0
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1 /*
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2 * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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4 *
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5 * This code is free software; you can redistribute it and/or modify it
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6 * under the terms of the GNU General Public License version 2 only, as
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7 * published by the Free Software Foundation.
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8 *
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9 * This code is distributed in the hope that it will be useful, but WITHOUT
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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12 * version 2 for more details (a copy is included in the LICENSE file that
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13 * accompanied this code).
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14 *
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15 * You should have received a copy of the GNU General Public License version
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16 * 2 along with this work; if not, write to the Free Software Foundation,
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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18 *
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19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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20 * CA 95054 USA or visit www.sun.com if you need additional information or
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21 * have any questions.
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22 *
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23 */
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24
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25 # include "incls/_precompiled.incl"
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26 # include "incls/_thread.cpp.incl"
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27
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28 #ifdef DTRACE_ENABLED
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29
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30 // Only bother with this argument setup if dtrace is available
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31
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32 HS_DTRACE_PROBE_DECL(hotspot, vm__init__begin);
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33 HS_DTRACE_PROBE_DECL(hotspot, vm__init__end);
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34 HS_DTRACE_PROBE_DECL5(hotspot, thread__start, char*, intptr_t,
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35 intptr_t, intptr_t, bool);
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36 HS_DTRACE_PROBE_DECL5(hotspot, thread__stop, char*, intptr_t,
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37 intptr_t, intptr_t, bool);
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38
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39 #define DTRACE_THREAD_PROBE(probe, javathread) \
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40 { \
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41 ResourceMark rm(this); \
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42 int len = 0; \
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43 const char* name = (javathread)->get_thread_name(); \
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44 len = strlen(name); \
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45 HS_DTRACE_PROBE5(hotspot, thread__##probe, \
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46 name, len, \
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47 java_lang_Thread::thread_id((javathread)->threadObj()), \
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48 (javathread)->osthread()->thread_id(), \
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49 java_lang_Thread::is_daemon((javathread)->threadObj())); \
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50 }
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51
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52 #else // ndef DTRACE_ENABLED
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53
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54 #define DTRACE_THREAD_PROBE(probe, javathread)
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55
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56 #endif // ndef DTRACE_ENABLED
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57
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58 // Class hierarchy
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59 // - Thread
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60 // - VMThread
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61 // - WatcherThread
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62 // - ConcurrentMarkSweepThread
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63 // - JavaThread
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64 // - CompilerThread
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65
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66 // ======= Thread ========
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67
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68 // Support for forcing alignment of thread objects for biased locking
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69 void* Thread::operator new(size_t size) {
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70 if (UseBiasedLocking) {
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71 const int alignment = markOopDesc::biased_lock_alignment;
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72 size_t aligned_size = size + (alignment - sizeof(intptr_t));
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73 void* real_malloc_addr = CHeapObj::operator new(aligned_size);
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74 void* aligned_addr = (void*) align_size_up((intptr_t) real_malloc_addr, alignment);
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75 assert(((uintptr_t) aligned_addr + (uintptr_t) size) <=
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76 ((uintptr_t) real_malloc_addr + (uintptr_t) aligned_size),
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77 "JavaThread alignment code overflowed allocated storage");
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78 if (TraceBiasedLocking) {
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79 if (aligned_addr != real_malloc_addr)
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80 tty->print_cr("Aligned thread " INTPTR_FORMAT " to " INTPTR_FORMAT,
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81 real_malloc_addr, aligned_addr);
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82 }
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83 ((Thread*) aligned_addr)->_real_malloc_address = real_malloc_addr;
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84 return aligned_addr;
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85 } else {
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86 return CHeapObj::operator new(size);
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87 }
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88 }
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89
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90 void Thread::operator delete(void* p) {
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91 if (UseBiasedLocking) {
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92 void* real_malloc_addr = ((Thread*) p)->_real_malloc_address;
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93 CHeapObj::operator delete(real_malloc_addr);
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94 } else {
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95 CHeapObj::operator delete(p);
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96 }
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97 }
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98
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99
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100 // Base class for all threads: VMThread, WatcherThread, ConcurrentMarkSweepThread,
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101 // JavaThread
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102
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103
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104 Thread::Thread() {
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105 // stack
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106 _stack_base = NULL;
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107 _stack_size = 0;
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108 _self_raw_id = 0;
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109 _lgrp_id = -1;
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110 _osthread = NULL;
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111
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112 // allocated data structures
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113 set_resource_area(new ResourceArea());
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114 set_handle_area(new HandleArea(NULL));
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115 set_active_handles(NULL);
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116 set_free_handle_block(NULL);
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117 set_last_handle_mark(NULL);
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118 set_osthread(NULL);
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119
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120 // This initial value ==> never claimed.
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121 _oops_do_parity = 0;
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122
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123 // the handle mark links itself to last_handle_mark
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124 new HandleMark(this);
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125
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126 // plain initialization
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127 debug_only(_owned_locks = NULL;)
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128 debug_only(_allow_allocation_count = 0;)
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129 NOT_PRODUCT(_allow_safepoint_count = 0;)
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130 CHECK_UNHANDLED_OOPS_ONLY(_gc_locked_out_count = 0;)
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131 _highest_lock = NULL;
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132 _jvmti_env_iteration_count = 0;
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133 _vm_operation_started_count = 0;
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134 _vm_operation_completed_count = 0;
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135 _current_pending_monitor = NULL;
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136 _current_pending_monitor_is_from_java = true;
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137 _current_waiting_monitor = NULL;
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138 _num_nested_signal = 0;
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139 omFreeList = NULL ;
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140 omFreeCount = 0 ;
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141 omFreeProvision = 32 ;
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142
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143 _SR_lock = new Monitor(Mutex::suspend_resume, "SR_lock", true);
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144 _suspend_flags = 0;
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145
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146 // thread-specific hashCode stream generator state - Marsaglia shift-xor form
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147 _hashStateX = os::random() ;
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148 _hashStateY = 842502087 ;
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149 _hashStateZ = 0x8767 ; // (int)(3579807591LL & 0xffff) ;
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150 _hashStateW = 273326509 ;
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151
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152 _OnTrap = 0 ;
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153 _schedctl = NULL ;
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154 _Stalled = 0 ;
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155 _TypeTag = 0x2BAD ;
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156
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157 // Many of the following fields are effectively final - immutable
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158 // Note that nascent threads can't use the Native Monitor-Mutex
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159 // construct until the _MutexEvent is initialized ...
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160 // CONSIDER: instead of using a fixed set of purpose-dedicated ParkEvents
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161 // we might instead use a stack of ParkEvents that we could provision on-demand.
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162 // The stack would act as a cache to avoid calls to ParkEvent::Allocate()
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163 // and ::Release()
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164 _ParkEvent = ParkEvent::Allocate (this) ;
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165 _SleepEvent = ParkEvent::Allocate (this) ;
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166 _MutexEvent = ParkEvent::Allocate (this) ;
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167 _MuxEvent = ParkEvent::Allocate (this) ;
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168
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169 #ifdef CHECK_UNHANDLED_OOPS
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170 if (CheckUnhandledOops) {
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171 _unhandled_oops = new UnhandledOops(this);
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172 }
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173 #endif // CHECK_UNHANDLED_OOPS
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174 #ifdef ASSERT
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175 if (UseBiasedLocking) {
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176 assert((((uintptr_t) this) & (markOopDesc::biased_lock_alignment - 1)) == 0, "forced alignment of thread object failed");
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177 assert(this == _real_malloc_address ||
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178 this == (void*) align_size_up((intptr_t) _real_malloc_address, markOopDesc::biased_lock_alignment),
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179 "bug in forced alignment of thread objects");
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180 }
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181 #endif /* ASSERT */
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182 }
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183
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184 void Thread::initialize_thread_local_storage() {
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185 // Note: Make sure this method only calls
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186 // non-blocking operations. Otherwise, it might not work
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187 // with the thread-startup/safepoint interaction.
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188
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189 // During Java thread startup, safepoint code should allow this
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190 // method to complete because it may need to allocate memory to
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191 // store information for the new thread.
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192
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193 // initialize structure dependent on thread local storage
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194 ThreadLocalStorage::set_thread(this);
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195
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196 // set up any platform-specific state.
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197 os::initialize_thread();
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198
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199 }
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200
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201 void Thread::record_stack_base_and_size() {
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202 set_stack_base(os::current_stack_base());
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203 set_stack_size(os::current_stack_size());
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204 }
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205
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206
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207 Thread::~Thread() {
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208 // Reclaim the objectmonitors from the omFreeList of the moribund thread.
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209 ObjectSynchronizer::omFlush (this) ;
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210
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211 // deallocate data structures
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212 delete resource_area();
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213 // since the handle marks are using the handle area, we have to deallocated the root
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214 // handle mark before deallocating the thread's handle area,
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215 assert(last_handle_mark() != NULL, "check we have an element");
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216 delete last_handle_mark();
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217 assert(last_handle_mark() == NULL, "check we have reached the end");
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218
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219 // It's possible we can encounter a null _ParkEvent, etc., in stillborn threads.
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220 // We NULL out the fields for good hygiene.
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221 ParkEvent::Release (_ParkEvent) ; _ParkEvent = NULL ;
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222 ParkEvent::Release (_SleepEvent) ; _SleepEvent = NULL ;
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223 ParkEvent::Release (_MutexEvent) ; _MutexEvent = NULL ;
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224 ParkEvent::Release (_MuxEvent) ; _MuxEvent = NULL ;
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225
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226 delete handle_area();
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227
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228 // osthread() can be NULL, if creation of thread failed.
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229 if (osthread() != NULL) os::free_thread(osthread());
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230
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231 delete _SR_lock;
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232
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233 // clear thread local storage if the Thread is deleting itself
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234 if (this == Thread::current()) {
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235 ThreadLocalStorage::set_thread(NULL);
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236 } else {
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237 // In the case where we're not the current thread, invalidate all the
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238 // caches in case some code tries to get the current thread or the
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239 // thread that was destroyed, and gets stale information.
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240 ThreadLocalStorage::invalidate_all();
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241 }
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242 CHECK_UNHANDLED_OOPS_ONLY(if (CheckUnhandledOops) delete unhandled_oops();)
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243 }
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244
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245 // NOTE: dummy function for assertion purpose.
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246 void Thread::run() {
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247 ShouldNotReachHere();
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248 }
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249
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250 #ifdef ASSERT
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251 // Private method to check for dangling thread pointer
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252 void check_for_dangling_thread_pointer(Thread *thread) {
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253 assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
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254 "possibility of dangling Thread pointer");
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255 }
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256 #endif
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257
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258
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259 #ifndef PRODUCT
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260 // Tracing method for basic thread operations
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261 void Thread::trace(const char* msg, const Thread* const thread) {
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262 if (!TraceThreadEvents) return;
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263 ResourceMark rm;
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264 ThreadCritical tc;
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265 const char *name = "non-Java thread";
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266 int prio = -1;
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267 if (thread->is_Java_thread()
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268 && !thread->is_Compiler_thread()) {
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269 // The Threads_lock must be held to get information about
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270 // this thread but may not be in some situations when
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271 // tracing thread events.
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272 bool release_Threads_lock = false;
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273 if (!Threads_lock->owned_by_self()) {
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274 Threads_lock->lock();
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275 release_Threads_lock = true;
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276 }
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277 JavaThread* jt = (JavaThread *)thread;
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278 name = (char *)jt->get_thread_name();
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279 oop thread_oop = jt->threadObj();
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280 if (thread_oop != NULL) {
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281 prio = java_lang_Thread::priority(thread_oop);
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282 }
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283 if (release_Threads_lock) {
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284 Threads_lock->unlock();
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285 }
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286 }
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287 tty->print_cr("Thread::%s " INTPTR_FORMAT " [%lx] %s (prio: %d)", msg, thread, thread->osthread()->thread_id(), name, prio);
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288 }
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289 #endif
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290
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291
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292 ThreadPriority Thread::get_priority(const Thread* const thread) {
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293 trace("get priority", thread);
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294 ThreadPriority priority;
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295 // Can return an error!
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296 (void)os::get_priority(thread, priority);
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297 assert(MinPriority <= priority && priority <= MaxPriority, "non-Java priority found");
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298 return priority;
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299 }
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300
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301 void Thread::set_priority(Thread* thread, ThreadPriority priority) {
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302 trace("set priority", thread);
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303 debug_only(check_for_dangling_thread_pointer(thread);)
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304 // Can return an error!
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305 (void)os::set_priority(thread, priority);
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306 }
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307
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308
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309 void Thread::start(Thread* thread) {
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310 trace("start", thread);
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311 // Start is different from resume in that its safety is guaranteed by context or
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312 // being called from a Java method synchronized on the Thread object.
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313 if (!DisableStartThread) {
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314 if (thread->is_Java_thread()) {
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315 // Initialize the thread state to RUNNABLE before starting this thread.
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316 // Can not set it after the thread started because we do not know the
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317 // exact thread state at that time. It could be in MONITOR_WAIT or
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318 // in SLEEPING or some other state.
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319 java_lang_Thread::set_thread_status(((JavaThread*)thread)->threadObj(),
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320 java_lang_Thread::RUNNABLE);
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321 }
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322 os::start_thread(thread);
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323 }
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324 }
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325
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326 // Enqueue a VM_Operation to do the job for us - sometime later
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327 void Thread::send_async_exception(oop java_thread, oop java_throwable) {
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328 VM_ThreadStop* vm_stop = new VM_ThreadStop(java_thread, java_throwable);
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329 VMThread::execute(vm_stop);
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330 }
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331
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332
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333 //
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334 // Check if an external suspend request has completed (or has been
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335 // cancelled). Returns true if the thread is externally suspended and
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336 // false otherwise.
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337 //
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338 // The bits parameter returns information about the code path through
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339 // the routine. Useful for debugging:
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340 //
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341 // set in is_ext_suspend_completed():
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342 // 0x00000001 - routine was entered
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343 // 0x00000010 - routine return false at end
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344 // 0x00000100 - thread exited (return false)
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345 // 0x00000200 - suspend request cancelled (return false)
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346 // 0x00000400 - thread suspended (return true)
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347 // 0x00001000 - thread is in a suspend equivalent state (return true)
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348 // 0x00002000 - thread is native and walkable (return true)
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349 // 0x00004000 - thread is native_trans and walkable (needed retry)
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350 //
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351 // set in wait_for_ext_suspend_completion():
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352 // 0x00010000 - routine was entered
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353 // 0x00020000 - suspend request cancelled before loop (return false)
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354 // 0x00040000 - thread suspended before loop (return true)
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355 // 0x00080000 - suspend request cancelled in loop (return false)
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356 // 0x00100000 - thread suspended in loop (return true)
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357 // 0x00200000 - suspend not completed during retry loop (return false)
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358 //
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359
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360 // Helper class for tracing suspend wait debug bits.
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361 //
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362 // 0x00000100 indicates that the target thread exited before it could
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363 // self-suspend which is not a wait failure. 0x00000200, 0x00020000 and
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364 // 0x00080000 each indicate a cancelled suspend request so they don't
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365 // count as wait failures either.
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366 #define DEBUG_FALSE_BITS (0x00000010 | 0x00200000)
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367
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368 class TraceSuspendDebugBits : public StackObj {
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369 private:
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370 JavaThread * jt;
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371 bool is_wait;
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372 bool called_by_wait; // meaningful when !is_wait
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373 uint32_t * bits;
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374
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375 public:
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376 TraceSuspendDebugBits(JavaThread *_jt, bool _is_wait, bool _called_by_wait,
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377 uint32_t *_bits) {
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378 jt = _jt;
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379 is_wait = _is_wait;
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380 called_by_wait = _called_by_wait;
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381 bits = _bits;
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382 }
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383
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384 ~TraceSuspendDebugBits() {
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385 if (!is_wait) {
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386 #if 1
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387 // By default, don't trace bits for is_ext_suspend_completed() calls.
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388 // That trace is very chatty.
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389 return;
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390 #else
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391 if (!called_by_wait) {
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392 // If tracing for is_ext_suspend_completed() is enabled, then only
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393 // trace calls to it from wait_for_ext_suspend_completion()
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394 return;
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395 }
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396 #endif
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397 }
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398
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399 if (AssertOnSuspendWaitFailure || TraceSuspendWaitFailures) {
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400 if (bits != NULL && (*bits & DEBUG_FALSE_BITS) != 0) {
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401 MutexLocker ml(Threads_lock); // needed for get_thread_name()
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402 ResourceMark rm;
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403
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404 tty->print_cr(
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405 "Failed wait_for_ext_suspend_completion(thread=%s, debug_bits=%x)",
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406 jt->get_thread_name(), *bits);
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407
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408 guarantee(!AssertOnSuspendWaitFailure, "external suspend wait failed");
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409 }
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410 }
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411 }
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412 };
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413 #undef DEBUG_FALSE_BITS
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414
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415
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416 bool JavaThread::is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits) {
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417 TraceSuspendDebugBits tsdb(this, false /* !is_wait */, called_by_wait, bits);
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418
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419 bool did_trans_retry = false; // only do thread_in_native_trans retry once
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420 bool do_trans_retry; // flag to force the retry
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421
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422 *bits |= 0x00000001;
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423
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424 do {
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425 do_trans_retry = false;
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426
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427 if (is_exiting()) {
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428 // Thread is in the process of exiting. This is always checked
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429 // first to reduce the risk of dereferencing a freed JavaThread.
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430 *bits |= 0x00000100;
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431 return false;
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432 }
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433
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434 if (!is_external_suspend()) {
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435 // Suspend request is cancelled. This is always checked before
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436 // is_ext_suspended() to reduce the risk of a rogue resume
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437 // confusing the thread that made the suspend request.
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438 *bits |= 0x00000200;
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439 return false;
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440 }
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441
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442 if (is_ext_suspended()) {
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443 // thread is suspended
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444 *bits |= 0x00000400;
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445 return true;
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446 }
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447
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448 // Now that we no longer do hard suspends of threads running
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449 // native code, the target thread can be changing thread state
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450 // while we are in this routine:
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451 //
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452 // _thread_in_native -> _thread_in_native_trans -> _thread_blocked
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453 //
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454 // We save a copy of the thread state as observed at this moment
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455 // and make our decision about suspend completeness based on the
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456 // copy. This closes the race where the thread state is seen as
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457 // _thread_in_native_trans in the if-thread_blocked check, but is
|
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458 // seen as _thread_blocked in if-thread_in_native_trans check.
|
|
459 JavaThreadState save_state = thread_state();
|
|
460
|
|
461 if (save_state == _thread_blocked && is_suspend_equivalent()) {
|
|
462 // If the thread's state is _thread_blocked and this blocking
|
|
463 // condition is known to be equivalent to a suspend, then we can
|
|
464 // consider the thread to be externally suspended. This means that
|
|
465 // the code that sets _thread_blocked has been modified to do
|
|
466 // self-suspension if the blocking condition releases. We also
|
|
467 // used to check for CONDVAR_WAIT here, but that is now covered by
|
|
468 // the _thread_blocked with self-suspension check.
|
|
469 //
|
|
470 // Return true since we wouldn't be here unless there was still an
|
|
471 // external suspend request.
|
|
472 *bits |= 0x00001000;
|
|
473 return true;
|
|
474 } else if (save_state == _thread_in_native && frame_anchor()->walkable()) {
|
|
475 // Threads running native code will self-suspend on native==>VM/Java
|
|
476 // transitions. If its stack is walkable (should always be the case
|
|
477 // unless this function is called before the actual java_suspend()
|
|
478 // call), then the wait is done.
|
|
479 *bits |= 0x00002000;
|
|
480 return true;
|
|
481 } else if (!called_by_wait && !did_trans_retry &&
|
|
482 save_state == _thread_in_native_trans &&
|
|
483 frame_anchor()->walkable()) {
|
|
484 // The thread is transitioning from thread_in_native to another
|
|
485 // thread state. check_safepoint_and_suspend_for_native_trans()
|
|
486 // will force the thread to self-suspend. If it hasn't gotten
|
|
487 // there yet we may have caught the thread in-between the native
|
|
488 // code check above and the self-suspend. Lucky us. If we were
|
|
489 // called by wait_for_ext_suspend_completion(), then it
|
|
490 // will be doing the retries so we don't have to.
|
|
491 //
|
|
492 // Since we use the saved thread state in the if-statement above,
|
|
493 // there is a chance that the thread has already transitioned to
|
|
494 // _thread_blocked by the time we get here. In that case, we will
|
|
495 // make a single unnecessary pass through the logic below. This
|
|
496 // doesn't hurt anything since we still do the trans retry.
|
|
497
|
|
498 *bits |= 0x00004000;
|
|
499
|
|
500 // Once the thread leaves thread_in_native_trans for another
|
|
501 // thread state, we break out of this retry loop. We shouldn't
|
|
502 // need this flag to prevent us from getting back here, but
|
|
503 // sometimes paranoia is good.
|
|
504 did_trans_retry = true;
|
|
505
|
|
506 // We wait for the thread to transition to a more usable state.
|
|
507 for (int i = 1; i <= SuspendRetryCount; i++) {
|
|
508 // We used to do an "os::yield_all(i)" call here with the intention
|
|
509 // that yielding would increase on each retry. However, the parameter
|
|
510 // is ignored on Linux which means the yield didn't scale up. Waiting
|
|
511 // on the SR_lock below provides a much more predictable scale up for
|
|
512 // the delay. It also provides a simple/direct point to check for any
|
|
513 // safepoint requests from the VMThread
|
|
514
|
|
515 // temporarily drops SR_lock while doing wait with safepoint check
|
|
516 // (if we're a JavaThread - the WatcherThread can also call this)
|
|
517 // and increase delay with each retry
|
|
518 SR_lock()->wait(!Thread::current()->is_Java_thread(), i * delay);
|
|
519
|
|
520 // check the actual thread state instead of what we saved above
|
|
521 if (thread_state() != _thread_in_native_trans) {
|
|
522 // the thread has transitioned to another thread state so
|
|
523 // try all the checks (except this one) one more time.
|
|
524 do_trans_retry = true;
|
|
525 break;
|
|
526 }
|
|
527 } // end retry loop
|
|
528
|
|
529
|
|
530 }
|
|
531 } while (do_trans_retry);
|
|
532
|
|
533 *bits |= 0x00000010;
|
|
534 return false;
|
|
535 }
|
|
536
|
|
537 //
|
|
538 // Wait for an external suspend request to complete (or be cancelled).
|
|
539 // Returns true if the thread is externally suspended and false otherwise.
|
|
540 //
|
|
541 bool JavaThread::wait_for_ext_suspend_completion(int retries, int delay,
|
|
542 uint32_t *bits) {
|
|
543 TraceSuspendDebugBits tsdb(this, true /* is_wait */,
|
|
544 false /* !called_by_wait */, bits);
|
|
545
|
|
546 // local flag copies to minimize SR_lock hold time
|
|
547 bool is_suspended;
|
|
548 bool pending;
|
|
549 uint32_t reset_bits;
|
|
550
|
|
551 // set a marker so is_ext_suspend_completed() knows we are the caller
|
|
552 *bits |= 0x00010000;
|
|
553
|
|
554 // We use reset_bits to reinitialize the bits value at the top of
|
|
555 // each retry loop. This allows the caller to make use of any
|
|
556 // unused bits for their own marking purposes.
|
|
557 reset_bits = *bits;
|
|
558
|
|
559 {
|
|
560 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
561 is_suspended = is_ext_suspend_completed(true /* called_by_wait */,
|
|
562 delay, bits);
|
|
563 pending = is_external_suspend();
|
|
564 }
|
|
565 // must release SR_lock to allow suspension to complete
|
|
566
|
|
567 if (!pending) {
|
|
568 // A cancelled suspend request is the only false return from
|
|
569 // is_ext_suspend_completed() that keeps us from entering the
|
|
570 // retry loop.
