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