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 "android-base/stringprintf.h"
41 
42 #include "art_field-inl.h"
43 #include "art_method-inl.h"
44 #include "base/logging.h"
45 #include "base/time_utils.h"
46 #include "base/unix_file/fd_file.h"
47 #include "class_linker.h"
48 #include "common_throws.h"
49 #include "debugger.h"
50 #include "dex_file-inl.h"
51 #include "gc_root.h"
52 #include "gc/accounting/heap_bitmap.h"
53 #include "gc/allocation_record.h"
54 #include "gc/scoped_gc_critical_section.h"
55 #include "gc/heap.h"
56 #include "gc/space/space.h"
57 #include "globals.h"
58 #include "jdwp/jdwp.h"
59 #include "jdwp/jdwp_priv.h"
60 #include "mirror/class.h"
61 #include "mirror/class-inl.h"
62 #include "mirror/object-refvisitor-inl.h"
63 #include "os.h"
64 #include "safe_map.h"
65 #include "scoped_thread_state_change-inl.h"
66 #include "thread_list.h"
67 
68 namespace art {
69 
70 namespace hprof {
71 
72 static constexpr bool kDirectStream = true;
73 
74 static constexpr uint32_t kHprofTime = 0;
75 static constexpr uint32_t kHprofNullThread = 0;
76 
77 static constexpr size_t kMaxObjectsPerSegment = 128;
78 static constexpr size_t kMaxBytesPerSegment = 4096;
79 
80 // The static field-name for the synthetic object generated to account for class static overhead.
81 static constexpr const char* kClassOverheadName = "$classOverhead";
82 
83 enum HprofTag {
84   HPROF_TAG_STRING = 0x01,
85   HPROF_TAG_LOAD_CLASS = 0x02,
86   HPROF_TAG_UNLOAD_CLASS = 0x03,
87   HPROF_TAG_STACK_FRAME = 0x04,
88   HPROF_TAG_STACK_TRACE = 0x05,
89   HPROF_TAG_ALLOC_SITES = 0x06,
90   HPROF_TAG_HEAP_SUMMARY = 0x07,
91   HPROF_TAG_START_THREAD = 0x0A,
92   HPROF_TAG_END_THREAD = 0x0B,
93   HPROF_TAG_HEAP_DUMP = 0x0C,
94   HPROF_TAG_HEAP_DUMP_SEGMENT = 0x1C,
95   HPROF_TAG_HEAP_DUMP_END = 0x2C,
96   HPROF_TAG_CPU_SAMPLES = 0x0D,
97   HPROF_TAG_CONTROL_SETTINGS = 0x0E,
98 };
99 
100 // Values for the first byte of HEAP_DUMP and HEAP_DUMP_SEGMENT records:
101 enum HprofHeapTag {
102   // Traditional.
103   HPROF_ROOT_UNKNOWN = 0xFF,
104   HPROF_ROOT_JNI_GLOBAL = 0x01,
105   HPROF_ROOT_JNI_LOCAL = 0x02,
106   HPROF_ROOT_JAVA_FRAME = 0x03,
107   HPROF_ROOT_NATIVE_STACK = 0x04,
108   HPROF_ROOT_STICKY_CLASS = 0x05,
109   HPROF_ROOT_THREAD_BLOCK = 0x06,
110   HPROF_ROOT_MONITOR_USED = 0x07,
111   HPROF_ROOT_THREAD_OBJECT = 0x08,
112   HPROF_CLASS_DUMP = 0x20,
113   HPROF_INSTANCE_DUMP = 0x21,
114   HPROF_OBJECT_ARRAY_DUMP = 0x22,
115   HPROF_PRIMITIVE_ARRAY_DUMP = 0x23,
116 
117   // Android.
118   HPROF_HEAP_DUMP_INFO = 0xfe,
119   HPROF_ROOT_INTERNED_STRING = 0x89,
120   HPROF_ROOT_FINALIZING = 0x8a,  // Obsolete.
121   HPROF_ROOT_DEBUGGER = 0x8b,
122   HPROF_ROOT_REFERENCE_CLEANUP = 0x8c,  // Obsolete.
123   HPROF_ROOT_VM_INTERNAL = 0x8d,
124   HPROF_ROOT_JNI_MONITOR = 0x8e,
125   HPROF_UNREACHABLE = 0x90,  // Obsolete.
126   HPROF_PRIMITIVE_ARRAY_NODATA_DUMP = 0xc3,  // Obsolete.
127 };
128 
129 enum HprofHeapId {
130   HPROF_HEAP_DEFAULT = 0,
131   HPROF_HEAP_ZYGOTE = 'Z',
132   HPROF_HEAP_APP = 'A',
133   HPROF_HEAP_IMAGE = 'I',
134 };
135 
136 enum HprofBasicType {
137   hprof_basic_object = 2,
138   hprof_basic_boolean = 4,
139   hprof_basic_char = 5,
140   hprof_basic_float = 6,
141   hprof_basic_double = 7,
142   hprof_basic_byte = 8,
143   hprof_basic_short = 9,
144   hprof_basic_int = 10,
145   hprof_basic_long = 11,
146 };
147 
148 typedef uint32_t HprofStringId;
149 typedef uint32_t HprofClassObjectId;
150 typedef uint32_t HprofClassSerialNumber;
151 typedef uint32_t HprofStackTraceSerialNumber;
152 typedef uint32_t HprofStackFrameId;
153 static constexpr HprofStackTraceSerialNumber kHprofNullStackTrace = 0;
154 
155 class EndianOutput {
156  public:
EndianOutput()157   EndianOutput() : length_(0), sum_length_(0), max_length_(0), started_(false) {}
~EndianOutput()158   virtual ~EndianOutput() {}
159 
StartNewRecord(uint8_t tag,uint32_t time)160   void StartNewRecord(uint8_t tag, uint32_t time) {
161     if (length_ > 0) {
162       EndRecord();
163     }
164     DCHECK_EQ(length_, 0U);
165     AddU1(tag);
166     AddU4(time);
167     AddU4(0xdeaddead);  // Length, replaced on flush.
168     started_ = true;
169   }
170 
EndRecord()171   void EndRecord() {
172     // Replace length in header.
