profile-generator.h revision 7f4d5bd8c03935e2c0cd412e561b8fc5a6a880ae 
1// Copyright 2010 the V8 project authors. All rights reserved.
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3// modification, are permitted provided that the following conditions are
4// met:
5//
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7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
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11//       with the distribution.
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15//
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22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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27
28#ifndef V8_PROFILE_GENERATOR_H_
29#define V8_PROFILE_GENERATOR_H_
30
31#ifdef ENABLE_LOGGING_AND_PROFILING
32
33#include "hashmap.h"
34#include "../include/v8-profiler.h"
35
36namespace v8 {
37namespace internal {
38
39class TokenEnumerator {
40 public:
41  TokenEnumerator();
42  ~TokenEnumerator();
43  int GetTokenId(Object* token);
44
45  static const int kNoSecurityToken = -1;
46  static const int kInheritsSecurityToken = -2;
47
48 private:
49  static void TokenRemovedCallback(v8::Persistent<v8::Value> handle,
50                                   void* parameter);
51  void TokenRemoved(Object** token_location);
52
53  List<Object**> token_locations_;
54  List<bool> token_removed_;
55
56  friend class TokenEnumeratorTester;
57
58  DISALLOW_COPY_AND_ASSIGN(TokenEnumerator);
59};
60
61
62// Provides a storage of strings allocated in C++ heap, to hold them
63// forever, even if they disappear from JS heap or external storage.
64class StringsStorage {
65 public:
66  StringsStorage();
67  ~StringsStorage();
68
69  const char* GetName(String* name);
70
71 private:
72  INLINE(static bool StringsMatch(void* key1, void* key2)) {
73    return strcmp(reinterpret_cast<char*>(key1),
74                  reinterpret_cast<char*>(key2)) == 0;
75  }
76
77  // String::Hash -> const char*
78  HashMap names_;
79
80  DISALLOW_COPY_AND_ASSIGN(StringsStorage);
81};
82
83
84class CodeEntry {
85 public:
86  explicit INLINE(CodeEntry(int security_token_id));
87  // CodeEntry doesn't own name strings, just references them.
88  INLINE(CodeEntry(Logger::LogEventsAndTags tag,
89                   const char* name_prefix,
90                   const char* name,
91                   const char* resource_name,
92                   int line_number,
93                   int security_token_id));
94
95  INLINE(bool is_js_function() const) { return is_js_function_tag(tag_); }
96  INLINE(const char* name_prefix() const) { return name_prefix_; }
97  INLINE(bool has_name_prefix() const) { return name_prefix_[0] != '\0'; }
98  INLINE(const char* name() const) { return name_; }
99  INLINE(const char* resource_name() const) { return resource_name_; }
100  INLINE(int line_number() const) { return line_number_; }
101  INLINE(unsigned call_uid() const) { return call_uid_; }
102  INLINE(int security_token_id() const) { return security_token_id_; }
103
104  INLINE(static bool is_js_function_tag(Logger::LogEventsAndTags tag));
105
106  void CopyData(const CodeEntry& source);
107
108  static const char* kEmptyNamePrefix;
109
110 private:
111  unsigned call_uid_;
112  Logger::LogEventsAndTags tag_;
113  const char* name_prefix_;
114  const char* name_;
115  const char* resource_name_;
116  int line_number_;
117  int security_token_id_;
118
119  static unsigned next_call_uid_;
120
121  DISALLOW_COPY_AND_ASSIGN(CodeEntry);
122};
123
124
125class ProfileTree;
126
127class ProfileNode {
128 public:
129  INLINE(ProfileNode(ProfileTree* tree, CodeEntry* entry));
130
131  ProfileNode* FindChild(CodeEntry* entry);
