/* * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "classfile/systemDictionary.hpp" #include "classfile/vmSymbols.hpp" #include "memory/allocation.inline.hpp" #include "memory/resourceArea.hpp" #include "oops/oop.inline.hpp" #include "runtime/arguments.hpp" #include "runtime/java.hpp" #include "runtime/javaCalls.hpp" #include "runtime/os.hpp" #include "runtime/statSampler.hpp" #include "runtime/vm_version.hpp" // -------------------------------------------------------- // StatSamplerTask class StatSamplerTask : public PeriodicTask { public: StatSamplerTask(int interval_time) : PeriodicTask(interval_time) {} void task() { StatSampler::collect_sample(); } }; //---------------------------------------------------------- // Implementation of StatSampler StatSamplerTask* StatSampler::_task = NULL; PerfDataList* StatSampler::_sampled = NULL; /* * the initialize method is called from the engage() method * and is responsible for initializing various global variables. */ void StatSampler::initialize() { if (!UsePerfData) return; // create performance data that could not be created prior // to vm_init_globals() or otherwise have no logical home. create_misc_perfdata(); // get copy of the sampled list _sampled = PerfDataManager::sampled(); } /* * The engage() method is called at initialization time via * Thread::create_vm() to initialize the StatSampler and * register it with the WatcherThread as a periodic task. */ void StatSampler::engage() { if (!UsePerfData) return; if (!is_active()) { initialize(); // start up the periodic task _task = new StatSamplerTask(PerfDataSamplingInterval); _task->enroll(); } } /* * the disengage() method is responsible for deactivating the periodic * task and, if logging was enabled, for logging the final sample. This * method is called from before_exit() in java.cpp and is only called * after the WatcherThread has been stopped. */ void StatSampler::disengage() { if (!UsePerfData) return; if (!is_active()) return; // remove StatSamplerTask _task->disenroll(); delete _task; _task = NULL; // force a final sample sample_data(_sampled); } /* * the destroy method is responsible for releasing any resources used by * the StatSampler prior to shutdown of the VM. this method is called from * before_exit() in java.cpp and is only called after the WatcherThread * has stopped. */ void StatSampler::destroy() { if (!UsePerfData) return; if (_sampled != NULL) { delete(_sampled); _sampled = NULL; } } /* * The sample_data() method is responsible for sampling the * the data value for each PerfData instance in the given list. */ void StatSampler::sample_data(PerfDataList* list) { assert(list != NULL, "null list unexpected"); for (int index = 0; index < list->length(); index++) { PerfData* item = list->at(index); item->sample(); } } /* * the collect_sample() method is the method invoked by the * WatcherThread via the PeriodicTask::task() method. This method * is responsible for collecting data samples from sampled * PerfData instances every PerfDataSamplingInterval milliseconds. * It is also responsible for logging the requested set of * PerfData instances every _sample_count milliseconds. While * logging data, it will output a column header after every _print_header * rows of data have been logged. */ void StatSampler::collect_sample() { // future - check for new PerfData objects. PerfData objects might // get added to the PerfDataManager lists after we have already // built our local copies. // // if (PerfDataManager::count() > previous) { // // get a new copy of the sampled list // if (_sampled != NULL) { // delete(_sampled); // _sampled = NULL; // } // _sampled = PerfDataManager::sampled(); // } assert(_sampled != NULL, "list not initialized"); sample_data(_sampled); } /* * method to upcall into Java to return the value of the specified * property as a utf8 string, or NULL if does not exist. The caller * is responsible for setting a ResourceMark for proper cleanup of * the utf8 strings. */ const char* StatSampler::get_system_property(const char* name, TRAPS) { // setup the arguments to getProperty Handle key_str = java_lang_String::create_from_str(name, CHECK_NULL); // return value JavaValue result(T_OBJECT); // public static String getProperty(String key, String def); JavaCalls::call_static(&result, KlassHandle(THREAD, SystemDictionary::System_klass()), vmSymbols::getProperty_name(), vmSymbols::string_string_signature(), key_str, CHECK_NULL); oop value_oop = (oop)result.get_jobject(); if (value_oop == NULL) { return NULL; } // convert Java String to utf8 string char* value = java_lang_String::as_utf8_string(value_oop); return value; } /* * The list of System Properties that have corresponding PerfData * string instrumentation created by retrieving the named property's * value from System.getProperty() and unconditionally creating a * PerfStringConstant object initialized to the retrieved value. This * is not an exhaustive list of Java properties with corresponding string * instrumentation as the create_system_property_instrumentation() method * creates other property based instrumentation conditionally. */ // stable interface, supported counters static const char* property_counters_ss[] = { "java.vm.specification.version", "java.vm.specification.name", "java.vm.specification.vendor", "java.vm.version", "java.vm.name", "java.vm.vendor", "java.vm.info", "java.library.path", "java.class.path", "java.endorsed.dirs", "java.ext.dirs", "java.version", "java.home", NULL }; // unstable interface, supported counters static const char* property_counters_us[] = { NULL }; // unstable interface, unsupported counters static const char* property_counters_uu[] = { "sun.boot.class.path", "sun.boot.library.path", NULL }; typedef struct { const char** property_list; CounterNS name_space; } PropertyCounters; static PropertyCounters property_counters[] = { { property_counters_ss, JAVA_PROPERTY }, { property_counters_us, COM_PROPERTY }, { property_counters_uu, SUN_PROPERTY }, { NULL, SUN_PROPERTY } }; /* * Method to create PerfData string instruments that contain the values * of various system properties. String instruments are created for each * property specified in the property lists provided in property_counters[]. * Property counters have a counter name space prefix prepended to the * property name as indicated in property_counters[]. */ void StatSampler::create_system_property_instrumentation(TRAPS) { ResourceMark rm; for (int i = 0; property_counters[i].property_list != NULL; i++) { for (int j = 0; property_counters[i].property_list[j] != NULL; j++) { const char* property_name = property_counters[i].property_list[j]; assert(property_name != NULL, "property name should not be NULL"); const char* value = get_system_property(property_name, CHECK); // the property must exist assert(value != NULL, "property name should be valid"); if (value != NULL) { // create the property counter PerfDataManager::create_string_constant(property_counters[i].name_space, property_name, value, CHECK); } } } } /* * The create_misc_perfdata() method provides a place to create * PerfData instances that would otherwise have no better place * to exist. */ void StatSampler::create_misc_perfdata() { ResourceMark rm; EXCEPTION_MARK; // numeric constants // frequency of the native high resolution timer PerfDataManager::create_constant(SUN_OS, "hrt.frequency", PerfData::U_Hertz, os::elapsed_frequency(), CHECK); // string constants // create string instrumentation for various Java properties. create_system_property_instrumentation(CHECK); // HotSpot flags (from .hotspotrc) and args (from command line) // PerfDataManager::create_string_constant(JAVA_RT, "vmFlags", Arguments::jvm_flags(), CHECK); PerfDataManager::create_string_constant(JAVA_RT, "vmArgs", Arguments::jvm_args(), CHECK); // java class name/jar file and arguments to main class // note: name is cooridnated with launcher and Arguments.cpp PerfDataManager::create_string_constant(SUN_RT, "javaCommand", Arguments::java_command(), CHECK); // the Java VM Internal version string PerfDataManager::create_string_constant(SUN_RT, "internalVersion", VM_Version::internal_vm_info_string(), CHECK); // create sampled instrumentation objects create_sampled_perfdata(); } /* * helper class to provide for sampling of the elapsed_counter value * maintained in the OS class. */ class HighResTimeSampler : public PerfSampleHelper { public: jlong take_sample() { return os::elapsed_counter(); } }; /* * the create_sampled_perdata() method provides a place to instantiate * sampled PerfData instances that would otherwise have no better place * to exist. */ void StatSampler::create_sampled_perfdata() { EXCEPTION_MARK; // setup sampling of the elapsed time counter maintained in the // the os class. This counter can be used as either a time stamp // for each logged entry or as a liveness indicator for the VM. PerfSampleHelper* psh = new HighResTimeSampler(); PerfDataManager::create_counter(SUN_OS, "hrt.ticks", PerfData::U_Ticks, psh, CHECK); } /* * the statSampler_exit() function is called from os_init.cpp on * exit of the vm. */ void statSampler_exit() { if (!UsePerfData) return; StatSampler::destroy(); }