173     if (started_) {
174       UpdateU4(sizeof(uint8_t) + sizeof(uint32_t),
175                length_ - sizeof(uint8_t) - 2 * sizeof(uint32_t));
176     }
177 
178     HandleEndRecord();
179 
180     sum_length_ += length_;
181     max_length_ = std::max(max_length_, length_);
182     length_ = 0;
183     started_ = false;
184   }
185 
AddU1(uint8_t value)186   void AddU1(uint8_t value) {
187     AddU1List(&value, 1);
188   }
AddU2(uint16_t value)189   void AddU2(uint16_t value) {
190     AddU2List(&value, 1);
191   }
AddU4(uint32_t value)192   void AddU4(uint32_t value) {
193     AddU4List(&value, 1);
194   }
195 
AddU8(uint64_t value)196   void AddU8(uint64_t value) {
197     AddU8List(&value, 1);
198   }
199 
AddObjectId(const mirror::Object * value)200   void AddObjectId(const mirror::Object* value) {
201     AddU4(PointerToLowMemUInt32(value));
202   }
203 
AddStackTraceSerialNumber(HprofStackTraceSerialNumber value)204   void AddStackTraceSerialNumber(HprofStackTraceSerialNumber value) {
205     AddU4(value);
206   }
207 
208   // The ID for the synthetic object generated to account for class static overhead.
AddClassStaticsId(const mirror::Class * value)209   void AddClassStaticsId(const mirror::Class* value) {
210     AddU4(1 | PointerToLowMemUInt32(value));
211   }
212 
AddJniGlobalRefId(jobject value)213   void AddJniGlobalRefId(jobject value) {
214     AddU4(PointerToLowMemUInt32(value));
215   }
216 
AddClassId(HprofClassObjectId value)217   void AddClassId(HprofClassObjectId value) {
218     AddU4(value);
219   }
220 
AddStringId(HprofStringId value)221   void AddStringId(HprofStringId value) {
222     AddU4(value);
223   }
224 
AddU1List(const uint8_t * values,size_t count)225   void AddU1List(const uint8_t* values, size_t count) {
226     HandleU1List(values, count);
227     length_ += count;
228   }
AddU2List(const uint16_t * values,size_t count)229   void AddU2List(const uint16_t* values, size_t count) {
230     HandleU2List(values, count);
231     length_ += count * sizeof(uint16_t);
232   }
AddU4List(const uint32_t * values,size_t count)233   void AddU4List(const uint32_t* values, size_t count) {
234     HandleU4List(values, count);
235     length_ += count * sizeof(uint32_t);
236   }
UpdateU4(size_t offset,uint32_t new_value ATTRIBUTE_UNUSED)237   virtual void UpdateU4(size_t offset, uint32_t new_value ATTRIBUTE_UNUSED) {
238     DCHECK_LE(offset, length_ - 4);
239   }
AddU8List(const uint64_t * values,size_t count)240   void AddU8List(const uint64_t* values, size_t count) {
241     HandleU8List(values, count);
242     length_ += count * sizeof(uint64_t);
243   }
244 
AddIdList(mirror::ObjectArray<mirror::Object> * values)245   void AddIdList(mirror::ObjectArray<mirror::Object>* values)
246       REQUIRES_SHARED(Locks::mutator_lock_) {
247     const int32_t length = values->GetLength();
248     for (int32_t i = 0; i < length; ++i) {
249       AddObjectId(values->GetWithoutChecks(i));
250     }
251   }
252 
AddUtf8String(const char * str)253   void AddUtf8String(const char* str) {
254     // The terminating NUL character is NOT written.
255     AddU1List((const uint8_t*)str, strlen(str));
256   }
257 
Length() const258   size_t Length() const {
259     return length_;
260   }
261 
SumLength() const262   size_t SumLength() const {
263     return sum_length_;
264   }
265 
MaxLength() const266   size_t MaxLength() const {
267     return max_length_;
268   }
269 
270  protected:
HandleU1List(const uint8_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)271   virtual void HandleU1List(const uint8_t* values ATTRIBUTE_UNUSED,
272                             size_t count ATTRIBUTE_UNUSED) {
273   }
HandleU1AsU2List(const uint8_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)274   virtual void HandleU1AsU2List(const uint8_t* values ATTRIBUTE_UNUSED,
275                                 size_t count ATTRIBUTE_UNUSED) {
276   }
HandleU2List(const uint16_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)277   virtual void HandleU2List(const uint16_t* values ATTRIBUTE_UNUSED,
278                             size_t count ATTRIBUTE_UNUSED) {
279   }
HandleU4List(const uint32_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)280   virtual void HandleU4List(const uint32_t* values ATTRIBUTE_UNUSED,
281                             size_t count ATTRIBUTE_UNUSED) {
282   }
HandleU8List(const uint64_t * values ATTRIBUTE_UNUSED,size_t count ATTRIBUTE_UNUSED)283   virtual void HandleU8List(const uint64_t* values ATTRIBUTE_UNUSED,
284                             size_t count ATTRIBUTE_UNUSED) {
285   }
HandleEndRecord()286   virtual void HandleEndRecord() {
287   }
288 
289   size_t length_;      // Current record size.
290   size_t sum_length_;  // Size of all data.
291   size_t max_length_;  // Maximum seen length.
292   bool started_;       // Was StartRecord called?
293 };
294 
295 // This keeps things buffered until flushed.
