1 /*
  2  * Copyright (c) 2017, 2021, Red Hat, Inc. 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 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHUTILS_HPP
 26 #define SHARE_GC_SHENANDOAH_SHENANDOAHUTILS_HPP
 27 
 28 #include "gc/shared/gcCause.hpp"
 29 #include "gc/shared/gcTraceTime.inline.hpp"
 30 #include "gc/shared/gcVMOperations.hpp"
 31 #include "gc/shared/isGCActiveMark.hpp"
 32 #include "gc/shared/suspendibleThreadSet.hpp"
 33 #include "gc/shared/workerThread.hpp"
 34 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
 35 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
 36 #include "jfr/jfrEvents.hpp"
 37 #include "memory/allocation.hpp"
 38 #include "runtime/safepoint.hpp"
 39 #include "runtime/vmThread.hpp"
 40 #include "runtime/vmOperations.hpp"
 41 #include "services/memoryService.hpp"
 42 
 43 class GCTimer;
 44 
 45 class ShenandoahGCSession : public StackObj {
 46 private:
 47   ShenandoahHeap* const _heap;
 48   GCTimer*  const _timer;
 49   GCTracer* const _tracer;
 50 
 51   TraceMemoryManagerStats _trace_cycle;
 52 public:
 53   ShenandoahGCSession(GCCause::Cause cause);
 54   ~ShenandoahGCSession();
 55 };
 56 
 57 /*
 58  * ShenandoahGCPhaseTiming tracks Shenandoah specific timing information
 59  * of a GC phase
 60  */
 61 class ShenandoahTimingsTracker : public StackObj {
 62 private:
 63   static ShenandoahPhaseTimings::Phase  _current_phase;
 64 
 65   ShenandoahPhaseTimings* const         _timings;
 66   const ShenandoahPhaseTimings::Phase   _phase;
 67   ShenandoahPhaseTimings::Phase         _parent_phase;
 68   double _start;
 69 
 70 public:
 71   ShenandoahTimingsTracker(ShenandoahPhaseTimings::Phase phase);
 72   ~ShenandoahTimingsTracker();
 73 
 74   static ShenandoahPhaseTimings::Phase current_phase() { return _current_phase; }
 75 
 76   static bool is_current_phase_valid();
 77 };
 78 
 79 /*
 80  * ShenandoahPausePhase tracks a STW pause and emits Shenandoah timing and
 81  * a corresponding JFR event
 82  */
 83 class ShenandoahPausePhase : public ShenandoahTimingsTracker {
 84 private:
 85   GCTraceTimeWrapper<LogLevel::Info, LOG_TAGS(gc)> _tracer;
 86   ConcurrentGCTimer* const _timer;
 87 
 88 public:
 89   ShenandoahPausePhase(const char* title, ShenandoahPhaseTimings::Phase phase, bool log_heap_usage = false);
 90   ~ShenandoahPausePhase();
 91 };
 92 
 93 /*
 94  * ShenandoahConcurrentPhase tracks a concurrent GC phase and emits Shenandoah timing and
 95  * a corresponding JFR event
 96  */
 97 class ShenandoahConcurrentPhase : public ShenandoahTimingsTracker {
 98 private:
 99   GCTraceTimeWrapper<LogLevel::Info, LOG_TAGS(gc)> _tracer;
100   ConcurrentGCTimer* const _timer;
101 
102 public:
103   ShenandoahConcurrentPhase(const char* title, ShenandoahPhaseTimings::Phase phase, bool log_heap_usage = false);
104   ~ShenandoahConcurrentPhase();
105 };
106 
107 /*
108  * ShenandoahGCPhase tracks Shenandoah specific timing information
109  * and emits a corresponding JFR event of a GC phase
110  */
111 class ShenandoahGCPhase : public ShenandoahTimingsTracker {
112 private:
113   ConcurrentGCTimer* const _timer;
114 
115 public:
116   ShenandoahGCPhase(ShenandoahPhaseTimings::Phase phase);
117   ~ShenandoahGCPhase();
118 };
119 
120 class ShenandoahGCWorkerPhase : public StackObj {
121 private:
122   ShenandoahPhaseTimings* const       _timings;
123   const ShenandoahPhaseTimings::Phase _phase;
124 public:
125   ShenandoahGCWorkerPhase(ShenandoahPhaseTimings::Phase phase);
126   ~ShenandoahGCWorkerPhase();
127 };
128 
129 // Aggregates all the things that should happen before/after the pause.
