1 /* 2 * Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_JFR_RECORDER_STORAGE_JFRVIRTUALMEMORY_HPP 26 #define SHARE_VM_JFR_RECORDER_STORAGE_JFRVIRTUALMEMORY_HPP 27 28 #include "jfr/utilities/jfrAllocation.hpp" 29 30 class JfrVirtualMemoryManager; 31 32 class JfrVirtualMemory : public JfrCHeapObj { 33 private: 34 JfrVirtualMemoryManager* _vmm; 35 const u1* _reserved_low; // lowest address of reservation 36 const u1* _reserved_high; // highest address of reservation 37 u1* _top; // current allocation address 38 const u1* _commit_point; // synch points for committing new memory 39 size_t _physical_commit_size_request_words; // aligned to os::vm_allocation_granularity() 40 size_t _aligned_datum_size_bytes; // datum alignment 41 42 bool commit_memory_block(); 43 void* commit(size_t block_size_request_words); 44 void* index_ptr(size_t index); // index to address map 45 46 public: 47 JfrVirtualMemory(); 48 ~JfrVirtualMemory(); 49 50 // initialization will do the reservation and return it 51 void* initialize(size_t reservation_size_request_bytes, size_t block_size_request_bytes, size_t datum_size_bytes = 1); 52 53 void* new_datum(); // datum oriented allocation 54 void* get(size_t index); // direct access retrieval 55 size_t aligned_datum_size_bytes() const; 56 57 bool is_full() const; // limit of reservation committed and in use 58 bool is_empty() const; 59 60 size_t count() const; // how many 61 size_t live_set() const; // how much resident memory (actually in use) 62 size_t reserved_size() const; // size of reservation 63 bool compact(size_t index); 64 }; 65 66 #endif // SHARE_VM_JFR_RECORDER_STORAGE_JFRVIRTUALMEMORY_HPP