132  ProfileNode* FindOrAddChild(CodeEntry* entry);
133  INLINE(void IncrementSelfTicks()) { ++self_ticks_; }
134  INLINE(void IncreaseSelfTicks(unsigned amount)) { self_ticks_ += amount; }
135  INLINE(void IncreaseTotalTicks(unsigned amount)) { total_ticks_ += amount; }
136
137  INLINE(CodeEntry* entry() const) { return entry_; }
138  INLINE(unsigned self_ticks() const) { return self_ticks_; }
139  INLINE(unsigned total_ticks() const) { return total_ticks_; }
140  INLINE(const List<ProfileNode*>* children() const) { return &children_list_; }
141  double GetSelfMillis() const;
142  double GetTotalMillis() const;
143
144  void Print(int indent);
145
146 private:
147  INLINE(static bool CodeEntriesMatch(void* entry1, void* entry2)) {
148    return entry1 == entry2;
149  }
150
151  INLINE(static uint32_t CodeEntryHash(CodeEntry* entry)) {
152    return static_cast<int32_t>(reinterpret_cast<intptr_t>(entry));
153  }
154
155  ProfileTree* tree_;
156  CodeEntry* entry_;
157  unsigned total_ticks_;
158  unsigned self_ticks_;
159  // CodeEntry* -> ProfileNode*
160  HashMap children_;
161  List<ProfileNode*> children_list_;
162
163  DISALLOW_COPY_AND_ASSIGN(ProfileNode);
164};
165
166
167class ProfileTree {
168 public:
169  ProfileTree();
170  ~ProfileTree();
171
172  void AddPathFromEnd(const Vector<CodeEntry*>& path);
173  void AddPathFromStart(const Vector<CodeEntry*>& path);
174  void CalculateTotalTicks();
175  void FilteredClone(ProfileTree* src, int security_token_id);
176
177  double TicksToMillis(unsigned ticks) const {
178    return ticks * ms_to_ticks_scale_;
179  }
180  ProfileNode* root() const { return root_; }
181  void SetTickRatePerMs(double ticks_per_ms);
182
183  void ShortPrint();
184  void Print() {
185    root_->Print(0);
186  }
187
188 private:
189  template <typename Callback>
190  void TraverseDepthFirst(Callback* callback);
191
192  CodeEntry root_entry_;
193  ProfileNode* root_;
194  double ms_to_ticks_scale_;
195
196  DISALLOW_COPY_AND_ASSIGN(ProfileTree);
197};
198
199
200class CpuProfile {
201 public:
202  CpuProfile(const char* title, unsigned uid)
203      : title_(title), uid_(uid) { }
204
205  // Add pc -> ... -> main() call path to the profile.
206  void AddPath(const Vector<CodeEntry*>& path);
207  void CalculateTotalTicks();
208  void SetActualSamplingRate(double actual_sampling_rate);
209  CpuProfile* FilteredClone(int security_token_id);
210
211  INLINE(const char* title() const) { return title_; }
212  INLINE(unsigned uid() const) { return uid_; }
213  INLINE(const ProfileTree* top_down() const) { return &top_down_; }
214  INLINE(const ProfileTree* bottom_up() const) { return &bottom_up_; }
215
216  void UpdateTicksScale();
217
218  void ShortPrint();
219  void Print();
220
221 private:
222  const char* title_;
223  unsigned uid_;
224  ProfileTree top_down_;
225  ProfileTree bottom_up_;
226
227  DISALLOW_COPY_AND_ASSIGN(CpuProfile);
228};
229
230
231class CodeMap {
232 public:
233  CodeMap() { }
234  INLINE(void AddCode(Address addr, CodeEntry* entry, unsigned size));
235  INLINE(void MoveCode(Address from, Address to));
236  INLINE(void DeleteCode(Address addr));
237  void AddAlias(Address start, CodeEntry* entry, Address code_start);
238  CodeEntry* FindEntry(Address addr);
239
240  void Print();
241
242 private:
243  struct CodeEntryInfo {
244    CodeEntryInfo(CodeEntry* an_entry, unsigned a_size)
245        : entry(an_entry), size(a_size) { }
246    CodeEntry* entry;
247    unsigned size;
248  };
249
250  struct CodeTreeConfig {
251    typedef Address Key;
252    typedef CodeEntryInfo Value;
253    static const Key kNoKey;
254    static const Value kNoValue;
255    static int Compare(const Key& a, const Key& b) {
