151 class BiasedLocking : AllStatic {
152 friend class VM_BulkRevokeBias;
153 friend class RevokeOneBias;
154
155 private:
156 static BiasedLockingCounters _counters;
157
158 public:
159 static int* total_entry_count_addr();
160 static int* biased_lock_entry_count_addr();
161 static int* anonymously_biased_lock_entry_count_addr();
162 static int* rebiased_lock_entry_count_addr();
163 static int* revoked_lock_entry_count_addr();
164 static int* handshakes_count_addr();
165 static int* fast_path_entry_count_addr();
166 static int* slow_path_entry_count_addr();
167
168 enum Condition {
169 NOT_BIASED = 1,
170 BIAS_REVOKED = 2,
171 BIAS_REVOKED_AND_REBIASED = 3,
172 NOT_REVOKED = 4
173 };
174
175 private:
176 static Condition single_revoke_at_safepoint(oop obj, bool allow_rebias, bool is_bulk, JavaThread* requester, JavaThread** biaser);
177 static Condition bulk_revoke_or_rebias_at_safepoint(oop o, bool bulk_rebias, bool attempt_rebias, JavaThread* requester);
178 static Condition single_revoke_with_handshake(Handle obj, JavaThread *requester, JavaThread *biaser);
179 static void walk_stack_and_revoke(oop obj, JavaThread* biased_locker);
180
181 public:
182 // This initialization routine should only be called once and
183 // schedules a PeriodicTask to turn on biased locking a few seconds
184 // into the VM run to avoid startup time regressions
185 static void init();
186
187 // This provides a global switch for leaving biased locking disabled
188 // for the first part of a run and enabling it later
189 static bool enabled();
190
191 // This should be called by JavaThreads to revoke the bias of an object
192 static Condition revoke_and_rebias(Handle obj, bool attempt_rebias, TRAPS);
193
194 // These do not allow rebiasing; they are used by deoptimization to
195 // ensure that monitors on the stack can be migrated
196 static void revoke(GrowableArray<Handle>* objs, JavaThread *biaser);
197 static void revoke_at_safepoint(Handle obj);
198 static void revoke_at_safepoint(GrowableArray<Handle>* objs);
199
200 static void print_counters() { _counters.print(); }
201 static BiasedLockingCounters* counters() { return &_counters; }
202
203 // These routines are GC-related and should not be called by end
204 // users. GCs which do not do preservation of mark words do not need
205 // to call these routines.
206 static void preserve_marks();
207 static void restore_marks();
208 };
209
210 #endif // SHARE_RUNTIME_BIASEDLOCKING_HPP
|
151 class BiasedLocking : AllStatic {
152 friend class VM_BulkRevokeBias;
153 friend class RevokeOneBias;
154
155 private:
156 static BiasedLockingCounters _counters;
157
158 public:
159 static int* total_entry_count_addr();
160 static int* biased_lock_entry_count_addr();
161 static int* anonymously_biased_lock_entry_count_addr();
162 static int* rebiased_lock_entry_count_addr();
163 static int* revoked_lock_entry_count_addr();
164 static int* handshakes_count_addr();
165 static int* fast_path_entry_count_addr();
166 static int* slow_path_entry_count_addr();
167
168 enum Condition {
169 NOT_BIASED = 1,
170 BIAS_REVOKED = 2,
171 NOT_REVOKED = 3
172 };
173
174 private:
175 static void single_revoke_at_safepoint(oop obj, bool is_bulk, JavaThread* requester, JavaThread** biaser);
176 static void bulk_revoke_at_safepoint(oop o, bool bulk_rebias, JavaThread* requester);
177 static Condition single_revoke_with_handshake(Handle obj, JavaThread *requester, JavaThread *biaser);
178 static void walk_stack_and_revoke(oop obj, JavaThread* biased_locker);
179
180 public:
181 // This initialization routine should only be called once and
182 // schedules a PeriodicTask to turn on biased locking a few seconds
183 // into the VM run to avoid startup time regressions
184 static void init();
185
186 // This provides a global switch for leaving biased locking disabled
187 // for the first part of a run and enabling it later
188 static bool enabled();
189
190 // This should be called by JavaThreads to revoke the bias of an object
191 static void revoke(Handle obj, TRAPS);
192
193 static void revoke_at_safepoint(Handle obj);
194
195 // These are used by deoptimization to ensure that monitors on the stack
196 // can be migrated
197 static void revoke(GrowableArray<Handle>* objs, JavaThread *biaser);
198 static void revoke_at_safepoint(GrowableArray<Handle>* objs);
199
200 static void print_counters() { _counters.print(); }
201 static BiasedLockingCounters* counters() { return &_counters; }
202
203 // These routines are GC-related and should not be called by end
204 // users. GCs which do not do preservation of mark words do not need
205 // to call these routines.
206 static void preserve_marks();
207 static void restore_marks();
208 };
209
210 #endif // SHARE_RUNTIME_BIASEDLOCKING_HPP
|