296 class EndianOutputBuffered : public EndianOutput {
297  public:
EndianOutputBuffered(size_t reserve_size)298   explicit EndianOutputBuffered(size_t reserve_size) {
299     buffer_.reserve(reserve_size);
300   }
~EndianOutputBuffered()301   virtual ~EndianOutputBuffered() {}
302 
UpdateU4(size_t offset,uint32_t new_value)303   void UpdateU4(size_t offset, uint32_t new_value) OVERRIDE {
304     DCHECK_LE(offset, length_ - 4);
305     buffer_[offset + 0] = static_cast<uint8_t>((new_value >> 24) & 0xFF);
306     buffer_[offset + 1] = static_cast<uint8_t>((new_value >> 16) & 0xFF);
307     buffer_[offset + 2] = static_cast<uint8_t>((new_value >> 8)  & 0xFF);
308     buffer_[offset + 3] = static_cast<uint8_t>((new_value >> 0)  & 0xFF);
309   }
310 
311  protected:
HandleU1List(const uint8_t * values,size_t count)312   void HandleU1List(const uint8_t* values, size_t count) OVERRIDE {
313     DCHECK_EQ(length_, buffer_.size());
314     buffer_.insert(buffer_.end(), values, values + count);
315   }
316 
HandleU1AsU2List(const uint8_t * values,size_t count)317   void HandleU1AsU2List(const uint8_t* values, size_t count) OVERRIDE {
318     DCHECK_EQ(length_, buffer_.size());
319     // All 8-bits are grouped in 2 to make 16-bit block like Java Char
320     if (count & 1) {
321       buffer_.push_back(0);
322     }
323     for (size_t i = 0; i < count; ++i) {
324       uint8_t value = *values;
325       buffer_.push_back(value);
326       values++;
327     }
328   }
329 
HandleU2List(const uint16_t * values,size_t count)330   void HandleU2List(const uint16_t* values, size_t count) OVERRIDE {
331     DCHECK_EQ(length_, buffer_.size());
332     for (size_t i = 0; i < count; ++i) {
333       uint16_t value = *values;
334       buffer_.push_back(static_cast<uint8_t>((value >> 8) & 0xFF));
335       buffer_.push_back(static_cast<uint8_t>((value >> 0) & 0xFF));
336       values++;
337     }
338   }
339 
HandleU4List(const uint32_t * values,size_t count)340   void HandleU4List(const uint32_t* values, size_t count) OVERRIDE {
341     DCHECK_EQ(length_, buffer_.size());
342     for (size_t i = 0; i < count; ++i) {
343       uint32_t value = *values;
344       buffer_.push_back(static_cast<uint8_t>((value >> 24) & 0xFF));
345       buffer_.push_back(static_cast<uint8_t>((value >> 16) & 0xFF));
346       buffer_.push_back(static_cast<uint8_t>((value >> 8)  & 0xFF));
347       buffer_.push_back(static_cast<uint8_t>((value >> 0)  & 0xFF));
348       values++;
349     }
350   }
351 
HandleU8List(const uint64_t * values,size_t count)352   void HandleU8List(const uint64_t* values, size_t count) OVERRIDE {
353     DCHECK_EQ(length_, buffer_.size());
354     for (size_t i = 0; i < count; ++i) {
355       uint64_t value = *values;
356       buffer_.push_back(static_cast<uint8_t>((value >> 56) & 0xFF));
357       buffer_.push_back(static_cast<uint8_t>((value >> 48) & 0xFF));
358       buffer_.push_back(static_cast<uint8_t>((value >> 40) & 0xFF));
359       buffer_.push_back(static_cast<uint8_t>((value >> 32) & 0xFF));
360       buffer_.push_back(static_cast<uint8_t>((value >> 24) & 0xFF));
361       buffer_.push_back(static_cast<uint8_t>((value >> 16) & 0xFF));
362       buffer_.push_back(static_cast<uint8_t>((value >> 8)  & 0xFF));
363       buffer_.push_back(static_cast<uint8_t>((value >> 0)  & 0xFF));
364       values++;
365     }
366   }
367 
HandleEndRecord()368   void HandleEndRecord() OVERRIDE {
369     DCHECK_EQ(buffer_.size(), length_);
370     if (kIsDebugBuild && started_) {
371       uint32_t stored_length =
372           static_cast<uint32_t>(buffer_[5]) << 24 |
373           static_cast<uint32_t>(buffer_[6]) << 16 |
374           static_cast<uint32_t>(buffer_[7]) << 8 |
375           static_cast<uint32_t>(buffer_[8]);
376       DCHECK_EQ(stored_length, length_ - sizeof(uint8_t) - 2 * sizeof(uint32_t));
377     }
378     HandleFlush(buffer_.data(), length_);
379     buffer_.clear();
380   }
381 
HandleFlush(const uint8_t * buffer ATTRIBUTE_UNUSED,size_t length ATTRIBUTE_UNUSED)382   virtual void HandleFlush(const uint8_t* buffer ATTRIBUTE_UNUSED, size_t length ATTRIBUTE_UNUSED) {
383   }
384 
385   std::vector<uint8_t> buffer_;
386 };
387 
388 class FileEndianOutput FINAL : public EndianOutputBuffered {
389  public:
FileEndianOutput(File * fp,size_t reserved_size)390   FileEndianOutput(File* fp, size_t reserved_size)
391       : EndianOutputBuffered(reserved_size), fp_(fp), errors_(false) {
392     DCHECK(fp != nullptr);
393   }
~FileEndianOutput()394   ~FileEndianOutput() {
395   }
396 
Errors()397   bool Errors() {
398     return errors_;
399   }
400 
401  protected:
HandleFlush(const uint8_t * buffer,size_t length)402   void HandleFlush(const uint8_t* buffer, size_t length) OVERRIDE {
403     if (!errors_) {
404       errors_ = !fp_->WriteFully(buffer, length);
405     }
406   }
407 
408  private:
409   File* fp_;
410   bool errors_;
411 };
412 
413 class NetStateEndianOutput FINAL : public EndianOutputBuffered {
414  public:
