annotate src/share/vm/runtime/safepoint.cpp @ 2426:1d1603768966

7010070: Update all 2010 Oracle-changed OpenJDK files to have the proper copyright dates - second pass Summary: Update the copyright to be 2010 on all changed files in OpenJDK Reviewed-by: ohair
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date Tue, 05 Apr 2011 14:12:31 -0700
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1 /*
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2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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20 * or visit www.oracle.com if you need additional information or have any
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21 * questions.
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22 *
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23 */
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24
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25 #include "precompiled.hpp"
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26 #include "classfile/systemDictionary.hpp"
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27 #include "code/codeCache.hpp"
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28 #include "code/icBuffer.hpp"
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29 #include "code/nmethod.hpp"
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30 #include "code/pcDesc.hpp"
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31 #include "code/scopeDesc.hpp"
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32 #include "gc_interface/collectedHeap.hpp"
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33 #include "interpreter/interpreter.hpp"
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34 #include "memory/resourceArea.hpp"
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35 #include "memory/universe.inline.hpp"
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36 #include "oops/oop.inline.hpp"
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37 #include "oops/symbol.hpp"
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38 #include "runtime/compilationPolicy.hpp"
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39 #include "runtime/deoptimization.hpp"
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40 #include "runtime/frame.inline.hpp"
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41 #include "runtime/interfaceSupport.hpp"
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42 #include "runtime/mutexLocker.hpp"
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43 #include "runtime/osThread.hpp"
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44 #include "runtime/safepoint.hpp"
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45 #include "runtime/signature.hpp"
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46 #include "runtime/stubCodeGenerator.hpp"
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47 #include "runtime/stubRoutines.hpp"
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48 #include "runtime/sweeper.hpp"
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49 #include "runtime/synchronizer.hpp"
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50 #include "services/runtimeService.hpp"
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51 #include "utilities/events.hpp"
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52 #ifdef TARGET_ARCH_x86
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53 # include "nativeInst_x86.hpp"
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54 # include "vmreg_x86.inline.hpp"
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55 #endif
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56 #ifdef TARGET_ARCH_sparc
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57 # include "nativeInst_sparc.hpp"
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58 # include "vmreg_sparc.inline.hpp"
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59 #endif
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60 #ifdef TARGET_ARCH_zero
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61 # include "nativeInst_zero.hpp"
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62 # include "vmreg_zero.inline.hpp"
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63 #endif
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64 #ifdef TARGET_ARCH_arm
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65 # include "nativeInst_arm.hpp"
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66 # include "vmreg_arm.inline.hpp"
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67 #endif
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68 #ifdef TARGET_ARCH_ppc
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69 # include "nativeInst_ppc.hpp"
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70 # include "vmreg_ppc.inline.hpp"
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71 #endif
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72 #ifdef TARGET_OS_FAMILY_linux
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73 # include "thread_linux.inline.hpp"
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74 #endif
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75 #ifdef TARGET_OS_FAMILY_solaris
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76 # include "thread_solaris.inline.hpp"
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77 #endif
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78 #ifdef TARGET_OS_FAMILY_windows
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79 # include "thread_windows.inline.hpp"
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80 #endif
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81 #ifndef SERIALGC
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82 #include "gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp"
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83 #include "gc_implementation/shared/concurrentGCThread.hpp"
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84 #endif
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85 #ifdef COMPILER1
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86 #include "c1/c1_globals.hpp"
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87 #endif
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88
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89 // --------------------------------------------------------------------------------------------------
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90 // Implementation of Safepoint begin/end
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91
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92 SafepointSynchronize::SynchronizeState volatile SafepointSynchronize::_state = SafepointSynchronize::_not_synchronized;
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93 volatile int SafepointSynchronize::_waiting_to_block = 0;
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94 volatile int SafepointSynchronize::_safepoint_counter = 0;
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95 long SafepointSynchronize::_end_of_last_safepoint = 0;
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96 static volatile int PageArmed = 0 ; // safepoint polling page is RO|RW vs PROT_NONE
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97 static volatile int TryingToBlock = 0 ; // proximate value -- for advisory use only
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98 static bool timeout_error_printed = false;
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99
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100 // Roll all threads forward to a safepoint and suspend them all
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101 void SafepointSynchronize::begin() {
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102
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103 Thread* myThread = Thread::current();
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104 assert(myThread->is_VM_thread(), "Only VM thread may execute a safepoint");
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105
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106 if (PrintSafepointStatistics || PrintSafepointStatisticsTimeout > 0) {
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107 _safepoint_begin_time = os::javaTimeNanos();
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108 _ts_of_current_safepoint = tty->time_stamp().seconds();
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109 }
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110
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111 #ifndef SERIALGC
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112 if (UseConcMarkSweepGC) {
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113 // In the future we should investigate whether CMS can use the
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114 // more-general mechanism below. DLD (01/05).
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115 ConcurrentMarkSweepThread::synchronize(false);
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116 } else if (UseG1GC) {
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117 ConcurrentGCThread::safepoint_synchronize();
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118 }
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119 #endif // SERIALGC
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120
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121 // By getting the Threads_lock, we assure that no threads are about to start or
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122 // exit. It is released again in SafepointSynchronize::end().
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123 Threads_lock->lock();
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124
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125 assert( _state == _not_synchronized, "trying to safepoint synchronize with wrong state");
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126
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127 int nof_threads = Threads::number_of_threads();
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128
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129 if (TraceSafepoint) {
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130 tty->print_cr("Safepoint synchronization initiated. (%d)", nof_threads);
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131 }
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132
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133 RuntimeService::record_safepoint_begin();
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134
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135 {
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136 MutexLocker mu(Safepoint_lock);
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137
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138 // Set number of threads to wait for, before we initiate the callbacks
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139 _waiting_to_block = nof_threads;
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140 TryingToBlock = 0 ;
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141 int still_running = nof_threads;
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142
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143 // Save the starting time, so that it can be compared to see if this has taken
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144 // too long to complete.
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145 jlong safepoint_limit_time;
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146 timeout_error_printed = false;
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147
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148 // PrintSafepointStatisticsTimeout can be specified separately. When
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149 // specified, PrintSafepointStatistics will be set to true in
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150 // deferred_initialize_stat method. The initialization has to be done
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151 // early enough to avoid any races. See bug 6880029 for details.
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152 if (PrintSafepointStatistics || PrintSafepointStatisticsTimeout > 0) {
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153 deferred_initialize_stat();
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154 }
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155
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156 // Begin the process of bringing the system to a safepoint.
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157 // Java threads can be in several different states and are
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158 // stopped by different mechanisms:
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159 //
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160 // 1. Running interpreted
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161 // The interpeter dispatch table is changed to force it to
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162 // check for a safepoint condition between bytecodes.
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163 // 2. Running in native code
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164 // When returning from the native code, a Java thread must check
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165 // the safepoint _state to see if we must block. If the
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166 // VM thread sees a Java thread in native, it does
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167 // not wait for this thread to block. The order of the memory
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168 // writes and reads of both the safepoint state and the Java
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169 // threads state is critical. In order to guarantee that the
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170 // memory writes are serialized with respect to each other,
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171 // the VM thread issues a memory barrier instruction
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172 // (on MP systems). In order to avoid the overhead of issuing
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173 // a memory barrier for each Java thread making native calls, each Java
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174 // thread performs a write to a single memory page after changing
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175 // the thread state. The VM thread performs a sequence of
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176 // mprotect OS calls which forces all previous writes from all
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177 // Java threads to be serialized. This is done in the
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178 // os::serialize_thread_states() call. This has proven to be
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179 // much more efficient than executing a membar instruction
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180 // on every call to native code.
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181 // 3. Running compiled Code
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182 // Compiled code reads a global (Safepoint Polling) page that
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183 // is set to fault if we are trying to get to a safepoint.
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184 // 4. Blocked
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185 // A thread which is blocked will not be allowed to return from the
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186 // block condition until the safepoint operation is complete.
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187 // 5. In VM or Transitioning between states
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188 // If a Java thread is currently running in the VM or transitioning
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189 // between states, the safepointing code will wait for the thread to
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190 // block itself when it attempts transitions to a new state.
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191 //
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192 _state = _synchronizing;
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193 OrderAccess::fence();
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194
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195 // Flush all thread states to memory
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196 if (!UseMembar) {
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197 os::serialize_thread_states();
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198 }
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199
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200 // Make interpreter safepoint aware
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201 Interpreter::notice_safepoints();
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202
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203 if (UseCompilerSafepoints && DeferPollingPageLoopCount < 0) {
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204 // Make polling safepoint aware
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205 guarantee (PageArmed == 0, "invariant") ;
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206 PageArmed = 1 ;
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207 os::make_polling_page_unreadable();
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208 }
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209
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210 // Consider using active_processor_count() ... but that call is expensive.
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211 int ncpus = os::processor_count() ;
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212
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213 #ifdef ASSERT
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214 for (JavaThread *cur = Threads::first(); cur != NULL; cur = cur->next()) {
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215 assert(cur->safepoint_state()->is_running(), "Illegal initial state");
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216 }
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217 #endif // ASSERT
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218
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219 if (SafepointTimeout)
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220 safepoint_limit_time = os::javaTimeNanos() + (jlong)SafepointTimeoutDelay * MICROUNITS;
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221
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222 // Iterate through all threads until it have been determined how to stop them all at a safepoint
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223 unsigned int iterations = 0;
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224 int steps = 0 ;
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225 while(still_running > 0) {
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226 for (JavaThread *cur = Threads::first(); cur != NULL; cur = cur->next()) {
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227 assert(!cur->is_ConcurrentGC_thread(), "A concurrent GC thread is unexpectly being suspended");
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228 ThreadSafepointState *cur_state = cur->safepoint_state();
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229 if (cur_state->is_running()) {
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230 cur_state->examine_state_of_thread();
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231 if (!cur_state->is_running()) {
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232 still_running--;
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233 // consider adjusting steps downward:
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234 // steps = 0
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235 // steps -= NNN
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236 // steps >>= 1
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237 // steps = MIN(steps, 2000-100)
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238 // if (iterations != 0) steps -= NNN
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239 }
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240 if (TraceSafepoint && Verbose) cur_state->print();
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241 }
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242 }
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243
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244 if (PrintSafepointStatistics && iterations == 0) {
0
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245 begin_statistics(nof_threads, still_running);
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246 }
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247
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248 if (still_running > 0) {
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249 // Check for if it takes to long
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250 if (SafepointTimeout && safepoint_limit_time < os::javaTimeNanos()) {
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251 print_safepoint_timeout(_spinning_timeout);
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252 }
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253
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254 // Spin to avoid context switching.
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255 // There's a tension between allowing the mutators to run (and rendezvous)
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256 // vs spinning. As the VM thread spins, wasting cycles, it consumes CPU that
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257 // a mutator might otherwise use profitably to reach a safepoint. Excessive
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258 // spinning by the VM thread on a saturated system can increase rendezvous latency.
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259 // Blocking or yielding incur their own penalties in the form of context switching
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260 // and the resultant loss of $ residency.
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261 //
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262 // Further complicating matters is that yield() does not work as naively expected
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263 // on many platforms -- yield() does not guarantee that any other ready threads
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264 // will run. As such we revert yield_all() after some number of iterations.
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265 // Yield_all() is implemented as a short unconditional sleep on some platforms.
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266 // Typical operating systems round a "short" sleep period up to 10 msecs, so sleeping
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267 // can actually increase the time it takes the VM thread to detect that a system-wide
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268 // stop-the-world safepoint has been reached. In a pathological scenario such as that
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269 // described in CR6415670 the VMthread may sleep just before the mutator(s) become safe.
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270 // In that case the mutators will be stalled waiting for the safepoint to complete and the
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271 // the VMthread will be sleeping, waiting for the mutators to rendezvous. The VMthread
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272 // will eventually wake up and detect that all mutators are safe, at which point
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273 // we'll again make progress.
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274 //
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275 // Beware too that that the VMThread typically runs at elevated priority.
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276 // Its default priority is higher than the default mutator priority.
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277 // Obviously, this complicates spinning.
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278 //
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279 // Note too that on Windows XP SwitchThreadTo() has quite different behavior than Sleep(0).
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280 // Sleep(0) will _not yield to lower priority threads, while SwitchThreadTo() will.