256      return a < b ? -1 : (a > b ? 1 : 0);
257    }
258  };
259  typedef SplayTree<CodeTreeConfig> CodeTree;
260
261  class CodeTreePrinter {
262   public:
263    void Call(const Address& key, const CodeEntryInfo& value);
264  };
265
266  CodeTree tree_;
267
268  DISALLOW_COPY_AND_ASSIGN(CodeMap);
269};
270
271
272class CpuProfilesCollection {
273 public:
274  CpuProfilesCollection();
275  ~CpuProfilesCollection();
276
277  bool StartProfiling(const char* title, unsigned uid);
278  bool StartProfiling(String* title, unsigned uid);
279  CpuProfile* StopProfiling(int security_token_id,
280                            const char* title,
281                            double actual_sampling_rate);
282  CpuProfile* StopProfiling(int security_token_id,
283                            String* title,
284                            double actual_sampling_rate);
285  List<CpuProfile*>* Profiles(int security_token_id);
286  const char* GetName(String* name) {
287    return function_and_resource_names_.GetName(name);
288  }
289  CpuProfile* GetProfile(int security_token_id, unsigned uid);
290  inline bool is_last_profile();
291
292  CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag,
293                          String* name, String* resource_name, int line_number);
294  CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag, const char* name);
295  CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag,
296                          const char* name_prefix, String* name);
297  CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag, int args_count);
298  CodeEntry* NewCodeEntry(int security_token_id);
299
300  // Called from profile generator thread.
301  void AddPathToCurrentProfiles(const Vector<CodeEntry*>& path);
302
303 private:
304  INLINE(const char* GetFunctionName(String* name));
305  INLINE(const char* GetFunctionName(const char* name));
306  const char* GetName(int args_count);
307  List<CpuProfile*>* GetProfilesList(int security_token_id);
308  int TokenToIndex(int security_token_id);
309
310  INLINE(static bool UidsMatch(void* key1, void* key2)) {
311    return key1 == key2;
312  }
313
314  StringsStorage function_and_resource_names_;
315  // args_count -> char*
316  List<char*> args_count_names_;
317  List<CodeEntry*> code_entries_;
318  List<List<CpuProfile*>* > profiles_by_token_;
319  // uid -> index
320  HashMap profiles_uids_;
321
322  // Accessed by VM thread and profile generator thread.
323  List<CpuProfile*> current_profiles_;
324  Semaphore* current_profiles_semaphore_;
325
326  DISALLOW_COPY_AND_ASSIGN(CpuProfilesCollection);
327};
328
329
330class SampleRateCalculator {
331 public:
332  SampleRateCalculator()
333      : result_(Logger::kSamplingIntervalMs * kResultScale),
334        ticks_per_ms_(Logger::kSamplingIntervalMs),
335        measurements_count_(0),
336        wall_time_query_countdown_(1) {
337  }
338
339  double ticks_per_ms() {
340    return result_ / static_cast<double>(kResultScale);
341  }
342  void Tick();
343  void UpdateMeasurements(double current_time);
344
345  // Instead of querying current wall time each tick,
346  // we use this constant to control query intervals.
347  static const unsigned kWallTimeQueryIntervalMs = 100;
348
349 private:
350  // As the result needs to be accessed from a different thread, we
351  // use type that guarantees atomic writes to memory.  There should
352  // be <= 1000 ticks per second, thus storing a value of a 10 ** 5
353  // order should provide enough precision while keeping away from a
354  // potential overflow.
355  static const int kResultScale = 100000;
356
357  AtomicWord result_;
358  // All other fields are accessed only from the sampler thread.