NetStateEndianOutput(JDWP::JdwpNetStateBase * net_state,size_t reserved_size)415   NetStateEndianOutput(JDWP::JdwpNetStateBase* net_state, size_t reserved_size)
416       : EndianOutputBuffered(reserved_size), net_state_(net_state) {
417     DCHECK(net_state != nullptr);
418   }
~NetStateEndianOutput()419   ~NetStateEndianOutput() {}
420 
421  protected:
HandleFlush(const uint8_t * buffer,size_t length)422   void HandleFlush(const uint8_t* buffer, size_t length) OVERRIDE {
423     std::vector<iovec> iov;
424     iov.push_back(iovec());
425     iov[0].iov_base = const_cast<void*>(reinterpret_cast<const void*>(buffer));
426     iov[0].iov_len = length;
427     net_state_->WriteBufferedPacketLocked(iov);
428   }
429 
430  private:
431   JDWP::JdwpNetStateBase* net_state_;
432 };
433 
434 #define __ output_->
435 
436 class Hprof : public SingleRootVisitor {
437  public:
Hprof(const char * output_filename,int fd,bool direct_to_ddms)438   Hprof(const char* output_filename, int fd, bool direct_to_ddms)
439       : filename_(output_filename),
440         fd_(fd),
441         direct_to_ddms_(direct_to_ddms) {
442     LOG(INFO) << "hprof: heap dump \"" << filename_ << "\" starting...";
443   }
444 
Dump()445   void Dump()
446     REQUIRES(Locks::mutator_lock_)
447     REQUIRES(!Locks::heap_bitmap_lock_, !Locks::alloc_tracker_lock_) {
448     {
449       MutexLock mu(Thread::Current(), *Locks::alloc_tracker_lock_);
450       if (Runtime::Current()->GetHeap()->IsAllocTrackingEnabled()) {
451         PopulateAllocationTrackingTraces();
452       }
453     }
454 
455     // First pass to measure the size of the dump.
456     size_t overall_size;
457     size_t max_length;
458     {
459       EndianOutput count_output;
460       output_ = &count_output;
461       ProcessHeap(false);
462       overall_size = count_output.SumLength();
463       max_length = count_output.MaxLength();
464       output_ = nullptr;
465     }
466 
467     bool okay;
468     visited_objects_.clear();
469     if (direct_to_ddms_) {
470       if (kDirectStream) {
471         okay = DumpToDdmsDirect(overall_size, max_length, CHUNK_TYPE("HPDS"));
472       } else {
473         okay = DumpToDdmsBuffered(overall_size, max_length);
474       }
475     } else {
476       okay = DumpToFile(overall_size, max_length);
477     }
478 
479     if (okay) {
480       const uint64_t duration = NanoTime() - start_ns_;
481       LOG(INFO) << "hprof: heap dump completed (" << PrettySize(RoundUp(overall_size, KB))
482                 << ") in " << PrettyDuration(duration)
483                 << " objects " << total_objects_
484                 << " objects with stack traces " << total_objects_with_stack_trace_;
485     }
486   }
487 
488  private:
VisitObjectCallback(mirror::Object * obj,void * arg)489   static void VisitObjectCallback(mirror::Object* obj, void* arg)
490       REQUIRES_SHARED(Locks::mutator_lock_) {
491     DCHECK(obj != nullptr);
492     DCHECK(arg != nullptr);
493     reinterpret_cast<Hprof*>(arg)->DumpHeapObject(obj);
494   }
495 
496   void DumpHeapObject(mirror::Object* obj)
497       REQUIRES_SHARED(Locks::mutator_lock_);
498 
499   void DumpHeapClass(mirror::Class* klass)
500       REQUIRES_SHARED(Locks::mutator_lock_);
501 
502   void DumpHeapArray(mirror::Array* obj, mirror::Class* klass)
503       REQUIRES_SHARED(Locks::mutator_lock_);
504 
505   void DumpHeapInstanceObject(mirror::Object* obj, mirror::Class* klass)
506       REQUIRES_SHARED(Locks::mutator_lock_);
507 
ProcessHeap(bool header_first)508   void ProcessHeap(bool header_first)
509       REQUIRES(Locks::mutator_lock_) {
510     // Reset current heap and object count.
511     current_heap_ = HPROF_HEAP_DEFAULT;
512     objects_in_segment_ = 0;
513 
514     if (header_first) {
515       ProcessHeader(true);
516       ProcessBody();
517     } else {
518       ProcessBody();
519       ProcessHeader(false);
520     }
521   }
522 
ProcessBody()523   void ProcessBody() REQUIRES(Locks::mutator_lock_) {
524     Runtime* const runtime = Runtime::Current();
525     // Walk the roots and the heap.
526     output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_SEGMENT, kHprofTime);
527 
528     simple_roots_.clear();
529     runtime->VisitRoots(this);
530     runtime->VisitImageRoots(this);
531     runtime->GetHeap()->VisitObjectsPaused(VisitObjectCallback, this);
532 
533     output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_END, kHprofTime);
534     output_->EndRecord();
535   }
536 
ProcessHeader(bool string_first)537   void ProcessHeader(bool string_first) REQUIRES(Locks::mutator_lock_) {
538     // Write the header.
539     WriteFixedHeader();
540     // Write the string and class tables, and any stack traces, to the header.
541     // (jhat requires that these appear before any of the data in the body that refers to them.)
542     // jhat also requires the string table appear before class table and stack traces.
543     // However, WriteStackTraces() can modify the string table, so it's necessary to call
544     // WriteStringTable() last in the first pass, to compute the correct length of the output.
