src/hotspot/share/gc/g1/g1FullGCMarkTask.cpp
author sjohanss
Tue, 14 Nov 2017 11:33:23 +0100
changeset 47885 5caa1d5f74c1
child 50752 9d62da00bf15
permissions -rw-r--r--
8186571: Implementation: JEP 307: Parallel Full GC for G1 Summary: Improve G1 worst-case latencies by making the full GC parallel. Reviewed-by: tschatzl, sangheki, ehelin

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * 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.
 *
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#include "precompiled.hpp"
#include "gc/g1/g1CollectedHeap.hpp"
#include "gc/g1/g1FullCollector.hpp"
#include "gc/g1/g1FullGCMarker.hpp"
#include "gc/g1/g1FullGCMarkTask.hpp"
#include "gc/g1/g1FullGCOopClosures.inline.hpp"
#include "gc/g1/g1FullGCReferenceProcessorExecutor.hpp"
#include "gc/shared/gcTraceTime.inline.hpp"
#include "gc/shared/referenceProcessor.hpp"

G1FullGCMarkTask::G1FullGCMarkTask(G1FullCollector* collector) :
    G1FullGCTask("G1 Parallel Marking Task", collector),
    _root_processor(G1CollectedHeap::heap(), collector->workers()),
    _terminator(collector->workers(), collector->array_queue_set()) {
  // Need cleared claim bits for the roots processing
  ClassLoaderDataGraph::clear_claimed_marks();
}

void G1FullGCMarkTask::work(uint worker_id) {
  Ticks start = Ticks::now();
  ResourceMark rm;
  G1FullGCMarker* marker = collector()->marker(worker_id);
  MarkingCodeBlobClosure code_closure(marker->mark_closure(), !CodeBlobToOopClosure::FixRelocations);

  if (ClassUnloading) {
    _root_processor.process_strong_roots(
        marker->mark_closure(),
        marker->cld_closure(),
        &code_closure);
  } else {
    _root_processor.process_all_roots_no_string_table(
        marker->mark_closure(),
        marker->cld_closure(),
        &code_closure);
  }

  // Mark stack is populated, now process and drain it.
  marker->complete_marking(collector()->oop_queue_set(), collector()->array_queue_set(), &_terminator);

  // This is the point where the entire marking should have completed.
  assert(marker->oop_stack()->is_empty(), "Marking should have completed");
  assert(marker->objarray_stack()->is_empty(), "Array marking should have completed");
  log_task("Marking task", worker_id, start);
}