1 /*
2 * Copyright (c) 2011, 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 "classfile/vmSymbols.hpp"
28 #include "oops/objArrayOop.inline.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "runtime/java.hpp"
31 #include "runtime/javaCalls.hpp"
32 #include "runtime/mutex.hpp"
33 #include "runtime/mutexLocker.hpp"
34 #include "services/gcNotifier.hpp"
35 #include "services/management.hpp"
36 #include "services/memoryService.hpp"
37 #include "memoryManager.hpp"
38 #include "memory/oopFactory.hpp"
39 #include "memory/resourceArea.hpp"
40
41 GCNotificationRequest *GCNotifier::first_request = NULL;
42 GCNotificationRequest *GCNotifier::last_request = NULL;
43
44 void GCNotifier::pushNotification(GCMemoryManager *mgr, const char *action, const char *cause) {
45 // Make a copy of the last GC statistics
46 // GC may occur between now and the creation of the notification
47 int num_pools = MemoryService::num_memory_pools();
48 // stat is deallocated inside GCNotificationRequest
49 GCStatInfo* stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(num_pools);
50 mgr->get_last_gc_stat(stat);
51 GCNotificationRequest *request = new GCNotificationRequest(os::javaTimeMillis(),mgr,action,cause,stat);
52 addRequest(request);
53 }
54
55 void GCNotifier::addRequest(GCNotificationRequest *request) {
56 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
57 if(first_request == NULL) {
58 first_request = request;
59 } else {
60 last_request->next = request;
61 }
62 last_request = request;
63 Service_lock->notify_all();
64 }
65
66 GCNotificationRequest *GCNotifier::getRequest() {
67 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
68 GCNotificationRequest *request = first_request;
69 if(first_request != NULL) {
70 first_request = first_request->next;
71 }
72 return request;
73 }
74
75 bool GCNotifier::has_event() {
76 return first_request != NULL;
77 }
78
79 static Handle getGcInfoBuilder(GCMemoryManager *gcManager,TRAPS) {
80
81 Klass* gcMBeanKlass = Management::com_sun_management_internal_GarbageCollectorExtImpl_klass(CHECK_NH);
82
83 instanceOop i = gcManager->get_memory_manager_instance(THREAD);
84 instanceHandle ih(THREAD, i);
85
86 JavaValue result(T_OBJECT);
87 JavaCallArguments args(ih);
88
89 JavaCalls::call_virtual(&result,
90 gcMBeanKlass,
91 vmSymbols::getGcInfoBuilder_name(),
92 vmSymbols::getGcInfoBuilder_signature(),
93 &args,
94 CHECK_NH);
95 return Handle(THREAD,(oop)result.get_jobject());
96 }
97
98 static Handle createGcInfo(GCMemoryManager *gcManager, GCStatInfo *gcStatInfo,TRAPS) {
99
100 // Fill the arrays of MemoryUsage objects with before and after GC
101 // per pool memory usage
102
103 InstanceKlass* mu_klass = Management::java_lang_management_MemoryUsage_klass(CHECK_NH);
104
105 // The array allocations below should use a handle containing mu_klass
106 // as the first allocation could trigger a GC, causing the actual
107 // klass oop to move, and leaving mu_klass pointing to the old
108 // location.
109 objArrayOop bu = oopFactory::new_objArray(mu_klass, MemoryService::num_memory_pools(), CHECK_NH);
110 objArrayHandle usage_before_gc_ah(THREAD, bu);
111 objArrayOop au = oopFactory::new_objArray(mu_klass, MemoryService::num_memory_pools(), CHECK_NH);
112 objArrayHandle usage_after_gc_ah(THREAD, au);
113
114 for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
115 Handle before_usage = MemoryService::create_MemoryUsage_obj(gcStatInfo->before_gc_usage_for_pool(i), CHECK_NH);
116 Handle after_usage;
117
118 MemoryUsage u = gcStatInfo->after_gc_usage_for_pool(i);
119 if (u.max_size() == 0 && u.used() > 0) {
120 // If max size == 0, this pool is a survivor space.
121 // Set max size = -1 since the pools will be swapped after GC.
