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1 /*
2  * Copyright (C) 2008 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 /*
18  * Preparation and completion of hprof data generation.  The output is
19  * written into two files and then combined.  This is necessary because
20  * we generate some of the data (strings and classes) while we dump the
21  * heap, and some analysis tools require that the class and string data
22  * appear first.
23  */
24 
25 #include "hprof.h"
26 
27 #include <cutils/open_memstream.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <stdio.h>
31 #include <string.h>
32 #include <sys/time.h>
33 #include <sys/uio.h>
34 #include <time.h>
35 #include <time.h>
36 #include <unistd.h>
37 
38 #include <set>
39 
40 #include "art_field-inl.h"
41 #include "base/logging.h"
42 #include "base/stringprintf.h"
43 #include "base/time_utils.h"
44 #include "base/unix_file/fd_file.h"
45 #include "class_linker.h"
46 #include "common_throws.h"
47 #include "debugger.h"
48 #include "dex_file-inl.h"
49 #include "gc_root.h"
50 #include "gc/accounting/heap_bitmap.h"
51 #include "gc/allocation_record.h"
52 #include "gc/heap.h"
53 #include "gc/space/space.h"
54 #include "globals.h"
55 #include "jdwp/jdwp.h"
56 #include "jdwp/jdwp_priv.h"
57 #include "mirror/class.h"
58 #include "mirror/class-inl.h"
59 #include "mirror/object-inl.h"
60 #include "os.h"
61 #include "safe_map.h"
62 #include "scoped_thread_state_change.h"
63 #include "thread_list.h"
64 
65 namespace art {
66 
67 namespace hprof {
68 
69 static constexpr bool kDirectStream = true;
70 
71 static constexpr uint32_t kHprofTime = 0;
72 static constexpr uint32_t kHprofNullThread = 0;
73 
74 static constexpr size_t kMaxObjectsPerSegment = 128;
75 static constexpr size_t kMaxBytesPerSegment = 4096;
76 
77 // The static field-name for the synthetic object generated to account for class static overhead.
78 static constexpr const char* kClassOverheadName = "$classOverhead";
79 
80 enum HprofTag {
81   HPROF_TAG_STRING = 0x01,
82   HPROF_TAG_LOAD_CLASS = 0x02,
83   HPROF_TAG_UNLOAD_CLASS = 0x03,
84   HPROF_TAG_STACK_FRAME = 0x04,
85   HPROF_TAG_STACK_TRACE = 0x05,
86   HPROF_TAG_ALLOC_SITES = 0x06,
87   HPROF_TAG_HEAP_SUMMARY = 0x07,
88   HPROF_TAG_START_THREAD = 0x0A,
89   HPROF_TAG_END_THREAD = 0x0B,
90   HPROF_TAG_HEAP_DUMP = 0x0C,
91   HPROF_TAG_HEAP_DUMP_SEGMENT = 0x1C,
92   HPROF_TAG_HEAP_DUMP_END = 0x2C,
93   HPROF_TAG_CPU_SAMPLES = 0x0D,
94   HPROF_TAG_CONTROL_SETTINGS = 0x0E,
95 };
96 
97 // Values for the first byte of HEAP_DUMP and HEAP_DUMP_SEGMENT records:
98 enum HprofHeapTag {
99   // Traditional.
100   HPROF_ROOT_UNKNOWN = 0xFF,
101   HPROF_ROOT_JNI_GLOBAL = 0x01,
102   HPROF_ROOT_JNI_LOCAL = 0x02,
103   HPROF_ROOT_JAVA_FRAME = 0x03,
104   HPROF_ROOT_NATIVE_STACK = 0x04,
105   HPROF_ROOT_STICKY_CLASS = 0x05,
106   HPROF_ROOT_THREAD_BLOCK = 0x06,
107   HPROF_ROOT_MONITOR_USED = 0x07,
108   HPROF_ROOT_THREAD_OBJECT = 0x08,
109   HPROF_CLASS_DUMP = 0x20,
110   HPROF_INSTANCE_DUMP = 0x21,
111   HPROF_OBJECT_ARRAY_DUMP = 0x22,
112   HPROF_PRIMITIVE_ARRAY_DUMP = 0x23,
113 
114   // Android.
115   HPROF_HEAP_DUMP_INFO = 0xfe,
116   HPROF_ROOT_INTERNED_STRING = 0x89,
117   HPROF_ROOT_FINALIZING = 0x8a,  // Obsolete.
118   HPROF_ROOT_DEBUGGER = 0x8b,
119   HPROF_ROOT_REFERENCE_CLEANUP = 0x8c,  // Obsolete.
120   HPROF_ROOT_VM_INTERNAL = 0x8d,
121   HPROF_ROOT_JNI_MONITOR = 0x8e,
122   HPROF_UNREACHABLE = 0x90,  // Obsolete.
123   HPROF_PRIMITIVE_ARRAY_NODATA_DUMP = 0xc3,  // Obsolete.
124 };
125 
126 enum HprofHeapId {
127   HPROF_HEAP_DEFAULT = 0,
128   HPROF_HEAP_ZYGOTE = 'Z',
129   HPROF_HEAP_APP = 'A',
130   HPROF_HEAP_IMAGE = 'I',
131 };
132 
133 enum HprofBasicType {
134   hprof_basic_object = 2,
135   hprof_basic_boolean = 4,
136   hprof_basic_char = 5,
137   hprof_basic_float = 6,
138   hprof_basic_double = 7,
139   hprof_basic_byte = 8,
140   hprof_basic_short = 9,
141   hprof_basic_int = 10,
142   hprof_basic_long = 11,
143 };
144 
145 typedef uint32_t HprofStringId;
146 typedef uint32_t HprofClassObjectId;
147 typedef uint32_t HprofClassSerialNumber;
148 typedef uint32_t HprofStackTraceSerialNumber;
149 typedef uint32_t HprofStackFrameId;
150 static constexpr HprofStackTraceSerialNumber kHprofNullStackTrace = 0;
151 
152 class EndianOutput {
153  public:
EndianOutput()154   EndianOutput() : length_(0), sum_length_(0), max_length_(0), started_(false) {}
~EndianOutput()155   virtual ~EndianOutput() {}
156 
StartNewRecord(uint8_t tag,uint32_t time)157   void StartNewRecord(uint8_t tag, uint32_t time) {
158     if (length_ > 0) {
159       EndRecord();
160     }
161     DCHECK_EQ(length_, 0U);
162     AddU1(tag);
163     AddU4(time);
164     AddU4(0xdeaddead);  // Length, replaced on flush.
165     started_ = true;
166   }
167 
EndRecord()168   void EndRecord() {
169     // Replace length in header.
170     if (started_) {
171       UpdateU4(sizeof(uint8_t) + sizeof(uint32_t),
172                length_ - sizeof(uint8_t) - 2 * sizeof(uint32_t));
173     }
174 
175     HandleEndRecord();
176 
177     sum_length_ += length_;
178     max_length_ = std::max(max_length_, length_);
179     length_ = 0;
180     started_ = false;
181   }
182 
AddU1(uint8_t value)183   void AddU1(uint8_t value) {
184     AddU1List(&value, 1);
185   }
AddU2(uint16_t value)186   void AddU2(uint16_t value) {
187     AddU2List(&value, 1);
188   }
AddU4(uint32_t value)189   void AddU4(uint32_t value) {
190     AddU4List(&value, 1);
191   }
192 
AddU8(uint64_t value)193   void AddU8(uint64_t value) {
194     AddU8List(&value, 1);
195   }
196 
AddObjectId(const mirror::Object * value)197   void AddObjectId(const mirror::Object* value) {
198     AddU4(PointerToLowMemUInt32(value));
199   }
200 
AddStackTraceSerialNumber(HprofStackTraceSerialNumber value)201   void AddStackTraceSerialNumber(HprofStackTraceSerialNumber value) {
202     AddU4(value);
203   }
204 
205   // The ID for the synthetic object generated to account for class static overhead.