|
|
571 *bits |= 0x00020000;
|
|
572 return false;
|
|
573 }
|
|
574
|
|
575 if (is_suspended) {
|
|
576 *bits |= 0x00040000;
|
|
577 return true;
|
|
578 }
|
|
579
|
|
580 for (int i = 1; i <= retries; i++) {
|
|
581 *bits = reset_bits; // reinit to only track last retry
|
|
582
|
|
583 // We used to do an "os::yield_all(i)" call here with the intention
|
|
584 // that yielding would increase on each retry. However, the parameter
|
|
585 // is ignored on Linux which means the yield didn't scale up. Waiting
|
|
586 // on the SR_lock below provides a much more predictable scale up for
|
|
587 // the delay. It also provides a simple/direct point to check for any
|
|
588 // safepoint requests from the VMThread
|
|
589
|
|
590 {
|
|
591 MutexLocker ml(SR_lock());
|
|
592 // wait with safepoint check (if we're a JavaThread - the WatcherThread
|
|
593 // can also call this) and increase delay with each retry
|
|
594 SR_lock()->wait(!Thread::current()->is_Java_thread(), i * delay);
|
|
595
|
|
596 is_suspended = is_ext_suspend_completed(true /* called_by_wait */,
|
|
597 delay, bits);
|
|
598
|
|
599 // It is possible for the external suspend request to be cancelled
|
|
600 // (by a resume) before the actual suspend operation is completed.
|
|
601 // Refresh our local copy to see if we still need to wait.
|
|
602 pending = is_external_suspend();
|
|
603 }
|
|
604
|
|
605 if (!pending) {
|
|
606 // A cancelled suspend request is the only false return from
|
|
607 // is_ext_suspend_completed() that keeps us from staying in the
|
|
608 // retry loop.
|
|
609 *bits |= 0x00080000;
|
|
610 return false;
|
|
611 }
|
|
612
|
|
613 if (is_suspended) {
|
|
614 *bits |= 0x00100000;
|
|
615 return true;
|
|
616 }
|
|
617 } // end retry loop
|
|
618
|
|
619 // thread did not suspend after all our retries
|
|
620 *bits |= 0x00200000;
|
|
621 return false;
|
|
622 }
|
|
623
|
|
624 #ifndef PRODUCT
|
|
625 void JavaThread::record_jump(address target, address instr, const char* file, int line) {
|
|
626
|
|
627 // This should not need to be atomic as the only way for simultaneous
|
|
628 // updates is via interrupts. Even then this should be rare or non-existant
|
|
629 // and we don't care that much anyway.
|
|
630
|
|
631 int index = _jmp_ring_index;
|
|
632 _jmp_ring_index = (index + 1 ) & (jump_ring_buffer_size - 1);
|
|
633 _jmp_ring[index]._target = (intptr_t) target;
|
|
634 _jmp_ring[index]._instruction = (intptr_t) instr;
|
|
635 _jmp_ring[index]._file = file;
|
|
636 _jmp_ring[index]._line = line;
|
|
637 }
|
|
638 #endif /* PRODUCT */
|
|
639
|
|
640 // Called by flat profiler
|
|
641 // Callers have already called wait_for_ext_suspend_completion
|
|
642 // The assertion for that is currently too complex to put here:
|
|
643 bool JavaThread::profile_last_Java_frame(frame* _fr) {
|
|
644 bool gotframe = false;
|
|
645 // self suspension saves needed state.
|
|
646 if (has_last_Java_frame() && _anchor.walkable()) {
|
|
647 *_fr = pd_last_frame();
|
|
648 gotframe = true;
|
|
649 }
|
|
650 return gotframe;
|
|
651 }
|
|
652
|
|
653 void Thread::interrupt(Thread* thread) {
|
|
654 trace("interrupt", thread);
|
|
655 debug_only(check_for_dangling_thread_pointer(thread);)
|
|
656 os::interrupt(thread);
|
|
657 }
|
|
658
|
|
659 bool Thread::is_interrupted(Thread* thread, bool clear_interrupted) {
|
|
660 trace("is_interrupted", thread);
|
|
661 debug_only(check_for_dangling_thread_pointer(thread);)
|
|
662 // Note: If clear_interrupted==false, this simply fetches and
|
|
663 // returns the value of the field osthread()->interrupted().
|
|
664 return os::is_interrupted(thread, clear_interrupted);
|
|
665 }
|
|
666
|
|
667
|
|
668 // GC Support
|
|
669 bool Thread::claim_oops_do_par_case(int strong_roots_parity) {
|
|
670 jint thread_parity = _oops_do_parity;
|
|
671 if (thread_parity != strong_roots_parity) {
|
|
672 jint res = Atomic::cmpxchg(strong_roots_parity, &_oops_do_parity, thread_parity);
|
|
673 if (res == thread_parity) return true;
|
|
674 else {
|
|
675 guarantee(res == strong_roots_parity, "Or else what?");
|
|
676 assert(SharedHeap::heap()->n_par_threads() > 0,
|
|
677 "Should only fail when parallel.");
|
|
678 return false;
|
|
679 }
|
|
680 }
|
|
681 assert(SharedHeap::heap()->n_par_threads() > 0,
|
|
682 "Should only fail when parallel.");
|
|
683 return false;
|
|
684 }
|
|
685
|
|
686 void Thread::oops_do(OopClosure* f) {
|
|
687 active_handles()->oops_do(f);
|
|
688 // Do oop for ThreadShadow
|
|
689 f->do_oop((oop*)&_pending_exception);
|
|
690 handle_area()->oops_do(f);
|
|
691 }
|
|
692
|
|
693 void Thread::nmethods_do() {
|
|
694 }
|
|
695
|
|
696 void Thread::print_on(outputStream* st) const {
|
|
697 // get_priority assumes osthread initialized
|
|
698 if (osthread() != NULL) {
|
|
699 st->print("prio=%d tid=" INTPTR_FORMAT " ", get_priority(this), this);
|
|
700 osthread()->print_on(st);
|
|
701 }
|
|
702 debug_only(if (WizardMode) print_owned_locks_on(st);)
|
|
703 }
|
|
704
|
|
705 // Thread::print_on_error() is called by fatal error handler. Don't use
|
|
706 // any lock or allocate memory.
|
|
707 void Thread::print_on_error(outputStream* st, char* buf, int buflen) const {
|
|
708 if (is_VM_thread()) st->print("VMThread");
|
|
709 else if (is_Compiler_thread()) st->print("CompilerThread");
|
|
710 else if (is_Java_thread()) st->print("JavaThread");
|
|
711 else if (is_GC_task_thread()) st->print("GCTaskThread");
|
|
712 else if (is_Watcher_thread()) st->print("WatcherThread");
|
|
713 else if (is_ConcurrentGC_thread()) st->print("ConcurrentGCThread");
|
|
714 else st->print("Thread");
|
|
715
|
|
716 st->print(" [stack: " PTR_FORMAT "," PTR_FORMAT "]",
|
|
717 _stack_base - _stack_size, _stack_base);
|
|
718
|
|
719 if (osthread()) {
|
|
720 st->print(" [id=%d]", osthread()->thread_id());
|
|
721 }
|
|
722 }
|
|
723
|
|
724 #ifdef ASSERT
|
|
725 void Thread::print_owned_locks_on(outputStream* st) const {
|
|
726 Monitor *cur = _owned_locks;
|
|
727 if (cur == NULL) {
|
|
728 st->print(" (no locks) ");
|
|
729 } else {
|
|
730 st->print_cr(" Locks owned:");
|
|
731 while(cur) {
|
|
732 cur->print_on(st);
|
|
733 cur = cur->next();
|
|
734 }
|
|
735 }
|
|
736 }
|
|
737
|
|
738 static int ref_use_count = 0;
|
|
739
|
|
740 bool Thread::owns_locks_but_compiled_lock() const {
|
|
741 for(Monitor *cur = _owned_locks; cur; cur = cur->next()) {
|
|
742 if (cur != Compile_lock) return true;
|
|
743 }
|
|
744 return false;
|
|
745 }
|
|
746
|
|
747
|
|
748 #endif
|
|
749
|
|
750 #ifndef PRODUCT
|
|
751
|
|
752 // The flag: potential_vm_operation notifies if this particular safepoint state could potential
|
|
753 // invoke the vm-thread (i.e., and oop allocation). In that case, we also have to make sure that
|
|
754 // no threads which allow_vm_block's are held
|
|
755 void Thread::check_for_valid_safepoint_state(bool potential_vm_operation) {
|
|
756 // Check if current thread is allowed to block at a safepoint
|
|
757 if (!(_allow_safepoint_count == 0))
|
|
758 fatal("Possible safepoint reached by thread that does not allow it");
|
|
759 if (is_Java_thread() && ((JavaThread*)this)->thread_state() != _thread_in_vm) {
|
|
760 fatal("LEAF method calling lock?");
|
|
761 }
|
|
762
|
|
763 #ifdef ASSERT
|
|
764 if (potential_vm_operation && is_Java_thread()
|
|
765 && !Universe::is_bootstrapping()) {
|
|
766 // Make sure we do not hold any locks that the VM thread also uses.
|
|
767 // This could potentially lead to deadlocks
|
|
768 for(Monitor *cur = _owned_locks; cur; cur = cur->next()) {
|
|
769 // Threads_lock is special, since the safepoint synchronization will not start before this is
|
|
770 // acquired. Hence, a JavaThread cannot be holding it at a safepoint. So is VMOperationRequest_lock,
|
|
771 // since it is used to transfer control between JavaThreads and the VMThread
|
|
772 // Do not *exclude* any locks unless you are absolutly sure it is correct. Ask someone else first!
|
|
773 if ( (cur->allow_vm_block() &&
|
|
774 cur != Threads_lock &&
|
|
775 cur != Compile_lock && // Temporary: should not be necessary when we get spearate compilation
|
|
776 cur != VMOperationRequest_lock &&
|
|
777 cur != VMOperationQueue_lock) ||
|
|
778 cur->rank() == Mutex::special) {
|
|
779 warning("Thread holding lock at safepoint that vm can block on: %s", cur->name());
|
|
780 }
|
|
781 }
|
|
782 }
|
|
783
|
|
784 if (GCALotAtAllSafepoints) {
|
|
785 // We could enter a safepoint here and thus have a gc
|
|
786 InterfaceSupport::check_gc_alot();
|
|
787 }
|
|
788
|
|
789 #endif
|
|
790 }
|
|
791 #endif
|
|
792
|
|
793 bool Thread::lock_is_in_stack(address adr) const {
|
|
794 assert(Thread::current() == this, "lock_is_in_stack can only be called from current thread");
|
|
795 // High limit: highest_lock is set during thread execution
|
|
796 // Low limit: address of the local variable dummy, rounded to 4K boundary.
|
|
797 // (The rounding helps finding threads in unsafe mode, even if the particular stack
|
|
798 // frame has been popped already. Correct as long as stacks are at least 4K long and aligned.)
|
|
799 address end = os::current_stack_pointer();
|
|
800 if (_highest_lock >= adr && adr >= end) return true;
|
|
801
|
|
802 return false;
|
|
803 }
|
|
804
|
|
805
|
|
806 bool Thread::is_in_stack(address adr) const {
|
|
807 assert(Thread::current() == this, "is_in_stack can only be called from current thread");
|
|
808 address end = os::current_stack_pointer();
|
|
809 if (stack_base() >= adr && adr >= end) return true;
|
|
810
|
|
811 return false;
|
|
812 }
|
|
813
|
|
814
|
|
815 // We had to move these methods here, because vm threads get into ObjectSynchronizer::enter
|
|
816 // However, there is a note in JavaThread::is_lock_owned() about the VM threads not being
|
|
817 // used for compilation in the future. If that change is made, the need for these methods
|
|
818 // should be revisited, and they should be removed if possible.
|
|
819
|
|
820 bool Thread::is_lock_owned(address adr) const {
|
|
821 if (lock_is_in_stack(adr) ) return true;
|
|
822 return false;
|
|
823 }
|
|
824
|
|
825 bool Thread::set_as_starting_thread() {
|
|
826 // NOTE: this must be called inside the main thread.
|
|
827 return os::create_main_thread((JavaThread*)this);
|
|
828 }
|
|
829
|
|
830 static void initialize_class(symbolHandle class_name, TRAPS) {
|
|
831 klassOop klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK);
|
|
832 instanceKlass::cast(klass)->initialize(CHECK);
|
|
833 }
|
|
834
|
|
835
|
|
836 // Creates the initial ThreadGroup
|
|
837 static Handle create_initial_thread_group(TRAPS) {
|
|
838 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_ThreadGroup(), true, CHECK_NH);
|
|
839 instanceKlassHandle klass (THREAD, k);
|
|
840
|
|
841 Handle system_instance = klass->allocate_instance_handle(CHECK_NH);
|
|
842 {
|
|
843 JavaValue result(T_VOID);
|
|
844 JavaCalls::call_special(&result,
|
|
845 system_instance,
|
|
846 klass,
|
|
847 vmSymbolHandles::object_initializer_name(),
|
|
848 vmSymbolHandles::void_method_signature(),
|
|
849 CHECK_NH);
|
|
850 }
|
|
851 Universe::set_system_thread_group(system_instance());
|
|
852
|
|
853 Handle main_instance = klass->allocate_instance_handle(CHECK_NH);
|
|
854 {
|
|
855 JavaValue result(T_VOID);
|
|
856 Handle string = java_lang_String::create_from_str("main", CHECK_NH);
|
|
857 JavaCalls::call_special(&result,
|
|
858 main_instance,
|
|
859 klass,
|
|
860 vmSymbolHandles::object_initializer_name(),
|
|
861 vmSymbolHandles::threadgroup_string_void_signature(),
|
|
862 system_instance,
|
|
863 string,
|
|
864 CHECK_NH);
|
|
865 }
|
|
866 return main_instance;
|
|
867 }
|
|
868
|
|
869 // Creates the initial Thread
|
|
870 static oop create_initial_thread(Handle thread_group, JavaThread* thread, TRAPS) {
|
|
871 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_Thread(), true, CHECK_NULL);
|
|
872 instanceKlassHandle klass (THREAD, k);
|
|
873 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_NULL);
|
|
874
|
|
875 java_lang_Thread::set_thread(thread_oop(), thread);
|
|
876 java_lang_Thread::set_priority(thread_oop(), NormPriority);
|
|
877 thread->set_threadObj(thread_oop());
|
|
878
|
|
879 Handle string = java_lang_String::create_from_str("main", CHECK_NULL);
|
|
880
|
|
881 JavaValue result(T_VOID);
|
|
882 JavaCalls::call_special(&result, thread_oop,
|
|
883 klass,
|
|
884 vmSymbolHandles::object_initializer_name(),
|
|
885 vmSymbolHandles::threadgroup_string_void_signature(),
|
|
886 thread_group,
|
|
887 string,
|
|
888 CHECK_NULL);
|
|
889 return thread_oop();
|
|
890 }
|
|
891
|
|
892 static void call_initializeSystemClass(TRAPS) {
|
|
893 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_System(), true, CHECK);
|
|
894 instanceKlassHandle klass (THREAD, k);
|
|
895
|
|
896 JavaValue result(T_VOID);
|
|
897 JavaCalls::call_static(&result, klass, vmSymbolHandles::initializeSystemClass_name(),
|
|
898 vmSymbolHandles::void_method_signature(), CHECK);
|
|
899 }
|
|
900
|
|
901 static void reset_vm_info_property(TRAPS) {
|
|
902 // the vm info string
|
|
903 ResourceMark rm(THREAD);
|
|
904 const char *vm_info = VM_Version::vm_info_string();
|
|
905
|
|
906 // java.lang.System class
|
|
907 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_System(), true, CHECK);
|
|
908 instanceKlassHandle klass (THREAD, k);
|
|
909
|
|
910 // setProperty arguments
|
|
911 Handle key_str = java_lang_String::create_from_str("java.vm.info", CHECK);
|
|
912 Handle value_str = java_lang_String::create_from_str(vm_info, CHECK);
|
|
913
|
|
914 // return value
|
|
915 JavaValue r(T_OBJECT);
|
|
916
|
|
917 // public static String setProperty(String key, String value);
|
|
918 JavaCalls::call_static(&r,
|
|
919 klass,
|
|
920 vmSymbolHandles::setProperty_name(),
|
|
921 vmSymbolHandles::string_string_string_signature(),
|
|
922 key_str,
|
|
923 value_str,
|
|
924 CHECK);
|
|
925 }
|
|
926
|
|
927
|
|
928 void JavaThread::allocate_threadObj(Handle thread_group, char* thread_name, bool daemon, TRAPS) {
|
|
929 assert(thread_group.not_null(), "thread group should be specified");
|
|
930 assert(threadObj() == NULL, "should only create Java thread object once");
|
|
931
|
|
932 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_Thread(), true, CHECK);
|
|
933 instanceKlassHandle klass (THREAD, k);
|
|
934 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
|
|
935
|
|
936 java_lang_Thread::set_thread(thread_oop(), this);
|
|
937 java_lang_Thread::set_priority(thread_oop(), NormPriority);
|
|
938 set_threadObj(thread_oop());
|
|
939
|
|
940 JavaValue result(T_VOID);
|
|
941 if (thread_name != NULL) {
|
|
942 Handle name = java_lang_String::create_from_str(thread_name, CHECK);
|
|
943 // Thread gets assigned specified name and null target
|
|
944 JavaCalls::call_special(&result,
|
|
945 thread_oop,
|
|
946 klass,
|
|
947 vmSymbolHandles::object_initializer_name(),
|
|
948 vmSymbolHandles::threadgroup_string_void_signature(),
|
|
949 thread_group, // Argument 1
|
|
950 name, // Argument 2
|
|
951 THREAD);
|
|
952 } else {
|
|
953 // Thread gets assigned name "Thread-nnn" and null target
|
|
954 // (java.lang.Thread doesn't have a constructor taking only a ThreadGroup argument)
|
|
955 JavaCalls::call_special(&result,
|
|
956 thread_oop,
|
|
957 klass,
|
|
958 vmSymbolHandles::object_initializer_name(),
|
|
959 vmSymbolHandles::threadgroup_runnable_void_signature(),
|
|
960 thread_group, // Argument 1
|
|
961 Handle(), // Argument 2
|
|
962 THREAD);
|
|
963 }
|
|
964
|
|
965
|
|
966 if (daemon) {
|
|
967 java_lang_Thread::set_daemon(thread_oop());
|
|
968 }
|
|
969
|
|
970 if (HAS_PENDING_EXCEPTION) {
|
|
971 return;
|
|
972 }
|
|
973
|
|
974 KlassHandle group(this, SystemDictionary::threadGroup_klass());
|
|
975 Handle threadObj(this, this->threadObj());
|
|
976
|
|
977 JavaCalls::call_special(&result,
|
|
978 thread_group,
|
|
979 group,
|
|
980 vmSymbolHandles::add_method_name(),
|
|
981 vmSymbolHandles::thread_void_signature(),
|
|
982 threadObj, // Arg 1
|
|
983 THREAD);
|
|
984
|
|
985
|
|
986 }
|
|
987
|
|
988 // NamedThread -- non-JavaThread subclasses with multiple
|
|
989 // uniquely named instances should derive from this.
|
|
990 NamedThread::NamedThread() : Thread() {
|
|
991 _name = NULL;
|
|
992 }
|
|
993
|
|
994 NamedThread::~NamedThread() {
|
|
995 if (_name != NULL) {
|
|
996 FREE_C_HEAP_ARRAY(char, _name);
|
|
997 _name = NULL;
|
|
998 }
|
|
999 }
|
|
1000
|
|
1001 void NamedThread::set_name(const char* format, ...) {
|
|
1002 guarantee(_name == NULL, "Only get to set name once.");
|
|
1003 _name = NEW_C_HEAP_ARRAY(char, max_name_len);
|
|
1004 guarantee(_name != NULL, "alloc failure");
|
|
1005 va_list ap;
|
|
1006 va_start(ap, format);
|
|
1007 jio_vsnprintf(_name, max_name_len, format, ap);
|
|
1008 va_end(ap);
|
|
1009 }
|
|
1010
|
|
1011 // ======= WatcherThread ========
|
|
1012
|
|
1013 // The watcher thread exists to simulate timer interrupts. It should
|
|
1014 // be replaced by an abstraction over whatever native support for
|
|
1015 // timer interrupts exists on the platform.
|
|
1016
|
|
1017 WatcherThread* WatcherThread::_watcher_thread = NULL;
|
|
1018 bool WatcherThread::_should_terminate = false;
|
|
1019
|
|
1020 WatcherThread::WatcherThread() : Thread() {
|
|
1021 assert(watcher_thread() == NULL, "we can only allocate one WatcherThread");
|
|
1022 if (os::create_thread(this, os::watcher_thread)) {
|
|
1023 _watcher_thread = this;
|
|
1024
|
|
1025 // Set the watcher thread to the highest OS priority which should not be
|
|
1026 // used, unless a Java thread with priority java.lang.Thread.MAX_PRIORITY
|
|
1027 // is created. The only normal thread using this priority is the reference
|
|
1028 // handler thread, which runs for very short intervals only.
|
|
1029 // If the VMThread's priority is not lower than the WatcherThread profiling
|
|
1030 // will be inaccurate.
|
|
1031 os::set_priority(this, MaxPriority);
|
|
1032 if (!DisableStartThread) {
|
|
1033 os::start_thread(this);
|
|
1034 }
|
|
1035 }
|
|
1036 }
|
|
1037
|
|
1038 void WatcherThread::run() {
|
|
1039 assert(this == watcher_thread(), "just checking");
|
|
1040
|
|
1041 this->record_stack_base_and_size();
|
|
1042 this->initialize_thread_local_storage();
|
|
1043 this->set_active_handles(JNIHandleBlock::allocate_block());
|
|
1044 while(!_should_terminate) {
|
|
1045 assert(watcher_thread() == Thread::current(), "thread consistency check");
|
|
1046 assert(watcher_thread() == this, "thread consistency check");
|
|
1047
|
|
1048 // Calculate how long it'll be until the next PeriodicTask work
|
|
1049 // should be done, and sleep that amount of time.
|
|
1050 const size_t time_to_wait = PeriodicTask::time_to_wait();
|
|
1051 os::sleep(this, time_to_wait, false);
|
|
1052
|
|
1053 if (is_error_reported()) {
|
|
1054 // A fatal error has happened, the error handler(VMError::report_and_die)
|
|
1055 // should abort JVM after creating an error log file. However in some
|
|
1056 // rare cases, the error handler itself might deadlock. Here we try to
|
|
1057 // kill JVM if the fatal error handler fails to abort in 2 minutes.
|
|
1058 //
|
|
1059 // This code is in WatcherThread because WatcherThread wakes up
|
|
1060 // periodically so the fatal error handler doesn't need to do anything;
|
|
1061 // also because the WatcherThread is less likely to crash than other
|
|
1062 // threads.
|
|
1063
|
|
1064 for (;;) {
|
|
1065 if (!ShowMessageBoxOnError
|
|
1066 && (OnError == NULL || OnError[0] == '\0')
|
|
1067 && Arguments::abort_hook() == NULL) {
|
|
1068 os::sleep(this, 2 * 60 * 1000, false);
|
|
1069 fdStream err(defaultStream::output_fd());
|
|
1070 err.print_raw_cr("# [ timer expired, abort... ]");
|
|
1071 // skip atexit/vm_exit/vm_abort hooks
|
|
1072 os::die();
|
|
1073 }
|
|
1074
|
|
1075 // Wake up 5 seconds later, the fatal handler may reset OnError or
|
|
1076 // ShowMessageBoxOnError when it is ready to abort.
|
|
1077 os::sleep(this, 5 * 1000, false);
|
|
1078 }
|
|
1079 }
|
|
1080
|
|
1081 PeriodicTask::real_time_tick(time_to_wait);
|
|
1082
|
|
1083 // If we have no more tasks left due to dynamic disenrollment,
|
|
1084 // shut down the thread since we don't currently support dynamic enrollment
|
|
1085 if (PeriodicTask::num_tasks() == 0) {
|
|
1086 _should_terminate = true;
|
|
1087 }
|
|
1088 }
|
|
1089
|
|
1090 // Signal that it is terminated
|
|
1091 {
|
|
1092 MutexLockerEx mu(Terminator_lock, Mutex::_no_safepoint_check_flag);
|
|
1093 _watcher_thread = NULL;
|
|
1094 Terminator_lock->notify();
|
|
1095 }
|
|
1096
|
|
1097 // Thread destructor usually does this..