130 class ShenandoahGCPauseMark : public StackObj {
131 private:
132   ShenandoahHeap* const _heap;
133   const GCIdMark                _gc_id_mark;
134   const SvcGCMarker             _svc_gc_mark;
135   const IsGCActiveMark          _is_gc_active_mark;
136   TraceMemoryManagerStats       _trace_pause;
137 
138 public:
139   ShenandoahGCPauseMark(uint gc_id, SvcGCMarker::reason_type type);
140 };
141 
142 class ShenandoahSafepoint : public AllStatic {
143 public:
144   // Check if Shenandoah GC safepoint is in progress. This is nominally
145   // equivalent to calling SafepointSynchronize::is_at_safepoint(), but
146   // it also checks the Shenandoah specifics, when it can.
147   static inline bool is_at_shenandoah_safepoint() {
148     if (!SafepointSynchronize::is_at_safepoint()) return false;
149 
150     Thread* const thr = Thread::current();
151     // Shenandoah GC specific safepoints are scheduled by control thread.
152     // So if we are enter here from control thread, then we are definitely not
153     // at Shenandoah safepoint, but at something else.
154     if (thr == ShenandoahHeap::heap()->control_thread()) return false;
155 
156     // This is not VM thread, cannot see what VM thread is doing,
157     // so pretend this is a proper Shenandoah safepoint
158     if (!thr->is_VM_thread()) return true;
159 
160     // Otherwise check we are at proper operation type
161     VM_Operation* vm_op = VMThread::vm_operation();
162     if (vm_op == NULL) return false;
163 
164     VM_Operation::VMOp_Type type = vm_op->type();
165     return type == VM_Operation::VMOp_ShenandoahInitMark ||
166            type == VM_Operation::VMOp_ShenandoahFinalMarkStartEvac ||
167            type == VM_Operation::VMOp_ShenandoahInitUpdateRefs ||
168            type == VM_Operation::VMOp_ShenandoahFinalUpdateRefs ||
169            type == VM_Operation::VMOp_ShenandoahFinalRoots ||
170            type == VM_Operation::VMOp_ShenandoahFullGC ||
171            type == VM_Operation::VMOp_ShenandoahDegeneratedGC;
172   }
173 };
174 
175 class ShenandoahWorkerSession : public StackObj {
176 protected:
177   ShenandoahWorkerSession(uint worker_id);
178 public:
179   static inline uint worker_id() {
180     return WorkerThread::worker_id();
181   }
182 };
183 
184 class ShenandoahConcurrentWorkerSession : public ShenandoahWorkerSession {
185 private:
186   EventGCPhaseConcurrent _event;
187 
188 public:
189   ShenandoahConcurrentWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
190   ~ShenandoahConcurrentWorkerSession();
191 };
192 
193 class ShenandoahParallelWorkerSession : public ShenandoahWorkerSession {
194 private:
195   EventGCPhaseParallel _event;
196 
197 public:
198   ShenandoahParallelWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
199   ~ShenandoahParallelWorkerSession();
200 };
201 
202 class ShenandoahSuspendibleThreadSetJoiner {
203 private:
204   SuspendibleThreadSetJoiner _joiner;
205 public:
206   ShenandoahSuspendibleThreadSetJoiner(bool active = true) : _joiner(active) {
207     assert(!ShenandoahThreadLocalData::is_evac_allowed(Thread::current()), "STS should be joined before evac scope");
208   }
209   ~ShenandoahSuspendibleThreadSetJoiner() {
210     assert(!ShenandoahThreadLocalData::is_evac_allowed(Thread::current()), "STS should be left after evac scope");
211   }
212 };
213 
214 class ShenandoahSuspendibleThreadSetLeaver {
215 private:
216   SuspendibleThreadSetLeaver _leaver;
217 public:
218   ShenandoahSuspendibleThreadSetLeaver(bool active = true) : _leaver(active) {
219     assert(!ShenandoahThreadLocalData::is_evac_allowed(Thread::current()), "STS should be left after evac scope");
220   }
221   ~ShenandoahSuspendibleThreadSetLeaver() {
222     assert(!ShenandoahThreadLocalData::is_evac_allowed(Thread::current()), "STS should be joined before evac scope");
223   }
224 };
225 
226 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHUTILS_HPP