AddClassStaticsId(const mirror::Class * value)206   void AddClassStaticsId(const mirror::Class* value) {
207     AddU4(1 | PointerToLowMemUInt32(value));
208   }
209 
AddJniGlobalRefId(jobject value)210   void AddJniGlobalRefId(jobject value) {
211     AddU4(PointerToLowMemUInt32(value));
212   }
213 
AddClassId(HprofClassObjectId value)214   void AddClassId(HprofClassObjectId value) {
215     AddU4(value);
216   }
217 
AddStringId(HprofStringId value)218   void AddStringId(HprofStringId value) {
219     AddU4(value);
220   }
221 
AddU1List(const uint8_t * values,size_t count)222   void AddU1List(const uint8_t* values, size_t count) {
223     HandleU1List(values, count);
224     length_ += count;
225   }
AddU2List(const uint16_t * values,size_t count)226   void AddU2List(const uint16_t* values, size_t count) {
227     HandleU2List(values, count);
228     length_ += count * sizeof(uint16_t);
229   }
AddU4List(const uint32_t * values,size_t count)230   void AddU4List(const uint32_t* values, size_t count) {
231     HandleU4List(values, count);
232     length_ += count * sizeof(uint32_t);
233   }
UpdateU4(size_t offset,uint32_t new_value ATTRIBUTE_UNUSED)234   virtual void UpdateU4(size_t offset, uint32_t new_value ATTRIBUTE_UNUSED) {
235     DCHECK_LE(offset, length_ - 4);
236   }
AddU8List(const uint64_t * values,size_t count)237   void AddU8List(const uint64_t* values, size_t count) {
238     HandleU8List(values, count);
239     length_ += count * sizeof(uint64_t);
240   }
241 
AddIdList(mirror::ObjectArray<mirror::Object> * values)242   void AddIdList(mirror::ObjectArray<mirror::Object>* values)
243       SHARED_REQUIRES(Locks::mutator_lock_) {
244     const int32_t length = values->GetLength();
245     for (int32_t i = 0; i < length; ++i) {
246       AddObjectId(values->GetWithoutChecks(i));
247     }
248   }
249 
AddUtf8String(const char * str)250   void AddUtf8String(const char* str) {
251     // The terminating NUL character is NOT written.
252     AddU1List((const uint8_t*)str, strlen(str));
253   }
254 
Length() const255   size_t Length() const {
256     return length_;
257   }
258 
SumLength() const259   size_t SumLength() const {
260     return sum_length_;
261   }
262 
MaxLength() const263   size_t MaxLength() const {
264     return max_length_;
265   }
266 
267  protected:
HandleU1List(const uint8_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)268   virtual void HandleU1List(const uint8_t* values ATTRIBUTE_UNUSED,
269                             size_t count ATTRIBUTE_UNUSED) {
270   }
HandleU2List(const uint16_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)271   virtual void HandleU2List(const uint16_t* values ATTRIBUTE_UNUSED,
272                             size_t count ATTRIBUTE_UNUSED) {
273   }
HandleU4List(const uint32_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)274   virtual void HandleU4List(const uint32_t* values ATTRIBUTE_UNUSED,
275                             size_t count ATTRIBUTE_UNUSED) {
276   }
HandleU8List(const uint64_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)277   virtual void HandleU8List(const uint64_t* values ATTRIBUTE_UNUSED,
278                             size_t count ATTRIBUTE_UNUSED) {
279   }
HandleEndRecord()280   virtual void HandleEndRecord() {
281   }
282 
283   size_t length_;      // Current record size.
284   size_t sum_length_;  // Size of all data.
285   size_t max_length_;  // Maximum seen length.
286   bool started_;       // Was StartRecord called?
287 };
288 
289 // This keeps things buffered until flushed.
290 class EndianOutputBuffered : public EndianOutput {
291  public:
EndianOutputBuffered(size_t reserve_size)292   explicit EndianOutputBuffered(size_t reserve_size) {
293     buffer_.reserve(reserve_size);
294   }
~EndianOutputBuffered()295   virtual ~EndianOutputBuffered() {}
296 
UpdateU4(size_t offset,uint32_t new_value)297   void UpdateU4(size_t offset, uint32_t new_value) OVERRIDE {
298     DCHECK_LE(offset, length_ - 4);
299     buffer_[offset + 0] = static_cast<uint8_t>((new_value >> 24) & 0xFF);
300     buffer_[offset + 1] = static_cast<uint8_t>((new_value >> 16) & 0xFF);
301     buffer_[offset + 2] = static_cast<uint8_t>((new_value >> 8)  & 0xFF);
302     buffer_[offset + 3] = static_cast<uint8_t>((new_value >> 0)  & 0xFF);
303   }
304 
305  protected:
HandleU1List(const uint8_t * values,size_t count)306   void HandleU1List(const uint8_t* values, size_t count) OVERRIDE {
307     DCHECK_EQ(length_, buffer_.size());
308     buffer_.insert(buffer_.end(), values, values + count);
309   }
310 
HandleU2List(const uint16_t * values,size_t count)311   void HandleU2List(const uint16_t* values, size_t count) OVERRIDE {
312     DCHECK_EQ(length_, buffer_.size());
313     for (size_t i = 0; i < count; ++i) {
314       uint16_t value = *values;
315       buffer_.push_back(static_cast<uint8_t>((value >> 8) & 0xFF));
316       buffer_.push_back(static_cast<uint8_t>((value >> 0) & 0xFF));
317       values++;
318     }
319   }
320 
HandleU4List(const uint32_t * values,size_t count)321   void HandleU4List(const uint32_t* values, size_t count) OVERRIDE {
322     DCHECK_EQ(length_, buffer_.size());
323     for (size_t i = 0; i < count; ++i) {
324       uint32_t value = *values;
325       buffer_.push_back(static_cast<uint8_t>((value >> 24) & 0xFF));
326       buffer_.push_back(static_cast<uint8_t>((value >> 16) & 0xFF));
327       buffer_.push_back(static_cast<uint8_t>((value >> 8)  & 0xFF));
328       buffer_.push_back(static_cast<uint8_t>((value >> 0)  & 0xFF));
329       values++;
330     }
331   }
332 
HandleU8List(const uint64_t * values,size_t count)333   void HandleU8List(const uint64_t* values, size_t count) OVERRIDE {
334     DCHECK_EQ(length_, buffer_.size());
335     for (size_t i = 0; i < count; ++i) {
336       uint64_t value = *values;
337       buffer_.push_back(static_cast<uint8_t>((value >> 56) & 0xFF));
338       buffer_.push_back(static_cast<uint8_t>((value >> 48) & 0xFF));
339       buffer_.push_back(static_cast<uint8_t>((value >> 40) & 0xFF));
340       buffer_.push_back(static_cast<uint8_t>((value >> 32) & 0xFF));
341       buffer_.push_back(static_cast<uint8_t>((value >> 24) & 0xFF));
342       buffer_.push_back(static_cast<uint8_t>((value >> 16) & 0xFF));
343       buffer_.push_back(static_cast<uint8_t>((value >> 8)  & 0xFF));
344       buffer_.push_back(static_cast<uint8_t>((value >> 0)  & 0xFF));
345       values++;
346     }
347   }
348 
HandleEndRecord()349   void HandleEndRecord() OVERRIDE {
350     DCHECK_EQ(buffer_.size(), length_);
351     if (kIsDebugBuild && started_) {
352       uint32_t stored_length =
353           static_cast<uint32_t>(buffer_[5]) << 24 |
354           static_cast<uint32_t>(buffer_[6]) << 16 |
355           static_cast<uint32_t>(buffer_[7]) << 8 |
356           static_cast<uint32_t>(buffer_[8]);
357       DCHECK_EQ(stored_length, length_ - sizeof(uint8_t) - 2 * sizeof(uint32_t));
358     }