545     if (string_first) {
546       WriteStringTable();
547     }
548     WriteClassTable();
549     WriteStackTraces();
550     if (!string_first) {
551       WriteStringTable();
552     }
553     output_->EndRecord();
554   }
555 
WriteClassTable()556   void WriteClassTable() REQUIRES_SHARED(Locks::mutator_lock_) {
557     for (const auto& p : classes_) {
558       mirror::Class* c = p.first;
559       HprofClassSerialNumber sn = p.second;
560       CHECK(c != nullptr);
561       output_->StartNewRecord(HPROF_TAG_LOAD_CLASS, kHprofTime);
562       // LOAD CLASS format:
563       // U4: class serial number (always > 0)
564       // ID: class object ID. We use the address of the class object structure as its ID.
565       // U4: stack trace serial number
566       // ID: class name string ID
567       __ AddU4(sn);
568       __ AddObjectId(c);
569       __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(c));
570       __ AddStringId(LookupClassNameId(c));
571     }
572   }
573 
WriteStringTable()574   void WriteStringTable() {
575     for (const auto& p : strings_) {
576       const std::string& string = p.first;
577       const HprofStringId id = p.second;
578 
579       output_->StartNewRecord(HPROF_TAG_STRING, kHprofTime);
580 
581       // STRING format:
582       // ID:  ID for this string
583       // U1*: UTF8 characters for string (NOT null terminated)
584       //      (the record format encodes the length)
585       __ AddU4(id);
586       __ AddUtf8String(string.c_str());
587     }
588   }
589 
StartNewHeapDumpSegment()590   void StartNewHeapDumpSegment() {
591     // This flushes the old segment and starts a new one.
592     output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_SEGMENT, kHprofTime);
593     objects_in_segment_ = 0;
594     // Starting a new HEAP_DUMP resets the heap to default.
595     current_heap_ = HPROF_HEAP_DEFAULT;
596   }
597 
CheckHeapSegmentConstraints()598   void CheckHeapSegmentConstraints() {
599     if (objects_in_segment_ >= kMaxObjectsPerSegment || output_->Length() >= kMaxBytesPerSegment) {
600       StartNewHeapDumpSegment();
601     }
602   }
603 
604   void VisitRoot(mirror::Object* obj, const RootInfo& root_info)
605       OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_);
606   void MarkRootObject(const mirror::Object* obj, jobject jni_obj, HprofHeapTag heap_tag,
607                       uint32_t thread_serial);
608 
LookupClassId(mirror::Class * c)609   HprofClassObjectId LookupClassId(mirror::Class* c) REQUIRES_SHARED(Locks::mutator_lock_) {
610     if (c != nullptr) {
611       auto it = classes_.find(c);
612       if (it == classes_.end()) {
613         // first time to see this class
614         HprofClassSerialNumber sn = next_class_serial_number_++;
615         classes_.Put(c, sn);
616         // Make sure that we've assigned a string ID for this class' name
617         LookupClassNameId(c);
618       }
619     }
620     return PointerToLowMemUInt32(c);
621   }
622 
LookupStackTraceSerialNumber(const mirror::Object * obj)623   HprofStackTraceSerialNumber LookupStackTraceSerialNumber(const mirror::Object* obj)
624       REQUIRES_SHARED(Locks::mutator_lock_) {
625     auto r = allocation_records_.find(obj);
626     if (r == allocation_records_.end()) {
627       return kHprofNullStackTrace;
628     } else {
629       const gc::AllocRecordStackTrace* trace = r->second;
630       auto result = traces_.find(trace);
631       CHECK(result != traces_.end());
632       return result->second;
633     }
634   }
635 
LookupStringId(mirror::String * string)636   HprofStringId LookupStringId(mirror::String* string) REQUIRES_SHARED(Locks::mutator_lock_) {
637     return LookupStringId(string->ToModifiedUtf8());
638   }
639 
LookupStringId(const char * string)640   HprofStringId LookupStringId(const char* string) {
641     return LookupStringId(std::string(string));
642   }
643 
LookupStringId(const std::string & string)644   HprofStringId LookupStringId(const std::string& string) {
645     auto it = strings_.find(string);
646     if (it != strings_.end()) {
647       return it->second;
648     }
649     HprofStringId id = next_string_id_++;
650     strings_.Put(string, id);
651     return id;
652   }
653 
LookupClassNameId(mirror::Class * c)654   HprofStringId LookupClassNameId(mirror::Class* c) REQUIRES_SHARED(Locks::mutator_lock_) {
655     return LookupStringId(c->PrettyDescriptor());
656   }
657 
WriteFixedHeader()658   void WriteFixedHeader() {
659     // Write the file header.
660     // U1: NUL-terminated magic string.
661     const char magic[] = "JAVA PROFILE 1.0.3";
662     __ AddU1List(reinterpret_cast<const uint8_t*>(magic), sizeof(magic));
663 
664     // U4: size of identifiers.  We're using addresses as IDs and our heap references are stored
665     // as uint32_t.
666     // Note of warning: hprof-conv hard-codes the size of identifiers to 4.
667     static_assert(sizeof(mirror::HeapReference<mirror::Object>) == sizeof(uint32_t),
668                   "Unexpected HeapReference size");
669     __ AddU4(sizeof(uint32_t));
670 
671     // The current time, in milliseconds since 0:00 GMT, 1/1/70.
672     timeval now;
673     const uint64_t nowMs = (gettimeofday(&now, nullptr) < 0) ? 0 :
674         (uint64_t)now.tv_sec * 1000 + now.tv_usec / 1000;
675     // TODO: It seems it would be correct to use U8.
676     // U4: high word of the 64-bit time.
677     __ AddU4(static_cast<uint32_t>(nowMs >> 32));
678     // U4: low word of the 64-bit time.