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281 //
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282 // See the comments in synchronizer.cpp for additional remarks on spinning.
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283 //
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284 // In the future we might:
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285 // 1. Modify the safepoint scheme to avoid potentally unbounded spinning.
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286 // This is tricky as the path used by a thread exiting the JVM (say on
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287 // on JNI call-out) simply stores into its state field. The burden
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288 // is placed on the VM thread, which must poll (spin).
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289 // 2. Find something useful to do while spinning. If the safepoint is GC-related
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290 // we might aggressively scan the stacks of threads that are already safe.
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291 // 3. Use Solaris schedctl to examine the state of the still-running mutators.
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292 // If all the mutators are ONPROC there's no reason to sleep or yield.
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293 // 4. YieldTo() any still-running mutators that are ready but OFFPROC.
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294 // 5. Check system saturation. If the system is not fully saturated then
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295 // simply spin and avoid sleep/yield.
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296 // 6. As still-running mutators rendezvous they could unpark the sleeping
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297 // VMthread. This works well for still-running mutators that become
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298 // safe. The VMthread must still poll for mutators that call-out.
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299 // 7. Drive the policy on time-since-begin instead of iterations.
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300 // 8. Consider making the spin duration a function of the # of CPUs:
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301 // Spin = (((ncpus-1) * M) + K) + F(still_running)
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302 // Alternately, instead of counting iterations of the outer loop
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303 // we could count the # of threads visited in the inner loop, above.
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304 // 9. On windows consider using the return value from SwitchThreadTo()
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305 // to drive subsequent spin/SwitchThreadTo()/Sleep(N) decisions.
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306
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307 if (UseCompilerSafepoints && int(iterations) == DeferPollingPageLoopCount) {
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308 guarantee (PageArmed == 0, "invariant") ;
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309 PageArmed = 1 ;
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310 os::make_polling_page_unreadable();
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311 }
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312
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313 // Instead of (ncpus > 1) consider either (still_running < (ncpus + EPSILON)) or
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314 // ((still_running + _waiting_to_block - TryingToBlock)) < ncpus)
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315 ++steps ;
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316 if (ncpus > 1 && steps < SafepointSpinBeforeYield) {
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317 SpinPause() ; // MP-Polite spin
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318 } else
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319 if (steps < DeferThrSuspendLoopCount) {
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320 os::NakedYield() ;
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321 } else {
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322 os::yield_all(steps) ;
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323 // Alternately, the VM thread could transiently depress its scheduling priority or
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324 // transiently increase the priority of the tardy mutator(s).
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325 }
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326
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327 iterations ++ ;
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328 }
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329 assert(iterations < (uint)max_jint, "We have been iterating in the safepoint loop too long");
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330 }
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331 assert(still_running == 0, "sanity check");
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332
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333 if (PrintSafepointStatistics) {
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334 update_statistics_on_spin_end();
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335 }
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336
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337 // wait until all threads are stopped
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338 while (_waiting_to_block > 0) {
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339 if (TraceSafepoint) tty->print_cr("Waiting for %d thread(s) to block", _waiting_to_block);
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340 if (!SafepointTimeout || timeout_error_printed) {
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341 Safepoint_lock->wait(true); // true, means with no safepoint checks
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342 } else {
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343 // Compute remaining time
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344 jlong remaining_time = safepoint_limit_time - os::javaTimeNanos();
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345
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346 // If there is no remaining time, then there is an error
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347 if (remaining_time < 0 || Safepoint_lock->wait(true, remaining_time / MICROUNITS)) {
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348 print_safepoint_timeout(_blocking_timeout);
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349 }
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350 }
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351 }
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352 assert(_waiting_to_block == 0, "sanity check");
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353
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354 #ifndef PRODUCT
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355 if (SafepointTimeout) {
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356 jlong current_time = os::javaTimeNanos();
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357 if (safepoint_limit_time < current_time) {
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358 tty->print_cr("# SafepointSynchronize: Finished after "
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359 INT64_FORMAT_W(6) " ms",
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360 ((current_time - safepoint_limit_time) / MICROUNITS +
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361 SafepointTimeoutDelay));
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362 }
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363 }
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364 #endif
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365
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366 assert((_safepoint_counter & 0x1) == 0, "must be even");
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367 assert(Threads_lock->owned_by_self(), "must hold Threads_lock");
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368 _safepoint_counter ++;
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369
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370 // Record state
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371 _state = _synchronized;
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372
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373 OrderAccess::fence();
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374
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375 if (TraceSafepoint) {
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376 VM_Operation *op = VMThread::vm_operation();
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377 tty->print_cr("Entering safepoint region: %s", (op != NULL) ? op->name() : "no vm operation");
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378 }
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379
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380 RuntimeService::record_safepoint_synchronized();
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381 if (PrintSafepointStatistics) {
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382 update_statistics_on_sync_end(os::javaTimeNanos());
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383 }
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384
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385 // Call stuff that needs to be run when a safepoint is just about to be completed
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386 do_cleanup_tasks();
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387
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388 if (PrintSafepointStatistics) {
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389 // Record how much time spend on the above cleanup tasks
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390 update_statistics_on_cleanup_end(os::javaTimeNanos());
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391 }
0
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392 }
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393 }
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394
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395 // Wake up all threads, so they are ready to resume execution after the safepoint
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396 // operation has been carried out
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397 void SafepointSynchronize::end() {
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398
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399 assert(Threads_lock->owned_by_self(), "must hold Threads_lock");
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400 assert((_safepoint_counter & 0x1) == 1, "must be odd");
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401 _safepoint_counter ++;
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duke
parents:
diff changeset
402 // memory fence isn't required here since an odd _safepoint_counter
a61af66fc99e Initial load
duke
parents:
diff changeset
403 // value can do no harm and a fence is issued below anyway.
a61af66fc99e Initial load
duke
parents:
diff changeset
404
a61af66fc99e Initial load
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parents:
diff changeset
405 DEBUG_ONLY(Thread* myThread = Thread::current();)
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duke
parents:
diff changeset
406 assert(myThread->is_VM_thread(), "Only VM thread can execute a safepoint");
a61af66fc99e Initial load
duke
parents:
diff changeset
407
a61af66fc99e Initial load
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parents:
diff changeset
408 if (PrintSafepointStatistics) {
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duke
parents:
diff changeset
409 end_statistics(os::javaTimeNanos());
a61af66fc99e Initial load
duke
parents:
diff changeset
410 }
a61af66fc99e Initial load
duke
parents:
diff changeset
411
a61af66fc99e Initial load
duke
parents:
diff changeset
412 #ifdef ASSERT
a61af66fc99e Initial load
duke
parents:
diff changeset
413 // A pending_exception cannot be installed during a safepoint. The threads
a61af66fc99e Initial load
duke
parents:
diff changeset
414 // may install an async exception after they come back from a safepoint into
a61af66fc99e Initial load
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parents:
diff changeset
415 // pending_exception after they unblock. But that should happen later.
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parents:
diff changeset
416 for(JavaThread *cur = Threads::first(); cur; cur = cur->next()) {
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parents:
diff changeset
417 assert (!(cur->has_pending_exception() &&
a61af66fc99e Initial load
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parents:
diff changeset
418 cur->safepoint_state()->is_at_poll_safepoint()),
a61af66fc99e Initial load
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parents:
diff changeset
419 "safepoint installed a pending exception");
a61af66fc99e Initial load
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parents:
diff changeset
420 }
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parents:
diff changeset
421 #endif // ASSERT
a61af66fc99e Initial load
duke
parents:
diff changeset
422
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parents:
diff changeset
423 if (PageArmed) {
a61af66fc99e Initial load
duke
parents:
diff changeset
424 // Make polling safepoint aware
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parents:
diff changeset
425 os::make_polling_page_readable();
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duke
parents:
diff changeset
426 PageArmed = 0 ;
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parents:
diff changeset
427 }
a61af66fc99e Initial load
duke
parents:
diff changeset
428
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duke
parents:
diff changeset
429 // Remove safepoint check from interpreter
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parents:
diff changeset
430 Interpreter::ignore_safepoints();
a61af66fc99e Initial load
duke
parents:
diff changeset
431
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duke
parents:
diff changeset
432 {
a61af66fc99e Initial load
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parents:
diff changeset
433 MutexLocker mu(Safepoint_lock);
a61af66fc99e Initial load
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parents:
diff changeset
434
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parents:
diff changeset
435 assert(_state == _synchronized, "must be synchronized before ending safepoint synchronization");
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duke
parents:
diff changeset
436
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duke
parents:
diff changeset
437 // Set to not synchronized, so the threads will not go into the signal_thread_blocked method
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duke
parents:
diff changeset
438 // when they get restarted.
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parents:
diff changeset
439 _state = _not_synchronized;
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parents:
diff changeset
440 OrderAccess::fence();
a61af66fc99e Initial load
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parents:
diff changeset
441
a61af66fc99e Initial load
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parents:
diff changeset
442 if (TraceSafepoint) {
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parents:
diff changeset
443 tty->print_cr("Leaving safepoint region");
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parents:
diff changeset
444 }
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parents:
diff changeset
445
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parents:
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446 // Start suspended threads
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parents:
diff changeset
447 for(JavaThread *current = Threads::first(); current; current = current->next()) {
605
98cb887364d3 6810672: Comment typos
twisti
parents: 513
diff changeset
448 // A problem occurring on Solaris is when attempting to restart threads
0
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parents:
diff changeset
449 // the first #cpus - 1 go well, but then the VMThread is preempted when we get
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parents:
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450 // to the next one (since it has been running the longest). We then have
a61af66fc99e Initial load
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parents:
diff changeset
451 // to wait for a cpu to become available before we can continue restarting
a61af66fc99e Initial load
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parents:
diff changeset
452 // threads.
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duke
parents:
diff changeset
453 // FIXME: This causes the performance of the VM to degrade when active and with
a61af66fc99e Initial load
duke
parents:
diff changeset
454 // large numbers of threads. Apparently this is due to the synchronous nature
a61af66fc99e Initial load
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parents:
diff changeset
455 // of suspending threads.
a61af66fc99e Initial load
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parents:
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456 //
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duke
parents:
diff changeset
457 // TODO-FIXME: the comments above are vestigial and no longer apply.
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parents:
diff changeset
458 // Furthermore, using solaris' schedctl in this particular context confers no benefit
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duke
parents:
diff changeset
459 if (VMThreadHintNoPreempt) {
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parents:
diff changeset
460 os::hint_no_preempt();
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parents:
diff changeset
461 }
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parents:
diff changeset
462 ThreadSafepointState* cur_state = current->safepoint_state();
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parents:
diff changeset
463 assert(cur_state->type() != ThreadSafepointState::_running, "Thread not suspended at safepoint");
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parents:
diff changeset
464 cur_state->restart();
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parents:
diff changeset
465 assert(cur_state->is_running(), "safepoint state has not been reset");
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parents:
diff changeset
466 }
a61af66fc99e Initial load
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parents:
diff changeset
467
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parents:
diff changeset
468 RuntimeService::record_safepoint_end();
a61af66fc99e Initial load
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parents:
diff changeset
469
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parents:
diff changeset
470 // Release threads lock, so threads can be created/destroyed again. It will also starts all threads
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parents:
diff changeset
471 // blocked in signal_thread_blocked
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parents:
diff changeset
472 Threads_lock->unlock();
a61af66fc99e Initial load
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parents:
diff changeset
473
a61af66fc99e Initial load
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parents:
diff changeset
474 }
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duke
parents:
diff changeset
475 #ifndef SERIALGC
a61af66fc99e Initial load
duke
parents:
diff changeset
476 // If there are any concurrent GC threads resume them.
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duke
parents:
diff changeset
477 if (UseConcMarkSweepGC) {
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duke
parents:
diff changeset
478 ConcurrentMarkSweepThread::desynchronize(false);
845
df6caf649ff7 6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents: 628
diff changeset
479 } else if (UseG1GC) {
0
a61af66fc99e Initial load
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parents:
diff changeset
480 ConcurrentGCThread::safepoint_desynchronize();
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duke
parents:
diff changeset
481 }
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duke
parents:
diff changeset
482 #endif // SERIALGC
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
483 // record this time so VMThread can keep track how much time has elasped
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
484 // since last safepoint.
