1 /* 2 * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "classfile/systemDictionary.hpp" 27 #include "classfile/vmSymbols.hpp" 28 #include "memory/allocation.inline.hpp" 29 #include "memory/resourceArea.hpp" 30 #include "oops/oop.inline.hpp" 31 #include "runtime/arguments.hpp" 32 #include "runtime/java.hpp" 33 #include "runtime/javaCalls.hpp" 34 #include "runtime/os.hpp" 35 #include "runtime/statSampler.hpp" 36 #include "runtime/vm_version.hpp" 37 38 // -------------------------------------------------------- 39 // StatSamplerTask 40 41 class StatSamplerTask : public PeriodicTask { 42 public: 43 StatSamplerTask(int interval_time) : PeriodicTask(interval_time) {} 44 void task() { StatSampler::collect_sample(); } 45 }; 46 47 48 //---------------------------------------------------------- 49 // Implementation of StatSampler 50 51 StatSamplerTask* StatSampler::_task = NULL; 52 PerfDataList* StatSampler::_sampled = NULL; 53 54 /* 55 * the initialize method is called from the engage() method 56 * and is responsible for initializing various global variables. 57 */ 58 void StatSampler::initialize() { 59 60 if (!UsePerfData) return; 61 62 // create performance data that could not be created prior 63 // to vm_init_globals() or otherwise have no logical home. 64 65 create_misc_perfdata(); 66 67 // get copy of the sampled list 68 _sampled = PerfDataManager::sampled(); 69 70 } 71 72 /* 73 * The engage() method is called at initialization time via 74 * Thread::create_vm() to initialize the StatSampler and 75 * register it with the WatcherThread as a periodic task. 76 */ 77 void StatSampler::engage() { 78 79 if (!UsePerfData) return; 80 81 if (!is_active()) { 82 83 initialize(); 84 85 // start up the periodic task 86 _task = new StatSamplerTask(PerfDataSamplingInterval); 87 _task->enroll(); 88 } 89 } 90 91 92 /* 93 * the disengage() method is responsible for deactivating the periodic 94 * task and, if logging was enabled, for logging the final sample. This 95 * method is called from before_exit() in java.cpp and is only called 96 * after the WatcherThread has been stopped. 97 */ 98 void StatSampler::disengage() { 99 100 if (!UsePerfData) return; 101 102 if (!is_active()) 103 return; 104 105 // remove StatSamplerTask 106 _task->disenroll(); 107 delete _task; 108 _task = NULL; 109 110 // force a final sample 111 sample_data(_sampled); 112 } 113 114 /* 115 * the destroy method is responsible for releasing any resources used by 116 * the StatSampler prior to shutdown of the VM. this method is called from 117 * before_exit() in java.cpp and is only called after the WatcherThread 118 * has stopped. 119 */ 120 void StatSampler::destroy() { 121 122 if (!UsePerfData) return; 123 124 if (_sampled != NULL) { 125 delete(_sampled); 126 _sampled = NULL; 127 } 128 } 129 130 /* 131 * The sample_data() method is responsible for sampling the 132 * the data value for each PerfData instance in the given list. 133 */ 134 void StatSampler::sample_data(PerfDataList* list) { 135 136 assert(list != NULL, "null list unexpected"); 137 138 for (int index = 0; index < list->length(); index++) { 139 PerfData* item = list->at(index); 140 item->sample(); 141 } 142 } 143 144 /* 145 * the collect_sample() method is the method invoked by the 146 * WatcherThread via the PeriodicTask::task() method. This method 147 * is responsible for collecting data samples from sampled 148 * PerfData instances every PerfDataSamplingInterval milliseconds. 149 * It is also responsible for logging the requested set of 150 * PerfData instances every _sample_count milliseconds. While 151 * logging data, it will output a column header after every _print_header 152 * rows of data have been logged. 153 */ 154 void StatSampler::collect_sample() { 155 156 // future - check for new PerfData objects. PerfData objects might 157 // get added to the PerfDataManager lists after we have already 158 // built our local copies. 159 // 160 // if (PerfDataManager::count() > previous) { 161 // // get a new copy of the sampled list 162 // if (_sampled != NULL) { 163 // delete(_sampled); 164 // _sampled = NULL; 165 // } 166 // _sampled = PerfDataManager::sampled(); 167 // } 168 169 assert(_sampled != NULL, "list not initialized"); 170 171 sample_data(_sampled); 172 } 173 174 /* 175 * method to upcall into Java to return the value of the specified 176 * property as a utf8 string, or NULL if does not exist. The caller 177 * is responsible for setting a ResourceMark for proper cleanup of 178 * the utf8 strings. 179 */ 180 const char* StatSampler::get_system_property(const char* name, TRAPS) { 181 182 // setup the arguments to getProperty 183 Handle key_str = java_lang_String::create_from_str(name, CHECK_NULL); 184 185 // return value 186 JavaValue result(T_OBJECT); 187 188 // public static String getProperty(String key, String def); 189 JavaCalls::call_static(&result, 190 KlassHandle(THREAD, SystemDictionary::System_klass()), 191 vmSymbols::getProperty_name(), 192 vmSymbols::string_string_signature(), 193 key_str, 194 CHECK_NULL); 195 196 oop value_oop = (oop)result.get_jobject(); 197 if (value_oop == NULL) { 198 return NULL; 199 } 200 201 // convert Java String to utf8 string 202 char* value = java_lang_String::as_utf8_string(value_oop); 203 204 return value; 205 } 206 207 /* 208 * The list of System Properties that have corresponding PerfData 209 * string instrumentation created by retrieving the named property's 210 * value from System.getProperty() and unconditionally creating a 211 * PerfStringConstant object initialized to the retrieved value. This 212 * is not an exhaustive list of Java properties with corresponding string 213 * instrumentation as the create_system_property_instrumentation() method 214 * creates other property based instrumentation conditionally. 