359  double ticks_per_ms_;
360  unsigned measurements_count_;
361  unsigned wall_time_query_countdown_;
362  double last_wall_time_;
363
364  DISALLOW_COPY_AND_ASSIGN(SampleRateCalculator);
365};
366
367
368class ProfileGenerator {
369 public:
370  explicit ProfileGenerator(CpuProfilesCollection* profiles);
371
372  INLINE(CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag,
373                                 String* name,
374                                 String* resource_name,
375                                 int line_number)) {
376    return profiles_->NewCodeEntry(tag, name, resource_name, line_number);
377  }
378
379  INLINE(CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag,
380                                 const char* name)) {
381    return profiles_->NewCodeEntry(tag, name);
382  }
383
384  INLINE(CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag,
385                                 const char* name_prefix,
386                                 String* name)) {
387    return profiles_->NewCodeEntry(tag, name_prefix, name);
388  }
389
390  INLINE(CodeEntry* NewCodeEntry(Logger::LogEventsAndTags tag,
391                                 int args_count)) {
392    return profiles_->NewCodeEntry(tag, args_count);
393  }
394
395  INLINE(CodeEntry* NewCodeEntry(int security_token_id)) {
396    return profiles_->NewCodeEntry(security_token_id);
397  }
398
399  void RecordTickSample(const TickSample& sample);
400
401  INLINE(CodeMap* code_map()) { return &code_map_; }
402
403  INLINE(void Tick()) { sample_rate_calc_.Tick(); }
404  INLINE(double actual_sampling_rate()) {
405    return sample_rate_calc_.ticks_per_ms();
406  }
407
408  static const char* kAnonymousFunctionName;
409  static const char* kProgramEntryName;
410  static const char* kGarbageCollectorEntryName;
411
412 private:
413  INLINE(CodeEntry* EntryForVMState(StateTag tag));
414
415  CpuProfilesCollection* profiles_;
416  CodeMap code_map_;
417  CodeEntry* program_entry_;
418  CodeEntry* gc_entry_;
419  SampleRateCalculator sample_rate_calc_;
420
421  DISALLOW_COPY_AND_ASSIGN(ProfileGenerator);
422};
423
424
425class HeapSnapshot;
426class HeapEntry;
427
428
429class HeapGraphEdge {
430 public:
431  enum Type {
432    CONTEXT_VARIABLE,
433    ELEMENT,
434    PROPERTY
435  };
436
437  HeapGraphEdge(Type type, const char* name, HeapEntry* from, HeapEntry* to);
438  HeapGraphEdge(int index, HeapEntry* from, HeapEntry* to);
439
440  Type type() const { return type_; }
441  int index() const {
442    ASSERT(type_ == ELEMENT);
443    return index_;
444  }
445  const char* name() const {
446    ASSERT(type_ == CONTEXT_VARIABLE || type_ == PROPERTY);
447    return name_;
448  }
449  HeapEntry* from() const { return from_; }
450  HeapEntry* to() const { return to_; }
451
452 private:
453  Type type_;
454  union {
455    int index_;
456    const char* name_;
457  };
458  HeapEntry* from_;
459  HeapEntry* to_;
460
461  DISALLOW_COPY_AND_ASSIGN(HeapGraphEdge);
462};
463
464
465class HeapGraphPath;
466class CachedHeapGraphPath;
467
468class HeapEntry {
469 public:
470  enum Type {
471    INTERNAL,
472    ARRAY,
473    STRING,
474    JS_OBJECT,
475    CODE,
476    CLOSURE
477  };
478
479  explicit HeapEntry(HeapSnapshot* snapshot)
480      : snapshot_(snapshot),
481        visited_(false),
482        type_(INTERNAL),
483        name_(""),
484        next_auto_index_(0),
485        self_size_(0),
486        security_token_id_(TokenEnumerator::kNoSecurityToken),
487        children_(1),
488        retainers_(0),
489        retaining_paths_(0),
490        total_size_(kUnknownSize),
491        non_shared_total_size_(kUnknownSize),
492        painted_(kUnpainted) { }
493  HeapEntry(HeapSnapshot* snapshot,
494            Type type,
495            const char* name,
496            int self_size,
497            int security_token_id)
498      : snapshot_(snapshot),
499        visited_(false),
500        type_(type),
501        name_(name),
502        next_auto_index_(1),
503        self_size_(self_size),
504        security_token_id_(security_token_id),