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
485 _end_of_last_safepoint = os::javaTimeMillis();
0
a61af66fc99e Initial load
duke
parents:
diff changeset
486 }
a61af66fc99e Initial load
duke
parents:
diff changeset
487
a61af66fc99e Initial load
duke
parents:
diff changeset
488 bool SafepointSynchronize::is_cleanup_needed() {
a61af66fc99e Initial load
duke
parents:
diff changeset
489 // Need a safepoint if some inline cache buffers is non-empty
a61af66fc99e Initial load
duke
parents:
diff changeset
490 if (!InlineCacheBuffer::is_empty()) return true;
a61af66fc99e Initial load
duke
parents:
diff changeset
491 return false;
a61af66fc99e Initial load
duke
parents:
diff changeset
492 }
a61af66fc99e Initial load
duke
parents:
diff changeset
493
a61af66fc99e Initial load
duke
parents:
diff changeset
494
a61af66fc99e Initial load
duke
parents:
diff changeset
495
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duke
parents:
diff changeset
496 // Various cleaning tasks that should be done periodically at safepoints
a61af66fc99e Initial load
duke
parents:
diff changeset
497 void SafepointSynchronize::do_cleanup_tasks() {
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
498 {
1321
0f6600cee529 6934758: Expose the break down of clean up task time during safepoint.
xlu
parents: 1291
diff changeset
499 TraceTime t1("deflating idle monitors", TraceSafepointCleanupTime);
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
500 ObjectSynchronizer::deflate_idle_monitors();
0
a61af66fc99e Initial load
duke
parents:
diff changeset
501 }
a61af66fc99e Initial load
duke
parents:
diff changeset
502
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
503 {
1321
0f6600cee529 6934758: Expose the break down of clean up task time during safepoint.
xlu
parents: 1291
diff changeset
504 TraceTime t2("updating inline caches", TraceSafepointCleanupTime);
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
505 InlineCacheBuffer::update_inline_caches();
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
506 }
1783
d5d065957597 6953144: Tiered compilation
iveresov
parents: 1727
diff changeset
507 {
d5d065957597 6953144: Tiered compilation
iveresov
parents: 1727
diff changeset
508 TraceTime t3("compilation policy safepoint handler", TraceSafepointCleanupTime);
d5d065957597 6953144: Tiered compilation
iveresov
parents: 1727
diff changeset
509 CompilationPolicy::policy()->do_safepoint_work();
0
a61af66fc99e Initial load
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parents:
diff changeset
510 }
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
511
1321
0f6600cee529 6934758: Expose the break down of clean up task time during safepoint.
xlu
parents: 1291
diff changeset
512 TraceTime t4("sweeping nmethods", TraceSafepointCleanupTime);
1538
bfe29ec02863 6950075: nmethod sweeper should operate concurrently
never
parents: 1490
diff changeset
513 NMethodSweeper::scan_stacks();
0
a61af66fc99e Initial load
duke
parents:
diff changeset
514 }
a61af66fc99e Initial load
duke
parents:
diff changeset
515
a61af66fc99e Initial load
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parents:
diff changeset
516
a61af66fc99e Initial load
duke
parents:
diff changeset
517 bool SafepointSynchronize::safepoint_safe(JavaThread *thread, JavaThreadState state) {
a61af66fc99e Initial load
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parents:
diff changeset
518 switch(state) {
a61af66fc99e Initial load
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parents:
diff changeset
519 case _thread_in_native:
a61af66fc99e Initial load
duke
parents:
diff changeset
520 // native threads are safe if they have no java stack or have walkable stack
a61af66fc99e Initial load
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parents:
diff changeset
521 return !thread->has_last_Java_frame() || thread->frame_anchor()->walkable();
a61af66fc99e Initial load
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parents:
diff changeset
522
a61af66fc99e Initial load
duke
parents:
diff changeset
523 // blocked threads should have already have walkable stack
a61af66fc99e Initial load
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parents:
diff changeset
524 case _thread_blocked:
a61af66fc99e Initial load
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parents:
diff changeset
525 assert(!thread->has_last_Java_frame() || thread->frame_anchor()->walkable(), "blocked and not walkable");
a61af66fc99e Initial load
duke
parents:
diff changeset
526 return true;
a61af66fc99e Initial load
duke
parents:
diff changeset
527
a61af66fc99e Initial load
duke
parents:
diff changeset
528 default:
a61af66fc99e Initial load
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parents:
diff changeset
529 return false;
a61af66fc99e Initial load
duke
parents:
diff changeset
530 }
a61af66fc99e Initial load
duke
parents:
diff changeset
531 }
a61af66fc99e Initial load
duke
parents:
diff changeset
532
a61af66fc99e Initial load
duke
parents:
diff changeset
533
a61af66fc99e Initial load
duke
parents:
diff changeset
534 // -------------------------------------------------------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
535 // Implementation of Safepoint callback point
a61af66fc99e Initial load
duke
parents:
diff changeset
536
a61af66fc99e Initial load
duke
parents:
diff changeset
537 void SafepointSynchronize::block(JavaThread *thread) {
a61af66fc99e Initial load
duke
parents:
diff changeset
538 assert(thread != NULL, "thread must be set");
a61af66fc99e Initial load
duke
parents:
diff changeset
539 assert(thread->is_Java_thread(), "not a Java thread");
a61af66fc99e Initial load
duke
parents:
diff changeset
540
a61af66fc99e Initial load
duke
parents:
diff changeset
541 // Threads shouldn't block if they are in the middle of printing, but...
a61af66fc99e Initial load
duke
parents:
diff changeset
542 ttyLocker::break_tty_lock_for_safepoint(os::current_thread_id());
a61af66fc99e Initial load
duke
parents:
diff changeset
543
a61af66fc99e Initial load
duke
parents:
diff changeset
544 // Only bail from the block() call if the thread is gone from the
a61af66fc99e Initial load
duke
parents:
diff changeset
545 // thread list; starting to exit should still block.
a61af66fc99e Initial load
duke
parents:
diff changeset
546 if (thread->is_terminated()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
547 // block current thread if we come here from native code when VM is gone
a61af66fc99e Initial load
duke
parents:
diff changeset
548 thread->block_if_vm_exited();
a61af66fc99e Initial load
duke
parents:
diff changeset
549
a61af66fc99e Initial load
duke
parents:
diff changeset
550 // otherwise do nothing
a61af66fc99e Initial load
duke
parents:
diff changeset
551 return;
a61af66fc99e Initial load
duke
parents:
diff changeset
552 }
a61af66fc99e Initial load
duke
parents:
diff changeset
553
a61af66fc99e Initial load
duke
parents:
diff changeset
554 JavaThreadState state = thread->thread_state();
a61af66fc99e Initial load
duke
parents:
diff changeset
555 thread->frame_anchor()->make_walkable(thread);
a61af66fc99e Initial load
duke
parents:
diff changeset
556
a61af66fc99e Initial load
duke
parents:
diff changeset
557 // Check that we have a valid thread_state at this point
a61af66fc99e Initial load
duke
parents:
diff changeset
558 switch(state) {
a61af66fc99e Initial load
duke
parents:
diff changeset
559 case _thread_in_vm_trans:
a61af66fc99e Initial load
duke
parents:
diff changeset
560 case _thread_in_Java: // From compiled code
a61af66fc99e Initial load
duke
parents:
diff changeset
561
a61af66fc99e Initial load
duke
parents:
diff changeset
562 // We are highly likely to block on the Safepoint_lock. In order to avoid blocking in this case,
a61af66fc99e Initial load
duke
parents:
diff changeset
563 // we pretend we are still in the VM.
a61af66fc99e Initial load
duke
parents:
diff changeset
564 thread->set_thread_state(_thread_in_vm);
a61af66fc99e Initial load
duke
parents:
diff changeset
565
a61af66fc99e Initial load
duke
parents:
diff changeset
566 if (is_synchronizing()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
567 Atomic::inc (&TryingToBlock) ;
a61af66fc99e Initial load
duke
parents:
diff changeset
568 }
a61af66fc99e Initial load
duke
parents:
diff changeset
569
a61af66fc99e Initial load
duke
parents:
diff changeset
570 // We will always be holding the Safepoint_lock when we are examine the state
a61af66fc99e Initial load
duke
parents:
diff changeset
571 // of a thread. Hence, the instructions between the Safepoint_lock->lock() and
a61af66fc99e Initial load
duke
parents:
diff changeset
572 // Safepoint_lock->unlock() are happening atomic with regards to the safepoint code
a61af66fc99e Initial load
duke
parents:
diff changeset
573 Safepoint_lock->lock_without_safepoint_check();
a61af66fc99e Initial load
duke
parents:
diff changeset
574 if (is_synchronizing()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
575 // Decrement the number of threads to wait for and signal vm thread
a61af66fc99e Initial load
duke
parents:
diff changeset
576 assert(_waiting_to_block > 0, "sanity check");
a61af66fc99e Initial load
duke
parents:
diff changeset
577 _waiting_to_block--;
a61af66fc99e Initial load
duke
parents:
diff changeset
578 thread->safepoint_state()->set_has_called_back(true);
a61af66fc99e Initial load
duke
parents:
diff changeset
579
a61af66fc99e Initial load
duke
parents:
diff changeset
580 // Consider (_waiting_to_block < 2) to pipeline the wakeup of the VM thread
a61af66fc99e Initial load
duke
parents:
diff changeset
581 if (_waiting_to_block == 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
582 Safepoint_lock->notify_all();
a61af66fc99e Initial load
duke
parents:
diff changeset
583 }
a61af66fc99e Initial load
duke
parents:
diff changeset
584 }
a61af66fc99e Initial load
duke
parents:
diff changeset
585
a61af66fc99e Initial load
duke
parents:
diff changeset
586 // We transition the thread to state _thread_blocked here, but
a61af66fc99e Initial load
duke
parents:
diff changeset
587 // we can't do our usual check for external suspension and then
a61af66fc99e Initial load
duke
parents:
diff changeset
588 // self-suspend after the lock_without_safepoint_check() call
a61af66fc99e Initial load
duke
parents:
diff changeset
589 // below because we are often called during transitions while
a61af66fc99e Initial load
duke
parents:
diff changeset
590 // we hold different locks. That would leave us suspended while
a61af66fc99e Initial load
duke
parents:
diff changeset
591 // holding a resource which results in deadlocks.
a61af66fc99e Initial load
duke
parents:
diff changeset
592 thread->set_thread_state(_thread_blocked);
a61af66fc99e Initial load
duke
parents:
diff changeset
593 Safepoint_lock->unlock();
a61af66fc99e Initial load
duke
parents:
diff changeset
594
a61af66fc99e Initial load
duke
parents:
diff changeset
595 // We now try to acquire the threads lock. Since this lock is hold by the VM thread during
a61af66fc99e Initial load
duke
parents:
diff changeset
596 // the entire safepoint, the threads will all line up here during the safepoint.
a61af66fc99e Initial load
duke
parents:
diff changeset
597 Threads_lock->lock_without_safepoint_check();
a61af66fc99e Initial load
duke
parents:
diff changeset
598 // restore original state. This is important if the thread comes from compiled code, so it
a61af66fc99e Initial load
duke
parents:
diff changeset
599 // will continue to execute with the _thread_in_Java state.
a61af66fc99e Initial load
duke
parents:
diff changeset
600 thread->set_thread_state(state);
a61af66fc99e Initial load
duke
parents:
diff changeset
601 Threads_lock->unlock();
a61af66fc99e Initial load
duke
parents:
diff changeset
602 break;
a61af66fc99e Initial load
duke
parents:
diff changeset
603
a61af66fc99e Initial load
duke
parents:
diff changeset
604 case _thread_in_native_trans:
a61af66fc99e Initial load
duke
parents:
diff changeset
605 case _thread_blocked_trans:
a61af66fc99e Initial load
duke
parents:
diff changeset
606 case _thread_new_trans:
a61af66fc99e Initial load
duke
parents:
diff changeset
607 if (thread->safepoint_state()->type() == ThreadSafepointState::_call_back) {
a61af66fc99e Initial load
duke
parents:
diff changeset
608 thread->print_thread_state();
a61af66fc99e Initial load
duke
parents:
diff changeset
609 fatal("Deadlock in safepoint code. "
a61af66fc99e Initial load
duke
parents:
diff changeset
610 "Should have called back to the VM before blocking.");
a61af66fc99e Initial load
duke
parents:
diff changeset
611 }
a61af66fc99e Initial load
duke
parents:
diff changeset
612
a61af66fc99e Initial load
duke
parents:
diff changeset
613 // We transition the thread to state _thread_blocked here, but
a61af66fc99e Initial load
duke
parents:
diff changeset
614 // we can't do our usual check for external suspension and then
a61af66fc99e Initial load
duke
parents:
diff changeset
615 // self-suspend after the lock_without_safepoint_check() call
a61af66fc99e Initial load
duke
parents:
diff changeset
616 // below because we are often called during transitions while
a61af66fc99e Initial load
duke
parents:
diff changeset
617 // we hold different locks. That would leave us suspended while
a61af66fc99e Initial load
duke
parents:
diff changeset
618 // holding a resource which results in deadlocks.
a61af66fc99e Initial load
duke
parents:
diff changeset
619 thread->set_thread_state(_thread_blocked);
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parents:
diff changeset
620
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parents:
diff changeset
621 // It is not safe to suspend a thread if we discover it is in _thread_in_native_trans. Hence,
a61af66fc99e Initial load
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parents:
diff changeset
622 // the safepoint code might still be waiting for it to block. We need to change the state here,
a61af66fc99e Initial load
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parents:
diff changeset
623 // so it can see that it is at a safepoint.
a61af66fc99e Initial load
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parents:
diff changeset
624
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parents:
diff changeset
625 // Block until the safepoint operation is completed.