359     HandleFlush(buffer_.data(), length_);
360     buffer_.clear();
361   }
362 
HandleFlush(const uint8_t * buffer ATTRIBUTE_UNUSED,size_t length ATTRIBUTE_UNUSED)363   virtual void HandleFlush(const uint8_t* buffer ATTRIBUTE_UNUSED, size_t length ATTRIBUTE_UNUSED) {
364   }
365 
366   std::vector<uint8_t> buffer_;
367 };
368 
369 class FileEndianOutput FINAL : public EndianOutputBuffered {
370  public:
FileEndianOutput(File * fp,size_t reserved_size)371   FileEndianOutput(File* fp, size_t reserved_size)
372       : EndianOutputBuffered(reserved_size), fp_(fp), errors_(false) {
373     DCHECK(fp != nullptr);
374   }
~FileEndianOutput()375   ~FileEndianOutput() {
376   }
377 
Errors()378   bool Errors() {
379     return errors_;
380   }
381 
382  protected:
HandleFlush(const uint8_t * buffer,size_t length)383   void HandleFlush(const uint8_t* buffer, size_t length) OVERRIDE {
384     if (!errors_) {
385       errors_ = !fp_->WriteFully(buffer, length);
386     }
387   }
388 
389  private:
390   File* fp_;
391   bool errors_;
392 };
393 
394 class NetStateEndianOutput FINAL : public EndianOutputBuffered {
395  public:
NetStateEndianOutput(JDWP::JdwpNetStateBase * net_state,size_t reserved_size)396   NetStateEndianOutput(JDWP::JdwpNetStateBase* net_state, size_t reserved_size)
397       : EndianOutputBuffered(reserved_size), net_state_(net_state) {
398     DCHECK(net_state != nullptr);
399   }
~NetStateEndianOutput()400   ~NetStateEndianOutput() {}
401 
402  protected:
HandleFlush(const uint8_t * buffer,size_t length)403   void HandleFlush(const uint8_t* buffer, size_t length) OVERRIDE {
404     std::vector<iovec> iov;
405     iov.push_back(iovec());
406     iov[0].iov_base = const_cast<void*>(reinterpret_cast<const void*>(buffer));
407     iov[0].iov_len = length;
408     net_state_->WriteBufferedPacketLocked(iov);
409   }
410 
411  private:
412   JDWP::JdwpNetStateBase* net_state_;
413 };
414 
415 #define __ output_->
416 
417 class Hprof : public SingleRootVisitor {
418  public:
Hprof(const char * output_filename,int fd,bool direct_to_ddms)419   Hprof(const char* output_filename, int fd, bool direct_to_ddms)
420       : filename_(output_filename),
421         fd_(fd),
422         direct_to_ddms_(direct_to_ddms) {
423     LOG(INFO) << "hprof: heap dump \"" << filename_ << "\" starting...";
424   }
425 
Dump()426   void Dump()
427     REQUIRES(Locks::mutator_lock_)
428     REQUIRES(!Locks::heap_bitmap_lock_, !Locks::alloc_tracker_lock_) {
429     {
430       MutexLock mu(Thread::Current(), *Locks::alloc_tracker_lock_);
431       if (Runtime::Current()->GetHeap()->IsAllocTrackingEnabled()) {
432         PopulateAllocationTrackingTraces();
433       }
434     }
435 
436     // First pass to measure the size of the dump.
437     size_t overall_size;
438     size_t max_length;
439     {
440       EndianOutput count_output;
441       output_ = &count_output;
442       ProcessHeap(false);
443       overall_size = count_output.SumLength();
444       max_length = count_output.MaxLength();
445       output_ = nullptr;
446     }
447 
448     bool okay;
449     if (direct_to_ddms_) {
450       if (kDirectStream) {
451         okay = DumpToDdmsDirect(overall_size, max_length, CHUNK_TYPE("HPDS"));
452       } else {
453         okay = DumpToDdmsBuffered(overall_size, max_length);
454       }
455     } else {
456       okay = DumpToFile(overall_size, max_length);
457     }
458 
459     if (okay) {
460       const uint64_t duration = NanoTime() - start_ns_;
461       LOG(INFO) << "hprof: heap dump completed (" << PrettySize(RoundUp(overall_size, KB))
462                 << ") in " << PrettyDuration(duration)
463                 << " objects " << total_objects_
464                 << " objects with stack traces " << total_objects_with_stack_trace_;
465     }
466   }
467 
468  private:
VisitObjectCallback(mirror::Object * obj,void * arg)469   static void VisitObjectCallback(mirror::Object* obj, void* arg)
470       SHARED_REQUIRES(Locks::mutator_lock_) {
471     DCHECK(obj != nullptr);
472     DCHECK(arg != nullptr);
473     reinterpret_cast<Hprof*>(arg)->DumpHeapObject(obj);
474   }
475 
476   void DumpHeapObject(mirror::Object* obj)
477       SHARED_REQUIRES(Locks::mutator_lock_);
478 
479   void DumpHeapClass(mirror::Class* klass)
480       SHARED_REQUIRES(Locks::mutator_lock_);
481 
482   void DumpHeapArray(mirror::Array* obj, mirror::Class* klass)
483       SHARED_REQUIRES(Locks::mutator_lock_);
484 
485   void DumpHeapInstanceObject(mirror::Object* obj, mirror::Class* klass)
486       SHARED_REQUIRES(Locks::mutator_lock_);
487 
ProcessHeap(bool header_first)488   void ProcessHeap(bool header_first)
489       REQUIRES(Locks::mutator_lock_) {
490     // Reset current heap and object count.
491     current_heap_ = HPROF_HEAP_DEFAULT;
492     objects_in_segment_ = 0;
493 
494     if (header_first) {
495       ProcessHeader(true);
496       ProcessBody();
497     } else {
498       ProcessBody();
499       ProcessHeader(false);
500     }
501   }
502 
ProcessBody()503   void ProcessBody() REQUIRES(Locks::mutator_lock_) {
504     Runtime* const runtime = Runtime::Current();
505     // Walk the roots and the heap.
506     output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_SEGMENT, kHprofTime);
507 
508     simple_roots_.clear();
509     runtime->VisitRoots(this);
510     runtime->VisitImageRoots(this);
511     runtime->GetHeap()->VisitObjectsPaused(VisitObjectCallback, this);
512 
513     output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_END, kHprofTime);
514     output_->EndRecord();
515   }
516 
ProcessHeader(bool string_first)517   void ProcessHeader(bool string_first) REQUIRES(Locks::mutator_lock_) {
518     // Write the header.
519     WriteFixedHeader();
520     // Write the string and class tables, and any stack traces, to the header.
521     // (jhat requires that these appear before any of the data in the body that refers to them.)
522     // jhat also requires the string table appear before class table and stack traces.
523     // However, WriteStackTraces() can modify the string table, so it's necessary to call
524     // WriteStringTable() last in the first pass, to compute the correct length of the output.
525     if (string_first) {
526       WriteStringTable();
527     }
528     WriteClassTable();
529     WriteStackTraces();
530     if (!string_first) {
531       WriteStringTable();
532     }
533     output_->EndRecord();
534   }
535 
WriteClassTable()536   void WriteClassTable() SHARED_REQUIRES(Locks::mutator_lock_) {
537     for (const auto& p : classes_) {
538       mirror::Class* c = p.first;
539       HprofClassSerialNumber sn = p.second;
540       CHECK(c != nullptr);
541       output_->StartNewRecord(HPROF_TAG_LOAD_CLASS, kHprofTime);
542       // LOAD CLASS format:
543       // U4: class serial number (always > 0)
544       // ID: class object ID. We use the address of the class object structure as its ID.