505        children_(4),
506        retainers_(4),
507        retaining_paths_(4),
508        total_size_(kUnknownSize),
509        non_shared_total_size_(kUnknownSize),
510        painted_(kUnpainted) { }
511  ~HeapEntry();
512
513  bool visited() const { return visited_; }
514  Type type() const { return type_; }
515  const char* name() const { return name_; }
516  int self_size() const { return self_size_; }
517  int security_token_id() const { return security_token_id_; }
518  bool painted_reachable() { return painted_ == kPaintReachable; }
519  bool not_painted_reachable_from_others() {
520    return painted_ != kPaintReachableFromOthers;
521  }
522  const List<HeapGraphEdge*>* children() const { return &children_; }
523  const List<HeapGraphEdge*>* retainers() const { return &retainers_; }
524  const List<HeapGraphPath*>* GetRetainingPaths();
525
526  void ClearPaint() { painted_ = kUnpainted; }
527  void CutEdges();
528  void MarkAsVisited() { visited_ = true; }
529  void PaintReachable() {
530    ASSERT(painted_ == kUnpainted);
531    painted_ = kPaintReachable;
532  }
533  void PaintReachableFromOthers() { painted_ = kPaintReachableFromOthers; }
534  void SetClosureReference(const char* name, HeapEntry* entry);
535  void SetElementReference(int index, HeapEntry* entry);
536  void SetPropertyReference(const char* name, HeapEntry* entry);
537  void SetAutoIndexReference(HeapEntry* entry);
538
539  int TotalSize();
540  int NonSharedTotalSize();
541
542  void Print(int max_depth, int indent);
543
544 private:
545  int CalculateTotalSize();
546  int CalculateNonSharedTotalSize();
547  void FindRetainingPaths(HeapEntry* node, CachedHeapGraphPath* prev_path);
548  void RemoveChild(HeapGraphEdge* edge);
549  void RemoveRetainer(HeapGraphEdge* edge);
550
551  const char* TypeAsString();
552
553  HeapSnapshot* snapshot_;
554  bool visited_;
555  Type type_;
556  const char* name_;
557  int next_auto_index_;
558  int self_size_;
559  int security_token_id_;
560  List<HeapGraphEdge*> children_;
561  List<HeapGraphEdge*> retainers_;
562  List<HeapGraphPath*> retaining_paths_;
563  int total_size_;
564  int non_shared_total_size_;
565  int painted_;
566
567  static const int kUnknownSize = -1;
568  static const int kUnpainted = 0;
569  static const int kPaintReachable = 1;
570  static const int kPaintReachableFromOthers = 2;
571
572  DISALLOW_IMPLICIT_CONSTRUCTORS(HeapEntry);
573};
574
575
576class HeapGraphPath {
577 public:
578  HeapGraphPath()
579      : path_(8) { }
580  explicit HeapGraphPath(const List<HeapGraphEdge*>& path);
581
582  void Add(HeapGraphEdge* edge) { path_.Add(edge); }
583  void Set(int index, HeapGraphEdge* edge) { path_[index] = edge; }
584  const List<HeapGraphEdge*>* path() const { return &path_; }
585
586  void Print();
587
588 private:
589  List<HeapGraphEdge*> path_;
590
591  DISALLOW_COPY_AND_ASSIGN(HeapGraphPath);
592};
593
594
595class HeapEntriesMap {
596 public:
597  HeapEntriesMap();
598  ~HeapEntriesMap();
599
600  void Alias(HeapObject* object, HeapEntry* entry);
601  void Apply(void (HeapEntry::*Func)(void));
602  template<class Visitor>
603  void Apply(Visitor* visitor);
604  HeapEntry* Map(HeapObject* object);
605  void Pair(HeapObject* object, HeapEntry* entry);
606
607 private:
608  INLINE(uint32_t Hash(HeapObject* object)) {
609    return static_cast<uint32_t>(reinterpret_cast<intptr_t>(object));
610  }
611  INLINE(static bool HeapObjectsMatch(void* key1, void* key2)) {
612    return key1 == key2;
613  }
614  INLINE(bool IsAlias(void* ptr)) {
615    return reinterpret_cast<intptr_t>(ptr) & kAliasTag;
616  }
617
618  static const intptr_t kAliasTag = 1;
619
620  HashMap entries_;
621
622  DISALLOW_COPY_AND_ASSIGN(HeapEntriesMap);
623};
624
625
626class HeapSnapshotsCollection;
627
628// HeapSnapshot represents a single heap snapshot. It is stored in
629// HeapSnapshotsCollection, which is also a factory for
630// HeapSnapshots. All HeapSnapshots share strings copied from JS heap
631// to be able to return them even if they were collected.