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parents:
diff changeset
626 Threads_lock->lock_without_safepoint_check();
a61af66fc99e Initial load
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parents:
diff changeset
627
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parents:
diff changeset
628 // Restore state
a61af66fc99e Initial load
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parents:
diff changeset
629 thread->set_thread_state(state);
a61af66fc99e Initial load
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parents:
diff changeset
630
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parents:
diff changeset
631 Threads_lock->unlock();
a61af66fc99e Initial load
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parents:
diff changeset
632 break;
a61af66fc99e Initial load
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parents:
diff changeset
633
a61af66fc99e Initial load
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parents:
diff changeset
634 default:
1490
f03d0a26bf83 6888954: argument formatting for assert() and friends
jcoomes
parents: 1321
diff changeset
635 fatal(err_msg("Illegal threadstate encountered: %d", state));
0
a61af66fc99e Initial load
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parents:
diff changeset
636 }
a61af66fc99e Initial load
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parents:
diff changeset
637
a61af66fc99e Initial load
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parents:
diff changeset
638 // Check for pending. async. exceptions or suspends - except if the
a61af66fc99e Initial load
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parents:
diff changeset
639 // thread was blocked inside the VM. has_special_runtime_exit_condition()
a61af66fc99e Initial load
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parents:
diff changeset
640 // is called last since it grabs a lock and we only want to do that when
a61af66fc99e Initial load
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parents:
diff changeset
641 // we must.
a61af66fc99e Initial load
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parents:
diff changeset
642 //
a61af66fc99e Initial load
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parents:
diff changeset
643 // Note: we never deliver an async exception at a polling point as the
a61af66fc99e Initial load
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parents:
diff changeset
644 // compiler may not have an exception handler for it. The polling
a61af66fc99e Initial load
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parents:
diff changeset
645 // code will notice the async and deoptimize and the exception will
a61af66fc99e Initial load
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parents:
diff changeset
646 // be delivered. (Polling at a return point is ok though). Sure is
a61af66fc99e Initial load
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parents:
diff changeset
647 // a lot of bother for a deprecated feature...
a61af66fc99e Initial load
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parents:
diff changeset
648 //
a61af66fc99e Initial load
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parents:
diff changeset
649 // We don't deliver an async exception if the thread state is
a61af66fc99e Initial load
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parents:
diff changeset
650 // _thread_in_native_trans so JNI functions won't be called with
a61af66fc99e Initial load
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parents:
diff changeset
651 // a surprising pending exception. If the thread state is going back to java,
a61af66fc99e Initial load
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parents:
diff changeset
652 // async exception is checked in check_special_condition_for_native_trans().
a61af66fc99e Initial load
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parents:
diff changeset
653
a61af66fc99e Initial load
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parents:
diff changeset
654 if (state != _thread_blocked_trans &&
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parents:
diff changeset
655 state != _thread_in_vm_trans &&
a61af66fc99e Initial load
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parents:
diff changeset
656 thread->has_special_runtime_exit_condition()) {
a61af66fc99e Initial load
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parents:
diff changeset
657 thread->handle_special_runtime_exit_condition(
a61af66fc99e Initial load
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parents:
diff changeset
658 !thread->is_at_poll_safepoint() && (state != _thread_in_native_trans));
a61af66fc99e Initial load
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parents:
diff changeset
659 }
a61af66fc99e Initial load
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parents:
diff changeset
660 }
a61af66fc99e Initial load
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parents:
diff changeset
661
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parents:
diff changeset
662 // ------------------------------------------------------------------------------------------------------
a61af66fc99e Initial load
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parents:
diff changeset
663 // Exception handlers
a61af66fc99e Initial load
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parents:
diff changeset
664
a61af66fc99e Initial load
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parents:
diff changeset
665 #ifndef PRODUCT
a61af66fc99e Initial load
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parents:
diff changeset
666 #ifdef _LP64
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parents:
diff changeset
667 #define PTR_PAD ""
a61af66fc99e Initial load
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parents:
diff changeset
668 #else
a61af66fc99e Initial load
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parents:
diff changeset
669 #define PTR_PAD " "
a61af66fc99e Initial load
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parents:
diff changeset
670 #endif
a61af66fc99e Initial load
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parents:
diff changeset
671
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parents:
diff changeset
672 static void print_ptrs(intptr_t oldptr, intptr_t newptr, bool wasoop) {
a61af66fc99e Initial load
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parents:
diff changeset
673 bool is_oop = newptr ? ((oop)newptr)->is_oop() : false;
a61af66fc99e Initial load
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parents:
diff changeset
674 tty->print_cr(PTR_FORMAT PTR_PAD " %s %c " PTR_FORMAT PTR_PAD " %s %s",
a61af66fc99e Initial load
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parents:
diff changeset
675 oldptr, wasoop?"oop":" ", oldptr == newptr ? ' ' : '!',
a61af66fc99e Initial load
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parents:
diff changeset
676 newptr, is_oop?"oop":" ", (wasoop && !is_oop) ? "STALE" : ((wasoop==false&&is_oop==false&&oldptr !=newptr)?"STOMP":" "));
a61af66fc99e Initial load
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parents:
diff changeset
677 }
a61af66fc99e Initial load
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parents:
diff changeset
678
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parents:
diff changeset
679 static void print_longs(jlong oldptr, jlong newptr, bool wasoop) {
a61af66fc99e Initial load
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parents:
diff changeset
680 bool is_oop = newptr ? ((oop)(intptr_t)newptr)->is_oop() : false;
a61af66fc99e Initial load
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parents:
diff changeset
681 tty->print_cr(PTR64_FORMAT " %s %c " PTR64_FORMAT " %s %s",
a61af66fc99e Initial load
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parents:
diff changeset
682 oldptr, wasoop?"oop":" ", oldptr == newptr ? ' ' : '!',
a61af66fc99e Initial load
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parents:
diff changeset
683 newptr, is_oop?"oop":" ", (wasoop && !is_oop) ? "STALE" : ((wasoop==false&&is_oop==false&&oldptr !=newptr)?"STOMP":" "));
a61af66fc99e Initial load
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parents:
diff changeset
684 }
a61af66fc99e Initial load
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parents:
diff changeset
685
a61af66fc99e Initial load
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parents:
diff changeset
686 #ifdef SPARC
a61af66fc99e Initial load
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parents:
diff changeset
687 static void print_me(intptr_t *new_sp, intptr_t *old_sp, bool *was_oops) {
a61af66fc99e Initial load
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parents:
diff changeset
688 #ifdef _LP64
a61af66fc99e Initial load
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parents:
diff changeset
689 tty->print_cr("--------+------address-----+------before-----------+-------after----------+");
a61af66fc99e Initial load
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parents:
diff changeset
690 const int incr = 1; // Increment to skip a long, in units of intptr_t
a61af66fc99e Initial load
duke
parents:
diff changeset
691 #else
a61af66fc99e Initial load
duke
parents:
diff changeset
692 tty->print_cr("--------+--address-+------before-----------+-------after----------+");
a61af66fc99e Initial load
duke
parents:
diff changeset
693 const int incr = 2; // Increment to skip a long, in units of intptr_t
a61af66fc99e Initial load
duke
parents:
diff changeset
694 #endif
a61af66fc99e Initial load
duke
parents:
diff changeset
695 tty->print_cr("---SP---|");
a61af66fc99e Initial load
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parents:
diff changeset
696 for( int i=0; i<16; i++ ) {
a61af66fc99e Initial load
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parents:
diff changeset
697 tty->print("blob %c%d |"PTR_FORMAT" ","LO"[i>>3],i&7,new_sp); print_ptrs(*old_sp++,*new_sp++,*was_oops++); }
a61af66fc99e Initial load
duke
parents:
diff changeset
698 tty->print_cr("--------|");
a61af66fc99e Initial load
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parents:
diff changeset
699 for( int i1=0; i1<frame::memory_parameter_word_sp_offset-16; i1++ ) {
a61af66fc99e Initial load
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parents:
diff changeset
700 tty->print("argv pad|"PTR_FORMAT" ",new_sp); print_ptrs(*old_sp++,*new_sp++,*was_oops++); }
a61af66fc99e Initial load
duke
parents:
diff changeset
701 tty->print(" pad|"PTR_FORMAT" ",new_sp); print_ptrs(*old_sp++,*new_sp++,*was_oops++);
a61af66fc99e Initial load
duke
parents:
diff changeset
702 tty->print_cr("--------|");
a61af66fc99e Initial load
duke
parents:
diff changeset
703 tty->print(" G1 |"PTR_FORMAT" ",new_sp); print_longs(*(jlong*)old_sp,*(jlong*)new_sp,was_oops[incr-1]); old_sp += incr; new_sp += incr; was_oops += incr;
a61af66fc99e Initial load
duke
parents:
diff changeset
704 tty->print(" G3 |"PTR_FORMAT" ",new_sp); print_longs(*(jlong*)old_sp,*(jlong*)new_sp,was_oops[incr-1]); old_sp += incr; new_sp += incr; was_oops += incr;
a61af66fc99e Initial load
duke
parents:
diff changeset
705 tty->print(" G4 |"PTR_FORMAT" ",new_sp); print_longs(*(jlong*)old_sp,*(jlong*)new_sp,was_oops[incr-1]); old_sp += incr; new_sp += incr; was_oops += incr;
a61af66fc99e Initial load
duke
parents:
diff changeset
706 tty->print(" G5 |"PTR_FORMAT" ",new_sp); print_longs(*(jlong*)old_sp,*(jlong*)new_sp,was_oops[incr-1]); old_sp += incr; new_sp += incr; was_oops += incr;
a61af66fc99e Initial load
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parents:
diff changeset
707 tty->print_cr(" FSR |"PTR_FORMAT" "PTR64_FORMAT" "PTR64_FORMAT,new_sp,*(jlong*)old_sp,*(jlong*)new_sp);
a61af66fc99e Initial load
duke
parents:
diff changeset
708 old_sp += incr; new_sp += incr; was_oops += incr;
a61af66fc99e Initial load
duke
parents:
diff changeset
709 // Skip the floats
a61af66fc99e Initial load
duke
parents:
diff changeset
710 tty->print_cr("--Float-|"PTR_FORMAT,new_sp);
a61af66fc99e Initial load
duke
parents:
diff changeset
711 tty->print_cr("---FP---|");
a61af66fc99e Initial load
duke
parents:
diff changeset
712 old_sp += incr*32; new_sp += incr*32; was_oops += incr*32;
a61af66fc99e Initial load
duke
parents:
diff changeset
713 for( int i2=0; i2<16; i2++ ) {
a61af66fc99e Initial load
duke
parents:
diff changeset
714 tty->print("call %c%d |"PTR_FORMAT" ","LI"[i2>>3],i2&7,new_sp); print_ptrs(*old_sp++,*new_sp++,*was_oops++); }
a61af66fc99e Initial load
duke
parents:
diff changeset
715 tty->print_cr("");
a61af66fc99e Initial load
duke
parents:
diff changeset
716 }
a61af66fc99e Initial load
duke
parents:
diff changeset
717 #endif // SPARC
a61af66fc99e Initial load
duke
parents:
diff changeset
718 #endif // PRODUCT
a61af66fc99e Initial load
duke
parents:
diff changeset
719
a61af66fc99e Initial load
duke
parents:
diff changeset
720
a61af66fc99e Initial load
duke
parents:
diff changeset
721 void SafepointSynchronize::handle_polling_page_exception(JavaThread *thread) {
a61af66fc99e Initial load
duke
parents:
diff changeset
722 assert(thread->is_Java_thread(), "polling reference encountered by VM thread");
a61af66fc99e Initial load
duke
parents:
diff changeset
723 assert(thread->thread_state() == _thread_in_Java, "should come from Java code");
a61af66fc99e Initial load
duke
parents:
diff changeset
724 assert(SafepointSynchronize::is_synchronizing(), "polling encountered outside safepoint synchronization");
a61af66fc99e Initial load
duke
parents:
diff changeset
725
a61af66fc99e Initial load
duke
parents:
diff changeset
726 // Uncomment this to get some serious before/after printing of the
a61af66fc99e Initial load
duke
parents:
diff changeset
727 // Sparc safepoint-blob frame structure.