545       // U4: stack trace serial number
546       // ID: class name string ID
547       __ AddU4(sn);
548       __ AddObjectId(c);
549       __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(c));
550       __ AddStringId(LookupClassNameId(c));
551     }
552   }
553 
WriteStringTable()554   void WriteStringTable() {
555     for (const std::pair<std::string, HprofStringId>& p : strings_) {
556       const std::string& string = p.first;
557       const size_t id = p.second;
558 
559       output_->StartNewRecord(HPROF_TAG_STRING, kHprofTime);
560 
561       // STRING format:
562       // ID:  ID for this string
563       // U1*: UTF8 characters for string (NOT null terminated)
564       //      (the record format encodes the length)
565       __ AddU4(id);
566       __ AddUtf8String(string.c_str());
567     }
568   }
569 
StartNewHeapDumpSegment()570   void StartNewHeapDumpSegment() {
571     // This flushes the old segment and starts a new one.
572     output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_SEGMENT, kHprofTime);
573     objects_in_segment_ = 0;
574     // Starting a new HEAP_DUMP resets the heap to default.
575     current_heap_ = HPROF_HEAP_DEFAULT;
576   }
577 
CheckHeapSegmentConstraints()578   void CheckHeapSegmentConstraints() {
579     if (objects_in_segment_ >= kMaxObjectsPerSegment || output_->Length() >= kMaxBytesPerSegment) {
580       StartNewHeapDumpSegment();
581     }
582   }
583 
584   void VisitRoot(mirror::Object* obj, const RootInfo& root_info)
585       OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_);
586   void MarkRootObject(const mirror::Object* obj, jobject jni_obj, HprofHeapTag heap_tag,
587                       uint32_t thread_serial);
588 
LookupClassId(mirror::Class * c)589   HprofClassObjectId LookupClassId(mirror::Class* c) SHARED_REQUIRES(Locks::mutator_lock_) {
590     if (c != nullptr) {
591       auto it = classes_.find(c);
592       if (it == classes_.end()) {
593         // first time to see this class
594         HprofClassSerialNumber sn = next_class_serial_number_++;
595         classes_.Put(c, sn);
596         // Make sure that we've assigned a string ID for this class' name
597         LookupClassNameId(c);
598       }
599     }
600     return PointerToLowMemUInt32(c);
601   }
602 
LookupStackTraceSerialNumber(const mirror::Object * obj)603   HprofStackTraceSerialNumber LookupStackTraceSerialNumber(const mirror::Object* obj)
604       SHARED_REQUIRES(Locks::mutator_lock_) {
605     auto r = allocation_records_.find(obj);
606     if (r == allocation_records_.end()) {
607       return kHprofNullStackTrace;
608     } else {
609       const gc::AllocRecordStackTrace* trace = r->second;
610       auto result = traces_.find(trace);
611       CHECK(result != traces_.end());
612       return result->second;
613     }
614   }
615 
LookupStringId(mirror::String * string)616   HprofStringId LookupStringId(mirror::String* string) SHARED_REQUIRES(Locks::mutator_lock_) {
617     return LookupStringId(string->ToModifiedUtf8());
618   }
619 
LookupStringId(const char * string)620   HprofStringId LookupStringId(const char* string) {
621     return LookupStringId(std::string(string));
622   }
623 
LookupStringId(const std::string & string)624   HprofStringId LookupStringId(const std::string& string) {
625     auto it = strings_.find(string);
626     if (it != strings_.end()) {
627       return it->second;
628     }
629     HprofStringId id = next_string_id_++;
630     strings_.Put(string, id);
631     return id;
632   }
633 
LookupClassNameId(mirror::Class * c)634   HprofStringId LookupClassNameId(mirror::Class* c) SHARED_REQUIRES(Locks::mutator_lock_) {
635     return LookupStringId(PrettyDescriptor(c));
636   }
637 
WriteFixedHeader()638   void WriteFixedHeader() {
639     // Write the file header.
640     // U1: NUL-terminated magic string.
641     const char magic[] = "JAVA PROFILE 1.0.3";
642     __ AddU1List(reinterpret_cast<const uint8_t*>(magic), sizeof(magic));
643 
644     // U4: size of identifiers.  We're using addresses as IDs and our heap references are stored
645     // as uint32_t.
646     // Note of warning: hprof-conv hard-codes the size of identifiers to 4.
647     static_assert(sizeof(mirror::HeapReference<mirror::Object>) == sizeof(uint32_t),
648                   "Unexpected HeapReference size");
649     __ AddU4(sizeof(uint32_t));
650 
651     // The current time, in milliseconds since 0:00 GMT, 1/1/70.
652     timeval now;
653     const uint64_t nowMs = (gettimeofday(&now, nullptr) < 0) ? 0 :
654         (uint64_t)now.tv_sec * 1000 + now.tv_usec / 1000;
655     // TODO: It seems it would be correct to use U8.
656     // U4: high word of the 64-bit time.
657     __ AddU4(static_cast<uint32_t>(nowMs >> 32));
658     // U4: low word of the 64-bit time.
659     __ AddU4(static_cast<uint32_t>(nowMs & 0xFFFFFFFF));
660   }
661 
WriteStackTraces()662   void WriteStackTraces() SHARED_REQUIRES(Locks::mutator_lock_) {
663     // Write a dummy stack trace record so the analysis tools don't freak out.
664     output_->StartNewRecord(HPROF_TAG_STACK_TRACE, kHprofTime);
665     __ AddStackTraceSerialNumber(kHprofNullStackTrace);
666     __ AddU4(kHprofNullThread);
667     __ AddU4(0);    // no frames
668 
669     // TODO: jhat complains "WARNING: Stack trace not found for serial # -1", but no trace should
670     // have -1 as its serial number (as long as HprofStackTraceSerialNumber doesn't overflow).
671     for (const auto& it : traces_) {
672       const gc::AllocRecordStackTrace* trace = it.first;
673       HprofStackTraceSerialNumber trace_sn = it.second;
674       size_t depth = trace->GetDepth();
675 
676       // First write stack frames of the trace
677       for (size_t i = 0; i < depth; ++i) {
678         const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
679         ArtMethod* method = frame->GetMethod();
680         CHECK(method != nullptr);
681         output_->StartNewRecord(HPROF_TAG_STACK_FRAME, kHprofTime);
682         // STACK FRAME format:
683         // ID: stack frame ID. We use the address of the AllocRecordStackTraceElement object as its ID.
684         // ID: method name string ID
685         // ID: method signature string ID
686         // ID: source file name string ID
687         // U4: class serial number
688         // U4: >0, line number; 0, no line information available; -1, unknown location
689         auto frame_result = frames_.find(frame);
690         CHECK(frame_result != frames_.end());
691         __ AddU4(frame_result->second);
692         __ AddStringId(LookupStringId(method->GetName()));
693         __ AddStringId(LookupStringId(method->GetSignature().ToString()));
694         const char* source_file = method->GetDeclaringClassSourceFile();
695         if (source_file == nullptr) {
696           source_file = "";
697         }
698         __ AddStringId(LookupStringId(source_file));
699         auto class_result = classes_.find(method->GetDeclaringClass());
700         CHECK(class_result != classes_.end());
701         __ AddU4(class_result->second);
702         __ AddU4(frame->ComputeLineNumber());
703       }
704 
705       // Then write the trace itself
706       output_->StartNewRecord(HPROF_TAG_STACK_TRACE, kHprofTime);
707       // STACK TRACE format:
708       // U4: stack trace serial number. We use the address of the AllocRecordStackTrace object as its serial number.
