1 /* 2 * Copyright (c) 2022, 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 #include "precompiled.hpp" 26 #include "memory/allocation.hpp" 27 #include "runtime/lockStack.hpp" 28 #include "runtime/safepoint.hpp" 29 #include "runtime/thread.hpp" 30 #include "utilities/copy.hpp" 31 #include "utilities/ostream.hpp" 32 33 LockStack::LockStack() : 34 _base(UseHeavyMonitors ? NULL : NEW_C_HEAP_ARRAY(oop, INITIAL_CAPACITY, mtSynchronizer)), 35 _limit(_base + INITIAL_CAPACITY), 36 _current(_base) { 37 } 38 39 LockStack::~LockStack() { 40 if (!UseHeavyMonitors) { 41 FREE_C_HEAP_ARRAY(oop, _base); 42 } 43 } 44 45 #ifndef PRODUCT 46 void LockStack::validate(const char* msg) const { 47 assert(!UseHeavyMonitors, "never use lock-stack when fast-locking is disabled"); 48 for (oop* loc1 = _base; loc1 < _current - 1; loc1++) { 49 for (oop* loc2 = loc1 + 1; loc2 < _current; loc2++) { 50 assert(*loc1 != *loc2, "entries must be unique: %s", msg); 51 } 52 } 53 } 54 #endif 55 56 void LockStack::grow(size_t min_capacity) { 57 // Grow stack. 58 assert(_limit > _base, "invariant"); 59 size_t capacity = _limit - _base; 60 size_t index = _current - _base; 61 size_t new_capacity = MAX2(min_capacity, capacity * 2); 62 oop* new_stack = NEW_C_HEAP_ARRAY(oop, new_capacity, mtSynchronizer); 63 for (size_t i = 0; i < index; i++) { 64 *(new_stack + i) = *(_base + i); 65 } 66 FREE_C_HEAP_ARRAY(oop, _base); 67 _base = new_stack; 68 _limit = _base + new_capacity; 69 _current = _base + index; 70 assert(_current < _limit, "must fit after growing"); 71 assert((_limit - _base) >= (ptrdiff_t) min_capacity, "must grow enough"); 72 } 73 74 void LockStack::grow() { 75 grow((_limit - _base) + 1); 76 } 77 78 void LockStack::grow(oop* required_limit) { 79 grow(required_limit - _base); 80 } 81 82 void LockStack::ensure_lock_stack_size(oop* _required_limit) { 83 JavaThread* jt = JavaThread::current(); 84 jt->lock_stack().grow(_required_limit); 85 }