215 */ 216 217 // stable interface, supported counters 218 static const char* property_counters_ss[] = { 219 "java.vm.specification.version", 220 "java.vm.specification.name", 221 "java.vm.specification.vendor", 222 "java.vm.version", 223 "java.vm.name", 224 "java.vm.vendor", 225 "java.vm.info", 226 "java.library.path", 227 "java.class.path", 228 "java.endorsed.dirs", 229 "java.ext.dirs", 230 "java.version", 231 "java.home", 232 NULL 233 }; 234 235 // unstable interface, supported counters 236 static const char* property_counters_us[] = { 237 NULL 238 }; 239 240 // unstable interface, unsupported counters 241 static const char* property_counters_uu[] = { 242 "sun.boot.class.path", 243 "sun.boot.library.path", 244 NULL 245 }; 246 247 typedef struct { 248 const char** property_list; 249 CounterNS name_space; 250 } PropertyCounters; 251 252 static PropertyCounters property_counters[] = { 253 { property_counters_ss, JAVA_PROPERTY }, 254 { property_counters_us, COM_PROPERTY }, 255 { property_counters_uu, SUN_PROPERTY }, 256 { NULL, SUN_PROPERTY } 257 }; 258 259 260 /* 261 * Method to create PerfData string instruments that contain the values 262 * of various system properties. String instruments are created for each 263 * property specified in the property lists provided in property_counters[]. 264 * Property counters have a counter name space prefix prepended to the 265 * property name as indicated in property_counters[]. 266 */ 267 void StatSampler::create_system_property_instrumentation(TRAPS) { 268 269 ResourceMark rm; 270 271 for (int i = 0; property_counters[i].property_list != NULL; i++) { 272 273 for (int j = 0; property_counters[i].property_list[j] != NULL; j++) { 274 275 const char* property_name = property_counters[i].property_list[j]; 276 assert(property_name != NULL, "property name should not be NULL"); 277 278 const char* value = get_system_property(property_name, CHECK); 279 280 // the property must exist 281 assert(value != NULL, "property name should be valid"); 282 283 if (value != NULL) { 284 // create the property counter 285 PerfDataManager::create_string_constant(property_counters[i].name_space, 286 property_name, value, CHECK); 287 } 288 } 289 } 290 } 291 292 /* 293 * The create_misc_perfdata() method provides a place to create 294 * PerfData instances that would otherwise have no better place 295 * to exist. 296 */ 297 void StatSampler::create_misc_perfdata() { 298 299 ResourceMark rm; 300 EXCEPTION_MARK; 301 302 // numeric constants 303 304 // frequency of the native high resolution timer 305 PerfDataManager::create_constant(SUN_OS, "hrt.frequency", 306 PerfData::U_Hertz, os::elapsed_frequency(), 307 CHECK); 308 309 // string constants 310 311 // create string instrumentation for various Java properties. 312 create_system_property_instrumentation(CHECK); 313 314 // HotSpot flags (from .hotspotrc) and args (from command line) 315 // 316 PerfDataManager::create_string_constant(JAVA_RT, "vmFlags", 317 Arguments::jvm_flags(), CHECK); 318 PerfDataManager::create_string_constant(JAVA_RT, "vmArgs", 319 Arguments::jvm_args(), CHECK); 320 321 // java class name/jar file and arguments to main class 322 // note: name is cooridnated with launcher and Arguments.cpp 323 PerfDataManager::create_string_constant(SUN_RT, "javaCommand", 324 Arguments::java_command(), CHECK); 325 326 // the Java VM Internal version string 327 PerfDataManager::create_string_constant(SUN_RT, "internalVersion", 328 VM_Version::internal_vm_info_string(), 329 CHECK); 330 331 // create sampled instrumentation objects 332 create_sampled_perfdata(); 333 } 334 335 /* 336 * helper class to provide for sampling of the elapsed_counter value 337 * maintained in the OS class. 338 */ 339 class HighResTimeSampler : public PerfSampleHelper { 340 public: 341 jlong take_sample() { return os::elapsed_counter(); } 342 }; 343 344 /* 345 * the create_sampled_perdata() method provides a place to instantiate 346 * sampled PerfData instances that would otherwise have no better place 347 * to exist. 348 */ 349 void StatSampler::create_sampled_perfdata() { 350 351 EXCEPTION_MARK; 352 353 // setup sampling of the elapsed time counter maintained in the 354 // the os class. This counter can be used as either a time stamp 355 // for each logged entry or as a liveness indicator for the VM. 356 PerfSampleHelper* psh = new HighResTimeSampler(); 357 PerfDataManager::create_counter(SUN_OS, "hrt.ticks", 358 PerfData::U_Ticks, psh, CHECK); 359 } 360 361 /* 362 * the statSampler_exit() function is called from os_init.cpp on 363 * exit of the vm. 364 */ 365 void statSampler_exit() { 366 367 if (!UsePerfData) return; 368 369 StatSampler::destroy(); 370 }