jdk8-mips64-public/hotspot: src/share/vm/jfr/recorder/storage/jfrBuffer.hpp@d2c2cd90513e (annotated)

src/share/vm/jfr/recorder/storage/jfrBuffer.hpp@d2c2cd90513e (annotated)

src/share/vm/jfr/recorder/storage/jfrBuffer.hpp

Wed, 17 Jun 2020 11:43:05 +0300

author: apetushkov
date: Wed, 17 Jun 2020 11:43:05 +0300
changeset 9928: d2c2cd90513e
parent 9858: b985cbb00e68
permissions: -rw-r--r--

8220293: Deadlock in JFR string pool
Reviewed-by: rehn, egahlin

 /*
  * Copyright (c) 2012, 2018, 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.
  *
  */
 #ifndef SHARE_VM_JFR_RECORDER_STORAGE_JFRBUFFER_HPP
 #define SHARE_VM_JFR_RECORDER_STORAGE_JFRBUFFER_HPP
 #include "memory/allocation.hpp"
 //
 // Represents a piece of committed memory.
 //
 // u1* _pos <-- next store position
 // u1* _top <-- next unflushed position
 //
 // const void* _identity <-- acquired by
 //
 // Must be the owner before attempting stores.
 // Use acquire() and/or try_acquire() for exclusive access
 // to the (entire) buffer (cas identity).
 //
 // Stores to the buffer should uphold transactional semantics.
 // A new _pos must be updated only after all intended stores have completed.
 // The relation between _pos and _top must hold atomically,
 // e.g. the delta must always be fully parsable.
 // _top can move concurrently by other threads but is always <= _pos.
 //
 class JfrBuffer {
  private:
   JfrBuffer* _next;
   JfrBuffer* _prev;
   const void* volatile _identity;
   u1* _pos;
   mutable const u1* volatile _top;
   u2 _flags;
   u2 _header_size;
   u4 _size;
   const u1* stable_top() const;
  public:
   JfrBuffer();
   bool initialize(size_t header_size, size_t size, const void* id = NULL);
   void reinitialize();
   void concurrent_reinitialization();
   size_t discard();
   JfrBuffer* next() const {
     return _next;
   }
   JfrBuffer* prev() const {
     return _prev;
   }
   void set_next(JfrBuffer* next) {
     _next = next;
   }
   void set_prev(JfrBuffer* prev) {
     _prev = prev;
   }
   const u1* start() const {
     return ((const u1*)this) + _header_size;
   }
   u1* start() {
     return ((u1*)this) + _header_size;
   }
   const u1* end() const {
     return start() + size();
   }
   const u1* pos() const {
     return _pos;
   }
   u1* pos() {
     return _pos;
   }
   u1** pos_address() {
     return (u1**)&_pos;
   }
   void set_pos(u1* new_pos) {
     assert(new_pos <= end(), "invariant");
     _pos = new_pos;
   }
   void set_pos(size_t size) {
     assert(_pos + size <= end(), "invariant");
     _pos += size;
   }
   const u1* top() const;
   void set_top(const u1* new_top);
   const u1* concurrent_top() const;
   void set_concurrent_top(const u1* new_top);
   size_t header_size() const {
     return _header_size;
   }
   size_t size() const {
     return _size * BytesPerWord;
   }
   size_t total_size() const {
     return header_size() + size();
   }
   size_t free_size() const {
     return end() - pos();
   }
   size_t unflushed_size() const;
   bool empty() const {
     return pos() == start();
   }
   const void* identity() const {
     return _identity;
   }
   void clear_identity();
   void acquire(const void* id);
   bool try_acquire(const void* id);
   bool acquired_by(const void* id) const;
   bool acquired_by_self() const;
   void release();
   void move(JfrBuffer* const to, size_t size);
   void concurrent_move_and_reinitialize(JfrBuffer* const to, size_t size);
   bool transient() const;
   void set_transient();
   void clear_transient();
   bool lease() const;
   void set_lease();
   void clear_lease();
   bool retired() const;
   void set_retired();
   void clear_retired();
 };
 class JfrAgeNode : public JfrBuffer {
  private:
   JfrBuffer* _retired;
  public:
   JfrAgeNode() : _retired(NULL) {}
   void set_retired_buffer(JfrBuffer* retired) {
     _retired = retired;
   }
   JfrBuffer* retired_buffer() const {
     return _retired;
   }
 };
 #endif // SHARE_VM_JFR_RECORDER_STORAGE_JFRBUFFER_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/jfr/recorder/storage/jfrBuffer.hpp@d2c2cd90513e (annotated)

src/share/vm/jfr/recorder/storage/jfrBuffer.hpp