1 /* 2 * Copyright (c) 2005, 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 "gc/shared/collectedHeap.hpp" 27 #include "memory/universe.hpp" 28 #include "oops/oop.inline.hpp" 29 #include "runtime/thread.hpp" 30 #include "runtime/unhandledOops.hpp" 31 #include "utilities/globalDefinitions.hpp" 32 33 #ifdef CHECK_UNHANDLED_OOPS 34 const int free_list_size = 256; 35 36 37 UnhandledOops::UnhandledOops(Thread* thread) { 38 _thread = thread; 39 _oop_list = new (ResourceObj::C_HEAP, mtInternal) 40 GrowableArray<UnhandledOopEntry>(free_list_size, true); 41 _level = 0; 42 } 43 44 UnhandledOops::~UnhandledOops() { 45 delete _oop_list; 46 } 47 48 49 void UnhandledOops::dump_oops(UnhandledOops *list) { 50 for (int k = 0; k < list->_oop_list->length(); k++) { 51 UnhandledOopEntry entry = list->_oop_list->at(k); 52 tty->print(" " INTPTR_FORMAT, p2i(entry._oop_ptr)); 53 } 54 tty->cr(); 55 } 56 57 // For debugging unhandled oop detector _in the debugger_ 58 // You don't want to turn it on in compiled code here. 59 static bool unhandled_oop_print=0; 60 61 void UnhandledOops::register_unhandled_oop(oop* op, address pc) { 62 if (!_thread->is_in_stack((address)op)) 63 return; 64 65 _level ++; 66 if (unhandled_oop_print) { 67 for (int i=0; i<_level; i++) tty->print(" "); 68 tty->print_cr("r " INTPTR_FORMAT, p2i(op)); 69 } 70 UnhandledOopEntry entry(op, pc); 71 _oop_list->push(entry); 72 } 73 74 75 bool match_oop_entry(void *op, UnhandledOopEntry e) { 76 return (e.oop_ptr() == op); 77 } 78 79 // Mark unhandled oop as okay for GC - the containing struct has an oops_do and 80 // for some reason the oop has to be on the stack. 81 // May not be called for the current thread, as in the case of 82 // VM_GetOrSetLocal in jvmti. 83 void UnhandledOops::allow_unhandled_oop(oop* op) { 84 assert (CheckUnhandledOops, "should only be called with checking option"); 85 86 int i = _oop_list->find_from_end(op, match_oop_entry); 87 assert(i!=-1, "safe for gc oop not in unhandled_oop_list"); 88 89 UnhandledOopEntry entry = _oop_list->at(i); 90 assert(!entry._ok_for_gc, "duplicate entry"); 91 entry._ok_for_gc = true; 92 _oop_list->at_put(i, entry); 93 } 94 95 96 // Called by the oop destructor to remove unhandled oop from the thread's 97 // oop list. All oops given are assumed to be on the list. If not, 98 // there's a bug in the unhandled oop detector. 99 void UnhandledOops::unregister_unhandled_oop(oop* op) { 100 if (!_thread->is_in_stack((address)op)) return; 101 102 _level --; 103 if (unhandled_oop_print) { 104 for (int i=0; i<_level; i++) tty->print(" "); 105 tty->print_cr("u " INTPTR_FORMAT, p2i(op)); 106 } 107 108 int i = _oop_list->find_from_end(op, match_oop_entry); 109 assert(i!=-1, "oop not in unhandled_oop_list"); 110 _oop_list->remove_at(i); 111 } 112 113 void UnhandledOops::clear_unhandled_oops() { 114 assert (CheckUnhandledOops, "should only be called with checking option"); 115 116 for (int k = 0; k < _oop_list->length(); k++) { 117 UnhandledOopEntry entry = _oop_list->at(k); 118 // If an entry is on the unhandled oop list but isn't on the stack 119 // anymore, it must not have gotten unregistered properly and it's a bug 120 // in the unhandled oop generator. 121 if(!_thread->is_in_stack((address)entry._oop_ptr)) { 122 tty->print_cr("oop_ptr is " INTPTR_FORMAT, p2i(entry._oop_ptr)); 123 tty->print_cr("thread is " INTPTR_FORMAT " from pc " INTPTR_FORMAT, 124 p2i(_thread), p2i(entry._pc)); 125 assert(false, "heap is corrupted by the unhandled oop detector"); 126 } 127 // Set unhandled oops to a pattern that will crash distinctively 128 if (!entry._ok_for_gc) *(intptr_t*)(entry._oop_ptr) = BAD_OOP_ADDR; 129 } 130 } 131 #endif // CHECK_UNHANDLED_OOPS