a61af66fc99e Initial load
duke
parents:
diff changeset
728 /*
a61af66fc99e Initial load
duke
parents:
diff changeset
729 intptr_t* sp = thread->last_Java_sp();
a61af66fc99e Initial load
duke
parents:
diff changeset
730 intptr_t stack_copy[150];
a61af66fc99e Initial load
duke
parents:
diff changeset
731 for( int i=0; i<150; i++ ) stack_copy[i] = sp[i];
a61af66fc99e Initial load
duke
parents:
diff changeset
732 bool was_oops[150];
a61af66fc99e Initial load
duke
parents:
diff changeset
733 for( int i=0; i<150; i++ )
a61af66fc99e Initial load
duke
parents:
diff changeset
734 was_oops[i] = stack_copy[i] ? ((oop)stack_copy[i])->is_oop() : false;
a61af66fc99e Initial load
duke
parents:
diff changeset
735 */
a61af66fc99e Initial load
duke
parents:
diff changeset
736
a61af66fc99e Initial load
duke
parents:
diff changeset
737 if (ShowSafepointMsgs) {
a61af66fc99e Initial load
duke
parents:
diff changeset
738 tty->print("handle_polling_page_exception: ");
a61af66fc99e Initial load
duke
parents:
diff changeset
739 }
a61af66fc99e Initial load
duke
parents:
diff changeset
740
a61af66fc99e Initial load
duke
parents:
diff changeset
741 if (PrintSafepointStatistics) {
a61af66fc99e Initial load
duke
parents:
diff changeset
742 inc_page_trap_count();
a61af66fc99e Initial load
duke
parents:
diff changeset
743 }
a61af66fc99e Initial load
duke
parents:
diff changeset
744
a61af66fc99e Initial load
duke
parents:
diff changeset
745 ThreadSafepointState* state = thread->safepoint_state();
a61af66fc99e Initial load
duke
parents:
diff changeset
746
a61af66fc99e Initial load
duke
parents:
diff changeset
747 state->handle_polling_page_exception();
a61af66fc99e Initial load
duke
parents:
diff changeset
748 // print_me(sp,stack_copy,was_oops);
a61af66fc99e Initial load
duke
parents:
diff changeset
749 }
a61af66fc99e Initial load
duke
parents:
diff changeset
750
a61af66fc99e Initial load
duke
parents:
diff changeset
751
a61af66fc99e Initial load
duke
parents:
diff changeset
752 void SafepointSynchronize::print_safepoint_timeout(SafepointTimeoutReason reason) {
a61af66fc99e Initial load
duke
parents:
diff changeset
753 if (!timeout_error_printed) {
a61af66fc99e Initial load
duke
parents:
diff changeset
754 timeout_error_printed = true;
a61af66fc99e Initial load
duke
parents:
diff changeset
755 // Print out the thread infor which didn't reach the safepoint for debugging
a61af66fc99e Initial load
duke
parents:
diff changeset
756 // purposes (useful when there are lots of threads in the debugger).
a61af66fc99e Initial load
duke
parents:
diff changeset
757 tty->print_cr("");
a61af66fc99e Initial load
duke
parents:
diff changeset
758 tty->print_cr("# SafepointSynchronize::begin: Timeout detected:");
a61af66fc99e Initial load
duke
parents:
diff changeset
759 if (reason == _spinning_timeout) {
a61af66fc99e Initial load
duke
parents:
diff changeset
760 tty->print_cr("# SafepointSynchronize::begin: Timed out while spinning to reach a safepoint.");
a61af66fc99e Initial load
duke
parents:
diff changeset
761 } else if (reason == _blocking_timeout) {
a61af66fc99e Initial load
duke
parents:
diff changeset
762 tty->print_cr("# SafepointSynchronize::begin: Timed out while waiting for threads to stop.");
a61af66fc99e Initial load
duke
parents:
diff changeset
763 }
a61af66fc99e Initial load
duke
parents:
diff changeset
764
a61af66fc99e Initial load
duke
parents:
diff changeset
765 tty->print_cr("# SafepointSynchronize::begin: Threads which did not reach the safepoint:");
a61af66fc99e Initial load
duke
parents:
diff changeset
766 ThreadSafepointState *cur_state;
a61af66fc99e Initial load
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parents:
diff changeset
767 ResourceMark rm;
a61af66fc99e Initial load
duke
parents:
diff changeset
768 for(JavaThread *cur_thread = Threads::first(); cur_thread;
a61af66fc99e Initial load
duke
parents:
diff changeset
769 cur_thread = cur_thread->next()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
770 cur_state = cur_thread->safepoint_state();
a61af66fc99e Initial load
duke
parents:
diff changeset
771
a61af66fc99e Initial load
duke
parents:
diff changeset
772 if (cur_thread->thread_state() != _thread_blocked &&
a61af66fc99e Initial load
duke
parents:
diff changeset
773 ((reason == _spinning_timeout && cur_state->is_running()) ||
a61af66fc99e Initial load
duke
parents:
diff changeset
774 (reason == _blocking_timeout && !cur_state->has_called_back()))) {
a61af66fc99e Initial load
duke
parents:
diff changeset
775 tty->print("# ");
a61af66fc99e Initial load
duke
parents:
diff changeset
776 cur_thread->print();
a61af66fc99e Initial load
duke
parents:
diff changeset
777 tty->print_cr("");
a61af66fc99e Initial load
duke
parents:
diff changeset
778 }
a61af66fc99e Initial load
duke
parents:
diff changeset
779 }
a61af66fc99e Initial load
duke
parents:
diff changeset
780 tty->print_cr("# SafepointSynchronize::begin: (End of list)");
a61af66fc99e Initial load
duke
parents:
diff changeset
781 }
a61af66fc99e Initial load
duke
parents:
diff changeset
782
a61af66fc99e Initial load
duke
parents:
diff changeset
783 // To debug the long safepoint, specify both DieOnSafepointTimeout &
a61af66fc99e Initial load
duke
parents:
diff changeset
784 // ShowMessageBoxOnError.
a61af66fc99e Initial load
duke
parents:
diff changeset
785 if (DieOnSafepointTimeout) {
a61af66fc99e Initial load
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parents:
diff changeset
786 char msg[1024];
a61af66fc99e Initial load
duke
parents:
diff changeset
787 VM_Operation *op = VMThread::vm_operation();
513
2328d1d3f8cf 6781583: Hotspot build fails on linux 64 bit platform with gcc 4.3.2
xlu
parents: 0
diff changeset
788 sprintf(msg, "Safepoint sync time longer than " INTX_FORMAT "ms detected when executing %s.",
0
a61af66fc99e Initial load
duke
parents:
diff changeset
789 SafepointTimeoutDelay,
a61af66fc99e Initial load
duke
parents:
diff changeset
790 op != NULL ? op->name() : "no vm operation");
a61af66fc99e Initial load
duke
parents:
diff changeset
791 fatal(msg);
a61af66fc99e Initial load
duke
parents:
diff changeset
792 }
a61af66fc99e Initial load
duke
parents:
diff changeset
793 }
a61af66fc99e Initial load
duke
parents:
diff changeset
794
a61af66fc99e Initial load
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parents:
diff changeset
795
a61af66fc99e Initial load
duke
parents:
diff changeset
796 // -------------------------------------------------------------------------------------------------------
a61af66fc99e Initial load
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parents:
diff changeset
797 // Implementation of ThreadSafepointState
a61af66fc99e Initial load
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parents:
diff changeset
798
a61af66fc99e Initial load
duke
parents:
diff changeset
799 ThreadSafepointState::ThreadSafepointState(JavaThread *thread) {
a61af66fc99e Initial load
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parents:
diff changeset
800 _thread = thread;
a61af66fc99e Initial load
duke
parents:
diff changeset
801 _type = _running;
a61af66fc99e Initial load
duke
parents:
diff changeset
802 _has_called_back = false;
a61af66fc99e Initial load
duke
parents:
diff changeset
803 _at_poll_safepoint = false;
a61af66fc99e Initial load
duke
parents:
diff changeset
804 }
a61af66fc99e Initial load
duke
parents:
diff changeset
805
a61af66fc99e Initial load
duke
parents:
diff changeset
806 void ThreadSafepointState::create(JavaThread *thread) {
a61af66fc99e Initial load
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parents:
diff changeset
807 ThreadSafepointState *state = new ThreadSafepointState(thread);
a61af66fc99e Initial load
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parents:
diff changeset
808 thread->set_safepoint_state(state);
a61af66fc99e Initial load
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parents:
diff changeset
809 }
a61af66fc99e Initial load
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parents:
diff changeset
810
a61af66fc99e Initial load
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parents:
diff changeset
811 void ThreadSafepointState::destroy(JavaThread *thread) {
a61af66fc99e Initial load
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parents:
diff changeset
812 if (thread->safepoint_state()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
813 delete(thread->safepoint_state());
a61af66fc99e Initial load
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parents:
diff changeset
814 thread->set_safepoint_state(NULL);
a61af66fc99e Initial load
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parents:
diff changeset
815 }
a61af66fc99e Initial load
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parents:
diff changeset
816 }
a61af66fc99e Initial load
duke
parents:
diff changeset
817
a61af66fc99e Initial load
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parents:
diff changeset
818 void ThreadSafepointState::examine_state_of_thread() {
a61af66fc99e Initial load
duke
parents:
diff changeset
819 assert(is_running(), "better be running or just have hit safepoint poll");
a61af66fc99e Initial load
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parents:
diff changeset
820
a61af66fc99e Initial load
duke
parents:
diff changeset
821 JavaThreadState state = _thread->thread_state();
a61af66fc99e Initial load
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parents:
diff changeset
822
1727
da877bdc9000 6975006: assert(check.is_deoptimized_frame()) failed: missed deopt
never
parents: 1552
diff changeset
823 // Save the state at the start of safepoint processing.
da877bdc9000 6975006: assert(check.is_deoptimized_frame()) failed: missed deopt
never
parents: 1552
diff changeset
824 _orig_thread_state = state;
da877bdc9000 6975006: assert(check.is_deoptimized_frame()) failed: missed deopt
never
parents: 1552
diff changeset
825
0
a61af66fc99e Initial load
duke
parents:
diff changeset
826 // Check for a thread that is suspended. Note that thread resume tries
a61af66fc99e Initial load
duke
parents:
diff changeset
827 // to grab the Threads_lock which we own here, so a thread cannot be
a61af66fc99e Initial load
duke
parents:
diff changeset
828 // resumed during safepoint synchronization.
a61af66fc99e Initial load
duke
parents:
diff changeset
829
979
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
830 // We check to see if this thread is suspended without locking to
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
831 // avoid deadlocking with a third thread that is waiting for this
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
832 // thread to be suspended. The third thread can notice the safepoint
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
833 // that we're trying to start at the beginning of its SR_lock->wait()
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
834 // call. If that happens, then the third thread will block on the
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
835 // safepoint while still holding the underlying SR_lock. We won't be
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
836 // able to get the SR_lock and we'll deadlock.