122 MemoryUsage usage(u.init_size(), u.used(), u.committed(), (size_t)-1);
123 after_usage = MemoryService::create_MemoryUsage_obj(usage, CHECK_NH);
124 } else {
125 after_usage = MemoryService::create_MemoryUsage_obj(u, CHECK_NH);
126 }
127 usage_before_gc_ah->obj_at_put(i, before_usage());
128 usage_after_gc_ah->obj_at_put(i, after_usage());
129 }
130
131 // Current implementation only has 1 attribute (number of GC threads)
132 // The type is 'I'
133 objArrayOop extra_args_array = oopFactory::new_objArray(SystemDictionary::Integer_klass(), 1, CHECK_NH);
134 objArrayHandle extra_array (THREAD, extra_args_array);
135 InstanceKlass* intK = SystemDictionary::Integer_klass();
136
137 instanceHandle extra_arg_val = intK->allocate_instance_handle(CHECK_NH);
138
139 {
140 JavaValue res(T_VOID);
141 JavaCallArguments argsInt;
142 argsInt.push_oop(extra_arg_val);
143 argsInt.push_int(gcManager->num_gc_threads());
144
145 JavaCalls::call_special(&res,
146 intK,
147 vmSymbols::object_initializer_name(),
148 vmSymbols::int_void_signature(),
149 &argsInt,
150 CHECK_NH);
151 }
152 extra_array->obj_at_put(0,extra_arg_val());
153
154 InstanceKlass* gcInfoklass = Management::com_sun_management_GcInfo_klass(CHECK_NH);
155
156 Handle gcInfo_instance = gcInfoklass->allocate_instance_handle(CHECK_NH);
157
158 JavaValue constructor_result(T_VOID);
159 JavaCallArguments constructor_args(16);
160 constructor_args.push_oop(gcInfo_instance);
161 constructor_args.push_oop(getGcInfoBuilder(gcManager,THREAD));
162 constructor_args.push_long(gcStatInfo->gc_index());
163 constructor_args.push_long(Management::ticks_to_ms(gcStatInfo->start_time()));
164 constructor_args.push_long(Management::ticks_to_ms(gcStatInfo->end_time()));
165 constructor_args.push_oop(usage_before_gc_ah);
166 constructor_args.push_oop(usage_after_gc_ah);
167 constructor_args.push_oop(extra_array);
168
169 JavaCalls::call_special(&constructor_result,
170 gcInfoklass,
171 vmSymbols::object_initializer_name(),
172 vmSymbols::com_sun_management_GcInfo_constructor_signature(),
173 &constructor_args,
174 CHECK_NH);
175
176 return Handle(THREAD, gcInfo_instance());
177 }
178
179 void GCNotifier::sendNotification(TRAPS) {
180 GCNotifier::sendNotificationInternal(THREAD);
181 // Clearing pending exception to avoid premature termination of
182 // the service thread
183 if (HAS_PENDING_EXCEPTION) {
184 CLEAR_PENDING_EXCEPTION;
185 }
186 }
187
188 class NotificationMark : public StackObj {
189 // This class is used in GCNotifier::sendNotificationInternal to ensure that
190 // the GCNotificationRequest object is properly cleaned up, whatever path
191 // is used to exit the method.
192 GCNotificationRequest* _request;
193 public:
194 NotificationMark(GCNotificationRequest* r) {
195 _request = r;
196 }
197 ~NotificationMark() {
198 assert(_request != NULL, "Sanity check");
199 delete _request;
200 }
201 };
202
203 void GCNotifier::sendNotificationInternal(TRAPS) {
204 ResourceMark rm(THREAD);
205 HandleMark hm(THREAD);
206 GCNotificationRequest *request = getRequest();
207 if (request != NULL) {
208 NotificationMark nm(request);
209 Handle objGcInfo = createGcInfo(request->gcManager, request->gcStatInfo, CHECK);
210
211 Handle objName = java_lang_String::create_from_str(request->gcManager->name(), CHECK);
212 Handle objAction = java_lang_String::create_from_str(request->gcAction, CHECK);
213 Handle objCause = java_lang_String::create_from_str(request->gcCause, CHECK);
214 InstanceKlass* gc_mbean_klass = Management::com_sun_management_internal_GarbageCollectorExtImpl_klass(CHECK);
215
216 instanceOop gc_mbean = request->gcManager->get_memory_manager_instance(THREAD);
217 instanceHandle gc_mbean_h(THREAD, gc_mbean);
218 if (!gc_mbean_h->is_a(gc_mbean_klass)) {
219 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
220 "This GCMemoryManager doesn't have a GarbageCollectorMXBean");
221 }
222
223 JavaValue result(T_VOID);
224 JavaCallArguments args(gc_mbean_h);
225 args.push_long(request->timestamp);
226 args.push_oop(objName);
227 args.push_oop(objAction);
228 args.push_oop(objCause);
229 args.push_oop(objGcInfo);
230
231 JavaCalls::call_virtual(&result,
232 gc_mbean_klass,
233 vmSymbols::createGCNotification_name(),
234 vmSymbols::createGCNotification_signature(),
235 &args,
236 CHECK);
237 }
238 }
239