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 #ifndef SHARE_RUNTIME_SYNCHRONIZER_HPP
26 #define SHARE_RUNTIME_SYNCHRONIZER_HPP
27
28 #include "memory/padded.hpp"
29 #include "oops/markWord.hpp"
30 #include "runtime/basicLock.hpp"
31 #include "runtime/handles.hpp"
32 #include "runtime/perfData.hpp"
33
34 class ObjectMonitor;
35 class ThreadsList;
36
37 typedef PaddedEnd<ObjectMonitor, DEFAULT_CACHE_LINE_SIZE> PaddedObjectMonitor;
38
39 struct DeflateMonitorCounters {
40 int n_in_use; // currently associated with objects
41 int n_in_circulation; // extant
42 int n_scavenged; // reclaimed (global and per-thread)
43 int per_thread_scavenged; // per-thread scavenge total
44 double per_thread_times; // per-thread scavenge times
45 };
46
47 class ObjectSynchronizer : AllStatic {
48 friend class VMStructs;
49 public:
50 typedef enum {
51 owner_self,
52 owner_none,
53 owner_other
54 } LockOwnership;
92 // Handle all interpreter, compiler and jni cases
93 static int wait(Handle obj, jlong millis, TRAPS);
94 static void notify(Handle obj, TRAPS);
95 static void notifyall(Handle obj, TRAPS);
96
97 static bool quick_notify(oopDesc* obj, Thread* self, bool All);
98 static bool quick_enter(oop obj, Thread* self, BasicLock* Lock);
99
100 // Special internal-use-only method for use by JVM infrastructure
101 // that needs to wait() on a java-level object but that can't risk
102 // throwing unexpected InterruptedExecutionExceptions.
103 static void wait_uninterruptibly(Handle obj, jlong Millis, Thread* THREAD);
104
105 // used by classloading to free classloader object lock,
106 // wait on an internal lock, and reclaim original lock
107 // with original recursion count
108 static intptr_t complete_exit(Handle obj, TRAPS);
109 static void reenter (Handle obj, intptr_t recursion, TRAPS);
110
111 // thread-specific and global ObjectMonitor free list accessors
112 static ObjectMonitor* om_alloc(Thread* self);
113 static void om_release(Thread* self, ObjectMonitor* m,
114 bool FromPerThreadAlloc);
115 static void om_flush(Thread* self);
116
117 // Inflate light weight monitor to heavy weight monitor
118 static ObjectMonitor* inflate(Thread* self, oop obj, const InflateCause cause);
119 // This version is only for internal use
120 static void inflate_helper(oop obj);
121 static const char* inflate_cause_name(const InflateCause cause);
122
123 // Returns the identity hash value for an oop
124 // NOTE: It may cause monitor inflation
125 static intptr_t identity_hash_value_for(Handle obj);
126 static intptr_t FastHashCode(Thread* self, oop obj);
127
128 // java.lang.Thread support
129 static bool current_thread_holds_lock(JavaThread* thread, Handle h_obj);
130 static LockOwnership query_lock_ownership(JavaThread* self, Handle h_obj);
131
132 static JavaThread* get_lock_owner(ThreadsList * t_list, Handle h_obj);
133
134 // JNI detach support
135 static void release_monitors_owned_by_thread(TRAPS);
136 static void monitors_iterate(MonitorClosure* m);
137
138 // GC: we current use aggressive monitor deflation policy
139 // Basically we deflate all monitors that are not busy.
140 // An adaptive profile-based deflation policy could be used if needed
141 static void deflate_idle_monitors(DeflateMonitorCounters* counters);
142 static void deflate_thread_local_monitors(Thread* thread, DeflateMonitorCounters* counters);
143 static void prepare_deflate_idle_monitors(DeflateMonitorCounters* counters);
144 static void finish_deflate_idle_monitors(DeflateMonitorCounters* counters);
145
146 // For a given monitor list: global or per-thread, deflate idle monitors
147 static int deflate_monitor_list(ObjectMonitor** list_p,
148 ObjectMonitor** free_head_p,
149 ObjectMonitor** free_tail_p);
150 static bool deflate_monitor(ObjectMonitor* mid, oop obj,
151 ObjectMonitor** free_head_p,
152 ObjectMonitor** free_tail_p);
153 static bool is_cleanup_needed();
154 static void oops_do(OopClosure* f);
155 // Process oops in thread local used monitors
156 static void thread_local_used_oops_do(Thread* thread, OopClosure* f);
157
158 // debugging
159 static void audit_and_print_stats(bool on_exit);
160 static void chk_free_entry(JavaThread* jt, ObjectMonitor* n,
161 outputStream * out, int *error_cnt_p);
162 static void chk_global_free_list_and_count(outputStream * out,
163 int *error_cnt_p);
164 static void chk_global_in_use_list_and_count(outputStream * out,
165 int *error_cnt_p);
166 static void chk_in_use_entry(JavaThread* jt, ObjectMonitor* n,
167 outputStream * out, int *error_cnt_p);
168 static void chk_per_thread_in_use_list_and_count(JavaThread *jt,
169 outputStream * out,
170 int *error_cnt_p);
171 static void chk_per_thread_free_list_and_count(JavaThread *jt,
172 outputStream * out,
173 int *error_cnt_p);