|
|
1098 ThreadLocalStorage::set_thread(NULL);
|
|
1099 }
|
|
1100
|
|
1101 void WatcherThread::start() {
|
|
1102 if (watcher_thread() == NULL) {
|
|
1103 _should_terminate = false;
|
|
1104 // Create the single instance of WatcherThread
|
|
1105 new WatcherThread();
|
|
1106 }
|
|
1107 }
|
|
1108
|
|
1109 void WatcherThread::stop() {
|
|
1110 // it is ok to take late safepoints here, if needed
|
|
1111 MutexLocker mu(Terminator_lock);
|
|
1112 _should_terminate = true;
|
|
1113 while(watcher_thread() != NULL) {
|
|
1114 // This wait should make safepoint checks, wait without a timeout,
|
|
1115 // and wait as a suspend-equivalent condition.
|
|
1116 //
|
|
1117 // Note: If the FlatProfiler is running, then this thread is waiting
|
|
1118 // for the WatcherThread to terminate and the WatcherThread, via the
|
|
1119 // FlatProfiler task, is waiting for the external suspend request on
|
|
1120 // this thread to complete. wait_for_ext_suspend_completion() will
|
|
1121 // eventually timeout, but that takes time. Making this wait a
|
|
1122 // suspend-equivalent condition solves that timeout problem.
|
|
1123 //
|
|
1124 Terminator_lock->wait(!Mutex::_no_safepoint_check_flag, 0,
|
|
1125 Mutex::_as_suspend_equivalent_flag);
|
|
1126 }
|
|
1127 }
|
|
1128
|
|
1129 void WatcherThread::print_on(outputStream* st) const {
|
|
1130 st->print("\"%s\" ", name());
|
|
1131 Thread::print_on(st);
|
|
1132 st->cr();
|
|
1133 }
|
|
1134
|
|
1135 // ======= JavaThread ========
|
|
1136
|
|
1137 // A JavaThread is a normal Java thread
|
|
1138
|
|
1139 void JavaThread::initialize() {
|
|
1140 // Initialize fields
|
|
1141 set_saved_exception_pc(NULL);
|
|
1142 set_threadObj(NULL);
|
|
1143 _anchor.clear();
|
|
1144 set_entry_point(NULL);
|
|
1145 set_jni_functions(jni_functions());
|
|
1146 set_callee_target(NULL);
|
|
1147 set_vm_result(NULL);
|
|
1148 set_vm_result_2(NULL);
|
|
1149 set_vframe_array_head(NULL);
|
|
1150 set_vframe_array_last(NULL);
|
|
1151 set_deferred_locals(NULL);
|
|
1152 set_deopt_mark(NULL);
|
|
1153 clear_must_deopt_id();
|
|
1154 set_monitor_chunks(NULL);
|
|
1155 set_next(NULL);
|
|
1156 set_thread_state(_thread_new);
|
|
1157 _terminated = _not_terminated;
|
|
1158 _privileged_stack_top = NULL;
|
|
1159 _array_for_gc = NULL;
|
|
1160 _suspend_equivalent = false;
|
|
1161 _in_deopt_handler = 0;
|
|
1162 _doing_unsafe_access = false;
|
|
1163 _stack_guard_state = stack_guard_unused;
|
|
1164 _exception_oop = NULL;
|
|
1165 _exception_pc = 0;
|
|
1166 _exception_handler_pc = 0;
|
|
1167 _exception_stack_size = 0;
|
|
1168 _jvmti_thread_state= NULL;
|
|
1169 _jvmti_get_loaded_classes_closure = NULL;
|
|
1170 _interp_only_mode = 0;
|
|
1171 _special_runtime_exit_condition = _no_async_condition;
|
|
1172 _pending_async_exception = NULL;
|
|
1173 _is_compiling = false;
|
|
1174 _thread_stat = NULL;
|
|
1175 _thread_stat = new ThreadStatistics();
|
|
1176 _blocked_on_compilation = false;
|
|
1177 _jni_active_critical = 0;
|
|
1178 _do_not_unlock_if_synchronized = false;
|
|
1179 _cached_monitor_info = NULL;
|
|
1180 _parker = Parker::Allocate(this) ;
|
|
1181
|
|
1182 #ifndef PRODUCT
|
|
1183 _jmp_ring_index = 0;
|
|
1184 for (int ji = 0 ; ji < jump_ring_buffer_size ; ji++ ) {
|
|
1185 record_jump(NULL, NULL, NULL, 0);
|
|
1186 }
|
|
1187 #endif /* PRODUCT */
|
|
1188
|
|
1189 set_thread_profiler(NULL);
|
|
1190 if (FlatProfiler::is_active()) {
|
|
1191 // This is where we would decide to either give each thread it's own profiler
|
|
1192 // or use one global one from FlatProfiler,
|
|
1193 // or up to some count of the number of profiled threads, etc.
|
|
1194 ThreadProfiler* pp = new ThreadProfiler();
|
|
1195 pp->engage();
|
|
1196 set_thread_profiler(pp);
|
|
1197 }
|
|
1198
|
|
1199 // Setup safepoint state info for this thread
|
|
1200 ThreadSafepointState::create(this);
|
|
1201
|
|
1202 debug_only(_java_call_counter = 0);
|
|
1203
|
|
1204 // JVMTI PopFrame support
|
|
1205 _popframe_condition = popframe_inactive;
|
|
1206 _popframe_preserved_args = NULL;
|
|
1207 _popframe_preserved_args_size = 0;
|
|
1208
|
|
1209 pd_initialize();
|
|
1210 }
|
|
1211
|
|
1212 JavaThread::JavaThread(bool is_attaching) : Thread() {
|
|
1213 initialize();
|
|
1214 _is_attaching = is_attaching;
|
|
1215 }
|
|
1216
|
|
1217 bool JavaThread::reguard_stack(address cur_sp) {
|
|
1218 if (_stack_guard_state != stack_guard_yellow_disabled) {
|
|
1219 return true; // Stack already guarded or guard pages not needed.
|
|
1220 }
|
|
1221
|
|
1222 if (register_stack_overflow()) {
|
|
1223 // For those architectures which have separate register and
|
|
1224 // memory stacks, we must check the register stack to see if
|
|
1225 // it has overflowed.
|
|
1226 return false;
|
|
1227 }
|
|
1228
|
|
1229 // Java code never executes within the yellow zone: the latter is only
|
|
1230 // there to provoke an exception during stack banging. If java code
|
|
1231 // is executing there, either StackShadowPages should be larger, or
|
|
1232 // some exception code in c1, c2 or the interpreter isn't unwinding
|
|
1233 // when it should.
|
|
1234 guarantee(cur_sp > stack_yellow_zone_base(), "not enough space to reguard - increase StackShadowPages");
|
|
1235
|
|
1236 enable_stack_yellow_zone();
|
|
1237 return true;
|
|
1238 }
|
|
1239
|
|
1240 bool JavaThread::reguard_stack(void) {
|
|
1241 return reguard_stack(os::current_stack_pointer());
|
|
1242 }
|
|
1243
|
|
1244
|
|
1245 void JavaThread::block_if_vm_exited() {
|
|
1246 if (_terminated == _vm_exited) {
|
|
1247 // _vm_exited is set at safepoint, and Threads_lock is never released
|
|
1248 // we will block here forever
|
|
1249 Threads_lock->lock_without_safepoint_check();
|
|
1250 ShouldNotReachHere();
|
|
1251 }
|
|
1252 }
|
|
1253
|
|
1254
|
|
1255 // Remove this ifdef when C1 is ported to the compiler interface.
|
|
1256 static void compiler_thread_entry(JavaThread* thread, TRAPS);
|
|
1257
|
|
1258 JavaThread::JavaThread(ThreadFunction entry_point, size_t stack_sz) : Thread() {
|
|
1259 if (TraceThreadEvents) {
|
|
1260 tty->print_cr("creating thread %p", this);
|
|
1261 }
|
|
1262 initialize();
|
|
1263 _is_attaching = false;
|
|
1264 set_entry_point(entry_point);
|
|
1265 // Create the native thread itself.
|
|
1266 // %note runtime_23
|
|
1267 os::ThreadType thr_type = os::java_thread;
|
|
1268 thr_type = entry_point == &compiler_thread_entry ? os::compiler_thread :
|
|
1269 os::java_thread;
|
|
1270 os::create_thread(this, thr_type, stack_sz);
|
|
1271
|
|
1272 // The _osthread may be NULL here because we ran out of memory (too many threads active).
|
|
1273 // We need to throw and OutOfMemoryError - however we cannot do this here because the caller
|
|
1274 // may hold a lock and all locks must be unlocked before throwing the exception (throwing
|
|
1275 // the exception consists of creating the exception object & initializing it, initialization
|
|
1276 // will leave the VM via a JavaCall and then all locks must be unlocked).
|
|
1277 //
|
|
1278 // The thread is still suspended when we reach here. Thread must be explicit started
|
|
1279 // by creator! Furthermore, the thread must also explicitly be added to the Threads list
|
|
1280 // by calling Threads:add. The reason why this is not done here, is because the thread
|
|
1281 // object must be fully initialized (take a look at JVM_Start)
|
|
1282 }
|
|
1283
|
|
1284 JavaThread::~JavaThread() {
|
|
1285 if (TraceThreadEvents) {
|
|
1286 tty->print_cr("terminate thread %p", this);
|
|
1287 }
|
|
1288
|
|
1289 // JSR166 -- return the parker to the free list
|
|
1290 Parker::Release(_parker);
|
|
1291 _parker = NULL ;
|
|
1292
|
|
1293 // Free any remaining previous UnrollBlock
|
|
1294 vframeArray* old_array = vframe_array_last();
|
|
1295
|
|
1296 if (old_array != NULL) {
|
|
1297 Deoptimization::UnrollBlock* old_info = old_array->unroll_block();
|
|
1298 old_array->set_unroll_block(NULL);
|
|
1299 delete old_info;
|
|
1300 delete old_array;
|
|
1301 }
|
|
1302
|
|
1303 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred = deferred_locals();
|
|
1304 if (deferred != NULL) {
|
|
1305 // This can only happen if thread is destroyed before deoptimization occurs.
|
|
1306 assert(deferred->length() != 0, "empty array!");
|
|
1307 do {
|
|
1308 jvmtiDeferredLocalVariableSet* dlv = deferred->at(0);
|
|
1309 deferred->remove_at(0);
|
|
1310 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
|
|
1311 delete dlv;
|
|
1312 } while (deferred->length() != 0);
|
|
1313 delete deferred;
|
|
1314 }
|
|
1315
|
|
1316 // All Java related clean up happens in exit
|
|
1317 ThreadSafepointState::destroy(this);
|
|
1318 if (_thread_profiler != NULL) delete _thread_profiler;
|
|
1319 if (_thread_stat != NULL) delete _thread_stat;
|
|
1320
|
|
1321 if (jvmti_thread_state() != NULL) {
|
|
1322 JvmtiExport::cleanup_thread(this);
|
|
1323 }
|
|
1324 }
|
|
1325
|
|
1326
|
|
1327 // The first routine called by a new Java thread
|
|
1328 void JavaThread::run() {
|
|
1329 // initialize thread-local alloc buffer related fields
|
|
1330 this->initialize_tlab();
|
|
1331
|
|
1332 // used to test validitity of stack trace backs
|
|
1333 this->record_base_of_stack_pointer();
|
|
1334
|
|
1335 // Record real stack base and size.
|
|
1336 this->record_stack_base_and_size();
|
|
1337
|
|
1338 // Initialize thread local storage; set before calling MutexLocker
|
|
1339 this->initialize_thread_local_storage();
|
|
1340
|
|
1341 this->create_stack_guard_pages();
|
|
1342
|
|
1343 // Thread is now sufficient initialized to be handled by the safepoint code as being
|
|
1344 // in the VM. Change thread state from _thread_new to _thread_in_vm
|
|
1345 ThreadStateTransition::transition_and_fence(this, _thread_new, _thread_in_vm);
|
|
1346
|
|
1347 assert(JavaThread::current() == this, "sanity check");
|
|
1348 assert(!Thread::current()->owns_locks(), "sanity check");
|
|
1349
|
|
1350 DTRACE_THREAD_PROBE(start, this);
|
|
1351
|
|
1352 // This operation might block. We call that after all safepoint checks for a new thread has
|
|
1353 // been completed.
|
|
1354 this->set_active_handles(JNIHandleBlock::allocate_block());
|
|
1355
|
|
1356 if (JvmtiExport::should_post_thread_life()) {
|
|
1357 JvmtiExport::post_thread_start(this);
|
|
1358 }
|
|
1359
|
|
1360 // We call another function to do the rest so we are sure that the stack addresses used
|
|
1361 // from there will be lower than the stack base just computed
|
|
1362 thread_main_inner();
|
|
1363
|
|
1364 // Note, thread is no longer valid at this point!
|
|
1365 }
|
|
1366
|
|
1367
|
|
1368 void JavaThread::thread_main_inner() {
|
|
1369 assert(JavaThread::current() == this, "sanity check");
|
|
1370 assert(this->threadObj() != NULL, "just checking");
|
|
1371
|
|
1372 // Execute thread entry point. If this thread is being asked to restart,
|
|
1373 // or has been stopped before starting, do not reexecute entry point.
|
|
1374 // Note: Due to JVM_StopThread we can have pending exceptions already!
|
|
1375 if (!this->has_pending_exception() && !java_lang_Thread::is_stillborn(this->threadObj())) {
|
|
1376 // enter the thread's entry point only if we have no pending exceptions
|
|
1377 HandleMark hm(this);
|
|
1378 this->entry_point()(this, this);
|
|
1379 }
|
|
1380
|
|
1381 DTRACE_THREAD_PROBE(stop, this);
|
|
1382
|
|
1383 this->exit(false);
|
|
1384 delete this;
|
|
1385 }
|
|
1386
|
|
1387
|
|
1388 static void ensure_join(JavaThread* thread) {
|
|
1389 // We do not need to grap the Threads_lock, since we are operating on ourself.
|
|
1390 Handle threadObj(thread, thread->threadObj());
|
|
1391 assert(threadObj.not_null(), "java thread object must exist");
|
|
1392 ObjectLocker lock(threadObj, thread);
|
|
1393 // Ignore pending exception (ThreadDeath), since we are exiting anyway
|
|
1394 thread->clear_pending_exception();
|
|
1395 // It is of profound importance that we set the stillborn bit and reset the thread object,
|
|
1396 // before we do the notify. Since, changing these two variable will make JVM_IsAlive return
|
|
1397 // false. So in case another thread is doing a join on this thread , it will detect that the thread
|
|
1398 // is dead when it gets notified.
|
|
1399 java_lang_Thread::set_stillborn(threadObj());
|
|
1400 // Thread is exiting. So set thread_status field in java.lang.Thread class to TERMINATED.
|
|
1401 java_lang_Thread::set_thread_status(threadObj(), java_lang_Thread::TERMINATED);
|
|
1402 java_lang_Thread::set_thread(threadObj(), NULL);
|
|
1403 lock.notify_all(thread);
|
|
1404 // Ignore pending exception (ThreadDeath), since we are exiting anyway
|
|
1405 thread->clear_pending_exception();
|
|
1406 }
|
|
1407
|
|
1408 // For any new cleanup additions, please check to see if they need to be applied to
|
|
1409 // cleanup_failed_attach_current_thread as well.
|
|
1410 void JavaThread::exit(bool destroy_vm, ExitType exit_type) {
|
|
1411 assert(this == JavaThread::current(), "thread consistency check");
|
|
1412 if (!InitializeJavaLangSystem) return;
|
|
1413
|
|
1414 HandleMark hm(this);
|
|
1415 Handle uncaught_exception(this, this->pending_exception());
|
|
1416 this->clear_pending_exception();
|
|
1417 Handle threadObj(this, this->threadObj());
|
|
1418 assert(threadObj.not_null(), "Java thread object should be created");
|
|
1419
|
|
1420 if (get_thread_profiler() != NULL) {
|
|
1421 get_thread_profiler()->disengage();
|
|
1422 ResourceMark rm;
|
|
1423 get_thread_profiler()->print(get_thread_name());
|
|
1424 }
|
|
1425
|
|
1426
|
|
1427 // FIXIT: This code should be moved into else part, when reliable 1.2/1.3 check is in place
|
|
1428 {
|
|
1429 EXCEPTION_MARK;
|
|
1430
|
|
1431 CLEAR_PENDING_EXCEPTION;
|
|
1432 }
|
|
1433 // FIXIT: The is_null check is only so it works better on JDK1.2 VM's. This
|
|
1434 // has to be fixed by a runtime query method
|
|
1435 if (!destroy_vm || JDK_Version::is_jdk12x_version()) {
|
|
1436 // JSR-166: change call from from ThreadGroup.uncaughtException to
|
|
1437 // java.lang.Thread.dispatchUncaughtException
|
|
1438 if (uncaught_exception.not_null()) {
|
|
1439 Handle group(this, java_lang_Thread::threadGroup(threadObj()));
|
|
1440 Events::log("uncaught exception INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT",
|
|
1441 (address)uncaught_exception(), (address)threadObj(), (address)group());
|
|
1442 {
|
|
1443 EXCEPTION_MARK;
|
|
1444 // Check if the method Thread.dispatchUncaughtException() exists. If so
|
|
1445 // call it. Otherwise we have an older library without the JSR-166 changes,
|
|
1446 // so call ThreadGroup.uncaughtException()
|
|
1447 KlassHandle recvrKlass(THREAD, threadObj->klass());
|
|
1448 CallInfo callinfo;
|
|
1449 KlassHandle thread_klass(THREAD, SystemDictionary::thread_klass());
|
|
1450 LinkResolver::resolve_virtual_call(callinfo, threadObj, recvrKlass, thread_klass,
|
|
1451 vmSymbolHandles::dispatchUncaughtException_name(),
|
|
1452 vmSymbolHandles::throwable_void_signature(),
|
|
1453 KlassHandle(), false, false, THREAD);
|
|
1454 CLEAR_PENDING_EXCEPTION;
|
|
1455 methodHandle method = callinfo.selected_method();
|
|
1456 if (method.not_null()) {
|
|
1457 JavaValue result(T_VOID);
|
|
1458 JavaCalls::call_virtual(&result,
|
|
1459 threadObj, thread_klass,
|
|
1460 vmSymbolHandles::dispatchUncaughtException_name(),
|
|
1461 vmSymbolHandles::throwable_void_signature(),
|
|
1462 uncaught_exception,
|
|
1463 THREAD);
|
|
1464 } else {
|
|
1465 KlassHandle thread_group(THREAD, SystemDictionary::threadGroup_klass());
|
|
1466 JavaValue result(T_VOID);
|
|
1467 JavaCalls::call_virtual(&result,
|
|
1468 group, thread_group,
|
|
1469 vmSymbolHandles::uncaughtException_name(),
|
|
1470 vmSymbolHandles::thread_throwable_void_signature(),
|
|
1471 threadObj, // Arg 1
|
|
1472 uncaught_exception, // Arg 2
|
|
1473 THREAD);
|
|
1474 }
|
|
1475 CLEAR_PENDING_EXCEPTION;
|
|
1476 }
|
|
1477 }
|
|
1478
|
|
1479 // Call Thread.exit(). We try 3 times in case we got another Thread.stop during
|
|
1480 // the execution of the method. If that is not enough, then we don't really care. Thread.stop
|
|
1481 // is deprecated anyhow.
|
|
1482 { int count = 3;
|
|
1483 while (java_lang_Thread::threadGroup(threadObj()) != NULL && (count-- > 0)) {
|
|
1484 EXCEPTION_MARK;
|
|
1485 JavaValue result(T_VOID);
|
|
1486 KlassHandle thread_klass(THREAD, SystemDictionary::thread_klass());
|
|
1487 JavaCalls::call_virtual(&result,
|
|
1488 threadObj, thread_klass,
|
|
1489 vmSymbolHandles::exit_method_name(),
|
|
1490 vmSymbolHandles::void_method_signature(),
|
|
1491 THREAD);
|
|
1492 CLEAR_PENDING_EXCEPTION;
|
|
1493 }
|
|
1494 }
|
|
1495
|
|
1496 // notify JVMTI
|
|
1497 if (JvmtiExport::should_post_thread_life()) {
|
|
1498 JvmtiExport::post_thread_end(this);
|
|
1499 }
|
|
1500
|
|
1501 // We have notified the agents that we are exiting, before we go on,
|
|
1502 // we must check for a pending external suspend request and honor it
|
|
1503 // in order to not surprise the thread that made the suspend request.
|
|
1504 while (true) {
|
|
1505 {
|
|
1506 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
1507 if (!is_external_suspend()) {
|
|
1508 set_terminated(_thread_exiting);
|
|
1509 ThreadService::current_thread_exiting(this);
|
|
1510 break;
|
|
1511 }
|
|
1512 // Implied else:
|
|
1513 // Things get a little tricky here. We have a pending external
|
|
1514 // suspend request, but we are holding the SR_lock so we
|
|
1515 // can't just self-suspend. So we temporarily drop the lock
|
|
1516 // and then self-suspend.
|
|
1517 }
|
|
1518
|
|
1519 ThreadBlockInVM tbivm(this);
|
|
1520 java_suspend_self();
|
|
1521
|
|
1522 // We're done with this suspend request, but we have to loop around
|
|
1523 // and check again. Eventually we will get SR_lock without a pending
|
|
1524 // external suspend request and will be able to mark ourselves as
|
|
1525 // exiting.
|
|
1526 }
|
|
1527 // no more external suspends are allowed at this point
|
|
1528 } else {
|
|
1529 // before_exit() has already posted JVMTI THREAD_END events
|
|
1530 }
|
|
1531
|
|
1532 // Notify waiters on thread object. This has to be done after exit() is called
|
|
1533 // on the thread (if the thread is the last thread in a daemon ThreadGroup the
|
|
1534 // group should have the destroyed bit set before waiters are notified).
|
|
1535 ensure_join(this);
|
|
1536 assert(!this->has_pending_exception(), "ensure_join should have cleared");
|
|
1537
|
|
1538 // 6282335 JNI DetachCurrentThread spec states that all Java monitors
|
|
1539 // held by this thread must be released. A detach operation must only
|
|
1540 // get here if there are no Java frames on the stack. Therefore, any
|
|
1541 // owned monitors at this point MUST be JNI-acquired monitors which are
|
|
1542 // pre-inflated and in the monitor cache.
|
|
1543 //
|
|
1544 // ensure_join() ignores IllegalThreadStateExceptions, and so does this.
|
|
1545 if (exit_type == jni_detach && JNIDetachReleasesMonitors) {
|
|
1546 assert(!this->has_last_Java_frame(), "detaching with Java frames?");
|
|
1547 ObjectSynchronizer::release_monitors_owned_by_thread(this);
|
|
1548 assert(!this->has_pending_exception(), "release_monitors should have cleared");
|
|
1549 }
|
|
1550
|
|
1551 // These things needs to be done while we are still a Java Thread. Make sure that thread
|
|
1552 // is in a consistent state, in case GC happens
|
|
1553 assert(_privileged_stack_top == NULL, "must be NULL when we get here");
|
|
1554
|
|
1555 if (active_handles() != NULL) {
|
|
1556 JNIHandleBlock* block = active_handles();
|
|
1557 set_active_handles(NULL);
|
|
1558 JNIHandleBlock::release_block(block);
|
|
1559 }
|
|
1560
|
|
1561 if (free_handle_block() != NULL) {
|
|
1562 JNIHandleBlock* block = free_handle_block();
|
|
1563 set_free_handle_block(NULL);
|
|
1564 JNIHandleBlock::release_block(block);
|
|
1565 }
|
|
1566
|
|
1567 // These have to be removed while this is still a valid thread.