709       // U4: thread serial number. We use Thread::GetTid().
710       // U4: number of frames
711       // [ID]*: series of stack frame ID's
712       __ AddStackTraceSerialNumber(trace_sn);
713       __ AddU4(trace->GetTid());
714       __ AddU4(depth);
715       for (size_t i = 0; i < depth; ++i) {
716         const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
717         auto frame_result = frames_.find(frame);
718         CHECK(frame_result != frames_.end());
719         __ AddU4(frame_result->second);
720       }
721     }
722   }
723 
DumpToDdmsBuffered(size_t overall_size ATTRIBUTE_UNUSED,size_t max_length ATTRIBUTE_UNUSED)724   bool DumpToDdmsBuffered(size_t overall_size ATTRIBUTE_UNUSED, size_t max_length ATTRIBUTE_UNUSED)
725       REQUIRES(Locks::mutator_lock_) {
726     LOG(FATAL) << "Unimplemented";
727     UNREACHABLE();
728     //        // Send the data off to DDMS.
729     //        iovec iov[2];
730     //        iov[0].iov_base = header_data_ptr_;
731     //        iov[0].iov_len = header_data_size_;
732     //        iov[1].iov_base = body_data_ptr_;
733     //        iov[1].iov_len = body_data_size_;
734     //        Dbg::DdmSendChunkV(CHUNK_TYPE("HPDS"), iov, 2);
735   }
736 
DumpToFile(size_t overall_size,size_t max_length)737   bool DumpToFile(size_t overall_size, size_t max_length)
738       REQUIRES(Locks::mutator_lock_) {
739     // Where exactly are we writing to?
740     int out_fd;
741     if (fd_ >= 0) {
742       out_fd = dup(fd_);
743       if (out_fd < 0) {
744         ThrowRuntimeException("Couldn't dump heap; dup(%d) failed: %s", fd_, strerror(errno));
745         return false;
746       }
747     } else {
748       out_fd = open(filename_.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0644);
749       if (out_fd < 0) {
750         ThrowRuntimeException("Couldn't dump heap; open(\"%s\") failed: %s", filename_.c_str(),
751                               strerror(errno));
752         return false;
753       }
754     }
755 
756     std::unique_ptr<File> file(new File(out_fd, filename_, true));
757     bool okay;
758     {
759       FileEndianOutput file_output(file.get(), max_length);
760       output_ = &file_output;
761       ProcessHeap(true);
762       okay = !file_output.Errors();
763 
764       if (okay) {
765         // Check for expected size. Output is expected to be less-or-equal than first phase, see
766         // b/23521263.
767         DCHECK_LE(file_output.SumLength(), overall_size);
768       }
769       output_ = nullptr;
770     }
771 
772     if (okay) {
773       okay = file->FlushCloseOrErase() == 0;
774     } else {
775       file->Erase();
776     }
777     if (!okay) {
778       std::string msg(StringPrintf("Couldn't dump heap; writing \"%s\" failed: %s",
779                                    filename_.c_str(), strerror(errno)));
780       ThrowRuntimeException("%s", msg.c_str());
781       LOG(ERROR) << msg;
782     }
783 
784     return okay;
785   }
786 
DumpToDdmsDirect(size_t overall_size,size_t max_length,uint32_t chunk_type)787   bool DumpToDdmsDirect(size_t overall_size, size_t max_length, uint32_t chunk_type)
788       REQUIRES(Locks::mutator_lock_) {
789     CHECK(direct_to_ddms_);
790     JDWP::JdwpState* state = Dbg::GetJdwpState();
791     CHECK(state != nullptr);
792     JDWP::JdwpNetStateBase* net_state = state->netState;
793     CHECK(net_state != nullptr);
794 
795     // Hold the socket lock for the whole time since we want this to be atomic.
796     MutexLock mu(Thread::Current(), *net_state->GetSocketLock());
797 
798     // Prepare the Ddms chunk.
799     constexpr size_t kChunkHeaderSize = kJDWPHeaderLen + 8;
800     uint8_t chunk_header[kChunkHeaderSize] = { 0 };
801     state->SetupChunkHeader(chunk_type, overall_size, kChunkHeaderSize, chunk_header);
802 
803     // Prepare the output and send the chunk header.
804     NetStateEndianOutput net_output(net_state, max_length);
805     output_ = &net_output;
806     net_output.AddU1List(chunk_header, kChunkHeaderSize);
807 
808     // Write the dump.
809     ProcessHeap(true);
810 
811     // Check for expected size. See DumpToFile for comment.
812     DCHECK_LE(net_output.SumLength(), overall_size + kChunkHeaderSize);
813     output_ = nullptr;
814 
815     return true;
816   }
817 
PopulateAllocationTrackingTraces()818   void PopulateAllocationTrackingTraces()
819       REQUIRES(Locks::mutator_lock_, Locks::alloc_tracker_lock_) {
820     gc::AllocRecordObjectMap* records = Runtime::Current()->GetHeap()->GetAllocationRecords();
821     CHECK(records != nullptr);
822     HprofStackTraceSerialNumber next_trace_sn = kHprofNullStackTrace + 1;
823     HprofStackFrameId next_frame_id = 0;
824     size_t count = 0;
825 
826     for (auto it = records->Begin(), end = records->End(); it != end; ++it) {
827       const mirror::Object* obj = it->first.Read();
828       if (obj == nullptr) {
829         continue;
830       }
831       ++count;
832       const gc::AllocRecordStackTrace* trace = it->second.GetStackTrace();
833 
834       // Copy the pair into a real hash map to speed up look up.
835       auto records_result = allocation_records_.emplace(obj, trace);
836       // The insertion should always succeed, i.e. no duplicate object pointers in "records"
837       CHECK(records_result.second);
838 
839       // Generate serial numbers for traces, and IDs for frames.
840       auto traces_result = traces_.find(trace);
841       if (traces_result == traces_.end()) {
842         traces_.emplace(trace, next_trace_sn++);
843         // only check frames if the trace is newly discovered
844         for (size_t i = 0, depth = trace->GetDepth(); i < depth; ++i) {
845           const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
846           auto frames_result = frames_.find(frame);
847           if (frames_result == frames_.end()) {
848             frames_.emplace(frame, next_frame_id++);
849           }
850         }
851       }
852     }
853     CHECK_EQ(traces_.size(), next_trace_sn - kHprofNullStackTrace - 1);
854     CHECK_EQ(frames_.size(), next_frame_id);
855     total_objects_with_stack_trace_ = count;
856   }
857 
858   // If direct_to_ddms_ is set, "filename_" and "fd" will be ignored.
859   // Otherwise, "filename_" must be valid, though if "fd" >= 0 it will
860   // only be used for debug messages.
861   std::string filename_;
862   int fd_;
863   bool direct_to_ddms_;
864 
865   uint64_t start_ns_ = NanoTime();
866 
867   EndianOutput* output_ = nullptr;
868 
869   HprofHeapId current_heap_ = HPROF_HEAP_DEFAULT;  // Which heap we're currently dumping.
870   size_t objects_in_segment_ = 0;
871 
872   size_t total_objects_ = 0u;
873   size_t total_objects_with_stack_trace_ = 0u;
874 
875   HprofStringId next_string_id_ = 0x400000;
876   SafeMap<std::string, HprofStringId> strings_;
877   HprofClassSerialNumber next_class_serial_number_ = 1;
878   SafeMap<mirror::Class*, HprofClassSerialNumber> classes_;
879 
880   std::unordered_map<const gc::AllocRecordStackTrace*, HprofStackTraceSerialNumber,
881                      gc::HashAllocRecordTypesPtr<gc::AllocRecordStackTrace>,
882                      gc::EqAllocRecordTypesPtr<gc::AllocRecordStackTrace>> traces_;
883   std::unordered_map<const gc::AllocRecordStackTraceElement*, HprofStackFrameId,
884                      gc::HashAllocRecordTypesPtr<gc::AllocRecordStackTraceElement>,
885                      gc::EqAllocRecordTypesPtr<gc::AllocRecordStackTraceElement>> frames_;
886   std::unordered_map<const mirror::Object*, const gc::AllocRecordStackTrace*> allocation_records_;
887 
888   // Set used to keep track of what simple root records we have already
889   // emitted, to avoid emitting duplicate entries. The simple root records are
890   // those that contain no other information than the root type and the object
891   // id. A pair of root type and object id is packed into a uint64_t, with
892   // the root type in the upper 32 bits and the object id in the lower 32
893   // bits.
