1 /*

     2  * Copyright (c) 2003, 2017, 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 "memory/allocation.hpp"

    28 #include "memory/resourceArea.hpp"

    29 #include "memory/universe.hpp"

    30 #include "oops/oop.inline.hpp"

    31 #include "runtime/mutexLocker.hpp"

    32 #include "services/classLoadingService.hpp"

    33 #include "services/memoryService.hpp"

    34 #include "utilities/dtrace.hpp"

    35 #include "utilities/macros.hpp"

    36 #include "utilities/defaultStream.hpp"

    37 #include "logging/log.hpp"

    38 #include "logging/logConfiguration.hpp"

    39 

    40 #ifdef DTRACE_ENABLED

    41 

    42 // Only bother with this argument setup if dtrace is available

    43 

    44 #define HOTSPOT_CLASS_unloaded HOTSPOT_CLASS_UNLOADED

    45 #define HOTSPOT_CLASS_loaded HOTSPOT_CLASS_LOADED

    46 #define DTRACE_CLASSLOAD_PROBE(type, clss, shared)  \

    47   {                                                 \

    48     char* data = NULL;                              \

    49     int len = 0;                                    \

    50     Symbol* name = (clss)->name();                  \

    51     if (name != NULL) {                             \

    52       data = (char*)name->bytes();                  \

    53       len = name->utf8_length();                    \

    54     }                                               \

    55     HOTSPOT_CLASS_##type( /* type = unloaded, loaded */ \

    56       data, len, (void*)(clss)->class_loader(), (shared)); \

    57   }

    58 

    59 #else //  ndef DTRACE_ENABLED

    60 

    61 #define DTRACE_CLASSLOAD_PROBE(type, clss, shared)

    62 

    63 #endif

    64 

    65 #if INCLUDE_MANAGEMENT

    66 // counters for classes loaded from class files

    67 PerfCounter*    ClassLoadingService::_classes_loaded_count = NULL;

    68 PerfCounter*    ClassLoadingService::_classes_unloaded_count = NULL;

    69 PerfCounter*    ClassLoadingService::_classbytes_loaded = NULL;

    70 PerfCounter*    ClassLoadingService::_classbytes_unloaded = NULL;

    71 

    72 // counters for classes loaded from shared archive

    73 PerfCounter*    ClassLoadingService::_shared_classes_loaded_count = NULL;

    74 PerfCounter*    ClassLoadingService::_shared_classes_unloaded_count = NULL;

    75 PerfCounter*    ClassLoadingService::_shared_classbytes_loaded = NULL;

    76 PerfCounter*    ClassLoadingService::_shared_classbytes_unloaded = NULL;

    77 PerfVariable*   ClassLoadingService::_class_methods_size = NULL;

    78 

    79 void ClassLoadingService::init() {

    80   EXCEPTION_MARK;

    81 

    82   // These counters are for java.lang.management API support.

    83   // They are created even if -XX:-UsePerfData is set and in

    84   // that case, they will be allocated on C heap.