|
|
1568 remove_stack_guard_pages();
|
|
1569
|
|
1570 if (UseTLAB) {
|
|
1571 tlab().make_parsable(true); // retire TLAB
|
|
1572 }
|
|
1573
|
|
1574 // Remove from list of active threads list, and notify VM thread if we are the last non-daemon thread
|
|
1575 Threads::remove(this);
|
|
1576 }
|
|
1577
|
|
1578 void JavaThread::cleanup_failed_attach_current_thread() {
|
|
1579
|
|
1580 if (get_thread_profiler() != NULL) {
|
|
1581 get_thread_profiler()->disengage();
|
|
1582 ResourceMark rm;
|
|
1583 get_thread_profiler()->print(get_thread_name());
|
|
1584 }
|
|
1585
|
|
1586 if (active_handles() != NULL) {
|
|
1587 JNIHandleBlock* block = active_handles();
|
|
1588 set_active_handles(NULL);
|
|
1589 JNIHandleBlock::release_block(block);
|
|
1590 }
|
|
1591
|
|
1592 if (free_handle_block() != NULL) {
|
|
1593 JNIHandleBlock* block = free_handle_block();
|
|
1594 set_free_handle_block(NULL);
|
|
1595 JNIHandleBlock::release_block(block);
|
|
1596 }
|
|
1597
|
|
1598 if (UseTLAB) {
|
|
1599 tlab().make_parsable(true); // retire TLAB, if any
|
|
1600 }
|
|
1601
|
|
1602 Threads::remove(this);
|
|
1603 delete this;
|
|
1604 }
|
|
1605
|
|
1606
|
|
1607 JavaThread* JavaThread::active() {
|
|
1608 Thread* thread = ThreadLocalStorage::thread();
|
|
1609 assert(thread != NULL, "just checking");
|
|
1610 if (thread->is_Java_thread()) {
|
|
1611 return (JavaThread*) thread;
|
|
1612 } else {
|
|
1613 assert(thread->is_VM_thread(), "this must be a vm thread");
|
|
1614 VM_Operation* op = ((VMThread*) thread)->vm_operation();
|
|
1615 JavaThread *ret=op == NULL ? NULL : (JavaThread *)op->calling_thread();
|
|
1616 assert(ret->is_Java_thread(), "must be a Java thread");
|
|
1617 return ret;
|
|
1618 }
|
|
1619 }
|
|
1620
|
|
1621 bool JavaThread::is_lock_owned(address adr) const {
|
|
1622 if (lock_is_in_stack(adr)) return true;
|
|
1623
|
|
1624 for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) {
|
|
1625 if (chunk->contains(adr)) return true;
|
|
1626 }
|
|
1627
|
|
1628 return false;
|
|
1629 }
|
|
1630
|
|
1631
|
|
1632 void JavaThread::add_monitor_chunk(MonitorChunk* chunk) {
|
|
1633 chunk->set_next(monitor_chunks());
|
|
1634 set_monitor_chunks(chunk);
|
|
1635 }
|
|
1636
|
|
1637 void JavaThread::remove_monitor_chunk(MonitorChunk* chunk) {
|
|
1638 guarantee(monitor_chunks() != NULL, "must be non empty");
|
|
1639 if (monitor_chunks() == chunk) {
|
|
1640 set_monitor_chunks(chunk->next());
|
|
1641 } else {
|
|
1642 MonitorChunk* prev = monitor_chunks();
|
|
1643 while (prev->next() != chunk) prev = prev->next();
|
|
1644 prev->set_next(chunk->next());
|
|
1645 }
|
|
1646 }
|
|
1647
|
|
1648 // JVM support.
|
|
1649
|
|
1650 // Note: this function shouldn't block if it's called in
|
|
1651 // _thread_in_native_trans state (such as from
|
|
1652 // check_special_condition_for_native_trans()).
|
|
1653 void JavaThread::check_and_handle_async_exceptions(bool check_unsafe_error) {
|
|
1654
|
|
1655 if (has_last_Java_frame() && has_async_condition()) {
|
|
1656 // If we are at a polling page safepoint (not a poll return)
|
|
1657 // then we must defer async exception because live registers
|
|
1658 // will be clobbered by the exception path. Poll return is
|
|
1659 // ok because the call we a returning from already collides
|
|
1660 // with exception handling registers and so there is no issue.
|
|
1661 // (The exception handling path kills call result registers but
|
|
1662 // this is ok since the exception kills the result anyway).
|
|
1663
|
|
1664 if (is_at_poll_safepoint()) {
|
|
1665 // if the code we are returning to has deoptimized we must defer
|
|
1666 // the exception otherwise live registers get clobbered on the
|
|
1667 // exception path before deoptimization is able to retrieve them.
|
|
1668 //
|
|
1669 RegisterMap map(this, false);
|
|
1670 frame caller_fr = last_frame().sender(&map);
|
|
1671 assert(caller_fr.is_compiled_frame(), "what?");
|
|
1672 if (caller_fr.is_deoptimized_frame()) {
|
|
1673 if (TraceExceptions) {
|
|
1674 ResourceMark rm;
|
|
1675 tty->print_cr("deferred async exception at compiled safepoint");
|
|
1676 }
|
|
1677 return;
|
|
1678 }
|
|
1679 }
|
|
1680 }
|
|
1681
|
|
1682 JavaThread::AsyncRequests condition = clear_special_runtime_exit_condition();
|
|
1683 if (condition == _no_async_condition) {
|
|
1684 // Conditions have changed since has_special_runtime_exit_condition()
|
|
1685 // was called:
|
|
1686 // - if we were here only because of an external suspend request,
|
|
1687 // then that was taken care of above (or cancelled) so we are done
|
|
1688 // - if we were here because of another async request, then it has
|
|
1689 // been cleared between the has_special_runtime_exit_condition()
|
|
1690 // and now so again we are done
|
|
1691 return;
|
|
1692 }
|
|
1693
|
|
1694 // Check for pending async. exception
|
|
1695 if (_pending_async_exception != NULL) {
|
|
1696 // Only overwrite an already pending exception, if it is not a threadDeath.
|
|
1697 if (!has_pending_exception() || !pending_exception()->is_a(SystemDictionary::threaddeath_klass())) {
|
|
1698
|
|
1699 // We cannot call Exceptions::_throw(...) here because we cannot block
|
|
1700 set_pending_exception(_pending_async_exception, __FILE__, __LINE__);
|
|
1701
|
|
1702 if (TraceExceptions) {
|
|
1703 ResourceMark rm;
|
|
1704 tty->print("Async. exception installed at runtime exit (" INTPTR_FORMAT ")", this);
|
|
1705 if (has_last_Java_frame() ) {
|
|
1706 frame f = last_frame();
|
|
1707 tty->print(" (pc: " INTPTR_FORMAT " sp: " INTPTR_FORMAT " )", f.pc(), f.sp());
|
|
1708 }
|
|
1709 tty->print_cr(" of type: %s", instanceKlass::cast(_pending_async_exception->klass())->external_name());
|
|
1710 }
|
|
1711 _pending_async_exception = NULL;
|
|
1712 clear_has_async_exception();
|
|
1713 }
|
|
1714 }
|
|
1715
|
|
1716 if (check_unsafe_error &&
|
|
1717 condition == _async_unsafe_access_error && !has_pending_exception()) {
|
|
1718 condition = _no_async_condition; // done
|
|
1719 switch (thread_state()) {
|
|
1720 case _thread_in_vm:
|
|
1721 {
|
|
1722 JavaThread* THREAD = this;
|
|
1723 THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in an unsafe memory access operation");
|
|
1724 }
|
|
1725 case _thread_in_native:
|
|
1726 {
|
|
1727 ThreadInVMfromNative tiv(this);
|
|
1728 JavaThread* THREAD = this;
|
|
1729 THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in an unsafe memory access operation");
|
|
1730 }
|
|
1731 case _thread_in_Java:
|
|
1732 {
|
|
1733 ThreadInVMfromJava tiv(this);
|
|
1734 JavaThread* THREAD = this;
|
|
1735 THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in a recent unsafe memory access operation in compiled Java code");
|
|
1736 }
|
|
1737 default:
|
|
1738 ShouldNotReachHere();
|
|
1739 }
|
|
1740 }
|
|
1741
|
|
1742 assert(condition == _no_async_condition || has_pending_exception() ||
|
|
1743 (!check_unsafe_error && condition == _async_unsafe_access_error),
|
|
1744 "must have handled the async condition, if no exception");
|
|
1745 }
|
|
1746
|
|
1747 void JavaThread::handle_special_runtime_exit_condition(bool check_asyncs) {
|
|
1748 //
|
|
1749 // Check for pending external suspend. Internal suspend requests do
|
|
1750 // not use handle_special_runtime_exit_condition().
|
|
1751 // If JNIEnv proxies are allowed, don't self-suspend if the target
|
|
1752 // thread is not the current thread. In older versions of jdbx, jdbx
|
|
1753 // threads could call into the VM with another thread's JNIEnv so we
|
|
1754 // can be here operating on behalf of a suspended thread (4432884).
|
|
1755 bool do_self_suspend = is_external_suspend_with_lock();
|
|
1756 if (do_self_suspend && (!AllowJNIEnvProxy || this == JavaThread::current())) {
|
|
1757 //
|
|
1758 // Because thread is external suspended the safepoint code will count
|
|
1759 // thread as at a safepoint. This can be odd because we can be here
|
|
1760 // as _thread_in_Java which would normally transition to _thread_blocked
|
|
1761 // at a safepoint. We would like to mark the thread as _thread_blocked
|
|
1762 // before calling java_suspend_self like all other callers of it but
|
|
1763 // we must then observe proper safepoint protocol. (We can't leave
|
|
1764 // _thread_blocked with a safepoint in progress). However we can be
|
|
1765 // here as _thread_in_native_trans so we can't use a normal transition
|
|
1766 // constructor/destructor pair because they assert on that type of
|
|
1767 // transition. We could do something like:
|
|
1768 //
|
|
1769 // JavaThreadState state = thread_state();
|
|
1770 // set_thread_state(_thread_in_vm);
|
|
1771 // {
|
|
1772 // ThreadBlockInVM tbivm(this);
|
|
1773 // java_suspend_self()
|
|
1774 // }
|
|
1775 // set_thread_state(_thread_in_vm_trans);
|
|
1776 // if (safepoint) block;
|
|
1777 // set_thread_state(state);
|
|
1778 //
|
|
1779 // but that is pretty messy. Instead we just go with the way the
|
|
1780 // code has worked before and note that this is the only path to
|
|
1781 // java_suspend_self that doesn't put the thread in _thread_blocked
|
|
1782 // mode.
|
|
1783
|
|
1784 frame_anchor()->make_walkable(this);
|
|
1785 java_suspend_self();
|
|
1786
|
|
1787 // We might be here for reasons in addition to the self-suspend request
|
|
1788 // so check for other async requests.
|
|
1789 }
|
|
1790
|
|
1791 if (check_asyncs) {
|
|
1792 check_and_handle_async_exceptions();
|
|
1793 }
|
|
1794 }
|
|
1795
|
|
1796 void JavaThread::send_thread_stop(oop java_throwable) {
|
|
1797 assert(Thread::current()->is_VM_thread(), "should be in the vm thread");
|
|
1798 assert(Threads_lock->is_locked(), "Threads_lock should be locked by safepoint code");
|
|
1799 assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
|
|
1800
|
|
1801 // Do not throw asynchronous exceptions against the compiler thread
|
|
1802 // (the compiler thread should not be a Java thread -- fix in 1.4.2)
|
|
1803 if (is_Compiler_thread()) return;
|
|
1804
|
|
1805 // This is a change from JDK 1.1, but JDK 1.2 will also do it:
|
|
1806 if (java_throwable->is_a(SystemDictionary::threaddeath_klass())) {
|
|
1807 java_lang_Thread::set_stillborn(threadObj());
|
|
1808 }
|
|
1809
|
|
1810 {
|
|
1811 // Actually throw the Throwable against the target Thread - however
|
|
1812 // only if there is no thread death exception installed already.
|
|
1813 if (_pending_async_exception == NULL || !_pending_async_exception->is_a(SystemDictionary::threaddeath_klass())) {
|
|
1814 // If the topmost frame is a runtime stub, then we are calling into
|
|
1815 // OptoRuntime from compiled code. Some runtime stubs (new, monitor_exit..)
|
|
1816 // must deoptimize the caller before continuing, as the compiled exception handler table
|
|
1817 // may not be valid
|
|
1818 if (has_last_Java_frame()) {
|
|
1819 frame f = last_frame();
|
|
1820 if (f.is_runtime_frame() || f.is_safepoint_blob_frame()) {
|
|
1821 // BiasedLocking needs an updated RegisterMap for the revoke monitors pass
|
|
1822 RegisterMap reg_map(this, UseBiasedLocking);
|
|
1823 frame compiled_frame = f.sender(®_map);
|
|
1824 if (compiled_frame.can_be_deoptimized()) {
|
|
1825 Deoptimization::deoptimize(this, compiled_frame, ®_map);
|
|
1826 }
|
|
1827 }
|
|
1828 }
|
|
1829
|
|
1830 // Set async. pending exception in thread.
|
|
1831 set_pending_async_exception(java_throwable);
|
|
1832
|
|
1833 if (TraceExceptions) {
|
|
1834 ResourceMark rm;
|
|
1835 tty->print_cr("Pending Async. exception installed of type: %s", instanceKlass::cast(_pending_async_exception->klass())->external_name());
|
|
1836 }
|
|
1837 // for AbortVMOnException flag
|
|
1838 NOT_PRODUCT(Exceptions::debug_check_abort(instanceKlass::cast(_pending_async_exception->klass())->external_name()));
|
|
1839 }
|
|
1840 }
|
|
1841
|
|
1842
|
|
1843 // Interrupt thread so it will wake up from a potential wait()
|
|
1844 Thread::interrupt(this);
|
|
1845 }
|
|
1846
|
|
1847 // External suspension mechanism.
|
|
1848 //
|
|
1849 // Tell the VM to suspend a thread when ever it knows that it does not hold on
|
|
1850 // to any VM_locks and it is at a transition
|
|
1851 // Self-suspension will happen on the transition out of the vm.
|
|
1852 // Catch "this" coming in from JNIEnv pointers when the thread has been freed
|
|
1853 //
|
|
1854 // Guarantees on return:
|
|
1855 // + Target thread will not execute any new bytecode (that's why we need to
|
|
1856 // force a safepoint)
|
|
1857 // + Target thread will not enter any new monitors
|
|
1858 //
|
|
1859 void JavaThread::java_suspend() {
|
|
1860 { MutexLocker mu(Threads_lock);
|
|
1861 if (!Threads::includes(this) || is_exiting() || this->threadObj() == NULL) {
|
|
1862 return;
|
|
1863 }
|
|
1864 }
|
|
1865
|
|
1866 { MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
1867 if (!is_external_suspend()) {
|
|
1868 // a racing resume has cancelled us; bail out now
|
|
1869 return;
|
|
1870 }
|
|
1871
|
|
1872 // suspend is done
|
|
1873 uint32_t debug_bits = 0;
|
|
1874 // Warning: is_ext_suspend_completed() may temporarily drop the
|
|
1875 // SR_lock to allow the thread to reach a stable thread state if
|
|
1876 // it is currently in a transient thread state.
|
|
1877 if (is_ext_suspend_completed(false /* !called_by_wait */,
|
|
1878 SuspendRetryDelay, &debug_bits) ) {
|
|
1879 return;
|
|
1880 }
|
|
1881 }
|
|
1882
|
|
1883 VM_ForceSafepoint vm_suspend;
|
|
1884 VMThread::execute(&vm_suspend);
|
|
1885 }
|
|
1886
|
|
1887 // Part II of external suspension.
|
|
1888 // A JavaThread self suspends when it detects a pending external suspend
|
|
1889 // request. This is usually on transitions. It is also done in places
|
|
1890 // where continuing to the next transition would surprise the caller,
|
|
1891 // e.g., monitor entry.
|
|
1892 //
|
|
1893 // Returns the number of times that the thread self-suspended.
|
|
1894 //
|
|
1895 // Note: DO NOT call java_suspend_self() when you just want to block current
|
|
1896 // thread. java_suspend_self() is the second stage of cooperative
|
|
1897 // suspension for external suspend requests and should only be used
|
|
1898 // to complete an external suspend request.
|
|
1899 //
|
|
1900 int JavaThread::java_suspend_self() {
|
|
1901 int ret = 0;
|
|
1902
|
|
1903 // we are in the process of exiting so don't suspend
|
|
1904 if (is_exiting()) {
|
|
1905 clear_external_suspend();
|
|
1906 return ret;
|
|
1907 }
|
|
1908
|
|
1909 assert(_anchor.walkable() ||
|
|
1910 (is_Java_thread() && !((JavaThread*)this)->has_last_Java_frame()),
|
|
1911 "must have walkable stack");
|
|
1912
|
|
1913 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
1914
|
|
1915 assert(!this->is_any_suspended(),
|
|
1916 "a thread trying to self-suspend should not already be suspended");
|
|
1917
|
|
1918 if (this->is_suspend_equivalent()) {
|
|
1919 // If we are self-suspending as a result of the lifting of a
|
|
1920 // suspend equivalent condition, then the suspend_equivalent
|
|
1921 // flag is not cleared until we set the ext_suspended flag so
|
|
1922 // that wait_for_ext_suspend_completion() returns consistent
|
|
1923 // results.
|
|
1924 this->clear_suspend_equivalent();
|
|
1925 }
|
|
1926
|
|
1927 // A racing resume may have cancelled us before we grabbed SR_lock
|
|
1928 // above. Or another external suspend request could be waiting for us
|
|
1929 // by the time we return from SR_lock()->wait(). The thread
|
|
1930 // that requested the suspension may already be trying to walk our
|
|
1931 // stack and if we return now, we can change the stack out from under
|
|
1932 // it. This would be a "bad thing (TM)" and cause the stack walker
|
|
1933 // to crash. We stay self-suspended until there are no more pending
|
|
1934 // external suspend requests.
|
|
1935 while (is_external_suspend()) {
|
|
1936 ret++;
|
|
1937 this->set_ext_suspended();
|
|
1938
|
|
1939 // _ext_suspended flag is cleared by java_resume()
|
|
1940 while (is_ext_suspended()) {
|
|
1941 this->SR_lock()->wait(Mutex::_no_safepoint_check_flag);
|
|
1942 }
|
|
1943 }
|
|
1944
|
|
1945 return ret;
|
|
1946 }
|
|
1947
|
|
1948 #ifdef ASSERT
|
|
1949 // verify the JavaThread has not yet been published in the Threads::list, and
|
|
1950 // hence doesn't need protection from concurrent access at this stage
|
|
1951 void JavaThread::verify_not_published() {
|
|
1952 if (!Threads_lock->owned_by_self()) {
|
|
1953 MutexLockerEx ml(Threads_lock, Mutex::_no_safepoint_check_flag);
|
|
1954 assert( !Threads::includes(this),
|
|
1955 "java thread shouldn't have been published yet!");
|
|
1956 }
|
|
1957 else {
|
|
1958 assert( !Threads::includes(this),
|
|
1959 "java thread shouldn't have been published yet!");
|
|
1960 }
|
|
1961 }
|
|
1962 #endif
|
|
1963
|
|
1964 // Slow path when the native==>VM/Java barriers detect a safepoint is in
|
|
1965 // progress or when _suspend_flags is non-zero.
|
|
1966 // Current thread needs to self-suspend if there is a suspend request and/or
|
|
1967 // block if a safepoint is in progress.
|
|
1968 // Async exception ISN'T checked.
|
|
1969 // Note only the ThreadInVMfromNative transition can call this function
|
|
1970 // directly and when thread state is _thread_in_native_trans
|
|
1971 void JavaThread::check_safepoint_and_suspend_for_native_trans(JavaThread *thread) {
|
|
1972 assert(thread->thread_state() == _thread_in_native_trans, "wrong state");
|
|
1973
|
|
1974 JavaThread *curJT = JavaThread::current();
|
|
1975 bool do_self_suspend = thread->is_external_suspend();
|
|
1976
|
|
1977 assert(!curJT->has_last_Java_frame() || curJT->frame_anchor()->walkable(), "Unwalkable stack in native->vm transition");
|
|
1978
|
|
1979 // If JNIEnv proxies are allowed, don't self-suspend if the target
|
|
1980 // thread is not the current thread. In older versions of jdbx, jdbx
|
|
1981 // threads could call into the VM with another thread's JNIEnv so we
|
|
1982 // can be here operating on behalf of a suspended thread (4432884).
|
|
1983 if (do_self_suspend && (!AllowJNIEnvProxy || curJT == thread)) {
|
|
1984 JavaThreadState state = thread->thread_state();
|
|
1985
|
|
1986 // We mark this thread_blocked state as a suspend-equivalent so
|
|
1987 // that a caller to is_ext_suspend_completed() won't be confused.
|
|
1988 // The suspend-equivalent state is cleared by java_suspend_self().
|
|
1989 thread->set_suspend_equivalent();
|
|
1990
|
|
1991 // If the safepoint code sees the _thread_in_native_trans state, it will
|
|
1992 // wait until the thread changes to other thread state. There is no
|
|
1993 // guarantee on how soon we can obtain the SR_lock and complete the
|
|
1994 // self-suspend request. It would be a bad idea to let safepoint wait for
|
|
1995 // too long. Temporarily change the state to _thread_blocked to
|
|
1996 // let the VM thread know that this thread is ready for GC. The problem
|
|
1997 // of changing thread state is that safepoint could happen just after
|
|
1998 // java_suspend_self() returns after being resumed, and VM thread will
|
|
1999 // see the _thread_blocked state. We must check for safepoint
|
|
2000 // after restoring the state and make sure we won't leave while a safepoint
|
|
2001 // is in progress.
|
|
2002 thread->set_thread_state(_thread_blocked);
|
|
2003 thread->java_suspend_self();
|
|
2004 thread->set_thread_state(state);
|
|
2005 // Make sure new state is seen by VM thread
|
|
2006 if (os::is_MP()) {
|
|
2007 if (UseMembar) {
|
|
2008 // Force a fence between the write above and read below
|
|
2009 OrderAccess::fence();
|
|
2010 } else {
|
|
2011 // Must use this rather than serialization page in particular on Windows
|
|
2012 InterfaceSupport::serialize_memory(thread);
|
|
2013 }
|
|
2014 }
|
|
2015 }
|
|
2016
|
|
2017 if (SafepointSynchronize::do_call_back()) {
|
|
2018 // If we are safepointing, then block the caller which may not be
|
|
2019 // the same as the target thread (see above).
|
|
2020 SafepointSynchronize::block(curJT);
|
|
2021 }
|
|
2022
|
|
2023 if (thread->is_deopt_suspend()) {
|
|
2024 thread->clear_deopt_suspend();
|
|
2025 RegisterMap map(thread, false);
|
|
2026 frame f = thread->last_frame();
|
|
2027 while ( f.id() != thread->must_deopt_id() && ! f.is_first_frame()) {
|
|
2028 f = f.sender(&map);
|
|
2029 }
|
|
2030 if (f.id() == thread->must_deopt_id()) {
|
|
2031 thread->clear_must_deopt_id();
|
|
2032 // Since we know we're safe to deopt the current state is a safe state
|
|
2033 f.deoptimize(thread, true);
|
|
2034 } else {
|
|
2035 fatal("missed deoptimization!");
|
|
2036 }
|
|
2037 }
|
|
2038 }
|
|
2039
|
|
2040 // Slow path when the native==>VM/Java barriers detect a safepoint is in
|
|
2041 // progress or when _suspend_flags is non-zero.
|
|
2042 // Current thread needs to self-suspend if there is a suspend request and/or
|
|
2043 // block if a safepoint is in progress.
|
|
2044 // Also check for pending async exception (not including unsafe access error).
|
|
2045 // Note only the native==>VM/Java barriers can call this function and when
|
|
2046 // thread state is _thread_in_native_trans.
|
|
2047 void JavaThread::check_special_condition_for_native_trans(JavaThread *thread) {
|
|
2048 check_safepoint_and_suspend_for_native_trans(thread);
|
|
2049
|
|
2050 if (thread->has_async_exception()) {
|
|
2051 // We are in _thread_in_native_trans state, don't handle unsafe
|
|
2052 // access error since that may block.
