1 /* 2 * Copyright (c) 1997, 2015, 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.inline.hpp" 27 #include "oops/constantPool.hpp" 28 #include "oops/oop.inline.hpp" 29 #include "runtime/atomic.inline.hpp" 30 #include "runtime/handles.inline.hpp" 31 #include "runtime/thread.inline.hpp" 32 33 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 34 35 #ifdef ASSERT 36 oop* HandleArea::allocate_handle(oop obj) { 37 assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark"); 38 assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark"); 39 if (ShenandoahVerifyReadsToFromSpace) { 40 obj = oopDesc::bs()->read_barrier(obj); 41 } 42 assert(obj->is_oop(), err_msg("not an oop: " INTPTR_FORMAT, (intptr_t*) obj)); 43 return real_allocate_handle(obj); 44 } 45 46 Handle::Handle(Thread* thread, oop obj) { 47 assert(thread == Thread::current(), "sanity check"); 48 if (obj == NULL) { 49 _handle = NULL; 50 } else { 51 _handle = thread->handle_area()->allocate_handle(obj); 52 } 53 } 54 55 #endif 56 57 static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) { 58 oop* bottom = (oop*) chunk->bottom(); 59 oop* top = (oop*) chunk_top; 60 uintx handles_visited = top - bottom; 61 assert(top >= bottom && top <= (oop*) chunk->top(), "just checking"); 62 // during GC phase 3, a handle may be a forward pointer that 63 // is not yet valid, so loosen the assertion 64 while (bottom < top) { 65 // This test can be moved up but for now check every oop. 66 67 assert((*bottom)->is_oop(), "handle should point to oop"); 68 69 f->do_oop(bottom++); 70 } 71 return handles_visited; 72 } 73 74 // Used for debugging handle allocation. 75 NOT_PRODUCT(jint _nof_handlemarks = 0;) 76 77 void HandleArea::oops_do(OopClosure* f) { 78 uintx handles_visited = 0; 79 // First handle the current chunk. It is filled to the high water mark. 80 handles_visited += chunk_oops_do(f, _chunk, _hwm); 81 // Then handle all previous chunks. They are completely filled. 82 Chunk* k = _first; 83 while(k != _chunk) { 84 handles_visited += chunk_oops_do(f, k, k->top()); 85 k = k->next(); 86 } 87 88 // The thread local handle areas should not get very large 89 if (TraceHandleAllocation && (size_t)handles_visited > TotalHandleAllocationLimit) { 90 #ifdef ASSERT 91 warning("%d: Visited in HandleMark : %d", 92 _nof_handlemarks, handles_visited); 93 #else 94 warning("Visited in HandleMark : %d", handles_visited); 95 #endif 96 } 97 if (_prev != NULL) _prev->oops_do(f); 98 } 99 100 void HandleMark::initialize(Thread* thread) { 101 _thread = thread; 102 // Save area 103 _area = thread->handle_area(); 104 // Save current top 105 _chunk = _area->_chunk; 106 _hwm = _area->_hwm; 107 _max = _area->_max; 108 _size_in_bytes = _area->_size_in_bytes; 109 debug_only(_area->_handle_mark_nesting++); 110 assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks"); 111 debug_only(Atomic::inc(&_nof_handlemarks);) 112 113 // Link this in the thread 114 set_previous_handle_mark(thread->last_handle_mark()); 115 thread->set_last_handle_mark(this); 116 } 117 118 119 HandleMark::~HandleMark() { 120 HandleArea* area = _area; // help compilers with poor alias analysis 121 assert(area == _thread->handle_area(), "sanity check"); 122 assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" ); 123 debug_only(area->_handle_mark_nesting--); 124 125 // Debug code to trace the number of handles allocated per mark/ 126 #ifdef ASSERT 127 if (TraceHandleAllocation) { 128 size_t handles = 0; 129 Chunk *c = _chunk->next(); 130 if (c == NULL) { 131 handles = area->_hwm - _hwm; // no new chunk allocated 132 } else { 133 handles = _max - _hwm; // add rest in first chunk 134 while(c != NULL) { 135 handles += c->length(); 136 c = c->next(); 137 } 138 handles -= area->_max - area->_hwm; // adjust for last trunk not full 139 } 140 handles /= sizeof(void *); // Adjust for size of a handle 141 if (handles > HandleAllocationLimit) { 142 // Note: _nof_handlemarks is only set in debug mode 143 warning("%d: Allocated in HandleMark : %d", _nof_handlemarks, handles); 144 } 145 146 tty->print_cr("Handles %d", handles); 147 } 148 #endif 149 150 // Delete later chunks 151 if( _chunk->next() ) { 152 // reset arena size before delete chunks. Otherwise, the total 153 // arena size could exceed total chunk size 154 assert(area->size_in_bytes() > size_in_bytes(), "Sanity check"); 155 area->set_size_in_bytes(size_in_bytes()); 156 _chunk->next_chop(); 157 } else { 158 assert(area->size_in_bytes() == size_in_bytes(), "Sanity check"); 159 } 160 // Roll back arena to saved top markers 161 area->_chunk = _chunk; 162 area->_hwm = _hwm; 163 area->_max = _max; 164 #ifdef ASSERT 165 // clear out first chunk (to detect allocation bugs) 166 if (ZapVMHandleArea) { 167 memset(_hwm, badHandleValue, _max - _hwm); 168 } 169 Atomic::dec(&_nof_handlemarks); 170 #endif 171 172 // Unlink this from the thread 173 _thread->set_last_handle_mark(previous_handle_mark()); 174 } 175 176 void* HandleMark::operator new(size_t size) throw() { 177 return AllocateHeap(size, mtThread); 178 } 179 180 void* HandleMark::operator new [] (size_t size) throw() { 181 return AllocateHeap(size, mtThread); 182 } 183 184 void HandleMark::operator delete(void* p) { 185 FreeHeap(p); 186 } 187 188 void HandleMark::operator delete[](void* p) { 189 FreeHeap(p); 190 } 191 192 #ifdef ASSERT 193 194 NoHandleMark::NoHandleMark() { 195 HandleArea* area = Thread::current()->handle_area(); 196 area->_no_handle_mark_nesting++; 197 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" ); 198 } 199 200 201 NoHandleMark::~NoHandleMark() { 202 HandleArea* area = Thread::current()->handle_area(); 203 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" ); 204 area->_no_handle_mark_nesting--; 205 } 206 207 208 ResetNoHandleMark::ResetNoHandleMark() { 209 HandleArea* area = Thread::current()->handle_area(); 210 _no_handle_mark_nesting = area->_no_handle_mark_nesting; 211 area->_no_handle_mark_nesting = 0; 212 } 213 214 215 ResetNoHandleMark::~ResetNoHandleMark() { 216 HandleArea* area = Thread::current()->handle_area(); 217 area->_no_handle_mark_nesting = _no_handle_mark_nesting; 218 } 219 220 bool instanceKlassHandle::is_instanceKlass(const Klass* k) { 221 return k->oop_is_instance(); 222 } 223 224 #endif