src/hotspot/share/gc/z/zStackWatermark.hpp

/*
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 * 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
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 *
 * 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.
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#ifndef SHARE_GC_Z_ZSTACKWATERMARK_HPP
#define SHARE_GC_Z_ZSTACKWATERMARK_HPP

#include "gc/shared/barrierSet.hpp"
#include "gc/shared/barrierSetNMethod.hpp"
#include "gc/shared/threadLocalAllocBuffer.hpp"
#include "gc/z/zBarrier.hpp"
#include "gc/z/zUncoloredRoot.hpp"
#include "memory/allocation.hpp"
#include "memory/iterator.hpp"
#include "oops/oopsHierarchy.hpp"
#include "runtime/stackWatermark.hpp"
#include "utilities/globalDefinitions.hpp"

class frame;
class JavaThread;

class ZOnStackCodeBlobClosure : public CodeBlobClosure {
private:
  BarrierSetNMethod* _bs_nm;

  virtual void do_code_blob(CodeBlob* cb);

public:
  ZOnStackCodeBlobClosure();
};

struct ZColorWatermark {
  uintptr_t _color;
  uintptr_t _watermark;

  bool covers(const ZColorWatermark& other) const;
};

class ZStackWatermark : public StackWatermark {
private:
  // Stores old watermarks, which describes the
  // colors of the non-processed part of the stack.
  const static int      _old_watermarks_max = 3;
  ZColorWatermark       _old_watermarks[_old_watermarks_max];
  int                   _old_watermarks_newest;

  ThreadLocalAllocStats _stats;

  uintptr_t prev_head_color() const;
  uintptr_t prev_frame_color(const frame& fr) const;
  void save_old_watermark();

  void process_head(void* context);

  virtual uint32_t epoch_id() const;
  virtual void start_processing_impl(void* context);
  virtual void process(const frame& fr, RegisterMap& register_map, void* context);

public:
  ZStackWatermark(JavaThread* jt);

  ThreadLocalAllocStats& stats();
};

#endif // SHARE_GC_Z_ZSTACKWATERMARK_HPP