|
|
2053 thread->check_and_handle_async_exceptions(false);
|
|
2054 }
|
|
2055 }
|
|
2056
|
|
2057 // We need to guarantee the Threads_lock here, since resumes are not
|
|
2058 // allowed during safepoint synchronization
|
|
2059 // Can only resume from an external suspension
|
|
2060 void JavaThread::java_resume() {
|
|
2061 assert_locked_or_safepoint(Threads_lock);
|
|
2062
|
|
2063 // Sanity check: thread is gone, has started exiting or the thread
|
|
2064 // was not externally suspended.
|
|
2065 if (!Threads::includes(this) || is_exiting() || !is_external_suspend()) {
|
|
2066 return;
|
|
2067 }
|
|
2068
|
|
2069 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
|
|
2070
|
|
2071 clear_external_suspend();
|
|
2072
|
|
2073 if (is_ext_suspended()) {
|
|
2074 clear_ext_suspended();
|
|
2075 SR_lock()->notify_all();
|
|
2076 }
|
|
2077 }
|
|
2078
|
|
2079 void JavaThread::create_stack_guard_pages() {
|
|
2080 if (! os::uses_stack_guard_pages() || _stack_guard_state != stack_guard_unused) return;
|
|
2081 address low_addr = stack_base() - stack_size();
|
|
2082 size_t len = (StackYellowPages + StackRedPages) * os::vm_page_size();
|
|
2083
|
|
2084 int allocate = os::allocate_stack_guard_pages();
|
|
2085 // warning("Guarding at " PTR_FORMAT " for len " SIZE_FORMAT "\n", low_addr, len);
|
|
2086
|
|
2087 if (allocate && !os::commit_memory((char *) low_addr, len)) {
|
|
2088 warning("Attempt to allocate stack guard pages failed.");
|
|
2089 return;
|
|
2090 }
|
|
2091
|
|
2092 if (os::guard_memory((char *) low_addr, len)) {
|
|
2093 _stack_guard_state = stack_guard_enabled;
|
|
2094 } else {
|
|
2095 warning("Attempt to protect stack guard pages failed.");
|
|
2096 if (os::uncommit_memory((char *) low_addr, len)) {
|
|
2097 warning("Attempt to deallocate stack guard pages failed.");
|
|
2098 }
|
|
2099 }
|
|
2100 }
|
|
2101
|
|
2102 void JavaThread::remove_stack_guard_pages() {
|
|
2103 if (_stack_guard_state == stack_guard_unused) return;
|
|
2104 address low_addr = stack_base() - stack_size();
|
|
2105 size_t len = (StackYellowPages + StackRedPages) * os::vm_page_size();
|
|
2106
|
|
2107 if (os::allocate_stack_guard_pages()) {
|
|
2108 if (os::uncommit_memory((char *) low_addr, len)) {
|
|
2109 _stack_guard_state = stack_guard_unused;
|
|
2110 } else {
|
|
2111 warning("Attempt to deallocate stack guard pages failed.");
|
|
2112 }
|
|
2113 } else {
|
|
2114 if (_stack_guard_state == stack_guard_unused) return;
|
|
2115 if (os::unguard_memory((char *) low_addr, len)) {
|
|
2116 _stack_guard_state = stack_guard_unused;
|
|
2117 } else {
|
|
2118 warning("Attempt to unprotect stack guard pages failed.");
|
|
2119 }
|
|
2120 }
|
|
2121 }
|
|
2122
|
|
2123 void JavaThread::enable_stack_yellow_zone() {
|
|
2124 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
2125 assert(_stack_guard_state != stack_guard_enabled, "already enabled");
|
|
2126
|
|
2127 // The base notation is from the stacks point of view, growing downward.
|
|
2128 // We need to adjust it to work correctly with guard_memory()
|
|
2129 address base = stack_yellow_zone_base() - stack_yellow_zone_size();
|
|
2130
|
|
2131 guarantee(base < stack_base(),"Error calculating stack yellow zone");
|
|
2132 guarantee(base < os::current_stack_pointer(),"Error calculating stack yellow zone");
|
|
2133
|
|
2134 if (os::guard_memory((char *) base, stack_yellow_zone_size())) {
|
|
2135 _stack_guard_state = stack_guard_enabled;
|
|
2136 } else {
|
|
2137 warning("Attempt to guard stack yellow zone failed.");
|
|
2138 }
|
|
2139 enable_register_stack_guard();
|
|
2140 }
|
|
2141
|
|
2142 void JavaThread::disable_stack_yellow_zone() {
|
|
2143 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
2144 assert(_stack_guard_state != stack_guard_yellow_disabled, "already disabled");
|
|
2145
|
|
2146 // Simply return if called for a thread that does not use guard pages.
|
|
2147 if (_stack_guard_state == stack_guard_unused) return;
|
|
2148
|
|
2149 // The base notation is from the stacks point of view, growing downward.
|
|
2150 // We need to adjust it to work correctly with guard_memory()
|
|
2151 address base = stack_yellow_zone_base() - stack_yellow_zone_size();
|
|
2152
|
|
2153 if (os::unguard_memory((char *)base, stack_yellow_zone_size())) {
|
|
2154 _stack_guard_state = stack_guard_yellow_disabled;
|
|
2155 } else {
|
|
2156 warning("Attempt to unguard stack yellow zone failed.");
|
|
2157 }
|
|
2158 disable_register_stack_guard();
|
|
2159 }
|
|
2160
|
|
2161 void JavaThread::enable_stack_red_zone() {
|
|
2162 // The base notation is from the stacks point of view, growing downward.
|
|
2163 // We need to adjust it to work correctly with guard_memory()
|
|
2164 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
2165 address base = stack_red_zone_base() - stack_red_zone_size();
|
|
2166
|
|
2167 guarantee(base < stack_base(),"Error calculating stack red zone");
|
|
2168 guarantee(base < os::current_stack_pointer(),"Error calculating stack red zone");
|
|
2169
|
|
2170 if(!os::guard_memory((char *) base, stack_red_zone_size())) {
|
|
2171 warning("Attempt to guard stack red zone failed.");
|
|
2172 }
|
|
2173 }
|
|
2174
|
|
2175 void JavaThread::disable_stack_red_zone() {
|
|
2176 // The base notation is from the stacks point of view, growing downward.
|
|
2177 // We need to adjust it to work correctly with guard_memory()
|
|
2178 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
|
|
2179 address base = stack_red_zone_base() - stack_red_zone_size();
|
|
2180 if (!os::unguard_memory((char *)base, stack_red_zone_size())) {
|
|
2181 warning("Attempt to unguard stack red zone failed.");
|
|
2182 }
|
|
2183 }
|
|
2184
|
|
2185 void JavaThread::frames_do(void f(frame*, const RegisterMap* map)) {
|
|
2186 // ignore is there is no stack
|
|
2187 if (!has_last_Java_frame()) return;
|
|
2188 // traverse the stack frames. Starts from top frame.
|
|
2189 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
2190 frame* fr = fst.current();
|
|
2191 f(fr, fst.register_map());
|
|
2192 }
|
|
2193 }
|
|
2194
|
|
2195
|
|
2196 #ifndef PRODUCT
|
|
2197 // Deoptimization
|
|
2198 // Function for testing deoptimization
|
|
2199 void JavaThread::deoptimize() {
|
|
2200 // BiasedLocking needs an updated RegisterMap for the revoke monitors pass
|
|
2201 StackFrameStream fst(this, UseBiasedLocking);
|
|
2202 bool deopt = false; // Dump stack only if a deopt actually happens.
|
|
2203 bool only_at = strlen(DeoptimizeOnlyAt) > 0;
|
|
2204 // Iterate over all frames in the thread and deoptimize
|
|
2205 for(; !fst.is_done(); fst.next()) {
|
|
2206 if(fst.current()->can_be_deoptimized()) {
|
|
2207
|
|
2208 if (only_at) {
|
|
2209 // Deoptimize only at particular bcis. DeoptimizeOnlyAt
|
|
2210 // consists of comma or carriage return separated numbers so
|
|
2211 // search for the current bci in that string.
|
|
2212 address pc = fst.current()->pc();
|
|
2213 nmethod* nm = (nmethod*) fst.current()->cb();
|
|
2214 ScopeDesc* sd = nm->scope_desc_at( pc);
|
|
2215 char buffer[8];
|
|
2216 jio_snprintf(buffer, sizeof(buffer), "%d", sd->bci());
|
|
2217 size_t len = strlen(buffer);
|
|
2218 const char * found = strstr(DeoptimizeOnlyAt, buffer);
|
|
2219 while (found != NULL) {
|
|
2220 if ((found[len] == ',' || found[len] == '\n' || found[len] == '\0') &&
|
|
2221 (found == DeoptimizeOnlyAt || found[-1] == ',' || found[-1] == '\n')) {
|
|
2222 // Check that the bci found is bracketed by terminators.
|
|
2223 break;
|
|
2224 }
|
|
2225 found = strstr(found + 1, buffer);
|
|
2226 }
|
|
2227 if (!found) {
|
|
2228 continue;
|
|
2229 }
|
|
2230 }
|
|
2231
|
|
2232 if (DebugDeoptimization && !deopt) {
|
|
2233 deopt = true; // One-time only print before deopt
|
|
2234 tty->print_cr("[BEFORE Deoptimization]");
|
|
2235 trace_frames();
|
|
2236 trace_stack();
|
|
2237 }
|
|
2238 Deoptimization::deoptimize(this, *fst.current(), fst.register_map());
|
|
2239 }
|
|
2240 }
|
|
2241
|
|
2242 if (DebugDeoptimization && deopt) {
|
|
2243 tty->print_cr("[AFTER Deoptimization]");
|
|
2244 trace_frames();
|
|
2245 }
|
|
2246 }
|
|
2247
|
|
2248
|
|
2249 // Make zombies
|
|
2250 void JavaThread::make_zombies() {
|
|
2251 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
2252 if (fst.current()->can_be_deoptimized()) {
|
|
2253 // it is a Java nmethod
|
|
2254 nmethod* nm = CodeCache::find_nmethod(fst.current()->pc());
|
|
2255 nm->make_not_entrant();
|
|
2256 }
|
|
2257 }
|
|
2258 }
|
|
2259 #endif // PRODUCT
|
|
2260
|
|
2261
|
|
2262 void JavaThread::deoptimized_wrt_marked_nmethods() {
|
|
2263 if (!has_last_Java_frame()) return;
|
|
2264 // BiasedLocking needs an updated RegisterMap for the revoke monitors pass
|
|
2265 StackFrameStream fst(this, UseBiasedLocking);
|
|
2266 for(; !fst.is_done(); fst.next()) {
|
|
2267 if (fst.current()->should_be_deoptimized()) {
|
|
2268 Deoptimization::deoptimize(this, *fst.current(), fst.register_map());
|
|
2269 }
|
|
2270 }
|
|
2271 }
|
|
2272
|
|
2273
|
|
2274 // GC support
|
|
2275 static void frame_gc_epilogue(frame* f, const RegisterMap* map) { f->gc_epilogue(); }
|
|
2276
|
|
2277 void JavaThread::gc_epilogue() {
|
|
2278 frames_do(frame_gc_epilogue);
|
|
2279 }
|
|
2280
|
|
2281
|
|
2282 static void frame_gc_prologue(frame* f, const RegisterMap* map) { f->gc_prologue(); }
|
|
2283
|
|
2284 void JavaThread::gc_prologue() {
|
|
2285 frames_do(frame_gc_prologue);
|
|
2286 }
|
|
2287
|
|
2288
|
|
2289 void JavaThread::oops_do(OopClosure* f) {
|
|
2290 // The ThreadProfiler oops_do is done from FlatProfiler::oops_do
|
|
2291 // since there may be more than one thread using each ThreadProfiler.
|
|
2292
|
|
2293 // Traverse the GCHandles
|
|
2294 Thread::oops_do(f);
|
|
2295
|
|
2296 assert( (!has_last_Java_frame() && java_call_counter() == 0) ||
|
|
2297 (has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
|
|
2298
|
|
2299 if (has_last_Java_frame()) {
|
|
2300
|
|
2301 // Traverse the privileged stack
|
|
2302 if (_privileged_stack_top != NULL) {
|
|
2303 _privileged_stack_top->oops_do(f);
|
|
2304 }
|
|
2305
|
|
2306 // traverse the registered growable array
|
|
2307 if (_array_for_gc != NULL) {
|
|
2308 for (int index = 0; index < _array_for_gc->length(); index++) {
|
|
2309 f->do_oop(_array_for_gc->adr_at(index));
|
|
2310 }
|
|
2311 }
|
|
2312
|
|
2313 // Traverse the monitor chunks
|
|
2314 for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) {
|
|
2315 chunk->oops_do(f);
|
|
2316 }
|
|
2317
|
|
2318 // Traverse the execution stack
|
|
2319 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
2320 fst.current()->oops_do(f, fst.register_map());
|
|
2321 }
|
|
2322 }
|
|
2323
|
|
2324 // callee_target is never live across a gc point so NULL it here should
|
|
2325 // it still contain a methdOop.
|
|
2326
|
|
2327 set_callee_target(NULL);
|
|
2328
|
|
2329 assert(vframe_array_head() == NULL, "deopt in progress at a safepoint!");
|
|
2330 // If we have deferred set_locals there might be oops waiting to be
|
|
2331 // written
|
|
2332 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = deferred_locals();
|
|
2333 if (list != NULL) {
|
|
2334 for (int i = 0; i < list->length(); i++) {
|
|
2335 list->at(i)->oops_do(f);
|
|
2336 }
|
|
2337 }
|
|
2338
|
|
2339 // Traverse instance variables at the end since the GC may be moving things
|
|
2340 // around using this function
|
|
2341 f->do_oop((oop*) &_threadObj);
|
|
2342 f->do_oop((oop*) &_vm_result);
|
|
2343 f->do_oop((oop*) &_vm_result_2);
|
|
2344 f->do_oop((oop*) &_exception_oop);
|
|
2345 f->do_oop((oop*) &_pending_async_exception);
|
|
2346
|
|
2347 if (jvmti_thread_state() != NULL) {
|
|
2348 jvmti_thread_state()->oops_do(f);
|
|
2349 }
|
|
2350 }
|
|
2351
|
|
2352 void JavaThread::nmethods_do() {
|
|
2353 // Traverse the GCHandles
|
|
2354 Thread::nmethods_do();
|
|
2355
|
|
2356 assert( (!has_last_Java_frame() && java_call_counter() == 0) ||
|
|
2357 (has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
|
|
2358
|
|
2359 if (has_last_Java_frame()) {
|
|
2360 // Traverse the execution stack
|
|
2361 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
2362 fst.current()->nmethods_do();
|
|
2363 }
|
|
2364 }
|
|
2365 }
|
|
2366
|
|
2367 // Printing
|
|
2368 const char* _get_thread_state_name(JavaThreadState _thread_state) {
|
|
2369 switch (_thread_state) {
|
|
2370 case _thread_uninitialized: return "_thread_uninitialized";
|
|
2371 case _thread_new: return "_thread_new";
|
|
2372 case _thread_new_trans: return "_thread_new_trans";
|
|
2373 case _thread_in_native: return "_thread_in_native";
|
|
2374 case _thread_in_native_trans: return "_thread_in_native_trans";
|
|
2375 case _thread_in_vm: return "_thread_in_vm";
|
|
2376 case _thread_in_vm_trans: return "_thread_in_vm_trans";
|
|
2377 case _thread_in_Java: return "_thread_in_Java";
|
|
2378 case _thread_in_Java_trans: return "_thread_in_Java_trans";
|
|
2379 case _thread_blocked: return "_thread_blocked";
|
|
2380 case _thread_blocked_trans: return "_thread_blocked_trans";
|
|
2381 default: return "unknown thread state";
|
|
2382 }
|
|
2383 }
|
|
2384
|
|
2385 #ifndef PRODUCT
|
|
2386 void JavaThread::print_thread_state_on(outputStream *st) const {
|
|
2387 st->print_cr(" JavaThread state: %s", _get_thread_state_name(_thread_state));
|
|
2388 };
|
|
2389 void JavaThread::print_thread_state() const {
|
|
2390 print_thread_state_on(tty);
|
|
2391 };
|
|
2392 #endif // PRODUCT
|
|
2393
|
|
2394 // Called by Threads::print() for VM_PrintThreads operation
|
|
2395 void JavaThread::print_on(outputStream *st) const {
|
|
2396 st->print("\"%s\" ", get_thread_name());
|
|
2397 oop thread_oop = threadObj();
|
|
2398 if (thread_oop != NULL && java_lang_Thread::is_daemon(thread_oop)) st->print("daemon ");
|
|
2399 Thread::print_on(st);
|
|
2400 // print guess for valid stack memory region (assume 4K pages); helps lock debugging
|
|
2401 st->print_cr("[" INTPTR_FORMAT ".." INTPTR_FORMAT "]", (intptr_t)last_Java_sp() & ~right_n_bits(12), highest_lock());
|
|
2402 if (thread_oop != NULL && JDK_Version::is_gte_jdk15x_version()) {
|
|
2403 st->print_cr(" java.lang.Thread.State: %s", java_lang_Thread::thread_status_name(thread_oop));
|
|
2404 }
|
|
2405 #ifndef PRODUCT
|
|
2406 print_thread_state_on(st);
|
|
2407 _safepoint_state->print_on(st);
|
|
2408 #endif // PRODUCT
|
|
2409 }
|
|
2410
|
|
2411 // Called by fatal error handler. The difference between this and
|
|
2412 // JavaThread::print() is that we can't grab lock or allocate memory.
|
|
2413 void JavaThread::print_on_error(outputStream* st, char *buf, int buflen) const {
|
|
2414 st->print("JavaThread \"%s\"", get_thread_name_string(buf, buflen));
|
|
2415 oop thread_obj = threadObj();
|
|
2416 if (thread_obj != NULL) {
|
|
2417 if (java_lang_Thread::is_daemon(thread_obj)) st->print(" daemon");
|
|
2418 }
|
|
2419 st->print(" [");
|
|
2420 st->print("%s", _get_thread_state_name(_thread_state));
|
|
2421 if (osthread()) {
|
|
2422 st->print(", id=%d", osthread()->thread_id());
|
|
2423 }
|
|
2424 st->print(", stack(" PTR_FORMAT "," PTR_FORMAT ")",
|
|
2425 _stack_base - _stack_size, _stack_base);
|
|
2426 st->print("]");
|
|
2427 return;
|
|
2428 }
|
|
2429
|
|
2430 // Verification
|
|
2431
|
|
2432 static void frame_verify(frame* f, const RegisterMap *map) { f->verify(map); }
|
|
2433
|
|
2434 void JavaThread::verify() {
|
|
2435 // Verify oops in the thread.
|
|
2436 oops_do(&VerifyOopClosure::verify_oop);
|
|
2437
|
|
2438 // Verify the stack frames.
|
|
2439 frames_do(frame_verify);
|
|
2440 }
|
|
2441
|
|
2442 // CR 6300358 (sub-CR 2137150)
|
|
2443 // Most callers of this method assume that it can't return NULL but a
|
|
2444 // thread may not have a name whilst it is in the process of attaching to
|
|
2445 // the VM - see CR 6412693, and there are places where a JavaThread can be
|
|
2446 // seen prior to having it's threadObj set (eg JNI attaching threads and
|
|
2447 // if vm exit occurs during initialization). These cases can all be accounted
|
|
2448 // for such that this method never returns NULL.
|
|
2449 const char* JavaThread::get_thread_name() const {
|
|
2450 #ifdef ASSERT
|
|
2451 // early safepoints can hit while current thread does not yet have TLS
|
|
2452 if (!SafepointSynchronize::is_at_safepoint()) {
|
|
2453 Thread *cur = Thread::current();
|
|
2454 if (!(cur->is_Java_thread() && cur == this)) {
|
|
2455 // Current JavaThreads are allowed to get their own name without
|
|
2456 // the Threads_lock.
|
|
2457 assert_locked_or_safepoint(Threads_lock);
|
|
2458 }
|
|
2459 }
|
|
2460 #endif // ASSERT
|
|
2461 return get_thread_name_string();
|
|
2462 }
|
|
2463
|
|
2464 // Returns a non-NULL representation of this thread's name, or a suitable
|
|
2465 // descriptive string if there is no set name
|
|
2466 const char* JavaThread::get_thread_name_string(char* buf, int buflen) const {
|
|
2467 const char* name_str;
|
|
2468 oop thread_obj = threadObj();
|
|
2469 if (thread_obj != NULL) {
|
|
2470 typeArrayOop name = java_lang_Thread::name(thread_obj);
|
|
2471 if (name != NULL) {
|
|
2472 if (buf == NULL) {
|
|
2473 name_str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
|
|
2474 }
|
|
2475 else {
|
|
2476 name_str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length(), buf, buflen);
|
|
2477 }
|
|
2478 }
|
|
2479 else if (is_attaching()) { // workaround for 6412693 - see 6404306
|
|
2480 name_str = "<no-name - thread is attaching>";
|
|
2481 }
|
|
2482 else {
|
|
2483 name_str = Thread::name();
|
|
2484 }
|
|
2485 }
|
|
2486 else {
|
|
2487 name_str = Thread::name();
|
|
2488 }
|
|
2489 assert(name_str != NULL, "unexpected NULL thread name");
|
|
2490 return name_str;
|
|
2491 }
|
|
2492
|
|
2493
|
|
2494 const char* JavaThread::get_threadgroup_name() const {
|
|
2495 debug_only(if (JavaThread::current() != this) assert_locked_or_safepoint(Threads_lock);)
|
|
2496 oop thread_obj = threadObj();
|
|
2497 if (thread_obj != NULL) {
|
|
2498 oop thread_group = java_lang_Thread::threadGroup(thread_obj);
|
|
2499 if (thread_group != NULL) {
|
|
2500 typeArrayOop name = java_lang_ThreadGroup::name(thread_group);
|
|
2501 // ThreadGroup.name can be null
|
|
2502 if (name != NULL) {
|
|
2503 const char* str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
|
|
2504 return str;
|
|
2505 }
|
|
2506 }
|
|
2507 }
|
|
2508 return NULL;
|
|
2509 }
|
|
2510
|
|
2511 const char* JavaThread::get_parent_name() const {
|
|
2512 debug_only(if (JavaThread::current() != this) assert_locked_or_safepoint(Threads_lock);)
|
|
2513 oop thread_obj = threadObj();
|
|
2514 if (thread_obj != NULL) {
|
|
2515 oop thread_group = java_lang_Thread::threadGroup(thread_obj);
|
|
2516 if (thread_group != NULL) {
|
|
2517 oop parent = java_lang_ThreadGroup::parent(thread_group);
|
|
2518 if (parent != NULL) {
|
|
2519 typeArrayOop name = java_lang_ThreadGroup::name(parent);
|
|
2520 // ThreadGroup.name can be null
|
|
2521 if (name != NULL) {
|
|
2522 const char* str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
|
|
2523 return str;
|
|
2524 }
|
|
2525 }
|
|
2526 }
|
|
2527 }
|
|
2528 return NULL;
|
|
2529 }
|
|
2530
|
|
2531 ThreadPriority JavaThread::java_priority() const {
|
|
2532 oop thr_oop = threadObj();
|
|
2533 if (thr_oop == NULL) return NormPriority; // Bootstrapping
|
|
2534 ThreadPriority priority = java_lang_Thread::priority(thr_oop);
|
|
2535 assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
|
|
2536 return priority;
|
|
2537 }
|
|
2538
|
|
2539 void JavaThread::prepare(jobject jni_thread, ThreadPriority prio) {
|
|
2540
|
|
2541 assert(Threads_lock->owner() == Thread::current(), "must have threads lock");
|
|
2542 // Link Java Thread object <-> C++ Thread
|
|
2543
|
|
2544 // Get the C++ thread object (an oop) from the JNI handle (a jthread)
|
|
2545 // and put it into a new Handle. The Handle "thread_oop" can then
|
|
2546 // be used to pass the C++ thread object to other methods.