    85   _classes_loaded_count =

    86                  PerfDataManager::create_counter(JAVA_CLS, "loadedClasses",

    87                                                  PerfData::U_Events, CHECK);

    88 

    89   _classes_unloaded_count =

    90                  PerfDataManager::create_counter(JAVA_CLS, "unloadedClasses",

    91                                                  PerfData::U_Events, CHECK);

    92 

    93   _shared_classes_loaded_count =

    94                  PerfDataManager::create_counter(JAVA_CLS, "sharedLoadedClasses",

    95                                                  PerfData::U_Events, CHECK);

    96 

    97   _shared_classes_unloaded_count =

    98                  PerfDataManager::create_counter(JAVA_CLS, "sharedUnloadedClasses",

    99                                                  PerfData::U_Events, CHECK);

   100 

   101   if (UsePerfData) {

   102     _classbytes_loaded =

   103                  PerfDataManager::create_counter(SUN_CLS, "loadedBytes",

   104                                                  PerfData::U_Bytes, CHECK);

   105 

   106     _classbytes_unloaded =

   107                  PerfDataManager::create_counter(SUN_CLS, "unloadedBytes",

   108                                                  PerfData::U_Bytes, CHECK);

   109     _shared_classbytes_loaded =

   110                  PerfDataManager::create_counter(SUN_CLS, "sharedLoadedBytes",

   111                                                  PerfData::U_Bytes, CHECK);

   112 

   113     _shared_classbytes_unloaded =

   114                  PerfDataManager::create_counter(SUN_CLS, "sharedUnloadedBytes",

   115                                                  PerfData::U_Bytes, CHECK);

   116     _class_methods_size =

   117                  PerfDataManager::create_variable(SUN_CLS, "methodBytes",

   118                                                   PerfData::U_Bytes, CHECK);

   119   }

   120 }

   121 

   122 void ClassLoadingService::notify_class_unloaded(InstanceKlass* k) {

   123   DTRACE_CLASSLOAD_PROBE(unloaded, k, false);

   124   // Classes that can be unloaded must be non-shared

   125   _classes_unloaded_count->inc();

   126 

   127   if (UsePerfData) {

   128     // add the class size

   129     size_t size = compute_class_size(k);

   130     _classbytes_unloaded->inc(size);

   131 

   132     // Compute method size & subtract from running total.

   133     // We are called during phase 1 of mark sweep, so it's

   134     // still ok to iterate through Method*s here.

   135     Array<Method*>* methods = k->methods();

   136     for (int i = 0; i < methods->length(); i++) {

   137       _class_methods_size->inc(-methods->at(i)->size());

   138     }

   139   }

   140 

   141   if (log_is_enabled(Info, class, unload)) {

   142     ResourceMark rm;

   143     log_info(class, unload)("unloading class %s " INTPTR_FORMAT , k->external_name(), p2i(k));

   144   }

   145 }

   146 

   147 void ClassLoadingService::notify_class_loaded(InstanceKlass* k, bool shared_class) {

   148   DTRACE_CLASSLOAD_PROBE(loaded, k, shared_class);

   149   PerfCounter* classes_counter = (shared_class ? _shared_classes_loaded_count

   150                                                : _classes_loaded_count);

   151   // increment the count

   152   classes_counter->inc();

   153 

   154   if (UsePerfData) {

   155     PerfCounter* classbytes_counter = (shared_class ? _shared_classbytes_loaded

   156                                                     : _classbytes_loaded);

   157     // add the class size

   158     size_t size = compute_class_size(k);

   159     classbytes_counter->inc(size);

   160   }

   161 }

   162 

   163 size_t ClassLoadingService::compute_class_size(InstanceKlass* k) {

   164   // lifted from ClassStatistics.do_class(Klass* k)

   165 

   166   size_t class_size = 0;

   167 

   168   class_size += k->size();

   169 

   170   if (k->is_instance_klass()) {

   171     class_size += k->methods()->size();

   172     // FIXME: Need to count the contents of methods

   173     class_size += k->constants()->size();

   174     class_size += k->local_interfaces()->size();

   175     class_size += k->transitive_interfaces()->size();

   176     // We do not have to count implementors, since we only store one!

   177     // FIXME: How should these be accounted for, now when they have moved.

   178     //class_size += k->fields()->size();

   179   }

   180   return class_size * oopSize;

   181 }

   182 

   183 bool ClassLoadingService::set_verbose(bool verbose) {

   184   MutexLocker m(Management_lock);

   185   // verbose will be set to the previous value

   186   LogLevelType level = verbose ? LogLevel::Info : LogLevel::Off;

   187   LogConfiguration::configure_stdout(level, false, LOG_TAGS(class, load));

   188   reset_trace_class_unloading();

   189   return verbose;

   190 }

   191 

   192 // Caller to this function must own Management_lock

   193 void ClassLoadingService::reset_trace_class_unloading() {

   194   assert(Management_lock->owned_by_self(), "Must own the Management_lock");

   195   bool value = MemoryService::get_verbose() || ClassLoadingService::get_verbose();

   196   LogLevelType level = value ? LogLevel::Info : LogLevel::Off;

   197   LogConfiguration::configure_stdout(level, false, LOG_TAGS(class, unload));

   198 }

   199 

   200 #endif // INCLUDE_MANAGEMENT