894   std::unordered_set<uint64_t> simple_roots_;
895 
896   friend class GcRootVisitor;
897   DISALLOW_COPY_AND_ASSIGN(Hprof);
898 };
899 
SignatureToBasicTypeAndSize(const char * sig,size_t * size_out)900 static HprofBasicType SignatureToBasicTypeAndSize(const char* sig, size_t* size_out) {
901   char c = sig[0];
902   HprofBasicType ret;
903   size_t size;
904 
905   switch (c) {
906     case '[':
907     case 'L':
908       ret = hprof_basic_object;
909       size = 4;
910       break;
911     case 'Z':
912       ret = hprof_basic_boolean;
913       size = 1;
914       break;
915     case 'C':
916       ret = hprof_basic_char;
917       size = 2;
918       break;
919     case 'F':
920       ret = hprof_basic_float;
921       size = 4;
922       break;
923     case 'D':
924       ret = hprof_basic_double;
925       size = 8;
926       break;
927     case 'B':
928       ret = hprof_basic_byte;
929       size = 1;
930       break;
931     case 'S':
932       ret = hprof_basic_short;
933       size = 2;
934       break;
935     case 'I':
936       ret = hprof_basic_int;
937       size = 4;
938       break;
939     case 'J':
940       ret = hprof_basic_long;
941       size = 8;
942       break;
943     default:
944       LOG(FATAL) << "UNREACHABLE";
945       UNREACHABLE();
946   }
947 
948   if (size_out != nullptr) {
949     *size_out = size;
950   }
951 
952   return ret;
953 }
954 
955 // Always called when marking objects, but only does
956 // something when ctx->gc_scan_state_ is non-zero, which is usually
957 // only true when marking the root set or unreachable
958 // objects.  Used to add rootset references to obj.
MarkRootObject(const mirror::Object * obj,jobject jni_obj,HprofHeapTag heap_tag,uint32_t thread_serial)959 void Hprof::MarkRootObject(const mirror::Object* obj, jobject jni_obj, HprofHeapTag heap_tag,
960                            uint32_t thread_serial) {
961   if (heap_tag == 0) {
962     return;
963   }
964 
965   CheckHeapSegmentConstraints();
966 
967   switch (heap_tag) {
968     // ID: object ID
969     case HPROF_ROOT_UNKNOWN:
970     case HPROF_ROOT_STICKY_CLASS:
971     case HPROF_ROOT_MONITOR_USED:
972     case HPROF_ROOT_INTERNED_STRING:
973     case HPROF_ROOT_DEBUGGER:
974     case HPROF_ROOT_VM_INTERNAL: {
975       uint64_t key = (static_cast<uint64_t>(heap_tag) << 32) | PointerToLowMemUInt32(obj);
976       if (simple_roots_.insert(key).second) {
977         __ AddU1(heap_tag);
978         __ AddObjectId(obj);
979       }
980       break;
981     }
982 
983       // ID: object ID
984       // ID: JNI global ref ID
985     case HPROF_ROOT_JNI_GLOBAL:
986       __ AddU1(heap_tag);
987       __ AddObjectId(obj);
988       __ AddJniGlobalRefId(jni_obj);
989       break;
990 
991       // ID: object ID
992       // U4: thread serial number
993       // U4: frame number in stack trace (-1 for empty)
994     case HPROF_ROOT_JNI_LOCAL:
995     case HPROF_ROOT_JNI_MONITOR:
996     case HPROF_ROOT_JAVA_FRAME:
997       __ AddU1(heap_tag);
998       __ AddObjectId(obj);
999       __ AddU4(thread_serial);
1000       __ AddU4((uint32_t)-1);
1001       break;
1002 
1003       // ID: object ID
1004       // U4: thread serial number
1005     case HPROF_ROOT_NATIVE_STACK:
1006     case HPROF_ROOT_THREAD_BLOCK:
1007       __ AddU1(heap_tag);
1008       __ AddObjectId(obj);
1009       __ AddU4(thread_serial);
1010       break;
1011 
1012       // ID: thread object ID
1013       // U4: thread serial number
1014       // U4: stack trace serial number
1015     case HPROF_ROOT_THREAD_OBJECT:
1016       __ AddU1(heap_tag);
1017       __ AddObjectId(obj);
1018       __ AddU4(thread_serial);
1019       __ AddU4((uint32_t)-1);    // xxx
1020       break;
1021 
1022     case HPROF_CLASS_DUMP:
1023     case HPROF_INSTANCE_DUMP:
1024     case HPROF_OBJECT_ARRAY_DUMP:
1025     case HPROF_PRIMITIVE_ARRAY_DUMP:
1026     case HPROF_HEAP_DUMP_INFO:
1027     case HPROF_PRIMITIVE_ARRAY_NODATA_DUMP:
1028       // Ignored.
1029       break;
1030 
1031     case HPROF_ROOT_FINALIZING:
1032     case HPROF_ROOT_REFERENCE_CLEANUP:
1033     case HPROF_UNREACHABLE:
1034       LOG(FATAL) << "obsolete tag " << static_cast<int>(heap_tag);
1035       break;
1036   }
1037 
1038   ++objects_in_segment_;
1039 }
1040 
1041 // Use for visiting the GcRoots held live by ArtFields, ArtMethods, and ClassLoaders.
1042 class GcRootVisitor {
1043  public:
GcRootVisitor(Hprof * hprof)1044   explicit GcRootVisitor(Hprof* hprof) : hprof_(hprof) {}
1045 
operator ()(mirror::Object * obj ATTRIBUTE_UNUSED,MemberOffset offset ATTRIBUTE_UNUSED,bool is_static ATTRIBUTE_UNUSED) const1046   void operator()(mirror::Object* obj ATTRIBUTE_UNUSED,
1047                   MemberOffset offset ATTRIBUTE_UNUSED,
1048                   bool is_static ATTRIBUTE_UNUSED) const {}
1049 
1050   // Note that these don't have read barriers. Its OK however since the GC is guaranteed to not be
1051   // running during the hprof dumping process.
VisitRootIfNonNull(mirror::CompressedReference<mirror::Object> * root) const1052   void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
1053       SHARED_REQUIRES(Locks::mutator_lock_) {
1054     if (!root->IsNull()) {
1055       VisitRoot(root);
1056     }
1057   }
1058 
VisitRoot(mirror::CompressedReference<mirror::Object> * root) const1059   void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
1060       SHARED_REQUIRES(Locks::mutator_lock_) {
1061     mirror::Object* obj = root->AsMirrorPtr();
1062     // The two cases are either classes or dex cache arrays. If it is a dex cache array, then use
1063     // VM internal. Otherwise the object is a declaring class of an ArtField or ArtMethod or a
1064     // class from a ClassLoader.
1065     hprof_->VisitRoot(obj, RootInfo(obj->IsClass() ? kRootStickyClass : kRootVMInternal));
1066   }
1067 
1068 
1069  private:
1070   Hprof* const hprof_;
1071 };
1072 
DumpHeapObject(mirror::Object * obj)1073 void Hprof::DumpHeapObject(mirror::Object* obj) {
1074   // Ignore classes that are retired.