679     __ AddU4(static_cast<uint32_t>(nowMs & 0xFFFFFFFF));
680   }
681 
WriteStackTraces()682   void WriteStackTraces() REQUIRES_SHARED(Locks::mutator_lock_) {
683     // Write a dummy stack trace record so the analysis tools don't freak out.
684     output_->StartNewRecord(HPROF_TAG_STACK_TRACE, kHprofTime);
685     __ AddStackTraceSerialNumber(kHprofNullStackTrace);
686     __ AddU4(kHprofNullThread);
687     __ AddU4(0);    // no frames
688 
689     // TODO: jhat complains "WARNING: Stack trace not found for serial # -1", but no trace should
690     // have -1 as its serial number (as long as HprofStackTraceSerialNumber doesn't overflow).
691     for (const auto& it : traces_) {
692       const gc::AllocRecordStackTrace* trace = it.first;
693       HprofStackTraceSerialNumber trace_sn = it.second;
694       size_t depth = trace->GetDepth();
695 
696       // First write stack frames of the trace
697       for (size_t i = 0; i < depth; ++i) {
698         const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
699         ArtMethod* method = frame->GetMethod();
700         CHECK(method != nullptr);
701         output_->StartNewRecord(HPROF_TAG_STACK_FRAME, kHprofTime);
702         // STACK FRAME format:
703         // ID: stack frame ID. We use the address of the AllocRecordStackTraceElement object as its ID.
704         // ID: method name string ID
705         // ID: method signature string ID
706         // ID: source file name string ID
707         // U4: class serial number
708         // U4: >0, line number; 0, no line information available; -1, unknown location
709         auto frame_result = frames_.find(frame);
710         CHECK(frame_result != frames_.end());
711         __ AddU4(frame_result->second);
712         __ AddStringId(LookupStringId(method->GetName()));
713         __ AddStringId(LookupStringId(method->GetSignature().ToString()));
714         const char* source_file = method->GetDeclaringClassSourceFile();
715         if (source_file == nullptr) {
716           source_file = "";
717         }
718         __ AddStringId(LookupStringId(source_file));
719         auto class_result = classes_.find(method->GetDeclaringClass());
720         CHECK(class_result != classes_.end());
721         __ AddU4(class_result->second);
722         __ AddU4(frame->ComputeLineNumber());
723       }
724 
725       // Then write the trace itself
726       output_->StartNewRecord(HPROF_TAG_STACK_TRACE, kHprofTime);
727       // STACK TRACE format:
728       // U4: stack trace serial number. We use the address of the AllocRecordStackTrace object as its serial number.
729       // U4: thread serial number. We use Thread::GetTid().
730       // U4: number of frames
731       // [ID]*: series of stack frame ID's
732       __ AddStackTraceSerialNumber(trace_sn);
733       __ AddU4(trace->GetTid());
734       __ AddU4(depth);
735       for (size_t i = 0; i < depth; ++i) {
736         const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
737         auto frame_result = frames_.find(frame);
738         CHECK(frame_result != frames_.end());
739         __ AddU4(frame_result->second);
740       }
741     }
742   }
743 
DumpToDdmsBuffered(size_t overall_size ATTRIBUTE_UNUSED,size_t max_length ATTRIBUTE_UNUSED)744   bool DumpToDdmsBuffered(size_t overall_size ATTRIBUTE_UNUSED, size_t max_length ATTRIBUTE_UNUSED)
745       REQUIRES(Locks::mutator_lock_) {
746     LOG(FATAL) << "Unimplemented";
747     UNREACHABLE();
748     //        // Send the data off to DDMS.
749     //        iovec iov[2];
750     //        iov[0].iov_base = header_data_ptr_;
751     //        iov[0].iov_len = header_data_size_;
752     //        iov[1].iov_base = body_data_ptr_;
753     //        iov[1].iov_len = body_data_size_;
754     //        Dbg::DdmSendChunkV(CHUNK_TYPE("HPDS"), iov, 2);
755   }
756 
DumpToFile(size_t overall_size,size_t max_length)757   bool DumpToFile(size_t overall_size, size_t max_length)
758       REQUIRES(Locks::mutator_lock_) {
759     // Where exactly are we writing to?
760     int out_fd;
761     if (fd_ >= 0) {
762       out_fd = dup(fd_);
763       if (out_fd < 0) {
764         ThrowRuntimeException("Couldn't dump heap; dup(%d) failed: %s", fd_, strerror(errno));
765         return false;
766       }
767     } else {
768       out_fd = open(filename_.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0644);
769       if (out_fd < 0) {
770         ThrowRuntimeException("Couldn't dump heap; open(\"%s\") failed: %s", filename_.c_str(),
771                               strerror(errno));
772         return false;
773       }
774     }
775 
776     std::unique_ptr<File> file(new File(out_fd, filename_, true));
777     bool okay;
778     {
779       FileEndianOutput file_output(file.get(), max_length);
780       output_ = &file_output;
781       ProcessHeap(true);
782       okay = !file_output.Errors();
783 
784       if (okay) {
785         // Check for expected size. Output is expected to be less-or-equal than first phase, see
786         // b/23521263.
787         DCHECK_LE(file_output.SumLength(), overall_size);
788       }
789       output_ = nullptr;
790     }
791 
792     if (okay) {
793       okay = file->FlushCloseOrErase() == 0;
794     } else {
795       file->Erase();
796     }
797     if (!okay) {
798       std::string msg(android::base::StringPrintf("Couldn't dump heap; writing \"%s\" failed: %s",
799                                                   filename_.c_str(),
800                                                   strerror(errno)));
801       ThrowRuntimeException("%s", msg.c_str());
802       LOG(ERROR) << msg;
803     }
804 
805     return okay;
806   }
807 
DumpToDdmsDirect(size_t overall_size,size_t max_length,uint32_t chunk_type)808   bool DumpToDdmsDirect(size_t overall_size, size_t max_length, uint32_t chunk_type)
809       REQUIRES(Locks::mutator_lock_) {
810     CHECK(direct_to_ddms_);
811     JDWP::JdwpState* state = Dbg::GetJdwpState();
812     CHECK(state != nullptr);
813     JDWP::JdwpNetStateBase* net_state = state->netState;
814     CHECK(net_state != nullptr);
815 
816     // Hold the socket lock for the whole time since we want this to be atomic.
