1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ART_RUNTIME_TRACE_H_
18#define ART_RUNTIME_TRACE_H_
19
20#include <memory>
21#include <ostream>
22#include <set>
23#include <string>
24#include <vector>
25
26#include "atomic.h"
27#include "base/macros.h"
28#include "globals.h"
29#include "instrumentation.h"
30#include "os.h"
31#include "safe_map.h"
32
33namespace art {
34
35namespace mirror {
36  class ArtField;
37  class ArtMethod;
38}  // namespace mirror
39
40class Thread;
41
42enum TracingMode {
43  kTracingInactive,
44  kMethodTracingActive,
45  kSampleProfilingActive,
46};
47
48class Trace FINAL : public instrumentation::InstrumentationListener {
49 public:
50  enum TraceFlag {
51    kTraceCountAllocs = 1,
52  };
53
54  static void SetDefaultClockSource(TraceClockSource clock_source);
55
56  static void Start(const char* trace_filename, int trace_fd, int buffer_size, int flags,
57                    bool direct_to_ddms, bool sampling_enabled, int interval_us)
58      LOCKS_EXCLUDED(Locks::mutator_lock_,
59                     Locks::thread_list_lock_,
60                     Locks::thread_suspend_count_lock_,
61                     Locks::trace_lock_);
62  static void Stop()
63      LOCKS_EXCLUDED(Locks::mutator_lock_,
64                     Locks::thread_list_lock_,
65                     Locks::trace_lock_);
66  static void Shutdown() LOCKS_EXCLUDED(Locks::trace_lock_);
67  static TracingMode GetMethodTracingMode() LOCKS_EXCLUDED(Locks::trace_lock_);
68
69  bool UseWallClock();
70  bool UseThreadCpuClock();
71  void MeasureClockOverhead();
72  uint32_t GetClockOverheadNanoSeconds();
73
74  void CompareAndUpdateStackTrace(Thread* thread, std::vector<mirror::ArtMethod*>* stack_trace)
75      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
76
77  // InstrumentationListener implementation.
78  void MethodEntered(Thread* thread, mirror::Object* this_object,
79                     mirror::ArtMethod* method, uint32_t dex_pc)
80      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
81  void MethodExited(Thread* thread, mirror::Object* this_object,
82                    mirror::ArtMethod* method, uint32_t dex_pc,
83                    const JValue& return_value)
84      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
85  void MethodUnwind(Thread* thread, mirror::Object* this_object,
86                    mirror::ArtMethod* method, uint32_t dex_pc)
87      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
88  void DexPcMoved(Thread* thread, mirror::Object* this_object,
89                  mirror::ArtMethod* method, uint32_t new_dex_pc)
90      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
91  void FieldRead(Thread* thread, mirror::Object* this_object,
92                 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field)
93      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
94  void FieldWritten(Thread* thread, mirror::Object* this_object,
95                    mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field,
96                    const JValue& field_value)
97      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
98  void ExceptionCaught(Thread* thread, const ThrowLocation& throw_location,
99                       mirror::ArtMethod* catch_method, uint32_t catch_dex_pc,
100                       mirror::Throwable* exception_object)
101      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
102
103  // Reuse an old stack trace if it exists, otherwise allocate a new one.
104  static std::vector<mirror::ArtMethod*>* AllocStackTrace();
105  // Clear and store an old stack trace for later use.
106  static void FreeStackTrace(std::vector<mirror::ArtMethod*>* stack_trace);
107
108 private:
109  explicit Trace(File* trace_file, int buffer_size, int flags, bool sampling_enabled);
110
111  // The sampling interval in microseconds is passed as an argument.
112  static void* RunSamplingThread(void* arg) LOCKS_EXCLUDED(Locks::trace_lock_);
113
114  void FinishTracing() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
115
116  void ReadClocks(Thread* thread, uint32_t* thread_clock_diff, uint32_t* wall_clock_diff);
117
118  void LogMethodTraceEvent(Thread* thread, mirror::ArtMethod* method,
119                           instrumentation::Instrumentation::InstrumentationEvent event,
120                           uint32_t thread_clock_diff, uint32_t wall_clock_diff);
121
122  // Methods to output traced methods and threads.
123  void GetVisitedMethods(size_t end_offset, std::set<mirror::ArtMethod*>* visited_methods);
124  void DumpMethodList(std::ostream& os, const std::set<mirror::ArtMethod*>& visited_methods)
125      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
126  void DumpThreadList(std::ostream& os) LOCKS_EXCLUDED(Locks::thread_list_lock_);
127
128  // Singleton instance of the Trace or NULL when no method tracing is active.
129  static Trace* volatile the_trace_ GUARDED_BY(Locks::trace_lock_);
130
131  // The default profiler clock source.
132  static TraceClockSource default_clock_source_;
133
134  // Sampling thread, non-zero when sampling.
135  static pthread_t sampling_pthread_;
136
137  // Used to remember an unused stack trace to avoid re-allocation during sampling.
138  static std::unique_ptr<std::vector<mirror::ArtMethod*>> temp_stack_trace_;
139
140  // File to write trace data out to, NULL if direct to ddms.
141  std::unique_ptr<File> trace_file_;
142
143  // Buffer to store trace data.
144  std::unique_ptr<uint8_t> buf_;
145
146  // Flags enabling extra tracing of things such as alloc counts.
147  const int flags_;
148
149  // True if traceview should sample instead of instrumenting method entry/exit.
150  const bool sampling_enabled_;
151
152  const TraceClockSource clock_source_;
153
154  // Size of buf_.
155  const int buffer_size_;
156
157  // Time trace was created.
158  const uint64_t start_time_;
159
160  // Clock overhead.
161  const uint32_t clock_overhead_ns_;
162
163  // Offset into buf_.
164  AtomicInteger cur_offset_;
165
166  // Did we overflow the buffer recording traces?
167  bool overflow_;
168
169  DISALLOW_COPY_AND_ASSIGN(Trace);
170};
171
172}  // namespace art
173
174#endif  // ART_RUNTIME_TRACE_H_
175