|
|
2547
|
|
2548 // Set the Java level thread object (jthread) field of the
|
|
2549 // new thread (a JavaThread *) to C++ thread object using the
|
|
2550 // "thread_oop" handle.
|
|
2551
|
|
2552 // Set the thread field (a JavaThread *) of the
|
|
2553 // oop representing the java_lang_Thread to the new thread (a JavaThread *).
|
|
2554
|
|
2555 Handle thread_oop(Thread::current(),
|
|
2556 JNIHandles::resolve_non_null(jni_thread));
|
|
2557 assert(instanceKlass::cast(thread_oop->klass())->is_linked(),
|
|
2558 "must be initialized");
|
|
2559 set_threadObj(thread_oop());
|
|
2560 java_lang_Thread::set_thread(thread_oop(), this);
|
|
2561
|
|
2562 if (prio == NoPriority) {
|
|
2563 prio = java_lang_Thread::priority(thread_oop());
|
|
2564 assert(prio != NoPriority, "A valid priority should be present");
|
|
2565 }
|
|
2566
|
|
2567 // Push the Java priority down to the native thread; needs Threads_lock
|
|
2568 Thread::set_priority(this, prio);
|
|
2569
|
|
2570 // Add the new thread to the Threads list and set it in motion.
|
|
2571 // We must have threads lock in order to call Threads::add.
|
|
2572 // It is crucial that we do not block before the thread is
|
|
2573 // added to the Threads list for if a GC happens, then the java_thread oop
|
|
2574 // will not be visited by GC.
|
|
2575 Threads::add(this);
|
|
2576 }
|
|
2577
|
|
2578 oop JavaThread::current_park_blocker() {
|
|
2579 // Support for JSR-166 locks
|
|
2580 oop thread_oop = threadObj();
|
|
2581 if (thread_oop != NULL && JDK_Version::supports_thread_park_blocker()) {
|
|
2582 return java_lang_Thread::park_blocker(thread_oop);
|
|
2583 }
|
|
2584 return NULL;
|
|
2585 }
|
|
2586
|
|
2587
|
|
2588 void JavaThread::print_stack_on(outputStream* st) {
|
|
2589 if (!has_last_Java_frame()) return;
|
|
2590 ResourceMark rm;
|
|
2591 HandleMark hm;
|
|
2592
|
|
2593 RegisterMap reg_map(this);
|
|
2594 vframe* start_vf = last_java_vframe(®_map);
|
|
2595 int count = 0;
|
|
2596 for (vframe* f = start_vf; f; f = f->sender() ) {
|
|
2597 if (f->is_java_frame()) {
|
|
2598 javaVFrame* jvf = javaVFrame::cast(f);
|
|
2599 java_lang_Throwable::print_stack_element(st, jvf->method(), jvf->bci());
|
|
2600
|
|
2601 // Print out lock information
|
|
2602 if (JavaMonitorsInStackTrace) {
|
|
2603 jvf->print_lock_info_on(st, count);
|
|
2604 }
|
|
2605 } else {
|
|
2606 // Ignore non-Java frames
|
|
2607 }
|
|
2608
|
|
2609 // Bail-out case for too deep stacks
|
|
2610 count++;
|
|
2611 if (MaxJavaStackTraceDepth == count) return;
|
|
2612 }
|
|
2613 }
|
|
2614
|
|
2615
|
|
2616 // JVMTI PopFrame support
|
|
2617 void JavaThread::popframe_preserve_args(ByteSize size_in_bytes, void* start) {
|
|
2618 assert(_popframe_preserved_args == NULL, "should not wipe out old PopFrame preserved arguments");
|
|
2619 if (in_bytes(size_in_bytes) != 0) {
|
|
2620 _popframe_preserved_args = NEW_C_HEAP_ARRAY(char, in_bytes(size_in_bytes));
|
|
2621 _popframe_preserved_args_size = in_bytes(size_in_bytes);
|
|
2622 Copy::conjoint_bytes(start, _popframe_preserved_args, _popframe_preserved_args_size);
|
|
2623 }
|
|
2624 }
|
|
2625
|
|
2626 void* JavaThread::popframe_preserved_args() {
|
|
2627 return _popframe_preserved_args;
|
|
2628 }
|
|
2629
|
|
2630 ByteSize JavaThread::popframe_preserved_args_size() {
|
|
2631 return in_ByteSize(_popframe_preserved_args_size);
|
|
2632 }
|
|
2633
|
|
2634 WordSize JavaThread::popframe_preserved_args_size_in_words() {
|
|
2635 int sz = in_bytes(popframe_preserved_args_size());
|
|
2636 assert(sz % wordSize == 0, "argument size must be multiple of wordSize");
|
|
2637 return in_WordSize(sz / wordSize);
|
|
2638 }
|
|
2639
|
|
2640 void JavaThread::popframe_free_preserved_args() {
|
|
2641 assert(_popframe_preserved_args != NULL, "should not free PopFrame preserved arguments twice");
|
|
2642 FREE_C_HEAP_ARRAY(char, (char*) _popframe_preserved_args);
|
|
2643 _popframe_preserved_args = NULL;
|
|
2644 _popframe_preserved_args_size = 0;
|
|
2645 }
|
|
2646
|
|
2647 #ifndef PRODUCT
|
|
2648
|
|
2649 void JavaThread::trace_frames() {
|
|
2650 tty->print_cr("[Describe stack]");
|
|
2651 int frame_no = 1;
|
|
2652 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
|
|
2653 tty->print(" %d. ", frame_no++);
|
|
2654 fst.current()->print_value_on(tty,this);
|
|
2655 tty->cr();
|
|
2656 }
|
|
2657 }
|
|
2658
|
|
2659
|
|
2660 void JavaThread::trace_stack_from(vframe* start_vf) {
|
|
2661 ResourceMark rm;
|
|
2662 int vframe_no = 1;
|
|
2663 for (vframe* f = start_vf; f; f = f->sender() ) {
|
|
2664 if (f->is_java_frame()) {
|
|
2665 javaVFrame::cast(f)->print_activation(vframe_no++);
|
|
2666 } else {
|
|
2667 f->print();
|
|
2668 }
|
|
2669 if (vframe_no > StackPrintLimit) {
|
|
2670 tty->print_cr("...<more frames>...");
|
|
2671 return;
|
|
2672 }
|
|
2673 }
|
|
2674 }
|
|
2675
|
|
2676
|
|
2677 void JavaThread::trace_stack() {
|
|
2678 if (!has_last_Java_frame()) return;
|
|
2679 ResourceMark rm;
|
|
2680 HandleMark hm;
|
|
2681 RegisterMap reg_map(this);
|
|
2682 trace_stack_from(last_java_vframe(®_map));
|
|
2683 }
|
|
2684
|
|
2685
|
|
2686 #endif // PRODUCT
|
|
2687
|
|
2688
|
|
2689 javaVFrame* JavaThread::last_java_vframe(RegisterMap *reg_map) {
|
|
2690 assert(reg_map != NULL, "a map must be given");
|
|
2691 frame f = last_frame();
|
|
2692 for (vframe* vf = vframe::new_vframe(&f, reg_map, this); vf; vf = vf->sender() ) {
|
|
2693 if (vf->is_java_frame()) return javaVFrame::cast(vf);
|
|
2694 }
|
|
2695 return NULL;
|
|
2696 }
|
|
2697
|
|
2698
|
|
2699 klassOop JavaThread::security_get_caller_class(int depth) {
|
|
2700 vframeStream vfst(this);
|
|
2701 vfst.security_get_caller_frame(depth);
|
|
2702 if (!vfst.at_end()) {
|
|
2703 return vfst.method()->method_holder();
|
|
2704 }
|
|
2705 return NULL;
|
|
2706 }
|
|
2707
|
|
2708 static void compiler_thread_entry(JavaThread* thread, TRAPS) {
|
|
2709 assert(thread->is_Compiler_thread(), "must be compiler thread");
|
|
2710 CompileBroker::compiler_thread_loop();
|
|
2711 }
|
|
2712
|
|
2713 // Create a CompilerThread
|
|
2714 CompilerThread::CompilerThread(CompileQueue* queue, CompilerCounters* counters)
|
|
2715 : JavaThread(&compiler_thread_entry) {
|
|
2716 _env = NULL;
|
|
2717 _log = NULL;
|
|
2718 _task = NULL;
|
|
2719 _queue = queue;
|
|
2720 _counters = counters;
|
|
2721
|
|
2722 #ifndef PRODUCT
|
|
2723 _ideal_graph_printer = NULL;
|
|
2724 #endif
|
|
2725 }
|
|
2726
|
|
2727
|
|
2728 // ======= Threads ========
|
|
2729
|
|
2730 // The Threads class links together all active threads, and provides
|
|
2731 // operations over all threads. It is protected by its own Mutex
|
|
2732 // lock, which is also used in other contexts to protect thread
|
|
2733 // operations from having the thread being operated on from exiting
|
|
2734 // and going away unexpectedly (e.g., safepoint synchronization)
|
|
2735
|
|
2736 JavaThread* Threads::_thread_list = NULL;
|
|
2737 int Threads::_number_of_threads = 0;
|
|
2738 int Threads::_number_of_non_daemon_threads = 0;
|
|
2739 int Threads::_return_code = 0;
|
|
2740 size_t JavaThread::_stack_size_at_create = 0;
|
|
2741
|
|
2742 // All JavaThreads
|
|
2743 #define ALL_JAVA_THREADS(X) for (JavaThread* X = _thread_list; X; X = X->next())
|
|
2744
|
|
2745 void os_stream();
|
|
2746
|
|
2747 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system)
|
|
2748 void Threads::threads_do(ThreadClosure* tc) {
|
|
2749 assert_locked_or_safepoint(Threads_lock);
|
|
2750 // ALL_JAVA_THREADS iterates through all JavaThreads
|
|
2751 ALL_JAVA_THREADS(p) {
|
|
2752 tc->do_thread(p);
|
|
2753 }
|
|
2754 // Someday we could have a table or list of all non-JavaThreads.
|
|
2755 // For now, just manually iterate through them.
|
|
2756 tc->do_thread(VMThread::vm_thread());
|
|
2757 Universe::heap()->gc_threads_do(tc);
|
|
2758 tc->do_thread(WatcherThread::watcher_thread());
|
|
2759 // If CompilerThreads ever become non-JavaThreads, add them here
|
|
2760 }
|
|
2761
|
|
2762 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
|
|
2763
|
|
2764 // Check version
|
|
2765 if (!is_supported_jni_version(args->version)) return JNI_EVERSION;
|
|
2766
|
|
2767 // Initialize the output stream module
|
|
2768 ostream_init();
|
|
2769
|
|
2770 // Process java launcher properties.
|
|
2771 Arguments::process_sun_java_launcher_properties(args);
|
|
2772
|
|
2773 // Initialize the os module before using TLS
|
|
2774 os::init();
|
|
2775
|
|
2776 // Initialize system properties.
|
|
2777 Arguments::init_system_properties();
|
|
2778
|
|
2779 // Parse arguments
|
|
2780 jint parse_result = Arguments::parse(args);
|
|
2781 if (parse_result != JNI_OK) return parse_result;
|
|
2782
|
|
2783 if (PauseAtStartup) {
|
|
2784 os::pause();
|
|
2785 }
|
|
2786
|
|
2787 HS_DTRACE_PROBE(hotspot, vm__init__begin);
|
|
2788
|
|
2789 // Record VM creation timing statistics
|
|
2790 TraceVmCreationTime create_vm_timer;
|
|
2791 create_vm_timer.start();
|
|
2792
|
|
2793 // Timing (must come after argument parsing)
|
|
2794 TraceTime timer("Create VM", TraceStartupTime);
|
|
2795
|
|
2796 // Initialize the os module after parsing the args
|
|
2797 jint os_init_2_result = os::init_2();
|
|
2798 if (os_init_2_result != JNI_OK) return os_init_2_result;
|
|
2799
|
|
2800 // Initialize output stream logging
|
|
2801 ostream_init_log();
|
|
2802
|
|
2803 // Convert -Xrun to -agentlib: if there is no JVM_OnLoad
|
|
2804 // Must be before create_vm_init_agents()
|
|
2805 if (Arguments::init_libraries_at_startup()) {
|
|
2806 convert_vm_init_libraries_to_agents();
|
|
2807 }
|
|
2808
|
|
2809 // Launch -agentlib/-agentpath and converted -Xrun agents
|
|
2810 if (Arguments::init_agents_at_startup()) {
|
|
2811 create_vm_init_agents();
|
|
2812 }
|
|
2813
|
|
2814 // Initialize Threads state
|
|
2815 _thread_list = NULL;
|
|
2816 _number_of_threads = 0;
|
|
2817 _number_of_non_daemon_threads = 0;
|
|
2818
|
|
2819 // Initialize TLS
|
|
2820 ThreadLocalStorage::init();
|
|
2821
|
|
2822 // Initialize global data structures and create system classes in heap
|
|
2823 vm_init_globals();
|
|
2824
|
|
2825 // Attach the main thread to this os thread
|
|
2826 JavaThread* main_thread = new JavaThread();
|
|
2827 main_thread->set_thread_state(_thread_in_vm);
|
|
2828 // must do this before set_active_handles and initialize_thread_local_storage
|
|
2829 // Note: on solaris initialize_thread_local_storage() will (indirectly)
|
|
2830 // change the stack size recorded here to one based on the java thread
|
|
2831 // stacksize. This adjusted size is what is used to figure the placement
|
|
2832 // of the guard pages.
|
|
2833 main_thread->record_stack_base_and_size();
|
|
2834 main_thread->initialize_thread_local_storage();
|
|
2835
|
|
2836 main_thread->set_active_handles(JNIHandleBlock::allocate_block());
|
|
2837
|
|
2838 if (!main_thread->set_as_starting_thread()) {
|
|
2839 vm_shutdown_during_initialization(
|
|
2840 "Failed necessary internal allocation. Out of swap space");
|
|
2841 delete main_thread;
|
|
2842 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
|
|
2843 return JNI_ENOMEM;
|
|
2844 }
|
|
2845
|
|
2846 // Enable guard page *after* os::create_main_thread(), otherwise it would
|
|
2847 // crash Linux VM, see notes in os_linux.cpp.
|
|
2848 main_thread->create_stack_guard_pages();
|
|
2849
|
|
2850 // Initialize Java-Leve synchronization subsystem
|
|
2851 ObjectSynchronizer::Initialize() ;
|
|
2852
|
|
2853 // Initialize global modules
|
|
2854 jint status = init_globals();
|
|
2855 if (status != JNI_OK) {
|
|
2856 delete main_thread;
|
|
2857 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
|
|
2858 return status;
|
|
2859 }
|
|
2860
|
|
2861 HandleMark hm;
|
|
2862
|
|
2863 { MutexLocker mu(Threads_lock);
|
|
2864 Threads::add(main_thread);
|
|
2865 }
|
|
2866
|
|
2867 // Any JVMTI raw monitors entered in onload will transition into
|
|
2868 // real raw monitor. VM is setup enough here for raw monitor enter.
|
|
2869 JvmtiExport::transition_pending_onload_raw_monitors();
|
|
2870
|
|
2871 if (VerifyBeforeGC &&
|
|
2872 Universe::heap()->total_collections() >= VerifyGCStartAt) {
|
|
2873 Universe::heap()->prepare_for_verify();
|
|
2874 Universe::verify(); // make sure we're starting with a clean slate
|
|
2875 }
|
|
2876
|
|
2877 // Create the VMThread
|
|
2878 { TraceTime timer("Start VMThread", TraceStartupTime);
|
|
2879 VMThread::create();
|
|
2880 Thread* vmthread = VMThread::vm_thread();
|
|
2881
|
|
2882 if (!os::create_thread(vmthread, os::vm_thread))
|
|
2883 vm_exit_during_initialization("Cannot create VM thread. Out of system resources.");
|
|
2884
|
|
2885 // Wait for the VM thread to become ready, and VMThread::run to initialize
|
|
2886 // Monitors can have spurious returns, must always check another state flag
|
|
2887 {
|
|
2888 MutexLocker ml(Notify_lock);
|
|
2889 os::start_thread(vmthread);
|
|
2890 while (vmthread->active_handles() == NULL) {
|
|
2891 Notify_lock->wait();
|
|
2892 }
|
|
2893 }
|
|
2894 }
|
|
2895
|
|
2896 assert (Universe::is_fully_initialized(), "not initialized");
|
|
2897 EXCEPTION_MARK;
|
|
2898
|
|
2899 // At this point, the Universe is initialized, but we have not executed
|
|
2900 // any byte code. Now is a good time (the only time) to dump out the
|
|
2901 // internal state of the JVM for sharing.
|
|
2902
|
|
2903 if (DumpSharedSpaces) {
|
|
2904 Universe::heap()->preload_and_dump(CHECK_0);
|
|
2905 ShouldNotReachHere();
|
|
2906 }
|
|
2907
|
|
2908 // Always call even when there are not JVMTI environments yet, since environments
|
|
2909 // may be attached late and JVMTI must track phases of VM execution
|
|
2910 JvmtiExport::enter_start_phase();
|
|
2911
|
|
2912 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
|
|
2913 JvmtiExport::post_vm_start();
|
|
2914
|
|
2915 {
|
|
2916 TraceTime timer("Initialize java.lang classes", TraceStartupTime);
|
|
2917
|
|
2918 if (EagerXrunInit && Arguments::init_libraries_at_startup()) {
|
|
2919 create_vm_init_libraries();
|
|
2920 }
|
|
2921
|
|
2922 if (InitializeJavaLangString) {
|
|
2923 initialize_class(vmSymbolHandles::java_lang_String(), CHECK_0);
|
|
2924 } else {
|
|
2925 warning("java.lang.String not initialized");
|
|
2926 }
|
|
2927
|
|
2928 // Initialize java_lang.System (needed before creating the thread)
|
|
2929 if (InitializeJavaLangSystem) {
|
|
2930 initialize_class(vmSymbolHandles::java_lang_System(), CHECK_0);
|
|
2931 initialize_class(vmSymbolHandles::java_lang_ThreadGroup(), CHECK_0);
|
|
2932 Handle thread_group = create_initial_thread_group(CHECK_0);
|
|
2933 Universe::set_main_thread_group(thread_group());
|
|
2934 initialize_class(vmSymbolHandles::java_lang_Thread(), CHECK_0);
|
|
2935 oop thread_object = create_initial_thread(thread_group, main_thread, CHECK_0);
|
|
2936 main_thread->set_threadObj(thread_object);
|
|
2937 // Set thread status to running since main thread has
|
|
2938 // been started and running.
|
|
2939 java_lang_Thread::set_thread_status(thread_object,
|
|
2940 java_lang_Thread::RUNNABLE);
|
|
2941
|
|
2942 // The VM preresolve methods to these classes. Make sure that get initialized
|
|
2943 initialize_class(vmSymbolHandles::java_lang_reflect_Method(), CHECK_0);
|
|
2944 initialize_class(vmSymbolHandles::java_lang_ref_Finalizer(), CHECK_0);
|
|
2945 // The VM creates & returns objects of this class. Make sure it's initialized.
|
|
2946 initialize_class(vmSymbolHandles::java_lang_Class(), CHECK_0);
|
|
2947 call_initializeSystemClass(CHECK_0);
|
|
2948 } else {
|
|
2949 warning("java.lang.System not initialized");
|
|
2950 }
|
|
2951
|
|
2952 // an instance of OutOfMemory exception has been allocated earlier
|
|
2953 if (InitializeJavaLangExceptionsErrors) {
|
|
2954 initialize_class(vmSymbolHandles::java_lang_OutOfMemoryError(), CHECK_0);
|
|
2955 initialize_class(vmSymbolHandles::java_lang_NullPointerException(), CHECK_0);
|
|
2956 initialize_class(vmSymbolHandles::java_lang_ClassCastException(), CHECK_0);
|
|
2957 initialize_class(vmSymbolHandles::java_lang_ArrayStoreException(), CHECK_0);
|
|
2958 initialize_class(vmSymbolHandles::java_lang_ArithmeticException(), CHECK_0);
|
|
2959 initialize_class(vmSymbolHandles::java_lang_StackOverflowError(), CHECK_0);
|
|
2960 initialize_class(vmSymbolHandles::java_lang_IllegalMonitorStateException(), CHECK_0);
|
|
2961 } else {
|
|
2962 warning("java.lang.OutOfMemoryError has not been initialized");
|
|
2963 warning("java.lang.NullPointerException has not been initialized");
|
|
2964 warning("java.lang.ClassCastException has not been initialized");
|
|
2965 warning("java.lang.ArrayStoreException has not been initialized");
|
|
2966 warning("java.lang.ArithmeticException has not been initialized");
|
|
2967 warning("java.lang.StackOverflowError has not been initialized");
|
|
2968 }
|
|
2969 }
|
|
2970
|
|
2971 // See : bugid 4211085.
|
|
2972 // Background : the static initializer of java.lang.Compiler tries to read
|
|
2973 // property"java.compiler" and read & write property "java.vm.info".
|
|
2974 // When a security manager is installed through the command line
|
|
2975 // option "-Djava.security.manager", the above properties are not
|
|
2976 // readable and the static initializer for java.lang.Compiler fails
|
|
2977 // resulting in a NoClassDefFoundError. This can happen in any
|
|
2978 // user code which calls methods in java.lang.Compiler.
|
|
2979 // Hack : the hack is to pre-load and initialize this class, so that only
|
|
2980 // system domains are on the stack when the properties are read.
|
|
2981 // Currently even the AWT code has calls to methods in java.lang.Compiler.
|
|
2982 // On the classic VM, java.lang.Compiler is loaded very early to load the JIT.
|
|
2983 // Future Fix : the best fix is to grant everyone permissions to read "java.compiler" and
|
|
2984 // read and write"java.vm.info" in the default policy file. See bugid 4211383
|
|
2985 // Once that is done, we should remove this hack.
|
|
2986 initialize_class(vmSymbolHandles::java_lang_Compiler(), CHECK_0);
|
|
2987
|
|
2988 // More hackery - the static initializer of java.lang.Compiler adds the string "nojit" to
|
|
2989 // the java.vm.info property if no jit gets loaded through java.lang.Compiler (the hotspot
|
|
2990 // compiler does not get loaded through java.lang.Compiler). "java -version" with the
|
|
2991 // hotspot vm says "nojit" all the time which is confusing. So, we reset it here.
|
|
2992 // This should also be taken out as soon as 4211383 gets fixed.
|
|
2993 reset_vm_info_property(CHECK_0);
|
|
2994
|
|
2995 quicken_jni_functions();
|
|
2996
|
|
2997 // Set flag that basic initialization has completed. Used by exceptions and various
|
|
2998 // debug stuff, that does not work until all basic classes have been initialized.
|
|
2999 set_init_completed();
|
|
3000
|
|
3001 HS_DTRACE_PROBE(hotspot, vm__init__end);
|
|
3002
|
|
3003 // record VM initialization completion time
|
|
3004 Management::record_vm_init_completed();
|
|
3005
|
|
3006 // Compute system loader. Note that this has to occur after set_init_completed, since
|
|
3007 // valid exceptions may be thrown in the process.
|
|
3008 // Note that we do not use CHECK_0 here since we are inside an EXCEPTION_MARK and
|
|
3009 // set_init_completed has just been called, causing exceptions not to be shortcut
|
|
3010 // anymore. We call vm_exit_during_initialization directly instead.