817     MutexLock mu(Thread::Current(), *net_state->GetSocketLock());
818 
819     // Prepare the Ddms chunk.
820     constexpr size_t kChunkHeaderSize = kJDWPHeaderLen + 8;
821     uint8_t chunk_header[kChunkHeaderSize] = { 0 };
822     state->SetupChunkHeader(chunk_type, overall_size, kChunkHeaderSize, chunk_header);
823 
824     // Prepare the output and send the chunk header.
825     NetStateEndianOutput net_output(net_state, max_length);
826     output_ = &net_output;
827     net_output.AddU1List(chunk_header, kChunkHeaderSize);
828 
829     // Write the dump.
830     ProcessHeap(true);
831 
832     // Check for expected size. See DumpToFile for comment.
833     DCHECK_LE(net_output.SumLength(), overall_size + kChunkHeaderSize);
834     output_ = nullptr;
835 
836     return true;
837   }
838 
PopulateAllocationTrackingTraces()839   void PopulateAllocationTrackingTraces()
840       REQUIRES(Locks::mutator_lock_, Locks::alloc_tracker_lock_) {
841     gc::AllocRecordObjectMap* records = Runtime::Current()->GetHeap()->GetAllocationRecords();
842     CHECK(records != nullptr);
843     HprofStackTraceSerialNumber next_trace_sn = kHprofNullStackTrace + 1;
844     HprofStackFrameId next_frame_id = 0;
845     size_t count = 0;
846 
847     for (auto it = records->Begin(), end = records->End(); it != end; ++it) {
848       const mirror::Object* obj = it->first.Read();
849       if (obj == nullptr) {
850         continue;
851       }
852       ++count;
853       const gc::AllocRecordStackTrace* trace = it->second.GetStackTrace();
854 
855       // Copy the pair into a real hash map to speed up look up.
856       auto records_result = allocation_records_.emplace(obj, trace);
857       // The insertion should always succeed, i.e. no duplicate object pointers in "records"
858       CHECK(records_result.second);
859 
860       // Generate serial numbers for traces, and IDs for frames.
861       auto traces_result = traces_.find(trace);
862       if (traces_result == traces_.end()) {
863         traces_.emplace(trace, next_trace_sn++);
864         // only check frames if the trace is newly discovered
865         for (size_t i = 0, depth = trace->GetDepth(); i < depth; ++i) {
866           const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
867           auto frames_result = frames_.find(frame);
868           if (frames_result == frames_.end()) {
869             frames_.emplace(frame, next_frame_id++);
870           }
871         }
872       }
873     }
874     CHECK_EQ(traces_.size(), next_trace_sn - kHprofNullStackTrace - 1);
875     CHECK_EQ(frames_.size(), next_frame_id);
876     total_objects_with_stack_trace_ = count;
877   }
878 
879   // If direct_to_ddms_ is set, "filename_" and "fd" will be ignored.
880   // Otherwise, "filename_" must be valid, though if "fd" >= 0 it will
881   // only be used for debug messages.
882   std::string filename_;
883   int fd_;
884   bool direct_to_ddms_;
885 
886   uint64_t start_ns_ = NanoTime();
887 
888   EndianOutput* output_ = nullptr;
889 
890   HprofHeapId current_heap_ = HPROF_HEAP_DEFAULT;  // Which heap we're currently dumping.
891   size_t objects_in_segment_ = 0;
892 
893   size_t total_objects_ = 0u;
894   size_t total_objects_with_stack_trace_ = 0u;
895 
896   HprofStringId next_string_id_ = 0x400000;
897   SafeMap<std::string, HprofStringId> strings_;
898   HprofClassSerialNumber next_class_serial_number_ = 1;
899   SafeMap<mirror::Class*, HprofClassSerialNumber> classes_;
900 
901   std::unordered_map<const gc::AllocRecordStackTrace*, HprofStackTraceSerialNumber,
902                      gc::HashAllocRecordTypesPtr<gc::AllocRecordStackTrace>,
903                      gc::EqAllocRecordTypesPtr<gc::AllocRecordStackTrace>> traces_;
904   std::unordered_map<const gc::AllocRecordStackTraceElement*, HprofStackFrameId,
905                      gc::HashAllocRecordTypesPtr<gc::AllocRecordStackTraceElement>,
906                      gc::EqAllocRecordTypesPtr<gc::AllocRecordStackTraceElement>> frames_;
907   std::unordered_map<const mirror::Object*, const gc::AllocRecordStackTrace*> allocation_records_;
908 
909   // Set used to keep track of what simple root records we have already
910   // emitted, to avoid emitting duplicate entries. The simple root records are
911   // those that contain no other information than the root type and the object
912   // id. A pair of root type and object id is packed into a uint64_t, with
913   // the root type in the upper 32 bits and the object id in the lower 32
914   // bits.