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
837 //
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
838 // We don't need to grab the SR_lock here for two reasons:
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
839 // 1) The suspend flags are both volatile and are set with an
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
840 // Atomic::cmpxchg() call so we should see the suspended
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
841 // state right away.
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
842 // 2) We're being called from the safepoint polling loop; if
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
843 // we don't see the suspended state on this iteration, then
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
844 // we'll come around again.
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
845 //
87770dcf831b 6876794: 4/4 sp07t002 hangs very intermittently
dcubed
parents: 845
diff changeset
846 bool is_suspended = _thread->is_ext_suspended();
0
a61af66fc99e Initial load
duke
parents:
diff changeset
847 if (is_suspended) {
a61af66fc99e Initial load
duke
parents:
diff changeset
848 roll_forward(_at_safepoint);
a61af66fc99e Initial load
duke
parents:
diff changeset
849 return;
a61af66fc99e Initial load
duke
parents:
diff changeset
850 }
a61af66fc99e Initial load
duke
parents:
diff changeset
851
a61af66fc99e Initial load
duke
parents:
diff changeset
852 // Some JavaThread states have an initial safepoint state of
a61af66fc99e Initial load
duke
parents:
diff changeset
853 // running, but are actually at a safepoint. We will happily
a61af66fc99e Initial load
duke
parents:
diff changeset
854 // agree and update the safepoint state here.
a61af66fc99e Initial load
duke
parents:
diff changeset
855 if (SafepointSynchronize::safepoint_safe(_thread, state)) {
a61af66fc99e Initial load
duke
parents:
diff changeset
856 roll_forward(_at_safepoint);
a61af66fc99e Initial load
duke
parents:
diff changeset
857 return;
a61af66fc99e Initial load
duke
parents:
diff changeset
858 }
a61af66fc99e Initial load
duke
parents:
diff changeset
859
a61af66fc99e Initial load
duke
parents:
diff changeset
860 if (state == _thread_in_vm) {
a61af66fc99e Initial load
duke
parents:
diff changeset
861 roll_forward(_call_back);
a61af66fc99e Initial load
duke
parents:
diff changeset
862 return;
a61af66fc99e Initial load
duke
parents:
diff changeset
863 }
a61af66fc99e Initial load
duke
parents:
diff changeset
864
a61af66fc99e Initial load
duke
parents:
diff changeset
865 // All other thread states will continue to run until they
a61af66fc99e Initial load
duke
parents:
diff changeset
866 // transition and self-block in state _blocked
a61af66fc99e Initial load
duke
parents:
diff changeset
867 // Safepoint polling in compiled code causes the Java threads to do the same.
a61af66fc99e Initial load
duke
parents:
diff changeset
868 // Note: new threads may require a malloc so they must be allowed to finish
a61af66fc99e Initial load
duke
parents:
diff changeset
869
a61af66fc99e Initial load
duke
parents:
diff changeset
870 assert(is_running(), "examine_state_of_thread on non-running thread");
a61af66fc99e Initial load
duke
parents:
diff changeset
871 return;
a61af66fc99e Initial load
duke
parents:
diff changeset
872 }
a61af66fc99e Initial load
duke
parents:
diff changeset
873
a61af66fc99e Initial load
duke
parents:
diff changeset
874 // Returns true is thread could not be rolled forward at present position.
a61af66fc99e Initial load
duke
parents:
diff changeset
875 void ThreadSafepointState::roll_forward(suspend_type type) {
a61af66fc99e Initial load
duke
parents:
diff changeset
876 _type = type;
a61af66fc99e Initial load
duke
parents:
diff changeset
877
a61af66fc99e Initial load
duke
parents:
diff changeset
878 switch(_type) {
a61af66fc99e Initial load
duke
parents:
diff changeset
879 case _at_safepoint:
a61af66fc99e Initial load
duke
parents:
diff changeset
880 SafepointSynchronize::signal_thread_at_safepoint();
a61af66fc99e Initial load
duke
parents:
diff changeset
881 break;
a61af66fc99e Initial load
duke
parents:
diff changeset
882
a61af66fc99e Initial load
duke
parents:
diff changeset
883 case _call_back:
a61af66fc99e Initial load
duke
parents:
diff changeset
884 set_has_called_back(false);
a61af66fc99e Initial load
duke
parents:
diff changeset
885 break;
a61af66fc99e Initial load
duke
parents:
diff changeset
886
a61af66fc99e Initial load
duke
parents:
diff changeset
887 case _running:
a61af66fc99e Initial load
duke
parents:
diff changeset
888 default:
a61af66fc99e Initial load
duke
parents:
diff changeset
889 ShouldNotReachHere();
a61af66fc99e Initial load
duke
parents:
diff changeset
890 }
a61af66fc99e Initial load
duke
parents:
diff changeset
891 }
a61af66fc99e Initial load
duke
parents:
diff changeset
892
a61af66fc99e Initial load
duke
parents:
diff changeset
893 void ThreadSafepointState::restart() {
a61af66fc99e Initial load
duke
parents:
diff changeset
894 switch(type()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
895 case _at_safepoint:
a61af66fc99e Initial load
duke
parents:
diff changeset
896 case _call_back:
a61af66fc99e Initial load
duke
parents:
diff changeset
897 break;
a61af66fc99e Initial load
duke
parents:
diff changeset
898
a61af66fc99e Initial load
duke
parents:
diff changeset
899 case _running:
a61af66fc99e Initial load
duke
parents:
diff changeset
900 default:
a61af66fc99e Initial load
duke
parents:
diff changeset
901 tty->print_cr("restart thread "INTPTR_FORMAT" with state %d",
a61af66fc99e Initial load
duke
parents:
diff changeset
902 _thread, _type);
a61af66fc99e Initial load
duke
parents:
diff changeset
903 _thread->print();
a61af66fc99e Initial load
duke
parents:
diff changeset
904 ShouldNotReachHere();
a61af66fc99e Initial load
duke
parents:
diff changeset
905 }
a61af66fc99e Initial load
duke
parents:
diff changeset
906 _type = _running;
a61af66fc99e Initial load
duke
parents:
diff changeset
907 set_has_called_back(false);
a61af66fc99e Initial load
duke
parents:
diff changeset
908 }
a61af66fc99e Initial load
duke
parents:
diff changeset
909
a61af66fc99e Initial load
duke
parents:
diff changeset
910
a61af66fc99e Initial load
duke
parents:
diff changeset
911 void ThreadSafepointState::print_on(outputStream *st) const {
a61af66fc99e Initial load
duke
parents:
diff changeset
912 const char *s;
a61af66fc99e Initial load
duke
parents:
diff changeset
913
a61af66fc99e Initial load
duke
parents:
diff changeset
914 switch(_type) {
a61af66fc99e Initial load
duke
parents:
diff changeset
915 case _running : s = "_running"; break;
a61af66fc99e Initial load
duke
parents:
diff changeset
916 case _at_safepoint : s = "_at_safepoint"; break;
a61af66fc99e Initial load
duke
parents:
diff changeset
917 case _call_back : s = "_call_back"; break;
a61af66fc99e Initial load
duke
parents:
diff changeset
918 default:
a61af66fc99e Initial load
duke
parents:
diff changeset
919 ShouldNotReachHere();
a61af66fc99e Initial load
duke
parents:
diff changeset
920 }
a61af66fc99e Initial load
duke
parents:
diff changeset
921
a61af66fc99e Initial load
duke
parents:
diff changeset
922 st->print_cr("Thread: " INTPTR_FORMAT
a61af66fc99e Initial load
duke
parents:
diff changeset
923 " [0x%2x] State: %s _has_called_back %d _at_poll_safepoint %d",
a61af66fc99e Initial load
duke
parents:
diff changeset
924 _thread, _thread->osthread()->thread_id(), s, _has_called_back,
a61af66fc99e Initial load
duke
parents:
diff changeset
925 _at_poll_safepoint);
a61af66fc99e Initial load
duke
parents:
diff changeset
926
a61af66fc99e Initial load
duke
parents:
diff changeset
927 _thread->print_thread_state_on(st);
a61af66fc99e Initial load
duke
parents:
diff changeset
928 }
a61af66fc99e Initial load
duke
parents:
diff changeset
929
a61af66fc99e Initial load
duke
parents:
diff changeset
930
a61af66fc99e Initial load
duke
parents:
diff changeset
931 // ---------------------------------------------------------------------------------------------------------------------
a61af66fc99e Initial load
duke
parents:
diff changeset
932
a61af66fc99e Initial load
duke
parents:
diff changeset
933 // Block the thread at the safepoint poll or poll return.
a61af66fc99e Initial load
duke
parents:
diff changeset
934 void ThreadSafepointState::handle_polling_page_exception() {
a61af66fc99e Initial load
duke
parents:
diff changeset
935
a61af66fc99e Initial load
duke
parents:
diff changeset
936 // Check state. block() will set thread state to thread_in_vm which will
a61af66fc99e Initial load
duke
parents:
diff changeset
937 // cause the safepoint state _type to become _call_back.
a61af66fc99e Initial load
duke
parents:
diff changeset
938 assert(type() == ThreadSafepointState::_running,
a61af66fc99e Initial load
duke
parents:
diff changeset
939 "polling page exception on thread not running state");
a61af66fc99e Initial load
duke
parents:
diff changeset
940
a61af66fc99e Initial load
duke
parents:
diff changeset
941 // Step 1: Find the nmethod from the return address
a61af66fc99e Initial load
duke
parents:
diff changeset
942 if (ShowSafepointMsgs && Verbose) {
a61af66fc99e Initial load
duke
parents:
diff changeset
943 tty->print_cr("Polling page exception at " INTPTR_FORMAT, thread()->saved_exception_pc());
a61af66fc99e Initial load
duke
parents:
diff changeset
944 }
a61af66fc99e Initial load
duke
parents:
diff changeset
945 address real_return_addr = thread()->saved_exception_pc();
a61af66fc99e Initial load
duke
parents:
diff changeset
946
a61af66fc99e Initial load
duke
parents:
diff changeset
947 CodeBlob *cb = CodeCache::find_blob(real_return_addr);
a61af66fc99e Initial load
duke
parents:
diff changeset
948 assert(cb != NULL && cb->is_nmethod(), "return address should be in nmethod");
a61af66fc99e Initial load
duke
parents:
diff changeset
949 nmethod* nm = (nmethod*)cb;
a61af66fc99e Initial load
duke
parents:
diff changeset
950
a61af66fc99e Initial load
duke
parents:
diff changeset
951 // Find frame of caller
a61af66fc99e Initial load
duke
parents:
diff changeset
952 frame stub_fr = thread()->last_frame();
a61af66fc99e Initial load
duke
parents:
diff changeset
953 CodeBlob* stub_cb = stub_fr.cb();
a61af66fc99e Initial load
duke
parents:
diff changeset
954 assert(stub_cb->is_safepoint_stub(), "must be a safepoint stub");
a61af66fc99e Initial load
duke
parents:
diff changeset
955 RegisterMap map(thread(), true);
a61af66fc99e Initial load
duke
parents:
diff changeset
956 frame caller_fr = stub_fr.sender(&map);
a61af66fc99e Initial load
duke
parents:
diff changeset
957
a61af66fc99e Initial load
duke
parents:
diff changeset
958 // Should only be poll_return or poll
a61af66fc99e Initial load
duke
parents:
diff changeset
959 assert( nm->is_at_poll_or_poll_return(real_return_addr), "should not be at call" );
a61af66fc99e Initial load
duke
parents:
diff changeset
960
a61af66fc99e Initial load
duke
parents:
diff changeset
961 // This is a poll immediately before a return. The exception handling code
a61af66fc99e Initial load
duke
parents:
diff changeset
962 // has already had the effect of causing the return to occur, so the execution
a61af66fc99e Initial load
duke
parents:
diff changeset
963 // will continue immediately after the call. In addition, the oopmap at the
a61af66fc99e Initial load
duke
parents:
diff changeset
964 // return point does not mark the return value as an oop (if it is), so
a61af66fc99e Initial load
duke
parents:
diff changeset
965 // it needs a handle here to be updated.
a61af66fc99e Initial load
duke
parents:
diff changeset
966 if( nm->is_at_poll_return(real_return_addr) ) {
a61af66fc99e Initial load
duke
parents:
diff changeset
967 // See if return type is an oop.