1075   if (obj->IsClass() && obj->AsClass()->IsRetired()) {
1076     return;
1077   }
1078 
1079   ++total_objects_;
1080 
1081   GcRootVisitor visitor(this);
1082   obj->VisitReferences(visitor, VoidFunctor());
1083 
1084   gc::Heap* const heap = Runtime::Current()->GetHeap();
1085   const gc::space::ContinuousSpace* const space = heap->FindContinuousSpaceFromObject(obj, true);
1086   HprofHeapId heap_type = HPROF_HEAP_APP;
1087   if (space != nullptr) {
1088     if (space->IsZygoteSpace()) {
1089       heap_type = HPROF_HEAP_ZYGOTE;
1090     } else if (space->IsImageSpace()) {
1091       heap_type = HPROF_HEAP_IMAGE;
1092     }
1093   } else {
1094     const auto* los = heap->GetLargeObjectsSpace();
1095     if (los->Contains(obj) && los->IsZygoteLargeObject(Thread::Current(), obj)) {
1096       heap_type = HPROF_HEAP_ZYGOTE;
1097     }
1098   }
1099   CheckHeapSegmentConstraints();
1100 
1101   if (heap_type != current_heap_) {
1102     HprofStringId nameId;
1103 
1104     // This object is in a different heap than the current one.
1105     // Emit a HEAP_DUMP_INFO tag to change heaps.
1106     __ AddU1(HPROF_HEAP_DUMP_INFO);
1107     __ AddU4(static_cast<uint32_t>(heap_type));   // uint32_t: heap type
1108     switch (heap_type) {
1109     case HPROF_HEAP_APP:
1110       nameId = LookupStringId("app");
1111       break;
1112     case HPROF_HEAP_ZYGOTE:
1113       nameId = LookupStringId("zygote");
1114       break;
1115     case HPROF_HEAP_IMAGE:
1116       nameId = LookupStringId("image");
1117       break;
1118     default:
1119       // Internal error
1120       LOG(ERROR) << "Unexpected desiredHeap";
1121       nameId = LookupStringId("<ILLEGAL>");
1122       break;
1123     }
1124     __ AddStringId(nameId);
1125     current_heap_ = heap_type;
1126   }
1127 
1128   mirror::Class* c = obj->GetClass();
1129   if (c == nullptr) {
1130     // This object will bother HprofReader, because it has a null
1131     // class, so just don't dump it. It could be
1132     // gDvm.unlinkedJavaLangClass or it could be an object just
1133     // allocated which hasn't been initialized yet.
1134   } else {
1135     if (obj->IsClass()) {
1136       DumpHeapClass(obj->AsClass());
1137     } else if (c->IsArrayClass()) {
1138       DumpHeapArray(obj->AsArray(), c);
1139     } else {
1140       DumpHeapInstanceObject(obj, c);
1141     }
1142   }
1143 
1144   ++objects_in_segment_;
1145 }
1146 
DumpHeapClass(mirror::Class * klass)1147 void Hprof::DumpHeapClass(mirror::Class* klass) {
1148   if (!klass->IsLoaded() && !klass->IsErroneous()) {
1149     // Class is allocated but not yet loaded: we cannot access its fields or super class.
1150     return;
1151   }
1152   const size_t num_static_fields = klass->NumStaticFields();
1153   // Total class size including embedded IMT, embedded vtable, and static fields.
1154   const size_t class_size = klass->GetClassSize();
1155   // Class size excluding static fields (relies on reference fields being the first static fields).
1156   const size_t class_size_without_overhead = sizeof(mirror::Class);
1157   CHECK_LE(class_size_without_overhead, class_size);
1158   const size_t overhead_size = class_size - class_size_without_overhead;
1159 
1160   if (overhead_size != 0) {
1161     // Create a byte array to reflect the allocation of the
1162     // StaticField array at the end of this class.
1163     __ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
1164     __ AddClassStaticsId(klass);
1165     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(klass));
1166     __ AddU4(overhead_size);
1167     __ AddU1(hprof_basic_byte);
1168     for (size_t i = 0; i < overhead_size; ++i) {
1169       __ AddU1(0);
1170     }
1171   }
1172 
1173   __ AddU1(HPROF_CLASS_DUMP);
1174   __ AddClassId(LookupClassId(klass));
1175   __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(klass));
1176   __ AddClassId(LookupClassId(klass->GetSuperClass()));
1177   __ AddObjectId(klass->GetClassLoader());
1178   __ AddObjectId(nullptr);    // no signer
1179   __ AddObjectId(nullptr);    // no prot domain
1180   __ AddObjectId(nullptr);    // reserved
1181   __ AddObjectId(nullptr);    // reserved
1182   if (klass->IsClassClass()) {
1183     // ClassObjects have their static fields appended, so aren't all the same size.
1184     // But they're at least this size.
1185     __ AddU4(class_size_without_overhead);  // instance size
1186   } else if (klass->IsStringClass()) {
1187     // Strings are variable length with character data at the end like arrays.
1188     // This outputs the size of an empty string.
1189     __ AddU4(sizeof(mirror::String));
1190   } else if (klass->IsArrayClass() || klass->IsPrimitive()) {
1191     __ AddU4(0);
1192   } else {
1193     __ AddU4(klass->GetObjectSize());  // instance size
1194   }
1195 
1196   __ AddU2(0);  // empty const pool
1197 
1198   // Static fields
1199   if (overhead_size == 0) {
1200     __ AddU2(static_cast<uint16_t>(0));
1201   } else {
1202     __ AddU2(static_cast<uint16_t>(num_static_fields + 1));
1203     __ AddStringId(LookupStringId(kClassOverheadName));
1204     __ AddU1(hprof_basic_object);
1205     __ AddClassStaticsId(klass);
1206 
1207     for (size_t i = 0; i < num_static_fields; ++i) {
1208       ArtField* f = klass->GetStaticField(i);
1209 
1210       size_t size;
1211       HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), &size);
1212       __ AddStringId(LookupStringId(f->GetName()));
1213       __ AddU1(t);
1214       switch (t) {
1215         case hprof_basic_byte:
1216           __ AddU1(f->GetByte(klass));
1217           break;
1218         case hprof_basic_boolean:
1219           __ AddU1(f->GetBoolean(klass));
1220           break;
1221         case hprof_basic_char:
1222           __ AddU2(f->GetChar(klass));
1223           break;
1224         case hprof_basic_short:
1225           __ AddU2(f->GetShort(klass));
1226           break;
1227         case hprof_basic_float:
1228         case hprof_basic_int:
1229         case hprof_basic_object:
1230           __ AddU4(f->Get32(klass));
1231           break;
1232         case hprof_basic_double:
1233         case hprof_basic_long:
1234           __ AddU8(f->Get64(klass));
1235           break;
1236         default:
1237           LOG(FATAL) << "Unexpected size " << size;
1238           UNREACHABLE();
1239       }
1240     }
1241   }
1242 
1243   // Instance fields for this class (no superclass fields)
1244   int iFieldCount = klass->NumInstanceFields();
1245   if (klass->IsStringClass()) {
1246     __ AddU2((uint16_t)iFieldCount + 1);
1247   } else {
1248     __ AddU2((uint16_t)iFieldCount);
1249   }
1250   for (int i = 0; i < iFieldCount; ++i) {
1251     ArtField* f = klass->GetInstanceField(i);
1252     __ AddStringId(LookupStringId(f->GetName()));
1253     HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), nullptr);
1254     __ AddU1(t);
1255   }
1256   // Add native value character array for strings.