|
|
3011 SystemDictionary::compute_java_system_loader(THREAD);
|
|
3012 if (HAS_PENDING_EXCEPTION) {
|
|
3013 vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
|
|
3014 }
|
|
3015
|
|
3016 #ifndef SERIALGC
|
|
3017 // Support for ConcurrentMarkSweep. This should be cleaned up
|
|
3018 // and better encapsulated. XXX YSR
|
|
3019 if (UseConcMarkSweepGC) {
|
|
3020 ConcurrentMarkSweepThread::makeSurrogateLockerThread(THREAD);
|
|
3021 if (HAS_PENDING_EXCEPTION) {
|
|
3022 vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
|
|
3023 }
|
|
3024 }
|
|
3025 #endif // SERIALGC
|
|
3026
|
|
3027 // Always call even when there are not JVMTI environments yet, since environments
|
|
3028 // may be attached late and JVMTI must track phases of VM execution
|
|
3029 JvmtiExport::enter_live_phase();
|
|
3030
|
|
3031 // Signal Dispatcher needs to be started before VMInit event is posted
|
|
3032 os::signal_init();
|
|
3033
|
|
3034 // Start Attach Listener if +StartAttachListener or it can't be started lazily
|
|
3035 if (!DisableAttachMechanism) {
|
|
3036 if (StartAttachListener || AttachListener::init_at_startup()) {
|
|
3037 AttachListener::init();
|
|
3038 }
|
|
3039 }
|
|
3040
|
|
3041 // Launch -Xrun agents
|
|
3042 // Must be done in the JVMTI live phase so that for backward compatibility the JDWP
|
|
3043 // back-end can launch with -Xdebug -Xrunjdwp.
|
|
3044 if (!EagerXrunInit && Arguments::init_libraries_at_startup()) {
|
|
3045 create_vm_init_libraries();
|
|
3046 }
|
|
3047
|
|
3048 // Notify JVMTI agents that VM initialization is complete - nop if no agents.
|
|
3049 JvmtiExport::post_vm_initialized();
|
|
3050
|
|
3051 Chunk::start_chunk_pool_cleaner_task();
|
|
3052
|
|
3053 // initialize compiler(s)
|
|
3054 CompileBroker::compilation_init();
|
|
3055
|
|
3056 Management::initialize(THREAD);
|
|
3057 if (HAS_PENDING_EXCEPTION) {
|
|
3058 // management agent fails to start possibly due to
|
|
3059 // configuration problem and is responsible for printing
|
|
3060 // stack trace if appropriate. Simply exit VM.
|
|
3061 vm_exit(1);
|
|
3062 }
|
|
3063
|
|
3064 if (Arguments::has_profile()) FlatProfiler::engage(main_thread, true);
|
|
3065 if (Arguments::has_alloc_profile()) AllocationProfiler::engage();
|
|
3066 if (MemProfiling) MemProfiler::engage();
|
|
3067 StatSampler::engage();
|
|
3068 if (CheckJNICalls) JniPeriodicChecker::engage();
|
|
3069 if (CacheTimeMillis) TimeMillisUpdateTask::engage();
|
|
3070
|
|
3071 BiasedLocking::init();
|
|
3072
|
|
3073
|
|
3074 // Start up the WatcherThread if there are any periodic tasks
|
|
3075 // NOTE: All PeriodicTasks should be registered by now. If they
|
|
3076 // aren't, late joiners might appear to start slowly (we might
|
|
3077 // take a while to process their first tick).
|
|
3078 if (PeriodicTask::num_tasks() > 0) {
|
|
3079 WatcherThread::start();
|
|
3080 }
|
|
3081
|
|
3082 create_vm_timer.end();
|
|
3083 return JNI_OK;
|
|
3084 }
|
|
3085
|
|
3086 // type for the Agent_OnLoad and JVM_OnLoad entry points
|
|
3087 extern "C" {
|
|
3088 typedef jint (JNICALL *OnLoadEntry_t)(JavaVM *, char *, void *);
|
|
3089 }
|
|
3090 // Find a command line agent library and return its entry point for
|
|
3091 // -agentlib: -agentpath: -Xrun
|
|
3092 // num_symbol_entries must be passed-in since only the caller knows the number of symbols in the array.
|
|
3093 static OnLoadEntry_t lookup_on_load(AgentLibrary* agent, const char *on_load_symbols[], size_t num_symbol_entries) {
|
|
3094 OnLoadEntry_t on_load_entry = NULL;
|
|
3095 void *library = agent->os_lib(); // check if we have looked it up before
|
|
3096
|
|
3097 if (library == NULL) {
|
|
3098 char buffer[JVM_MAXPATHLEN];
|
|
3099 char ebuf[1024];
|
|
3100 const char *name = agent->name();
|
|
3101
|
|
3102 if (agent->is_absolute_path()) {
|
|
3103 library = hpi::dll_load(name, ebuf, sizeof ebuf);
|
|
3104 if (library == NULL) {
|
|
3105 // If we can't find the agent, exit.
|
|
3106 vm_exit_during_initialization("Could not find agent library in absolute path", name);
|
|
3107 }
|
|
3108 } else {
|
|
3109 // Try to load the agent from the standard dll directory
|
|
3110 hpi::dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), name);
|
|
3111 library = hpi::dll_load(buffer, ebuf, sizeof ebuf);
|
|
3112 #ifdef KERNEL
|
|
3113 // Download instrument dll
|
|
3114 if (library == NULL && strcmp(name, "instrument") == 0) {
|
|
3115 char *props = Arguments::get_kernel_properties();
|
|
3116 char *home = Arguments::get_java_home();
|
|
3117 const char *fmt = "%s/bin/java %s -Dkernel.background.download=false"
|
|
3118 " sun.jkernel.DownloadManager -download client_jvm";
|
|
3119 int length = strlen(props) + strlen(home) + strlen(fmt) + 1;
|
|
3120 char *cmd = AllocateHeap(length);
|
|
3121 jio_snprintf(cmd, length, fmt, home, props);
|
|
3122 int status = os::fork_and_exec(cmd);
|
|
3123 FreeHeap(props);
|
|
3124 FreeHeap(cmd);
|
|
3125 if (status == -1) {
|
|
3126 warning(cmd);
|
|
3127 vm_exit_during_initialization("fork_and_exec failed: %s",
|
|
3128 strerror(errno));
|
|
3129 }
|
|
3130 // when this comes back the instrument.dll should be where it belongs.
|
|
3131 library = hpi::dll_load(buffer, ebuf, sizeof ebuf);
|
|
3132 }
|
|
3133 #endif // KERNEL
|
|
3134 if (library == NULL) { // Try the local directory
|
|
3135 char ns[1] = {0};
|
|
3136 hpi::dll_build_name(buffer, sizeof(buffer), ns, name);
|
|
3137 library = hpi::dll_load(buffer, ebuf, sizeof ebuf);
|
|
3138 if (library == NULL) {
|
|
3139 // If we can't find the agent, exit.
|
|
3140 vm_exit_during_initialization("Could not find agent library on the library path or in the local directory", name);
|
|
3141 }
|
|
3142 }
|
|
3143 }
|
|
3144 agent->set_os_lib(library);
|
|
3145 }
|
|
3146
|
|
3147 // Find the OnLoad function.
|
|
3148 for (size_t symbol_index = 0; symbol_index < num_symbol_entries; symbol_index++) {
|
|
3149 on_load_entry = CAST_TO_FN_PTR(OnLoadEntry_t, hpi::dll_lookup(library, on_load_symbols[symbol_index]));
|
|
3150 if (on_load_entry != NULL) break;
|
|
3151 }
|
|
3152 return on_load_entry;
|
|
3153 }
|
|
3154
|
|
3155 // Find the JVM_OnLoad entry point
|
|
3156 static OnLoadEntry_t lookup_jvm_on_load(AgentLibrary* agent) {
|
|
3157 const char *on_load_symbols[] = JVM_ONLOAD_SYMBOLS;
|
|
3158 return lookup_on_load(agent, on_load_symbols, sizeof(on_load_symbols) / sizeof(char*));
|
|
3159 }
|
|
3160
|
|
3161 // Find the Agent_OnLoad entry point
|
|
3162 static OnLoadEntry_t lookup_agent_on_load(AgentLibrary* agent) {
|
|
3163 const char *on_load_symbols[] = AGENT_ONLOAD_SYMBOLS;
|
|
3164 return lookup_on_load(agent, on_load_symbols, sizeof(on_load_symbols) / sizeof(char*));
|
|
3165 }
|
|
3166
|
|
3167 // For backwards compatibility with -Xrun
|
|
3168 // Convert libraries with no JVM_OnLoad, but which have Agent_OnLoad to be
|
|
3169 // treated like -agentpath:
|
|
3170 // Must be called before agent libraries are created
|
|
3171 void Threads::convert_vm_init_libraries_to_agents() {
|
|
3172 AgentLibrary* agent;
|
|
3173 AgentLibrary* next;
|
|
3174
|
|
3175 for (agent = Arguments::libraries(); agent != NULL; agent = next) {
|
|
3176 next = agent->next(); // cache the next agent now as this agent may get moved off this list
|
|
3177 OnLoadEntry_t on_load_entry = lookup_jvm_on_load(agent);
|
|
3178
|
|
3179 // If there is an JVM_OnLoad function it will get called later,
|
|
3180 // otherwise see if there is an Agent_OnLoad
|
|
3181 if (on_load_entry == NULL) {
|
|
3182 on_load_entry = lookup_agent_on_load(agent);
|
|
3183 if (on_load_entry != NULL) {
|
|
3184 // switch it to the agent list -- so that Agent_OnLoad will be called,
|
|
3185 // JVM_OnLoad won't be attempted and Agent_OnUnload will
|
|
3186 Arguments::convert_library_to_agent(agent);
|
|
3187 } else {
|
|
3188 vm_exit_during_initialization("Could not find JVM_OnLoad or Agent_OnLoad function in the library", agent->name());
|
|
3189 }
|
|
3190 }
|
|
3191 }
|
|
3192 }
|
|
3193
|
|
3194 // Create agents for -agentlib: -agentpath: and converted -Xrun
|
|
3195 // Invokes Agent_OnLoad
|
|
3196 // Called very early -- before JavaThreads exist
|
|
3197 void Threads::create_vm_init_agents() {
|
|
3198 extern struct JavaVM_ main_vm;
|
|
3199 AgentLibrary* agent;
|
|
3200
|
|
3201 JvmtiExport::enter_onload_phase();
|
|
3202 for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
|
|
3203 OnLoadEntry_t on_load_entry = lookup_agent_on_load(agent);
|
|
3204
|
|
3205 if (on_load_entry != NULL) {
|
|
3206 // Invoke the Agent_OnLoad function
|
|
3207 jint err = (*on_load_entry)(&main_vm, agent->options(), NULL);
|
|
3208 if (err != JNI_OK) {
|
|
3209 vm_exit_during_initialization("agent library failed to init", agent->name());
|
|
3210 }
|
|
3211 } else {
|
|
3212 vm_exit_during_initialization("Could not find Agent_OnLoad function in the agent library", agent->name());
|
|
3213 }
|
|
3214 }
|
|
3215 JvmtiExport::enter_primordial_phase();
|
|
3216 }
|
|
3217
|
|
3218 extern "C" {
|
|
3219 typedef void (JNICALL *Agent_OnUnload_t)(JavaVM *);
|
|
3220 }
|
|
3221
|
|
3222 void Threads::shutdown_vm_agents() {
|
|
3223 // Send any Agent_OnUnload notifications
|
|
3224 const char *on_unload_symbols[] = AGENT_ONUNLOAD_SYMBOLS;
|
|
3225 extern struct JavaVM_ main_vm;
|
|
3226 for (AgentLibrary* agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
|
|
3227
|
|
3228 // Find the Agent_OnUnload function.
|
|
3229 for (uint symbol_index = 0; symbol_index < ARRAY_SIZE(on_unload_symbols); symbol_index++) {
|
|
3230 Agent_OnUnload_t unload_entry = CAST_TO_FN_PTR(Agent_OnUnload_t,
|
|
3231 hpi::dll_lookup(agent->os_lib(), on_unload_symbols[symbol_index]));
|
|
3232
|
|
3233 // Invoke the Agent_OnUnload function
|
|
3234 if (unload_entry != NULL) {
|
|
3235 JavaThread* thread = JavaThread::current();
|
|
3236 ThreadToNativeFromVM ttn(thread);
|
|
3237 HandleMark hm(thread);
|
|
3238 (*unload_entry)(&main_vm);
|
|
3239 break;
|
|
3240 }
|
|
3241 }
|
|
3242 }
|
|
3243 }
|
|
3244
|
|
3245 // Called for after the VM is initialized for -Xrun libraries which have not been converted to agent libraries
|
|
3246 // Invokes JVM_OnLoad
|
|
3247 void Threads::create_vm_init_libraries() {
|
|
3248 extern struct JavaVM_ main_vm;
|
|
3249 AgentLibrary* agent;
|
|
3250
|
|
3251 for (agent = Arguments::libraries(); agent != NULL; agent = agent->next()) {
|
|
3252 OnLoadEntry_t on_load_entry = lookup_jvm_on_load(agent);
|
|
3253
|
|
3254 if (on_load_entry != NULL) {
|
|
3255 // Invoke the JVM_OnLoad function
|
|
3256 JavaThread* thread = JavaThread::current();
|
|
3257 ThreadToNativeFromVM ttn(thread);
|
|
3258 HandleMark hm(thread);
|
|
3259 jint err = (*on_load_entry)(&main_vm, agent->options(), NULL);
|
|
3260 if (err != JNI_OK) {
|
|
3261 vm_exit_during_initialization("-Xrun library failed to init", agent->name());
|
|
3262 }
|
|
3263 } else {
|
|
3264 vm_exit_during_initialization("Could not find JVM_OnLoad function in -Xrun library", agent->name());
|
|
3265 }
|
|
3266 }
|
|
3267 }
|
|
3268
|
|
3269 // Last thread running calls java.lang.Shutdown.shutdown()
|
|
3270 void JavaThread::invoke_shutdown_hooks() {
|
|
3271 HandleMark hm(this);
|
|
3272
|
|
3273 // We could get here with a pending exception, if so clear it now.
|
|
3274 if (this->has_pending_exception()) {
|
|
3275 this->clear_pending_exception();
|
|
3276 }
|
|
3277
|
|
3278 EXCEPTION_MARK;
|
|
3279 klassOop k =
|
|
3280 SystemDictionary::resolve_or_null(vmSymbolHandles::java_lang_Shutdown(),
|
|
3281 THREAD);
|
|
3282 if (k != NULL) {
|
|
3283 // SystemDictionary::resolve_or_null will return null if there was
|
|
3284 // an exception. If we cannot load the Shutdown class, just don't
|
|
3285 // call Shutdown.shutdown() at all. This will mean the shutdown hooks
|
|
3286 // and finalizers (if runFinalizersOnExit is set) won't be run.
|
|
3287 // Note that if a shutdown hook was registered or runFinalizersOnExit
|
|
3288 // was called, the Shutdown class would have already been loaded
|
|
3289 // (Runtime.addShutdownHook and runFinalizersOnExit will load it).
|
|
3290 instanceKlassHandle shutdown_klass (THREAD, k);
|
|
3291 JavaValue result(T_VOID);
|
|
3292 JavaCalls::call_static(&result,
|
|
3293 shutdown_klass,
|
|
3294 vmSymbolHandles::shutdown_method_name(),
|
|
3295 vmSymbolHandles::void_method_signature(),
|
|
3296 THREAD);
|
|
3297 }
|
|
3298 CLEAR_PENDING_EXCEPTION;
|
|
3299 }
|
|
3300
|
|
3301 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when
|
|
3302 // the program falls off the end of main(). Another VM exit path is through
|
|
3303 // vm_exit() when the program calls System.exit() to return a value or when
|
|
3304 // there is a serious error in VM. The two shutdown paths are not exactly
|
|
3305 // the same, but they share Shutdown.shutdown() at Java level and before_exit()
|
|
3306 // and VM_Exit op at VM level.
|
|
3307 //
|
|
3308 // Shutdown sequence:
|
|
3309 // + Wait until we are the last non-daemon thread to execute
|
|
3310 // <-- every thing is still working at this moment -->
|
|
3311 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level
|
|
3312 // shutdown hooks, run finalizers if finalization-on-exit
|
|
3313 // + Call before_exit(), prepare for VM exit
|
|
3314 // > run VM level shutdown hooks (they are registered through JVM_OnExit(),
|
|
3315 // currently the only user of this mechanism is File.deleteOnExit())
|
|
3316 // > stop flat profiler, StatSampler, watcher thread, CMS threads,
|
|
3317 // post thread end and vm death events to JVMTI,
|
|
3318 // stop signal thread
|
|
3319 // + Call JavaThread::exit(), it will:
|
|
3320 // > release JNI handle blocks, remove stack guard pages
|
|
3321 // > remove this thread from Threads list
|
|
3322 // <-- no more Java code from this thread after this point -->
|
|
3323 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop
|
|
3324 // the compiler threads at safepoint
|
|
3325 // <-- do not use anything that could get blocked by Safepoint -->
|
|
3326 // + Disable tracing at JNI/JVM barriers
|
|
3327 // + Set _vm_exited flag for threads that are still running native code
|
|
3328 // + Delete this thread
|
|
3329 // + Call exit_globals()
|
|
3330 // > deletes tty
|
|
3331 // > deletes PerfMemory resources
|
|
3332 // + Return to caller
|
|
3333
|
|
3334 bool Threads::destroy_vm() {
|
|
3335 JavaThread* thread = JavaThread::current();
|
|
3336
|
|
3337 // Wait until we are the last non-daemon thread to execute
|
|
3338 { MutexLocker nu(Threads_lock);
|
|
3339 while (Threads::number_of_non_daemon_threads() > 1 )
|
|
3340 // This wait should make safepoint checks, wait without a timeout,
|
|
3341 // and wait as a suspend-equivalent condition.
|
|
3342 //
|
|
3343 // Note: If the FlatProfiler is running and this thread is waiting
|
|
3344 // for another non-daemon thread to finish, then the FlatProfiler
|
|
3345 // is waiting for the external suspend request on this thread to
|
|
3346 // complete. wait_for_ext_suspend_completion() will eventually
|
|
3347 // timeout, but that takes time. Making this wait a suspend-
|
|
3348 // equivalent condition solves that timeout problem.
|
|
3349 //
|
|
3350 Threads_lock->wait(!Mutex::_no_safepoint_check_flag, 0,
|
|
3351 Mutex::_as_suspend_equivalent_flag);
|
|
3352 }
|
|
3353
|
|
3354 // Hang forever on exit if we are reporting an error.
|
|
3355 if (ShowMessageBoxOnError && is_error_reported()) {
|
|
3356 os::infinite_sleep();
|
|
3357 }
|
|
3358
|
|
3359 if (JDK_Version::is_jdk12x_version()) {
|
|
3360 // We are the last thread running, so check if finalizers should be run.
|
|
3361 // For 1.3 or later this is done in thread->invoke_shutdown_hooks()
|
|
3362 HandleMark rm(thread);
|
|
3363 Universe::run_finalizers_on_exit();
|
|
3364 } else {
|
|
3365 // run Java level shutdown hooks
|
|
3366 thread->invoke_shutdown_hooks();
|
|
3367 }
|
|
3368
|
|
3369 before_exit(thread);
|
|
3370
|
|
3371 thread->exit(true);
|
|
3372
|
|
3373 // Stop VM thread.
|
|
3374 {
|
|
3375 // 4945125 The vm thread comes to a safepoint during exit.
|
|
3376 // GC vm_operations can get caught at the safepoint, and the
|
|
3377 // heap is unparseable if they are caught. Grab the Heap_lock
|
|
3378 // to prevent this. The GC vm_operations will not be able to
|
|
3379 // queue until after the vm thread is dead.
|
|
3380 MutexLocker ml(Heap_lock);
|
|
3381
|
|
3382 VMThread::wait_for_vm_thread_exit();
|
|
3383 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint");
|
|
3384 VMThread::destroy();
|
|
3385 }
|
|
3386
|
|
3387 // clean up ideal graph printers
|
|
3388 #if defined(COMPILER2) && !defined(PRODUCT)
|
|
3389 IdealGraphPrinter::clean_up();
|
|
3390 #endif
|
|
3391
|
|
3392 // Now, all Java threads are gone except daemon threads. Daemon threads
|
|
3393 // running Java code or in VM are stopped by the Safepoint. However,
|
|
3394 // daemon threads executing native code are still running. But they
|
|
3395 // will be stopped at native=>Java/VM barriers. Note that we can't
|
|
3396 // simply kill or suspend them, as it is inherently deadlock-prone.
|
|
3397
|
|
3398 #ifndef PRODUCT
|
|
3399 // disable function tracing at JNI/JVM barriers
|
|
3400 TraceHPI = false;
|
|
3401 TraceJNICalls = false;
|
|
3402 TraceJVMCalls = false;
|
|
3403 TraceRuntimeCalls = false;
|
|
3404 #endif
|
|
3405
|
|
3406 VM_Exit::set_vm_exited();
|
|
3407
|
|
3408 notify_vm_shutdown();
|
|
3409
|
|
3410 delete thread;
|
|
3411
|
|
3412 // exit_globals() will delete tty
|
|
3413 exit_globals();
|
|
3414
|
|
3415 return true;
|
|
3416 }
|
|
3417
|
|
3418
|
|
3419 jboolean Threads::is_supported_jni_version_including_1_1(jint version) {
|
|
3420 if (version == JNI_VERSION_1_1) return JNI_TRUE;
|
|
3421 return is_supported_jni_version(version);
|
|
3422 }
|
|
3423
|
|
3424
|
|
3425 jboolean Threads::is_supported_jni_version(jint version) {
|
|
3426 if (version == JNI_VERSION_1_2) return JNI_TRUE;
|
|
3427 if (version == JNI_VERSION_1_4) return JNI_TRUE;
|
|
3428 if (version == JNI_VERSION_1_6) return JNI_TRUE;
|
|
3429 return JNI_FALSE;
|
|
3430 }
|
|
3431
|
|
3432
|
|
3433 void Threads::add(JavaThread* p, bool force_daemon) {
|
|
3434 // The threads lock must be owned at this point
|
|
3435 assert_locked_or_safepoint(Threads_lock);
|
|
3436 p->set_next(_thread_list);
|
|
3437 _thread_list = p;
|
|
3438 _number_of_threads++;
|
|
3439 oop threadObj = p->threadObj();
|
|
3440 bool daemon = true;
|
|
3441 // Bootstrapping problem: threadObj can be null for initial
|
|
3442 // JavaThread (or for threads attached via JNI)
|
|
3443 if ((!force_daemon) && (threadObj == NULL || !java_lang_Thread::is_daemon(threadObj))) {
|
|
3444 _number_of_non_daemon_threads++;
|
|
3445 daemon = false;
|
|
3446 }
|
|
3447
|
|
3448 ThreadService::add_thread(p, daemon);
|
|
3449
|
|
3450 // Possible GC point.
|
|
3451 Events::log("Thread added: " INTPTR_FORMAT, p);
|
|
3452 }
|
|
3453
|
|
3454 void Threads::remove(JavaThread* p) {
|
|
3455 // Extra scope needed for Thread_lock, so we can check
|
|
3456 // that we do not remove thread without safepoint code notice
|
|
3457 { MutexLocker ml(Threads_lock);
|
|
3458
|
|
3459 assert(includes(p), "p must be present");
|
|
3460
|
|
3461 JavaThread* current = _thread_list;
|
|
3462 JavaThread* prev = NULL;
|
|
3463
|
|
3464 while (current != p) {
|
|
3465 prev = current;
|
|
3466 current = current->next();
|
|
3467 }
|
|
3468
|
|
3469 if (prev) {
|
|
3470 prev->set_next(current->next());
|
|
3471 } else {
|
|
3472 _thread_list = p->next();
|
|
3473 }
|
|
3474 _number_of_threads--;
|
|
3475 oop threadObj = p->threadObj();
|
|
3476 bool daemon = true;
|
|
3477 if (threadObj == NULL || !java_lang_Thread::is_daemon(threadObj)) {
|
|
3478 _number_of_non_daemon_threads--;
|
|
3479 daemon = false;
|
|
3480
|
|
3481 // Only one thread left, do a notify on the Threads_lock so a thread waiting
|
|
3482 // on destroy_vm will wake up.
|
|
3483 if (number_of_non_daemon_threads() == 1)
|
|
3484 Threads_lock->notify_all();
|
|
3485 }
|
|
3486 ThreadService::remove_thread(p, daemon);
|
|
3487
|
|
3488 // Make sure that safepoint code disregard this thread. This is needed since
|
|
3489 // the thread might mess around with locks after this point. This can cause it
|
|
3490 // to do callbacks into the safepoint code. However, the safepoint code is not aware
|
|
3491 // of this thread since it is removed from the queue.