a61af66fc99e Initial load
duke
parents:
diff changeset
968 bool return_oop = nm->method()->is_returning_oop();
a61af66fc99e Initial load
duke
parents:
diff changeset
969 Handle return_value;
a61af66fc99e Initial load
duke
parents:
diff changeset
970 if (return_oop) {
a61af66fc99e Initial load
duke
parents:
diff changeset
971 // The oop result has been saved on the stack together with all
a61af66fc99e Initial load
duke
parents:
diff changeset
972 // the other registers. In order to preserve it over GCs we need
a61af66fc99e Initial load
duke
parents:
diff changeset
973 // to keep it in a handle.
a61af66fc99e Initial load
duke
parents:
diff changeset
974 oop result = caller_fr.saved_oop_result(&map);
a61af66fc99e Initial load
duke
parents:
diff changeset
975 assert(result == NULL || result->is_oop(), "must be oop");
a61af66fc99e Initial load
duke
parents:
diff changeset
976 return_value = Handle(thread(), result);
a61af66fc99e Initial load
duke
parents:
diff changeset
977 assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
a61af66fc99e Initial load
duke
parents:
diff changeset
978 }
a61af66fc99e Initial load
duke
parents:
diff changeset
979
a61af66fc99e Initial load
duke
parents:
diff changeset
980 // Block the thread
a61af66fc99e Initial load
duke
parents:
diff changeset
981 SafepointSynchronize::block(thread());
a61af66fc99e Initial load
duke
parents:
diff changeset
982
a61af66fc99e Initial load
duke
parents:
diff changeset
983 // restore oop result, if any
a61af66fc99e Initial load
duke
parents:
diff changeset
984 if (return_oop) {
a61af66fc99e Initial load
duke
parents:
diff changeset
985 caller_fr.set_saved_oop_result(&map, return_value());
a61af66fc99e Initial load
duke
parents:
diff changeset
986 }
a61af66fc99e Initial load
duke
parents:
diff changeset
987 }
a61af66fc99e Initial load
duke
parents:
diff changeset
988
a61af66fc99e Initial load
duke
parents:
diff changeset
989 // This is a safepoint poll. Verify the return address and block.
a61af66fc99e Initial load
duke
parents:
diff changeset
990 else {
a61af66fc99e Initial load
duke
parents:
diff changeset
991 set_at_poll_safepoint(true);
a61af66fc99e Initial load
duke
parents:
diff changeset
992
a61af66fc99e Initial load
duke
parents:
diff changeset
993 // verify the blob built the "return address" correctly
a61af66fc99e Initial load
duke
parents:
diff changeset
994 assert(real_return_addr == caller_fr.pc(), "must match");
a61af66fc99e Initial load
duke
parents:
diff changeset
995
a61af66fc99e Initial load
duke
parents:
diff changeset
996 // Block the thread
a61af66fc99e Initial load
duke
parents:
diff changeset
997 SafepointSynchronize::block(thread());
a61af66fc99e Initial load
duke
parents:
diff changeset
998 set_at_poll_safepoint(false);
a61af66fc99e Initial load
duke
parents:
diff changeset
999
a61af66fc99e Initial load
duke
parents:
diff changeset
1000 // If we have a pending async exception deoptimize the frame
a61af66fc99e Initial load
duke
parents:
diff changeset
1001 // as otherwise we may never deliver it.
a61af66fc99e Initial load
duke
parents:
diff changeset
1002 if (thread()->has_async_condition()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1003 ThreadInVMfromJavaNoAsyncException __tiv(thread());
1905
ce6848d0666d 6968367: can_post_on_exceptions is still using VM_DeoptimizeFrame in some places
never
parents: 1783
diff changeset
1004 Deoptimization::deoptimize_frame(thread(), caller_fr.id());
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1005 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1006
a61af66fc99e Initial load
duke
parents:
diff changeset
1007 // If an exception has been installed we must check for a pending deoptimization
a61af66fc99e Initial load
duke
parents:
diff changeset
1008 // Deoptimize frame if exception has been thrown.
a61af66fc99e Initial load
duke
parents:
diff changeset
1009
a61af66fc99e Initial load
duke
parents:
diff changeset
1010 if (thread()->has_pending_exception() ) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1011 RegisterMap map(thread(), true);
a61af66fc99e Initial load
duke
parents:
diff changeset
1012 frame caller_fr = stub_fr.sender(&map);
a61af66fc99e Initial load
duke
parents:
diff changeset
1013 if (caller_fr.is_deoptimized_frame()) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1014 // The exception patch will destroy registers that are still
a61af66fc99e Initial load
duke
parents:
diff changeset
1015 // live and will be needed during deoptimization. Defer the
a61af66fc99e Initial load
duke
parents:
diff changeset
1016 // Async exception should have defered the exception until the
a61af66fc99e Initial load
duke
parents:
diff changeset
1017 // next safepoint which will be detected when we get into
a61af66fc99e Initial load
duke
parents:
diff changeset
1018 // the interpreter so if we have an exception now things
a61af66fc99e Initial load
duke
parents:
diff changeset
1019 // are messed up.
a61af66fc99e Initial load
duke
parents:
diff changeset
1020
a61af66fc99e Initial load
duke
parents:
diff changeset
1021 fatal("Exception installed and deoptimization is pending");
a61af66fc99e Initial load
duke
parents:
diff changeset
1022 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1023 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1024 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1025 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1026
a61af66fc99e Initial load
duke
parents:
diff changeset
1027
a61af66fc99e Initial load
duke
parents:
diff changeset
1028 //
a61af66fc99e Initial load
duke
parents:
diff changeset
1029 // Statistics & Instrumentations
a61af66fc99e Initial load
duke
parents:
diff changeset
1030 //
a61af66fc99e Initial load
duke
parents:
diff changeset
1031 SafepointSynchronize::SafepointStats* SafepointSynchronize::_safepoint_stats = NULL;
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1032 jlong SafepointSynchronize::_safepoint_begin_time = 0;
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1033 int SafepointSynchronize::_cur_stat_index = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
1034 julong SafepointSynchronize::_safepoint_reasons[VM_Operation::VMOp_Terminating];
a61af66fc99e Initial load
duke
parents:
diff changeset
1035 julong SafepointSynchronize::_coalesced_vmop_count = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
1036 jlong SafepointSynchronize::_max_sync_time = 0;
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1037 jlong SafepointSynchronize::_max_vmop_time = 0;
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1038 float SafepointSynchronize::_ts_of_current_safepoint = 0.0f;
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1039
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1040 static jlong cleanup_end_time = 0;
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1041 static bool need_to_track_page_armed_status = false;
a61af66fc99e Initial load
duke
parents:
diff changeset
1042 static bool init_done = false;
a61af66fc99e Initial load
duke
parents:
diff changeset
1043
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1044 // Helper method to print the header.
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1045 static void print_header() {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1046 tty->print(" vmop "
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1047 "[threads: total initially_running wait_to_block] ");
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1048 tty->print("[time: spin block sync cleanup vmop] ");
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1049
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1050 // no page armed status printed out if it is always armed.
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1051 if (need_to_track_page_armed_status) {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1052 tty->print("page_armed ");
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1053 }
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1054
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1055 tty->print_cr("page_trap_count");
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1056 }
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1057
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1058 void SafepointSynchronize::deferred_initialize_stat() {
a61af66fc99e Initial load
duke
parents:
diff changeset
1059 if (init_done) return;
a61af66fc99e Initial load
duke
parents:
diff changeset
1060
a61af66fc99e Initial load
duke
parents:
diff changeset
1061 if (PrintSafepointStatisticsCount <= 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1062 fatal("Wrong PrintSafepointStatisticsCount");
a61af66fc99e Initial load
duke
parents:
diff changeset
1063 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1064
a61af66fc99e Initial load
duke
parents:
diff changeset
1065 // If PrintSafepointStatisticsTimeout is specified, the statistics data will
a61af66fc99e Initial load
duke
parents:
diff changeset
1066 // be printed right away, in which case, _safepoint_stats will regress to
a61af66fc99e Initial load
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parents:
diff changeset
1067 // a single element array. Otherwise, it is a circular ring buffer with default
a61af66fc99e Initial load
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parents:
diff changeset
1068 // size of PrintSafepointStatisticsCount.
a61af66fc99e Initial load
duke
parents:
diff changeset
1069 int stats_array_size;
a61af66fc99e Initial load
duke
parents:
diff changeset
1070 if (PrintSafepointStatisticsTimeout > 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1071 stats_array_size = 1;
a61af66fc99e Initial load
duke
parents:
diff changeset
1072 PrintSafepointStatistics = true;
a61af66fc99e Initial load
duke
parents:
diff changeset
1073 } else {
a61af66fc99e Initial load
duke
parents:
diff changeset
1074 stats_array_size = PrintSafepointStatisticsCount;
a61af66fc99e Initial load
duke
parents:
diff changeset
1075 }
a61af66fc99e Initial load
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parents:
diff changeset
1076 _safepoint_stats = (SafepointStats*)os::malloc(stats_array_size
a61af66fc99e Initial load
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parents:
diff changeset
1077 * sizeof(SafepointStats));
a61af66fc99e Initial load
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parents:
diff changeset
1078 guarantee(_safepoint_stats != NULL,
a61af66fc99e Initial load
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parents:
diff changeset
1079 "not enough memory for safepoint instrumentation data");
a61af66fc99e Initial load
duke
parents:
diff changeset
1080
a61af66fc99e Initial load
duke
parents:
diff changeset
1081 if (UseCompilerSafepoints && DeferPollingPageLoopCount >= 0) {
a61af66fc99e Initial load
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parents:
diff changeset
1082 need_to_track_page_armed_status = true;
a61af66fc99e Initial load
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parents:
diff changeset
1083 }
a61af66fc99e Initial load
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parents:
diff changeset
1084 init_done = true;
a61af66fc99e Initial load
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parents:
diff changeset
1085 }
a61af66fc99e Initial load
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parents:
diff changeset
1086
a61af66fc99e Initial load
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parents:
diff changeset
1087 void SafepointSynchronize::begin_statistics(int nof_threads, int nof_running) {
1003
528d98fe1037 6880029: JDK 1.6.0_u14p Application crashed very early
xlu
parents: 979
diff changeset
1088 assert(init_done, "safepoint statistics array hasn't been initialized");
0
a61af66fc99e Initial load
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parents:
diff changeset
1089 SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];
a61af66fc99e Initial load
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parents:
diff changeset
1090
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1091 spstat->_time_stamp = _ts_of_current_safepoint;
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1092
0
a61af66fc99e Initial load
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parents:
diff changeset
1093 VM_Operation *op = VMThread::vm_operation();
a61af66fc99e Initial load
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parents:
diff changeset
1094 spstat->_vmop_type = (op != NULL ? op->type() : -1);
a61af66fc99e Initial load
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parents:
diff changeset
1095 if (op != NULL) {
a61af66fc99e Initial load
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parents:
diff changeset
1096 _safepoint_reasons[spstat->_vmop_type]++;
a61af66fc99e Initial load
duke
parents:
diff changeset
1097 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1098
a61af66fc99e Initial load
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parents:
diff changeset
1099 spstat->_nof_total_threads = nof_threads;
a61af66fc99e Initial load
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parents:
diff changeset
1100 spstat->_nof_initial_running_threads = nof_running;
a61af66fc99e Initial load
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parents:
diff changeset
1101 spstat->_nof_threads_hit_page_trap = 0;
a61af66fc99e Initial load
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parents:
diff changeset
1102
a61af66fc99e Initial load
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parents:
diff changeset
1103 // Records the start time of spinning. The real time spent on spinning
a61af66fc99e Initial load
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parents:
diff changeset
1104 // will be adjusted when spin is done. Same trick is applied for time
a61af66fc99e Initial load
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parents:
diff changeset
1105 // spent on waiting for threads to block.