1257   if (klass->IsStringClass()) {
1258     __ AddStringId(LookupStringId("value"));
1259     __ AddU1(hprof_basic_object);
1260   }
1261 }
1262 
DumpHeapArray(mirror::Array * obj,mirror::Class * klass)1263 void Hprof::DumpHeapArray(mirror::Array* obj, mirror::Class* klass) {
1264   uint32_t length = obj->GetLength();
1265 
1266   if (obj->IsObjectArray()) {
1267     // obj is an object array.
1268     __ AddU1(HPROF_OBJECT_ARRAY_DUMP);
1269 
1270     __ AddObjectId(obj);
1271     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1272     __ AddU4(length);
1273     __ AddClassId(LookupClassId(klass));
1274 
1275     // Dump the elements, which are always objects or null.
1276     __ AddIdList(obj->AsObjectArray<mirror::Object>());
1277   } else {
1278     size_t size;
1279     HprofBasicType t = SignatureToBasicTypeAndSize(
1280         Primitive::Descriptor(klass->GetComponentType()->GetPrimitiveType()), &size);
1281 
1282     // obj is a primitive array.
1283     __ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
1284 
1285     __ AddObjectId(obj);
1286     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1287     __ AddU4(length);
1288     __ AddU1(t);
1289 
1290     // Dump the raw, packed element values.
1291     if (size == 1) {
1292       __ AddU1List(reinterpret_cast<const uint8_t*>(obj->GetRawData(sizeof(uint8_t), 0)), length);
1293     } else if (size == 2) {
1294       __ AddU2List(reinterpret_cast<const uint16_t*>(obj->GetRawData(sizeof(uint16_t), 0)), length);
1295     } else if (size == 4) {
1296       __ AddU4List(reinterpret_cast<const uint32_t*>(obj->GetRawData(sizeof(uint32_t), 0)), length);
1297     } else if (size == 8) {
1298       __ AddU8List(reinterpret_cast<const uint64_t*>(obj->GetRawData(sizeof(uint64_t), 0)), length);
1299     }
1300   }
1301 }
1302 
DumpHeapInstanceObject(mirror::Object * obj,mirror::Class * klass)1303 void Hprof::DumpHeapInstanceObject(mirror::Object* obj, mirror::Class* klass) {
1304   // obj is an instance object.
1305   __ AddU1(HPROF_INSTANCE_DUMP);
1306   __ AddObjectId(obj);
1307   __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1308   __ AddClassId(LookupClassId(klass));
1309 
1310   // Reserve some space for the length of the instance data, which we won't
1311   // know until we're done writing it.
1312   size_t size_patch_offset = output_->Length();
1313   __ AddU4(0x77777777);
1314 
1315   // What we will use for the string value if the object is a string.
1316   mirror::Object* string_value = nullptr;
1317 
1318   // Write the instance data;  fields for this class, followed by super class fields, and so on.
1319   do {
1320     const size_t instance_fields = klass->NumInstanceFields();
1321     for (size_t i = 0; i < instance_fields; ++i) {
1322       ArtField* f = klass->GetInstanceField(i);
1323       size_t size;
1324       HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), &size);
1325       switch (t) {
1326       case hprof_basic_byte:
1327         __ AddU1(f->GetByte(obj));
1328         break;
1329       case hprof_basic_boolean:
1330         __ AddU1(f->GetBoolean(obj));
1331         break;
1332       case hprof_basic_char:
1333         __ AddU2(f->GetChar(obj));
1334         break;
1335       case hprof_basic_short:
1336         __ AddU2(f->GetShort(obj));
1337         break;
1338       case hprof_basic_float:
1339       case hprof_basic_int:
1340       case hprof_basic_object:
1341         __ AddU4(f->Get32(obj));
1342         break;
1343       case hprof_basic_double:
1344       case hprof_basic_long:
1345         __ AddU8(f->Get64(obj));
1346         break;
1347       }
1348     }
1349     // Add value field for String if necessary.
1350     if (klass->IsStringClass()) {
1351       mirror::String* s = obj->AsString();
1352       if (s->GetLength() == 0) {
1353         // If string is empty, use an object-aligned address within the string for the value.
1354         string_value = reinterpret_cast<mirror::Object*>(
1355             reinterpret_cast<uintptr_t>(s) + kObjectAlignment);
1356       } else {
1357         string_value = reinterpret_cast<mirror::Object*>(s->GetValue());
1358       }
1359       __ AddObjectId(string_value);
1360     }
1361 
1362     klass = klass->GetSuperClass();
1363   } while (klass != nullptr);
1364 
1365   // Patch the instance field length.
1366   __ UpdateU4(size_patch_offset, output_->Length() - (size_patch_offset + 4));
1367 
1368   // Output native value character array for strings.
1369   CHECK_EQ(obj->IsString(), string_value != nullptr);
1370   if (string_value != nullptr) {
1371     mirror::String* s = obj->AsString();
1372     __ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
1373     __ AddObjectId(string_value);
1374     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1375     __ AddU4(s->GetLength());
1376     __ AddU1(hprof_basic_char);
1377     __ AddU2List(s->GetValue(), s->GetLength());
1378   }
1379 }
1380 
VisitRoot(mirror::Object * obj,const RootInfo & info)1381 void Hprof::VisitRoot(mirror::Object* obj, const RootInfo& info) {
1382   static const HprofHeapTag xlate[] = {
1383     HPROF_ROOT_UNKNOWN,
1384     HPROF_ROOT_JNI_GLOBAL,
1385     HPROF_ROOT_JNI_LOCAL,
1386     HPROF_ROOT_JAVA_FRAME,
1387     HPROF_ROOT_NATIVE_STACK,
1388     HPROF_ROOT_STICKY_CLASS,
1389     HPROF_ROOT_THREAD_BLOCK,
1390     HPROF_ROOT_MONITOR_USED,
1391     HPROF_ROOT_THREAD_OBJECT,
1392     HPROF_ROOT_INTERNED_STRING,
1393     HPROF_ROOT_FINALIZING,
1394     HPROF_ROOT_DEBUGGER,
1395     HPROF_ROOT_REFERENCE_CLEANUP,
1396     HPROF_ROOT_VM_INTERNAL,
1397     HPROF_ROOT_JNI_MONITOR,
1398   };
1399   CHECK_LT(info.GetType(), sizeof(xlate) / sizeof(HprofHeapTag));
1400   if (obj == nullptr) {
1401     return;
1402   }
1403   MarkRootObject(obj, 0, xlate[info.GetType()], info.GetThreadId());
1404 }
1405 
1406 // If "direct_to_ddms" is true, the other arguments are ignored, and data is
1407 // sent directly to DDMS.
1408 // If "fd" is >= 0, the output will be written to that file descriptor.
1409 // Otherwise, "filename" is used to create an output file.
DumpHeap(const char * filename,int fd,bool direct_to_ddms)1410 void DumpHeap(const char* filename, int fd, bool direct_to_ddms) {
1411   CHECK(filename != nullptr);
1412 
1413   Thread* self = Thread::Current();
1414   gc::Heap* heap = Runtime::Current()->GetHeap();
1415   if (heap->IsGcConcurrentAndMoving()) {
1416     // Need to take a heap dump while GC isn't running. See the
1417     // comment in Heap::VisitObjects().
1418     heap->IncrementDisableMovingGC(self);
1419   }
1420   {
1421     ScopedSuspendAll ssa(__FUNCTION__, true /* long suspend */);
1422     Hprof hprof(filename, fd, direct_to_ddms);
1423     hprof.Dump();
1424   }
1425   if (heap->IsGcConcurrentAndMoving()) {
1426     heap->DecrementDisableMovingGC(self);
1427   }
1428 }
1429 
1430 }  // namespace hprof
1431 }  // namespace art
1432