632// HeapSnapshotGenerator fills in a HeapSnapshot.
633class HeapSnapshot {
634 public:
635  HeapSnapshot(HeapSnapshotsCollection* collection,
636               const char* title,
637               unsigned uid);
638  void ClearPaint();
639  void CutObjectsFromForeignSecurityContexts();
640  HeapEntry* GetEntry(Object* object);
641  void SetClosureReference(
642      HeapEntry* parent, String* reference_name, Object* child);
643  void SetElementReference(HeapEntry* parent, int index, Object* child);
644  void SetPropertyReference(
645      HeapEntry* parent, String* reference_name, Object* child);
646
647  INLINE(const char* title() const) { return title_; }
648  INLINE(unsigned uid() const) { return uid_; }
649  const HeapEntry* const_root() const { return &root_; }
650  HeapEntry* root() { return &root_; }
651  template<class Visitor>
652  void IterateEntries(Visitor* visitor) { entries_.Apply(visitor); }
653
654  void Print(int max_depth);
655
656 private:
657  HeapEntry* AddEntry(HeapObject* object, HeapEntry::Type type) {
658    return AddEntry(object, type, "");
659  }
660  HeapEntry* AddEntry(
661      HeapObject* object, HeapEntry::Type type, const char* name);
662  void AddEntryAlias(HeapObject* object, HeapEntry* entry) {
663    entries_.Alias(object, entry);
664  }
665  HeapEntry* FindEntry(HeapObject* object) {
666    return entries_.Map(object);
667  }
668  int GetGlobalSecurityToken();
669  int GetObjectSecurityToken(HeapObject* obj);
670  static int GetObjectSize(HeapObject* obj);
671  static int CalculateNetworkSize(JSObject* obj);
672
673  HeapSnapshotsCollection* collection_;
674  const char* title_;
675  unsigned uid_;
676  HeapEntry root_;
677  // HeapObject* -> HeapEntry*
678  HeapEntriesMap entries_;
679
680  DISALLOW_COPY_AND_ASSIGN(HeapSnapshot);
681};
682
683
684class HeapSnapshotsCollection {
685 public:
686  HeapSnapshotsCollection();
687  ~HeapSnapshotsCollection();
688
689  HeapSnapshot* NewSnapshot(const char* name, unsigned uid);
690  List<HeapSnapshot*>* snapshots() { return &snapshots_; }
691  HeapSnapshot* GetSnapshot(unsigned uid);
692
693  const char* GetName(String* name) { return names_.GetName(name); }
694
695  TokenEnumerator* token_enumerator() { return token_enumerator_; }
696
697 private:
698  INLINE(static bool HeapSnapshotsMatch(void* key1, void* key2)) {
699    return key1 == key2;
700  }
701
702  List<HeapSnapshot*> snapshots_;
703  // uid -> HeapSnapshot*
704  HashMap snapshots_uids_;
705  StringsStorage names_;
706  TokenEnumerator* token_enumerator_;
707
708  DISALLOW_COPY_AND_ASSIGN(HeapSnapshotsCollection);
709};
710
711
712class HeapSnapshotGenerator {
713 public:
714  explicit HeapSnapshotGenerator(HeapSnapshot* snapshot);
715  void GenerateSnapshot();
716
717 private:
718  void ExtractReferences(HeapObject* obj);
719  void ExtractClosureReferences(JSObject* js_obj, HeapEntry* entry);
720  void ExtractPropertyReferences(JSObject* js_obj, HeapEntry* entry);
721  void ExtractElementReferences(JSObject* js_obj, HeapEntry* entry);
722
723  HeapSnapshot* snapshot_;
724
725  DISALLOW_COPY_AND_ASSIGN(HeapSnapshotGenerator);
726};
727
728} }  // namespace v8::internal
729
730#endif  // ENABLE_LOGGING_AND_PROFILING
731
732#endif  // V8_PROFILE_GENERATOR_H_
733