174 static void log_in_use_monitor_details(outputStream * out, bool on_exit);
175 static int log_monitor_list_counts(outputStream * out);
176 static int verify_objmon_isinpool(ObjectMonitor *addr) PRODUCT_RETURN0;
177
178 private:
179 friend class SynchronizerTest;
180
181 enum { _BLOCKSIZE = 128 };
182 // global list of blocks of monitors
183 static PaddedObjectMonitor* volatile g_block_list;
184 // global monitor free list
185 static ObjectMonitor* volatile g_free_list;
186 // global monitor in-use list, for moribund threads,
187 // monitors they inflated need to be scanned for deflation
188 static ObjectMonitor* volatile g_om_in_use_list;
189 // count of entries in g_om_in_use_list
190 static int g_om_in_use_count;
191
192 // Process oops in all global used monitors (i.e. moribund thread's monitors)
193 static void global_used_oops_do(OopClosure* f);
194 // Process oops in monitors on the given list
195 static void list_oops_do(ObjectMonitor* list, OopClosure* f);
196
197 // Support for SynchronizerTest access to GVars fields:
198 static u_char* get_gvars_addr();
199 static u_char* get_gvars_hc_sequence_addr();
200 static size_t get_gvars_size();
201 static u_char* get_gvars_stw_random_addr();
202 };
203
204 // ObjectLocker enforces balanced locking and can never throw an
205 // IllegalMonitorStateException. However, a pending exception may
206 // have to pass through, and we must also be able to deal with
207 // asynchronous exceptions. The caller is responsible for checking
208 // the thread's pending exception if needed.
209 class ObjectLocker : public StackObj {
210 private:
|
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 #ifndef SHARE_RUNTIME_SYNCHRONIZER_HPP
26 #define SHARE_RUNTIME_SYNCHRONIZER_HPP
27
28 #include "memory/padded.hpp"
29 #include "oops/markWord.hpp"
30 #include "runtime/basicLock.hpp"
31 #include "runtime/handles.hpp"
32 #include "runtime/perfData.hpp"
33
34 class ObjectMonitor;
35 class ObjectMonitorHandle;
36 class ThreadsList;
37
38 typedef PaddedEnd<ObjectMonitor, DEFAULT_CACHE_LINE_SIZE> PaddedObjectMonitor;
39
40 struct DeflateMonitorCounters {
41 int n_in_use; // currently associated with objects
42 int n_in_circulation; // extant
43 int n_scavenged; // reclaimed (global and per-thread)
44 int per_thread_scavenged; // per-thread scavenge total
45 double per_thread_times; // per-thread scavenge times
46 };
47
48 class ObjectSynchronizer : AllStatic {
49 friend class VMStructs;
50 public:
51 typedef enum {
52 owner_self,
53 owner_none,
54 owner_other
55 } LockOwnership;
93 // Handle all interpreter, compiler and jni cases
94 static int wait(Handle obj, jlong millis, TRAPS);
95 static void notify(Handle obj, TRAPS);
96 static void notifyall(Handle obj, TRAPS);
97
98 static bool quick_notify(oopDesc* obj, Thread* self, bool All);
99 static bool quick_enter(oop obj, Thread* self, BasicLock* Lock);
100
101 // Special internal-use-only method for use by JVM infrastructure
102 // that needs to wait() on a java-level object but that can't risk
103 // throwing unexpected InterruptedExecutionExceptions.
104 static void wait_uninterruptibly(Handle obj, jlong Millis, Thread* THREAD);
105
106 // used by classloading to free classloader object lock,
107 // wait on an internal lock, and reclaim original lock
108 // with original recursion count
109 static intptr_t complete_exit(Handle obj, TRAPS);
110 static void reenter (Handle obj, intptr_t recursion, TRAPS);
111
112 // thread-specific and global ObjectMonitor free list accessors
113 static ObjectMonitor* om_alloc(Thread* self, const InflateCause cause);
114 static void om_release(Thread* self, ObjectMonitor* m,
115 bool FromPerThreadAlloc);
116 static void om_flush(Thread* self);
117
118 // Inflate light weight monitor to heavy weight monitor
119 static void inflate(ObjectMonitorHandle* omh_p, Thread* self, oop obj,
120 const InflateCause cause);
121 // This version is only for internal use
122 static void inflate_helper(ObjectMonitorHandle* omh_p, oop obj);
123 static const char* inflate_cause_name(const InflateCause cause);
124
125 // Returns the identity hash value for an oop
126 // NOTE: It may cause monitor inflation
127 static intptr_t identity_hash_value_for(Handle obj);
128 static intptr_t FastHashCode(Thread* self, oop obj);
129
130 // java.lang.Thread support
131 static bool current_thread_holds_lock(JavaThread* thread, Handle h_obj);
132 static LockOwnership query_lock_ownership(JavaThread* self, Handle h_obj);
133
134 static JavaThread* get_lock_owner(ThreadsList * t_list, Handle h_obj);
135
136 // JNI detach support
137 static void release_monitors_owned_by_thread(TRAPS);
138 static void monitors_iterate(MonitorClosure* m);
139
140 // GC: we current use aggressive monitor deflation policy
141 // Basically we deflate all monitors that are not busy.
