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/instanceKlass.inline.hpp"
29 #include "oops/objArrayOop.inline.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "runtime/interfaceSupport.hpp"
32 #include "runtime/java.hpp"
33 #include "runtime/javaCalls.hpp"
34 #include "runtime/mutex.hpp"
35 #include "runtime/mutexLocker.hpp"
36 #include "services/gcNotifier.hpp"
37 #include "services/management.hpp"
38 #include "services/memoryService.hpp"
39 #include "memoryManager.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "memory/resourceArea.hpp"
42
43 GCNotificationRequest *GCNotifier::first_request = NULL;
44 GCNotificationRequest *GCNotifier::last_request = NULL;
45
46 void GCNotifier::pushNotification(GCMemoryManager *mgr, const char *action, const char *cause) {
47 // Make a copy of the last GC statistics
48 // GC may occur between now and the creation of the notification
49 int num_pools = MemoryService::num_memory_pools();
50 // stat is deallocated inside GCNotificationRequest
51 GCStatInfo* stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(num_pools);
52 mgr->get_last_gc_stat(stat);
53 GCNotificationRequest *request = new GCNotificationRequest(os::javaTimeMillis(),mgr,action,cause,stat);
54 addRequest(request);
55 }
56
57 void GCNotifier::addRequest(GCNotificationRequest *request) {
58 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
59 if(first_request == NULL) {
60 first_request = request;
61 } else {
62 last_request->next = request;
63 }
64 last_request = request;
65 Service_lock->notify_all();
66 }
67
68 GCNotificationRequest *GCNotifier::getRequest() {
69 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
70 GCNotificationRequest *request = first_request;
71 if(first_request != NULL) {
72 first_request = first_request->next;
73 }
74 return request;
75 }
76
77 bool GCNotifier::has_event() {
78 return first_request != NULL;
79 }
80
81 static Handle getGcInfoBuilder(GCMemoryManager *gcManager,TRAPS) {
82
83 Klass* gcMBeanKlass = Management::com_sun_management_internal_GarbageCollectorExtImpl_klass(CHECK_NH);
84
85 instanceOop i = gcManager->get_memory_manager_instance(THREAD);
86 instanceHandle ih(THREAD, i);
87
88 JavaValue result(T_OBJECT);
89 JavaCallArguments args(ih);
90
91 JavaCalls::call_virtual(&result,
92 gcMBeanKlass,
93 vmSymbols::getGcInfoBuilder_name(),
94 vmSymbols::getGcInfoBuilder_signature(),
95 &args,
96 CHECK_NH);
97 return Handle(THREAD,(oop)result.get_jobject());
98 }
99
100 static Handle createGcInfo(GCMemoryManager *gcManager, GCStatInfo *gcStatInfo,TRAPS) {
101
102 // Fill the arrays of MemoryUsage objects with before and after GC
103 // per pool memory usage
104
105 InstanceKlass* mu_klass = Management::java_lang_management_MemoryUsage_klass(CHECK_NH);
106
107 // The array allocations below should use a handle containing mu_klass
108 // as the first allocation could trigger a GC, causing the actual
109 // klass oop to move, and leaving mu_klass pointing to the old
110 // location.
111 objArrayOop bu = oopFactory::new_objArray(mu_klass, MemoryService::num_memory_pools(), CHECK_NH);
112 objArrayHandle usage_before_gc_ah(THREAD, bu);
113 objArrayOop au = oopFactory::new_objArray(mu_klass, MemoryService::num_memory_pools(), CHECK_NH);
114 objArrayHandle usage_after_gc_ah(THREAD, au);
115
116 for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
117 Handle before_usage = MemoryService::create_MemoryUsage_obj(gcStatInfo->before_gc_usage_for_pool(i), CHECK_NH);
118 Handle after_usage;
119
120 MemoryUsage u = gcStatInfo->after_gc_usage_for_pool(i);
121 if (u.max_size() == 0 && u.used() > 0) {
122 // If max size == 0, this pool is a survivor space.
123 // Set max size = -1 since the pools will be swapped after GC.