|
|
3492 p->set_terminated_value();
|
|
3493 } // unlock Threads_lock
|
|
3494
|
|
3495 // Since Events::log uses a lock, we grab it outside the Threads_lock
|
|
3496 Events::log("Thread exited: " INTPTR_FORMAT, p);
|
|
3497 }
|
|
3498
|
|
3499 // Threads_lock must be held when this is called (or must be called during a safepoint)
|
|
3500 bool Threads::includes(JavaThread* p) {
|
|
3501 assert(Threads_lock->is_locked(), "sanity check");
|
|
3502 ALL_JAVA_THREADS(q) {
|
|
3503 if (q == p ) {
|
|
3504 return true;
|
|
3505 }
|
|
3506 }
|
|
3507 return false;
|
|
3508 }
|
|
3509
|
|
3510 // Operations on the Threads list for GC. These are not explicitly locked,
|
|
3511 // but the garbage collector must provide a safe context for them to run.
|
|
3512 // In particular, these things should never be called when the Threads_lock
|
|
3513 // is held by some other thread. (Note: the Safepoint abstraction also
|
|
3514 // uses the Threads_lock to gurantee this property. It also makes sure that
|
|
3515 // all threads gets blocked when exiting or starting).
|
|
3516
|
|
3517 void Threads::oops_do(OopClosure* f) {
|
|
3518 ALL_JAVA_THREADS(p) {
|
|
3519 p->oops_do(f);
|
|
3520 }
|
|
3521 VMThread::vm_thread()->oops_do(f);
|
|
3522 }
|
|
3523
|
|
3524 void Threads::possibly_parallel_oops_do(OopClosure* f) {
|
|
3525 // Introduce a mechanism allowing parallel threads to claim threads as
|
|
3526 // root groups. Overhead should be small enough to use all the time,
|
|
3527 // even in sequential code.
|
|
3528 SharedHeap* sh = SharedHeap::heap();
|
|
3529 bool is_par = (sh->n_par_threads() > 0);
|
|
3530 int cp = SharedHeap::heap()->strong_roots_parity();
|
|
3531 ALL_JAVA_THREADS(p) {
|
|
3532 if (p->claim_oops_do(is_par, cp)) {
|
|
3533 p->oops_do(f);
|
|
3534 }
|
|
3535 }
|
|
3536 VMThread* vmt = VMThread::vm_thread();
|
|
3537 if (vmt->claim_oops_do(is_par, cp))
|
|
3538 vmt->oops_do(f);
|
|
3539 }
|
|
3540
|
|
3541 #ifndef SERIALGC
|
|
3542 // Used by ParallelScavenge
|
|
3543 void Threads::create_thread_roots_tasks(GCTaskQueue* q) {
|
|
3544 ALL_JAVA_THREADS(p) {
|
|
3545 q->enqueue(new ThreadRootsTask(p));
|
|
3546 }
|
|
3547 q->enqueue(new ThreadRootsTask(VMThread::vm_thread()));
|
|
3548 }
|
|
3549
|
|
3550 // Used by Parallel Old
|
|
3551 void Threads::create_thread_roots_marking_tasks(GCTaskQueue* q) {
|
|
3552 ALL_JAVA_THREADS(p) {
|
|
3553 q->enqueue(new ThreadRootsMarkingTask(p));
|
|
3554 }
|
|
3555 q->enqueue(new ThreadRootsMarkingTask(VMThread::vm_thread()));
|
|
3556 }
|
|
3557 #endif // SERIALGC
|
|
3558
|
|
3559 void Threads::nmethods_do() {
|
|
3560 ALL_JAVA_THREADS(p) {
|
|
3561 p->nmethods_do();
|
|
3562 }
|
|
3563 VMThread::vm_thread()->nmethods_do();
|
|
3564 }
|
|
3565
|
|
3566 void Threads::gc_epilogue() {
|
|
3567 ALL_JAVA_THREADS(p) {
|
|
3568 p->gc_epilogue();
|
|
3569 }
|
|
3570 }
|
|
3571
|
|
3572 void Threads::gc_prologue() {
|
|
3573 ALL_JAVA_THREADS(p) {
|
|
3574 p->gc_prologue();
|
|
3575 }
|
|
3576 }
|
|
3577
|
|
3578 void Threads::deoptimized_wrt_marked_nmethods() {
|
|
3579 ALL_JAVA_THREADS(p) {
|
|
3580 p->deoptimized_wrt_marked_nmethods();
|
|
3581 }
|
|
3582 }
|
|
3583
|
|
3584
|
|
3585 // Get count Java threads that are waiting to enter the specified monitor.
|
|
3586 GrowableArray<JavaThread*>* Threads::get_pending_threads(int count,
|
|
3587 address monitor, bool doLock) {
|
|
3588 assert(doLock || SafepointSynchronize::is_at_safepoint(),
|
|
3589 "must grab Threads_lock or be at safepoint");
|
|
3590 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count);
|
|
3591
|
|
3592 int i = 0;
|
|
3593 {
|
|
3594 MutexLockerEx ml(doLock ? Threads_lock : NULL);
|
|
3595 ALL_JAVA_THREADS(p) {
|
|
3596 if (p->is_Compiler_thread()) continue;
|
|
3597
|
|
3598 address pending = (address)p->current_pending_monitor();
|
|
3599 if (pending == monitor) { // found a match
|
|
3600 if (i < count) result->append(p); // save the first count matches
|
|
3601 i++;
|
|
3602 }
|
|
3603 }
|
|
3604 }
|
|
3605 return result;
|
|
3606 }
|
|
3607
|
|
3608
|
|
3609 JavaThread *Threads::owning_thread_from_monitor_owner(address owner, bool doLock) {
|
|
3610 assert(doLock ||
|
|
3611 Threads_lock->owned_by_self() ||
|
|
3612 SafepointSynchronize::is_at_safepoint(),
|
|
3613 "must grab Threads_lock or be at safepoint");
|
|
3614
|
|
3615 // NULL owner means not locked so we can skip the search
|
|
3616 if (owner == NULL) return NULL;
|
|
3617
|
|
3618 {
|
|
3619 MutexLockerEx ml(doLock ? Threads_lock : NULL);
|
|
3620 ALL_JAVA_THREADS(p) {
|
|
3621 // first, see if owner is the address of a Java thread
|
|
3622 if (owner == (address)p) return p;
|
|
3623 }
|
|
3624 }
|
|
3625 assert(UseHeavyMonitors == false, "Did not find owning Java thread with UseHeavyMonitors enabled");
|
|
3626 if (UseHeavyMonitors) return NULL;
|
|
3627
|
|
3628 //
|
|
3629 // If we didn't find a matching Java thread and we didn't force use of
|
|
3630 // heavyweight monitors, then the owner is the stack address of the
|
|
3631 // Lock Word in the owning Java thread's stack.
|
|
3632 //
|
|
3633 // We can't use Thread::is_lock_owned() or Thread::lock_is_in_stack() because
|
|
3634 // those routines rely on the "current" stack pointer. That would be our
|
|
3635 // stack pointer which is not relevant to the question. Instead we use the
|
|
3636 // highest lock ever entered by the thread and find the thread that is
|
|
3637 // higher than and closest to our target stack address.
|
|
3638 //
|
|
3639 address least_diff = 0;
|
|
3640 bool least_diff_initialized = false;
|
|
3641 JavaThread* the_owner = NULL;
|
|
3642 {
|
|
3643 MutexLockerEx ml(doLock ? Threads_lock : NULL);
|
|
3644 ALL_JAVA_THREADS(q) {
|
|
3645 address addr = q->highest_lock();
|
|
3646 if (addr == NULL || addr < owner) continue; // thread has entered no monitors or is too low
|
|
3647 address diff = (address)(addr - owner);
|
|
3648 if (!least_diff_initialized || diff < least_diff) {
|
|
3649 least_diff_initialized = true;
|
|
3650 least_diff = diff;
|
|
3651 the_owner = q;
|
|
3652 }
|
|
3653 }
|
|
3654 }
|
|
3655 assert(the_owner != NULL, "Did not find owning Java thread for lock word address");
|
|
3656 return the_owner;
|
|
3657 }
|
|
3658
|
|
3659 // Threads::print_on() is called at safepoint by VM_PrintThreads operation.
|
|
3660 void Threads::print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks) {
|
|
3661 char buf[32];
|
|
3662 st->print_cr(os::local_time_string(buf, sizeof(buf)));
|
|
3663
|
|
3664 st->print_cr("Full thread dump %s (%s %s):",
|
|
3665 Abstract_VM_Version::vm_name(),
|
|
3666 Abstract_VM_Version::vm_release(),
|
|
3667 Abstract_VM_Version::vm_info_string()
|
|
3668 );
|
|
3669 st->cr();
|
|
3670
|
|
3671 #ifndef SERIALGC
|
|
3672 // Dump concurrent locks
|
|
3673 ConcurrentLocksDump concurrent_locks;
|
|
3674 if (print_concurrent_locks) {
|
|
3675 concurrent_locks.dump_at_safepoint();
|
|
3676 }
|
|
3677 #endif // SERIALGC
|
|
3678
|
|
3679 ALL_JAVA_THREADS(p) {
|
|
3680 ResourceMark rm;
|
|
3681 p->print_on(st);
|
|
3682 if (print_stacks) {
|
|
3683 if (internal_format) {
|
|
3684 p->trace_stack();
|
|
3685 } else {
|
|
3686 p->print_stack_on(st);
|
|
3687 }
|
|
3688 }
|
|
3689 st->cr();
|
|
3690 #ifndef SERIALGC
|
|
3691 if (print_concurrent_locks) {
|
|
3692 concurrent_locks.print_locks_on(p, st);
|
|
3693 }
|
|
3694 #endif // SERIALGC
|
|
3695 }
|
|
3696
|
|
3697 VMThread::vm_thread()->print_on(st);
|
|
3698 st->cr();
|
|
3699 Universe::heap()->print_gc_threads_on(st);
|
|
3700 WatcherThread* wt = WatcherThread::watcher_thread();
|
|
3701 if (wt != NULL) wt->print_on(st);
|
|
3702 st->cr();
|
|
3703 CompileBroker::print_compiler_threads_on(st);
|
|
3704 st->flush();
|
|
3705 }
|
|
3706
|
|
3707 // Threads::print_on_error() is called by fatal error handler. It's possible
|
|
3708 // that VM is not at safepoint and/or current thread is inside signal handler.
|
|
3709 // Don't print stack trace, as the stack may not be walkable. Don't allocate
|
|
3710 // memory (even in resource area), it might deadlock the error handler.
|
|
3711 void Threads::print_on_error(outputStream* st, Thread* current, char* buf, int buflen) {
|
|
3712 bool found_current = false;
|
|
3713 st->print_cr("Java Threads: ( => current thread )");
|
|
3714 ALL_JAVA_THREADS(thread) {
|
|
3715 bool is_current = (current == thread);
|
|
3716 found_current = found_current || is_current;
|
|
3717
|
|
3718 st->print("%s", is_current ? "=>" : " ");
|
|
3719
|
|
3720 st->print(PTR_FORMAT, thread);
|
|
3721 st->print(" ");
|
|
3722 thread->print_on_error(st, buf, buflen);
|
|
3723 st->cr();
|
|
3724 }
|
|
3725 st->cr();
|
|
3726
|
|
3727 st->print_cr("Other Threads:");
|
|
3728 if (VMThread::vm_thread()) {
|
|
3729 bool is_current = (current == VMThread::vm_thread());
|
|
3730 found_current = found_current || is_current;
|
|
3731 st->print("%s", current == VMThread::vm_thread() ? "=>" : " ");
|
|
3732
|
|
3733 st->print(PTR_FORMAT, VMThread::vm_thread());
|
|
3734 st->print(" ");
|
|
3735 VMThread::vm_thread()->print_on_error(st, buf, buflen);
|
|
3736 st->cr();
|
|
3737 }
|
|
3738 WatcherThread* wt = WatcherThread::watcher_thread();
|
|
3739 if (wt != NULL) {
|
|
3740 bool is_current = (current == wt);
|
|
3741 found_current = found_current || is_current;
|
|
3742 st->print("%s", is_current ? "=>" : " ");
|
|
3743
|
|
3744 st->print(PTR_FORMAT, wt);
|
|
3745 st->print(" ");
|
|
3746 wt->print_on_error(st, buf, buflen);
|
|
3747 st->cr();
|
|
3748 }
|
|
3749 if (!found_current) {
|
|
3750 st->cr();
|
|
3751 st->print("=>" PTR_FORMAT " (exited) ", current);
|
|
3752 current->print_on_error(st, buf, buflen);
|
|
3753 st->cr();
|
|
3754 }
|
|
3755 }
|
|
3756
|
|
3757
|
|
3758 // Lifecycle management for TSM ParkEvents.
|
|
3759 // ParkEvents are type-stable (TSM).
|
|
3760 // In our particular implementation they happen to be immortal.
|
|
3761 //
|
|
3762 // We manage concurrency on the FreeList with a CAS-based
|
|
3763 // detach-modify-reattach idiom that avoids the ABA problems
|
|
3764 // that would otherwise be present in a simple CAS-based
|
|
3765 // push-pop implementation. (push-one and pop-all)
|
|
3766 //
|
|
3767 // Caveat: Allocate() and Release() may be called from threads
|
|
3768 // other than the thread associated with the Event!
|
|
3769 // If we need to call Allocate() when running as the thread in
|
|
3770 // question then look for the PD calls to initialize native TLS.
|
|
3771 // Native TLS (Win32/Linux/Solaris) can only be initialized or
|
|
3772 // accessed by the associated thread.
|
|
3773 // See also pd_initialize().
|
|
3774 //
|
|
3775 // Note that we could defer associating a ParkEvent with a thread
|
|
3776 // until the 1st time the thread calls park(). unpark() calls to
|
|
3777 // an unprovisioned thread would be ignored. The first park() call
|
|
3778 // for a thread would allocate and associate a ParkEvent and return
|
|
3779 // immediately.
|
|
3780
|
|
3781 volatile int ParkEvent::ListLock = 0 ;
|
|
3782 ParkEvent * volatile ParkEvent::FreeList = NULL ;
|
|
3783
|
|
3784 ParkEvent * ParkEvent::Allocate (Thread * t) {
|
|
3785 // In rare cases -- JVM_RawMonitor* operations -- we can find t == null.
|
|
3786 ParkEvent * ev ;
|
|
3787
|
|
3788 // Start by trying to recycle an existing but unassociated
|
|
3789 // ParkEvent from the global free list.
|
|
3790 for (;;) {
|
|
3791 ev = FreeList ;
|
|
3792 if (ev == NULL) break ;
|
|
3793 // 1: Detach - sequester or privatize the list
|
|
3794 // Tantamount to ev = Swap (&FreeList, NULL)
|
|
3795 if (Atomic::cmpxchg_ptr (NULL, &FreeList, ev) != ev) {
|
|
3796 continue ;
|
|
3797 }
|
|
3798
|
|
3799 // We've detached the list. The list in-hand is now
|
|
3800 // local to this thread. This thread can operate on the
|
|
3801 // list without risk of interference from other threads.
|
|
3802 // 2: Extract -- pop the 1st element from the list.
|
|
3803 ParkEvent * List = ev->FreeNext ;
|
|
3804 if (List == NULL) break ;
|
|
3805 for (;;) {
|
|
3806 // 3: Try to reattach the residual list
|
|
3807 guarantee (List != NULL, "invariant") ;
|
|
3808 ParkEvent * Arv = (ParkEvent *) Atomic::cmpxchg_ptr (List, &FreeList, NULL) ;
|
|
3809 if (Arv == NULL) break ;
|
|
3810
|
|
3811 // New nodes arrived. Try to detach the recent arrivals.
|
|
3812 if (Atomic::cmpxchg_ptr (NULL, &FreeList, Arv) != Arv) {
|
|
3813 continue ;
|
|
3814 }
|
|
3815 guarantee (Arv != NULL, "invariant") ;
|
|
3816 // 4: Merge Arv into List
|
|
3817 ParkEvent * Tail = List ;
|
|
3818 while (Tail->FreeNext != NULL) Tail = Tail->FreeNext ;
|
|
3819 Tail->FreeNext = Arv ;
|
|
3820 }
|
|
3821 break ;
|
|
3822 }
|
|
3823
|
|
3824 if (ev != NULL) {
|
|
3825 guarantee (ev->AssociatedWith == NULL, "invariant") ;
|
|
3826 } else {
|
|
3827 // Do this the hard way -- materialize a new ParkEvent.
|
|
3828 // In rare cases an allocating thread might detach a long list --
|
|
3829 // installing null into FreeList -- and then stall or be obstructed.
|
|
3830 // A 2nd thread calling Allocate() would see FreeList == null.
|
|
3831 // The list held privately by the 1st thread is unavailable to the 2nd thread.
|
|
3832 // In that case the 2nd thread would have to materialize a new ParkEvent,
|
|
3833 // even though free ParkEvents existed in the system. In this case we end up
|
|
3834 // with more ParkEvents in circulation than we need, but the race is
|
|
3835 // rare and the outcome is benign. Ideally, the # of extant ParkEvents
|
|
3836 // is equal to the maximum # of threads that existed at any one time.
|
|
3837 // Because of the race mentioned above, segments of the freelist
|
|
3838 // can be transiently inaccessible. At worst we may end up with the
|
|
3839 // # of ParkEvents in circulation slightly above the ideal.
|
|
3840 // Note that if we didn't have the TSM/immortal constraint, then
|
|
3841 // when reattaching, above, we could trim the list.
|
|
3842 ev = new ParkEvent () ;
|
|
3843 guarantee ((intptr_t(ev) & 0xFF) == 0, "invariant") ;
|
|
3844 }
|
|
3845 ev->reset() ; // courtesy to caller
|
|
3846 ev->AssociatedWith = t ; // Associate ev with t
|
|
3847 ev->FreeNext = NULL ;
|
|
3848 return ev ;
|
|
3849 }
|
|
3850
|
|
3851 void ParkEvent::Release (ParkEvent * ev) {
|
|
3852 if (ev == NULL) return ;
|
|
3853 guarantee (ev->FreeNext == NULL , "invariant") ;
|
|
3854 ev->AssociatedWith = NULL ;
|
|
3855 for (;;) {
|
|
3856 // Push ev onto FreeList
|
|
3857 // The mechanism is "half" lock-free.
|
|
3858 ParkEvent * List = FreeList ;
|
|
3859 ev->FreeNext = List ;
|
|
3860 if (Atomic::cmpxchg_ptr (ev, &FreeList, List) == List) break ;
|
|
3861 }
|
|
3862 }
|
|
3863
|
|
3864 // Override operator new and delete so we can ensure that the
|
|
3865 // least significant byte of ParkEvent addresses is 0.
|
|
3866 // Beware that excessive address alignment is undesirable
|
|
3867 // as it can result in D$ index usage imbalance as
|
|
3868 // well as bank access imbalance on Niagara-like platforms,
|
|
3869 // although Niagara's hash function should help.
|
|
3870
|
|
3871 void * ParkEvent::operator new (size_t sz) {
|
|
3872 return (void *) ((intptr_t (CHeapObj::operator new (sz + 256)) + 256) & -256) ;
|
|
3873 }
|
|
3874
|
|
3875 void ParkEvent::operator delete (void * a) {
|
|
3876 // ParkEvents are type-stable and immortal ...
|
|
3877 ShouldNotReachHere();
|
|
3878 }
|
|
3879
|
|
3880
|
|
3881 // 6399321 As a temporary measure we copied & modified the ParkEvent::
|
|
3882 // allocate() and release() code for use by Parkers. The Parker:: forms
|
|
3883 // will eventually be removed as we consolide and shift over to ParkEvents
|
|
3884 // for both builtin synchronization and JSR166 operations.
|
|
3885
|
|
3886 volatile int Parker::ListLock = 0 ;
|
|
3887 Parker * volatile Parker::FreeList = NULL ;
|
|
3888
|
|
3889 Parker * Parker::Allocate (JavaThread * t) {
|
|
3890 guarantee (t != NULL, "invariant") ;
|
|
3891 Parker * p ;
|
|
3892
|
|
3893 // Start by trying to recycle an existing but unassociated
|
|
3894 // Parker from the global free list.
|
|
3895 for (;;) {
|
|
3896 p = FreeList ;
|
|
3897 if (p == NULL) break ;
|
|
3898 // 1: Detach
|
|
3899 // Tantamount to p = Swap (&FreeList, NULL)
|
|
3900 if (Atomic::cmpxchg_ptr (NULL, &FreeList, p) != p) {
|
|
3901 continue ;
|
|
3902 }
|
|
3903
|
|
3904 // We've detached the list. The list in-hand is now
|
|
3905 // local to this thread. This thread can operate on the
|
|
3906 // list without risk of interference from other threads.
|
|
3907 // 2: Extract -- pop the 1st element from the list.
|
|
3908 Parker * List = p->FreeNext ;
|
|
3909 if (List == NULL) break ;
|
|
3910 for (;;) {
|
|
3911 // 3: Try to reattach the residual list
|
|
3912 guarantee (List != NULL, "invariant") ;
|
|
3913 Parker * Arv = (Parker *) Atomic::cmpxchg_ptr (List, &FreeList, NULL) ;
|
|
3914 if (Arv == NULL) break ;
|
|
3915
|
|
3916 // New nodes arrived. Try to detach the recent arrivals.
|
|
3917 if (Atomic::cmpxchg_ptr (NULL, &FreeList, Arv) != Arv) {
|
|
3918 continue ;
|
|
3919 }
|
|
3920 guarantee (Arv != NULL, "invariant") ;
|
|
3921 // 4: Merge Arv into List
|
|
3922 Parker * Tail = List ;
|
|
3923 while (Tail->FreeNext != NULL) Tail = Tail->FreeNext ;
|
|
3924 Tail->FreeNext = Arv ;
|
|
3925 }
|
|
3926 break ;
|
|
3927 }
|
|
3928
|
|
3929 if (p != NULL) {
|
|
3930 guarantee (p->AssociatedWith == NULL, "invariant") ;
|
|
3931 } else {
|
|
3932 // Do this the hard way -- materialize a new Parker..
|
|
3933 // In rare cases an allocating thread might detach
|
|
3934 // a long list -- installing null into FreeList --and
|
|
3935 // then stall. Another thread calling Allocate() would see
|
|
3936 // FreeList == null and then invoke the ctor. In this case we
|
|
3937 // end up with more Parkers in circulation than we need, but
|
|
3938 // the race is rare and the outcome is benign.
|
|
3939 // Ideally, the # of extant Parkers is equal to the
|
|
3940 // maximum # of threads that existed at any one time.
|
|
3941 // Because of the race mentioned above, segments of the
|
|
3942 // freelist can be transiently inaccessible. At worst
|
|
3943 // we may end up with the # of Parkers in circulation
|
|
3944 // slightly above the ideal.
|
|
3945 p = new Parker() ;
|
|
3946 }
|
|
3947 p->AssociatedWith = t ; // Associate p with t
|
|
3948 p->FreeNext = NULL ;
|
|
3949 return p ;
|
|
3950 }
|
|
3951
|
|
3952
|
|
3953 void Parker::Release (Parker * p) {
|
|
3954 if (p == NULL) return ;
|
|
3955 guarantee (p->AssociatedWith != NULL, "invariant") ;
|
|
3956 guarantee (p->FreeNext == NULL , "invariant") ;
|
|
3957 p->AssociatedWith = NULL ;
|
|
3958 for (;;) {
|
|
3959 // Push p onto FreeList
|
|
3960 Parker * List = FreeList ;
|
|
3961 p->FreeNext = List ;
|
|
3962 if (Atomic::cmpxchg_ptr (p, &FreeList, List) == List) break ;
|
|
3963 }
|
|
3964 }
|
|
3965
|
|
3966 void Threads::verify() {
|
|
3967 ALL_JAVA_THREADS(p) {
|
|
3968 p->verify();
|
|
3969 }
|
|
3970 VMThread* thread = VMThread::vm_thread();
|
|
3971 if (thread != NULL) thread->verify();
|
|
3972 }
|