142 // An adaptive profile-based deflation policy could be used if needed
143 static void deflate_idle_monitors(DeflateMonitorCounters* counters);
144 static void deflate_global_idle_monitors_using_JT();
145 static void deflate_per_thread_idle_monitors_using_JT();
146 static void deflate_common_idle_monitors_using_JT(bool is_global, JavaThread* self);
147 static void deflate_thread_local_monitors(Thread* thread, DeflateMonitorCounters* counters);
148 static void prepare_deflate_idle_monitors(DeflateMonitorCounters* counters);
149 static void finish_deflate_idle_monitors(DeflateMonitorCounters* counters);
150
151 // For a given monitor list: global or per-thread, deflate idle monitors
152 static int deflate_monitor_list(ObjectMonitor** list_p,
153 ObjectMonitor** free_head_p,
154 ObjectMonitor** free_tail_p);
155 // For a given in-use monitor list: global or per-thread, deflate idle
156 // monitors using a JavaThread.
157 static int deflate_monitor_list_using_JT(ObjectMonitor** list_p,
158 ObjectMonitor** free_head_p,
159 ObjectMonitor** free_tail_p,
160 ObjectMonitor** saved_mid_in_use_p);
161 static bool deflate_monitor(ObjectMonitor* mid, oop obj,
162 ObjectMonitor** free_head_p,
163 ObjectMonitor** free_tail_p);
164 static bool deflate_monitor_using_JT(ObjectMonitor* mid,
165 ObjectMonitor** free_head_p,
166 ObjectMonitor** free_tail_p);
167 static bool is_async_deflation_needed();
168 static bool is_safepoint_deflation_needed();
169 static bool is_async_deflation_requested() { return _is_async_deflation_requested; }
170 static bool is_special_deflation_requested() { return _is_special_deflation_requested; }
171 static void set_is_async_deflation_requested(bool new_value) { _is_async_deflation_requested = new_value; }
172 static void set_is_special_deflation_requested(bool new_value) { _is_special_deflation_requested = new_value; }
173 static jlong time_since_last_async_deflation_ms();
174 static void oops_do(OopClosure* f);
175 // Process oops in thread local used monitors
176 static void thread_local_used_oops_do(Thread* thread, OopClosure* f);
177
178 // debugging
179 static void audit_and_print_stats(bool on_exit);
180 static void chk_free_entry(JavaThread* jt, ObjectMonitor* n,
181 outputStream * out, int *error_cnt_p);
182 static void chk_global_free_list_and_count(outputStream * out,
183 int *error_cnt_p);
184 static void chk_global_in_use_list_and_count(outputStream * out,
185 int *error_cnt_p);
186 static void chk_in_use_entry(JavaThread* jt, ObjectMonitor* n,
187 outputStream * out, int *error_cnt_p);
188 static void chk_per_thread_in_use_list_and_count(JavaThread *jt,
189 outputStream * out,
190 int *error_cnt_p);
191 static void chk_per_thread_free_list_and_count(JavaThread *jt,
192 outputStream * out,
193 int *error_cnt_p);
194 static void log_in_use_monitor_details(outputStream * out, bool on_exit);
195 static int log_monitor_list_counts(outputStream * out);
196 static int verify_objmon_isinpool(ObjectMonitor *addr) PRODUCT_RETURN0;
197
198 static void do_safepoint_work(DeflateMonitorCounters* _counters);
199
200 private:
201 friend class SynchronizerTest;
202
203 enum { _BLOCKSIZE = 128 };
204 // global list of blocks of monitors
205 static PaddedObjectMonitor* volatile g_block_list;
206 // global monitor free list
207 static ObjectMonitor* volatile g_free_list;
208 // global monitor in-use list, for moribund threads,
209 // monitors they inflated need to be scanned for deflation
210 static ObjectMonitor* volatile g_om_in_use_list;
211 // count of entries in g_om_in_use_list
212 static int g_om_in_use_count;
213 static volatile bool _is_async_deflation_requested;
214 static volatile bool _is_special_deflation_requested;
215 static jlong _last_async_deflation_time_ns;
216
217 // Process oops in all global used monitors (i.e. moribund thread's monitors)
218 static void global_used_oops_do(OopClosure* f);
219 // Process oops in monitors on the given list
220 static void list_oops_do(ObjectMonitor* list, OopClosure* f);
221
222 // Support for SynchronizerTest access to GVars fields:
223 static u_char* get_gvars_addr();
224 static u_char* get_gvars_hc_sequence_addr();
225 static size_t get_gvars_size();
226 static u_char* get_gvars_stw_random_addr();
227 };
228
229 // ObjectLocker enforces balanced locking and can never throw an
230 // IllegalMonitorStateException. However, a pending exception may
231 // have to pass through, and we must also be able to deal with
232 // asynchronous exceptions. The caller is responsible for checking
233 // the thread's pending exception if needed.
234 class ObjectLocker : public StackObj {
235 private:
|