124 MemoryUsage usage(u.init_size(), u.used(), u.committed(), (size_t)-1);
125 after_usage = MemoryService::create_MemoryUsage_obj(usage, CHECK_NH);
126 } else {
127 after_usage = MemoryService::create_MemoryUsage_obj(u, CHECK_NH);
128 }
129 usage_before_gc_ah->obj_at_put(i, before_usage());
130 usage_after_gc_ah->obj_at_put(i, after_usage());
131 }
132
133 // Current implementation only has 1 attribute (number of GC threads)
134 // The type is 'I'
135 objArrayOop extra_args_array = oopFactory::new_objArray(SystemDictionary::Integer_klass(), 1, CHECK_NH);
136 objArrayHandle extra_array (THREAD, extra_args_array);
137 InstanceKlass* intK = SystemDictionary::Integer_klass();
138
139 instanceHandle extra_arg_val = intK->allocate_instance_handle(CHECK_NH);
140
141 {
142 JavaValue res(T_VOID);
143 JavaCallArguments argsInt;
144 argsInt.push_oop(extra_arg_val);
145 argsInt.push_int(gcManager->num_gc_threads());
146
147 JavaCalls::call_special(&res,
148 intK,
149 vmSymbols::object_initializer_name(),
150 vmSymbols::int_void_signature(),
151 &argsInt,
152 CHECK_NH);
153 }
154 extra_array->obj_at_put(0,extra_arg_val());
155
156 InstanceKlass* gcInfoklass = Management::com_sun_management_GcInfo_klass(CHECK_NH);
157
158 Handle gcInfo_instance = gcInfoklass->allocate_instance_handle(CHECK_NH);
159
160 JavaValue constructor_result(T_VOID);
161 JavaCallArguments constructor_args(16);
162 constructor_args.push_oop(gcInfo_instance);
163 constructor_args.push_oop(getGcInfoBuilder(gcManager,THREAD));
164 constructor_args.push_long(gcStatInfo->gc_index());
165 constructor_args.push_long(Management::ticks_to_ms(gcStatInfo->start_time()));
166 constructor_args.push_long(Management::ticks_to_ms(gcStatInfo->end_time()));
167 constructor_args.push_oop(usage_before_gc_ah);
168 constructor_args.push_oop(usage_after_gc_ah);
169 constructor_args.push_oop(extra_array);
170
171 JavaCalls::call_special(&constructor_result,
172 gcInfoklass,
173 vmSymbols::object_initializer_name(),
174 vmSymbols::com_sun_management_GcInfo_constructor_signature(),
175 &constructor_args,
176 CHECK_NH);
177
178 return Handle(THREAD, gcInfo_instance());
179 }
180
181 void GCNotifier::sendNotification(TRAPS) {
182 GCNotifier::sendNotificationInternal(THREAD);
183 // Clearing pending exception to avoid premature termination of
184 // the service thread
185 if (HAS_PENDING_EXCEPTION) {
186 CLEAR_PENDING_EXCEPTION;
187 }
188 }
189
190 class NotificationMark : public StackObj {
191 // This class is used in GCNotifier::sendNotificationInternal to ensure that
192 // the GCNotificationRequest object is properly cleaned up, whatever path
193 // is used to exit the method.
194 GCNotificationRequest* _request;
195 public:
196 NotificationMark(GCNotificationRequest* r) {
197 _request = r;
198 }
199 ~NotificationMark() {
200 assert(_request != NULL, "Sanity check");
201 delete _request;
202 }
203 };
204
205 void GCNotifier::sendNotificationInternal(TRAPS) {
206 ResourceMark rm(THREAD);
207 HandleMark hm(THREAD);
208 GCNotificationRequest *request = getRequest();
209 if (request != NULL) {
210 NotificationMark nm(request);
211 Handle objGcInfo = createGcInfo(request->gcManager, request->gcStatInfo, CHECK);
212
213 Handle objName = java_lang_String::create_from_str(request->gcManager->name(), CHECK);
214 Handle objAction = java_lang_String::create_from_str(request->gcAction, CHECK);
215 Handle objCause = java_lang_String::create_from_str(request->gcCause, CHECK);
216 InstanceKlass* gc_mbean_klass = Management::com_sun_management_internal_GarbageCollectorExtImpl_klass(CHECK);
217
218 instanceOop gc_mbean = request->gcManager->get_memory_manager_instance(THREAD);
219 instanceHandle gc_mbean_h(THREAD, gc_mbean);
220 if (!gc_mbean_h->is_a(gc_mbean_klass)) {
221 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
222 "This GCMemoryManager doesn't have a GarbageCollectorMXBean");
223 }
224
225 JavaValue result(T_VOID);
226 JavaCallArguments args(gc_mbean_h);
227 args.push_long(request->timestamp);
228 args.push_oop(objName);
229 args.push_oop(objAction);
230 args.push_oop(objCause);
231 args.push_oop(objGcInfo);
232
233 JavaCalls::call_virtual(&result,
234 gc_mbean_klass,
235 vmSymbols::createGCNotification_name(),
236 vmSymbols::createGCNotification_signature(),
237 &args,
238 CHECK);
239 }
240 }
241