                                             NULL, /* free_list */
                                             NULL, /* old_proxy_set */
                                             &_humongous_proxy_set,
                                             false /* par */);
   }
   bool doHeapRegion(HeapRegion* hr) {
     if (hr->isHumongous()) {
       if (hr->startsHumongous()) {
         oop obj = oop(hr->bottom());
         if (obj->is_gc_marked()) {
           obj->forward_to(obj);
         } else  {
           free_humongous_region(hr);
         }
       } else {
         assert(hr->continuesHumongous(), "Invalid humongous.");
       }
     } else {
       hr->prepare_for_compaction(&_cp);
       // Also clear the part of the card table that will be unused after
       // compaction.
       _mrbs->clear(MemRegion(hr->compaction_top(), hr->end()));
     }
     return false;
   }
 };
 void G1MarkSweep::mark_sweep_phase2() {
   // Now all live objects are marked, compute the new object addresses.
   // It is not required that we traverse spaces in the same order in
   // phase2, phase3 and phase4, but the ValidateMarkSweep live oops
   // tracking expects us to do so. See comment under phase4.
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   TraceTime tm("phase 2", G1Log::fine() && Verbose, true, gclog_or_tty);
   GenMarkSweep::trace("2");
   // find the first region
   HeapRegion* r = g1h->region_at(0);
   CompactibleSpace* sp = r;
   if (r->isHumongous() && oop(r->bottom())->is_gc_marked()) {
     sp = r->next_compaction_space();
   }
   G1PrepareCompactClosure blk(sp);
   g1h->heap_region_iterate(&blk);
   blk.update_sets();
 }
 class G1AdjustPointersClosure: public HeapRegionClosure {
  public:
   bool doHeapRegion(HeapRegion* r) {
     if (r->isHumongous()) {
       if (r->startsHumongous()) {
         // We must adjust the pointers on the single H object.
         oop obj = oop(r->bottom());
         debug_only(GenMarkSweep::track_interior_pointers(obj));
         // point all the oops to the new location
         obj->adjust_pointers();
         debug_only(GenMarkSweep::check_interior_pointers());
       }
     } else {
       // This really ought to be "as_CompactibleSpace"...
       r->adjust_pointers();
     }
     return false;
   }
 };
 void G1MarkSweep::mark_sweep_phase3() {
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   // Adjust the pointers to reflect the new locations
   TraceTime tm("phase 3", G1Log::fine() && Verbose, true, gclog_or_tty);
   GenMarkSweep::trace("3");
   SharedHeap* sh = SharedHeap::heap();
   // Need cleared claim bits for the strong roots processing
   ClassLoaderDataGraph::clear_claimed_marks();
   sh->process_strong_roots(true,  // activate StrongRootsScope
                            false, // not scavenging.
                            SharedHeap::SO_AllClasses,
                            &GenMarkSweep::adjust_root_pointer_closure,
                            NULL,  // do not touch code cache here
                            &GenMarkSweep::adjust_klass_closure);
   assert(GenMarkSweep::ref_processor() == g1h->ref_processor_stw(), "Sanity");
   g1h->ref_processor_stw()->weak_oops_do(&GenMarkSweep::adjust_root_pointer_closure);
   // Now adjust pointers in remaining weak roots.  (All of which should
   // have been cleared if they pointed to non-surviving objects.)
   g1h->g1_process_weak_roots(&GenMarkSweep::adjust_root_pointer_closure,
                              &GenMarkSweep::adjust_pointer_closure);
   GenMarkSweep::adjust_marks();
   G1AdjustPointersClosure blk;
   g1h->heap_region_iterate(&blk);
 }
 class G1SpaceCompactClosure: public HeapRegionClosure {
 public:
   G1SpaceCompactClosure() {}
   bool doHeapRegion(HeapRegion* hr) {
     if (hr->isHumongous()) {
       if (hr->startsHumongous()) {
         oop obj = oop(hr->bottom());
         if (obj->is_gc_marked()) {
           obj->init_mark();
         } else {
           assert(hr->is_empty(), "Should have been cleared in phase 2.");
         }
         hr->reset_during_compaction();
       }
     } else {
       hr->compact();
     }
     return false;
   }
 };
 void G1MarkSweep::mark_sweep_phase4() {
   // All pointers are now adjusted, move objects accordingly
   // The ValidateMarkSweep live oops tracking expects us to traverse spaces
   // in the same order in phase2, phase3 and phase4. We don't quite do that
   // here (code and comment not fixed for perm removal), so we tell the validate code
   // to use a higher index (saved from phase2) when verifying perm_gen.
   G1CollectedHeap* g1h = G1CollectedHeap::heap();
   TraceTime tm("phase 4", G1Log::fine() && Verbose, true, gclog_or_tty);
   GenMarkSweep::trace("4");
   G1SpaceCompactClosure blk;
   g1h->heap_region_iterate(&blk);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1MarkSweep.cpp@8a5ea0a9ccc4 (annotated)

src/share/vm/gc_implementation/g1/g1MarkSweep.cpp