a61af66fc99e Initial load
duke
parents:
diff changeset
1106 if (nof_running != 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1107 spstat->_time_to_spin = os::javaTimeNanos();
a61af66fc99e Initial load
duke
parents:
diff changeset
1108 } else {
a61af66fc99e Initial load
duke
parents:
diff changeset
1109 spstat->_time_to_spin = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
1110 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1111 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1112
a61af66fc99e Initial load
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parents:
diff changeset
1113 void SafepointSynchronize::update_statistics_on_spin_end() {
a61af66fc99e Initial load
duke
parents:
diff changeset
1114 SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];
a61af66fc99e Initial load
duke
parents:
diff changeset
1115
a61af66fc99e Initial load
duke
parents:
diff changeset
1116 jlong cur_time = os::javaTimeNanos();
a61af66fc99e Initial load
duke
parents:
diff changeset
1117
a61af66fc99e Initial load
duke
parents:
diff changeset
1118 spstat->_nof_threads_wait_to_block = _waiting_to_block;
a61af66fc99e Initial load
duke
parents:
diff changeset
1119 if (spstat->_nof_initial_running_threads != 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1120 spstat->_time_to_spin = cur_time - spstat->_time_to_spin;
a61af66fc99e Initial load
duke
parents:
diff changeset
1121 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1122
a61af66fc99e Initial load
duke
parents:
diff changeset
1123 if (need_to_track_page_armed_status) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1124 spstat->_page_armed = (PageArmed == 1);
a61af66fc99e Initial load
duke
parents:
diff changeset
1125 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1126
a61af66fc99e Initial load
duke
parents:
diff changeset
1127 // Records the start time of waiting for to block. Updated when block is done.
a61af66fc99e Initial load
duke
parents:
diff changeset
1128 if (_waiting_to_block != 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1129 spstat->_time_to_wait_to_block = cur_time;
a61af66fc99e Initial load
duke
parents:
diff changeset
1130 } else {
a61af66fc99e Initial load
duke
parents:
diff changeset
1131 spstat->_time_to_wait_to_block = 0;
a61af66fc99e Initial load
duke
parents:
diff changeset
1132 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1133 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1134
a61af66fc99e Initial load
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parents:
diff changeset
1135 void SafepointSynchronize::update_statistics_on_sync_end(jlong end_time) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1136 SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];
a61af66fc99e Initial load
duke
parents:
diff changeset
1137
a61af66fc99e Initial load
duke
parents:
diff changeset
1138 if (spstat->_nof_threads_wait_to_block != 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1139 spstat->_time_to_wait_to_block = end_time -
a61af66fc99e Initial load
duke
parents:
diff changeset
1140 spstat->_time_to_wait_to_block;
a61af66fc99e Initial load
duke
parents:
diff changeset
1141 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1142
a61af66fc99e Initial load
duke
parents:
diff changeset
1143 // Records the end time of sync which will be used to calculate the total
a61af66fc99e Initial load
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parents:
diff changeset
1144 // vm operation time. Again, the real time spending in syncing will be deducted
a61af66fc99e Initial load
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parents:
diff changeset
1145 // from the start of the sync time later when end_statistics is called.
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1146 spstat->_time_to_sync = end_time - _safepoint_begin_time;
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1147 if (spstat->_time_to_sync > _max_sync_time) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1148 _max_sync_time = spstat->_time_to_sync;
a61af66fc99e Initial load
duke
parents:
diff changeset
1149 }
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1150
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1151 spstat->_time_to_do_cleanups = end_time;
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1152 }
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1153
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1154 void SafepointSynchronize::update_statistics_on_cleanup_end(jlong end_time) {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1155 SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1156
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1157 // Record how long spent in cleanup tasks.
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1158 spstat->_time_to_do_cleanups = end_time - spstat->_time_to_do_cleanups;
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1159
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1160 cleanup_end_time = end_time;
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1161 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1162
a61af66fc99e Initial load
duke
parents:
diff changeset
1163 void SafepointSynchronize::end_statistics(jlong vmop_end_time) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1164 SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];
a61af66fc99e Initial load
duke
parents:
diff changeset
1165
a61af66fc99e Initial load
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parents:
diff changeset
1166 // Update the vm operation time.
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1167 spstat->_time_to_exec_vmop = vmop_end_time - cleanup_end_time;
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1168 if (spstat->_time_to_exec_vmop > _max_vmop_time) {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1169 _max_vmop_time = spstat->_time_to_exec_vmop;
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1170 }
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1171 // Only the sync time longer than the specified
a61af66fc99e Initial load
duke
parents:
diff changeset
1172 // PrintSafepointStatisticsTimeout will be printed out right away.
a61af66fc99e Initial load
duke
parents:
diff changeset
1173 // By default, it is -1 meaning all samples will be put into the list.
a61af66fc99e Initial load
duke
parents:
diff changeset
1174 if ( PrintSafepointStatisticsTimeout > 0) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1175 if (spstat->_time_to_sync > PrintSafepointStatisticsTimeout * MICROUNITS) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1176 print_statistics();
a61af66fc99e Initial load
duke
parents:
diff changeset
1177 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1178 } else {
a61af66fc99e Initial load
duke
parents:
diff changeset
1179 // The safepoint statistics will be printed out when the _safepoin_stats
a61af66fc99e Initial load
duke
parents:
diff changeset
1180 // array fills up.
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1181 if (_cur_stat_index == PrintSafepointStatisticsCount - 1) {
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1182 print_statistics();
a61af66fc99e Initial load
duke
parents:
diff changeset
1183 _cur_stat_index = 0;
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1184 } else {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1185 _cur_stat_index++;
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1186 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1187 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1188 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1189
a61af66fc99e Initial load
duke
parents:
diff changeset
1190 void SafepointSynchronize::print_statistics() {
a61af66fc99e Initial load
duke
parents:
diff changeset
1191 SafepointStats* sstats = _safepoint_stats;
a61af66fc99e Initial load
duke
parents:
diff changeset
1192
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1193 for (int index = 0; index <= _cur_stat_index; index++) {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1194 if (index % 30 == 0) {
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1195 print_header();
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1196 }
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1197 sstats = &_safepoint_stats[index];
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1198 tty->print("%.3f: ", sstats->_time_stamp);
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1199 tty->print("%-26s ["
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1200 INT32_FORMAT_W(8)INT32_FORMAT_W(11)INT32_FORMAT_W(15)
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1201 " ] ",
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1202 sstats->_vmop_type == -1 ? "no vm operation" :
a61af66fc99e Initial load
duke
parents:
diff changeset
1203 VM_Operation::name(sstats->_vmop_type),
a61af66fc99e Initial load
duke
parents:
diff changeset
1204 sstats->_nof_total_threads,
a61af66fc99e Initial load
duke
parents:
diff changeset
1205 sstats->_nof_initial_running_threads,
a61af66fc99e Initial load
duke
parents:
diff changeset
1206 sstats->_nof_threads_wait_to_block);
a61af66fc99e Initial load
duke
parents:
diff changeset
1207 // "/ MICROUNITS " is to convert the unit from nanos to millis.
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1208 tty->print(" ["
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1209 INT64_FORMAT_W(6)INT64_FORMAT_W(6)
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1210 INT64_FORMAT_W(6)INT64_FORMAT_W(6)
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1211 INT64_FORMAT_W(6)" ] ",
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1212 sstats->_time_to_spin / MICROUNITS,
a61af66fc99e Initial load
duke
parents:
diff changeset
1213 sstats->_time_to_wait_to_block / MICROUNITS,
a61af66fc99e Initial load
duke
parents:
diff changeset
1214 sstats->_time_to_sync / MICROUNITS,
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1215 sstats->_time_to_do_cleanups / MICROUNITS,
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1216 sstats->_time_to_exec_vmop / MICROUNITS);
0
a61af66fc99e Initial load
duke
parents:
diff changeset
1217
a61af66fc99e Initial load
duke
parents:
diff changeset
1218 if (need_to_track_page_armed_status) {
a61af66fc99e Initial load
duke
parents:
diff changeset
1219 tty->print(INT32_FORMAT" ", sstats->_page_armed);
a61af66fc99e Initial load
duke
parents:
diff changeset
1220 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1221 tty->print_cr(INT32_FORMAT" ", sstats->_nof_threads_hit_page_trap);
a61af66fc99e Initial load
duke
parents:
diff changeset
1222 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1223 }
a61af66fc99e Initial load
duke
parents:
diff changeset
1224
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1225 // This method will be called when VM exits. It will first call
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1226 // print_statistics to print out the rest of the sampling. Then
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1227 // it tries to summarize the sampling.
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1228 void SafepointSynchronize::print_stat_on_exit() {
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1229 if (_safepoint_stats == NULL) return;
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1230
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1231 SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];
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parents:
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1232
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1233 // During VM exit, end_statistics may not get called and in that
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1234 // case, if the sync time is less than PrintSafepointStatisticsTimeout,
a61af66fc99e Initial load
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parents:
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1235 // don't print it out.
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parents:
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1236 // Approximate the vm op time.
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1237 _safepoint_stats[_cur_stat_index]._time_to_exec_vmop =
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1238 os::javaTimeNanos() - cleanup_end_time;
0
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parents:
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1239
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parents:
diff changeset
1240 if ( PrintSafepointStatisticsTimeout < 0 ||
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parents:
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1241 spstat->_time_to_sync > PrintSafepointStatisticsTimeout * MICROUNITS) {
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parents:
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1242 print_statistics();
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parents:
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1243 }
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parents:
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1244 tty->print_cr("");
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parents:
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1245
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parents:
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1246 // Print out polling page sampling status.
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parents:
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1247 if (!need_to_track_page_armed_status) {
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parents:
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1248 if (UseCompilerSafepoints) {
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parents:
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1249 tty->print_cr("Polling page always armed");
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parents:
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1250 }
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parents:
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1251 } else {
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1252 tty->print_cr("Defer polling page loop count = %d\n",
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parents:
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1253 DeferPollingPageLoopCount);
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parents:
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1254 }
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parents:
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1255
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parents:
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1256 for (int index = 0; index < VM_Operation::VMOp_Terminating; index++) {
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parents:
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1257 if (_safepoint_reasons[index] != 0) {
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parents:
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1258 tty->print_cr("%-26s"UINT64_FORMAT_W(10), VM_Operation::name(index),
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parents:
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1259 _safepoint_reasons[index]);
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parents:
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1260 }
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parents:
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1261 }
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parents:
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1262
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parents:
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1263 tty->print_cr(UINT64_FORMAT_W(5)" VM operations coalesced during safepoint",
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parents:
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1264 _coalesced_vmop_count);
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parents:
diff changeset
1265 tty->print_cr("Maximum sync time "INT64_FORMAT_W(5)" ms",
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parents:
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1266 _max_sync_time / MICROUNITS);
1291
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1267 tty->print_cr("Maximum vm operation time (except for Exit VM operation) "
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1268 INT64_FORMAT_W(5)" ms",
4b0f2f4918ed 6933402: RFE: Improve PrintSafepointStatistics output to track cleanup time
xlu
parents: 1003
diff changeset
1269 _max_vmop_time / MICROUNITS);
0
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parents:
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1270 }
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parents:
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1271
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parents:
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1272 // ------------------------------------------------------------------------------------------------
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parents:
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1273 // Non-product code
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parents:
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1274
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parents:
diff changeset
1275 #ifndef PRODUCT
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parents:
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1276
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parents:
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1277 void SafepointSynchronize::print_state() {
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parents:
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1278 if (_state == _not_synchronized) {
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parents:
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1279 tty->print_cr("not synchronized");
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parents:
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1280 } else if (_state == _synchronizing || _state == _synchronized) {
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parents:
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1281 tty->print_cr("State: %s", (_state == _synchronizing) ? "synchronizing" :
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parents:
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1282 "synchronized");
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parents:
diff changeset
1283
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parents:
diff changeset
1284 for(JavaThread *cur = Threads::first(); cur; cur = cur->next()) {
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parents:
diff changeset
1285 cur->safepoint_state()->print();
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parents:
diff changeset
1286 }
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parents:
diff changeset
1287 }
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parents:
diff changeset
1288 }
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parents:
diff changeset
1289
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parents:
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1290 void SafepointSynchronize::safepoint_msg(const char* format, ...) {
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parents:
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1291 if (ShowSafepointMsgs) {
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parents:
diff changeset
1292 va_list ap;
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parents:
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1293 va_start(ap, format);
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parents:
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1294 tty->vprint_cr(format, ap);
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parents:
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1295 va_end(ap);
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parents:
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1296 }
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parents:
diff changeset
1297 }
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parents:
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1298
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parents:
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1299 #endif // !PRODUCT