915   std::unordered_set<uint64_t> simple_roots_;
916 
917   // To make sure we don't dump the same object multiple times. b/34967844
918   std::unordered_set<mirror::Object*> visited_objects_;
919 
920   friend class GcRootVisitor;
921   DISALLOW_COPY_AND_ASSIGN(Hprof);
922 };
923 
SignatureToBasicTypeAndSize(const char * sig,size_t * size_out)924 static HprofBasicType SignatureToBasicTypeAndSize(const char* sig, size_t* size_out) {
925   char c = sig[0];
926   HprofBasicType ret;
927   size_t size;
928 
929   switch (c) {
930     case '[':
931     case 'L':
932       ret = hprof_basic_object;
933       size = 4;
934       break;
935     case 'Z':
936       ret = hprof_basic_boolean;
937       size = 1;
938       break;
939     case 'C':
940       ret = hprof_basic_char;
941       size = 2;
942       break;
943     case 'F':
944       ret = hprof_basic_float;
945       size = 4;
946       break;
947     case 'D':
948       ret = hprof_basic_double;
949       size = 8;
950       break;
951     case 'B':
952       ret = hprof_basic_byte;
953       size = 1;
954       break;
955     case 'S':
956       ret = hprof_basic_short;
957       size = 2;
958       break;
959     case 'I':
960       ret = hprof_basic_int;
961       size = 4;
962       break;
963     case 'J':
964       ret = hprof_basic_long;
965       size = 8;
966       break;
967     default:
968       LOG(FATAL) << "UNREACHABLE";
969       UNREACHABLE();
970   }
971 
972   if (size_out != nullptr) {
973     *size_out = size;
974   }
975 
976   return ret;
977 }
978 
979 // Always called when marking objects, but only does
980 // something when ctx->gc_scan_state_ is non-zero, which is usually
981 // only true when marking the root set or unreachable
982 // objects.  Used to add rootset references to obj.
MarkRootObject(const mirror::Object * obj,jobject jni_obj,HprofHeapTag heap_tag,uint32_t thread_serial)983 void Hprof::MarkRootObject(const mirror::Object* obj, jobject jni_obj, HprofHeapTag heap_tag,
984                            uint32_t thread_serial) {
985   if (heap_tag == 0) {
986     return;
987   }
988 
989   CheckHeapSegmentConstraints();
990 
991   switch (heap_tag) {
992     // ID: object ID
993     case HPROF_ROOT_UNKNOWN:
994     case HPROF_ROOT_STICKY_CLASS:
995     case HPROF_ROOT_MONITOR_USED:
996     case HPROF_ROOT_INTERNED_STRING:
997     case HPROF_ROOT_DEBUGGER:
998     case HPROF_ROOT_VM_INTERNAL: {
999       uint64_t key = (static_cast<uint64_t>(heap_tag) << 32) | PointerToLowMemUInt32(obj);
1000       if (simple_roots_.insert(key).second) {
1001         __ AddU1(heap_tag);
1002         __ AddObjectId(obj);
1003       }
1004       break;
1005     }
1006 
1007       // ID: object ID
1008       // ID: JNI global ref ID
1009     case HPROF_ROOT_JNI_GLOBAL:
1010       __ AddU1(heap_tag);
1011       __ AddObjectId(obj);
1012       __ AddJniGlobalRefId(jni_obj);
1013       break;
1014 
1015       // ID: object ID
1016       // U4: thread serial number
1017       // U4: frame number in stack trace (-1 for empty)
1018     case HPROF_ROOT_JNI_LOCAL:
1019     case HPROF_ROOT_JNI_MONITOR:
1020     case HPROF_ROOT_JAVA_FRAME:
1021       __ AddU1(heap_tag);
1022       __ AddObjectId(obj);
1023       __ AddU4(thread_serial);
1024       __ AddU4((uint32_t)-1);
1025       break;
1026 
1027       // ID: object ID
1028       // U4: thread serial number
1029     case HPROF_ROOT_NATIVE_STACK:
1030     case HPROF_ROOT_THREAD_BLOCK:
1031       __ AddU1(heap_tag);
1032       __ AddObjectId(obj);
1033       __ AddU4(thread_serial);
1034       break;
1035 
1036       // ID: thread object ID
1037       // U4: thread serial number
1038       // U4: stack trace serial number
1039     case HPROF_ROOT_THREAD_OBJECT:
1040       __ AddU1(heap_tag);
1041       __ AddObjectId(obj);
1042       __ AddU4(thread_serial);
1043       __ AddU4((uint32_t)-1);    // xxx
1044       break;
1045 
1046     case HPROF_CLASS_DUMP:
1047     case HPROF_INSTANCE_DUMP:
1048     case HPROF_OBJECT_ARRAY_DUMP:
1049     case HPROF_PRIMITIVE_ARRAY_DUMP:
1050     case HPROF_HEAP_DUMP_INFO:
1051     case HPROF_PRIMITIVE_ARRAY_NODATA_DUMP:
1052       // Ignored.
1053       break;
1054 
1055     case HPROF_ROOT_FINALIZING:
1056     case HPROF_ROOT_REFERENCE_CLEANUP:
1057     case HPROF_UNREACHABLE:
1058       LOG(FATAL) << "obsolete tag " << static_cast<int>(heap_tag);
1059       break;
1060   }
1061 
1062   ++objects_in_segment_;
1063 }
1064 
1065 // Use for visiting the GcRoots held live by ArtFields, ArtMethods, and ClassLoaders.
1066 class GcRootVisitor {
1067  public:
GcRootVisitor(Hprof * hprof)1068   explicit GcRootVisitor(Hprof* hprof) : hprof_(hprof) {}
1069 
operator ()(mirror::Object * obj ATTRIBUTE_UNUSED,MemberOffset offset ATTRIBUTE_UNUSED,bool is_static ATTRIBUTE_UNUSED) const1070   void operator()(mirror::Object* obj ATTRIBUTE_UNUSED,
1071                   MemberOffset offset ATTRIBUTE_UNUSED,
1072                   bool is_static ATTRIBUTE_UNUSED) const {}
1073 
1074   // Note that these don't have read barriers. Its OK however since the GC is guaranteed to not be
1075   // running during the hprof dumping process.
VisitRootIfNonNull(mirror::CompressedReference<mirror::Object> * root) const1076   void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
1077       REQUIRES_SHARED(Locks::mutator_lock_) {
1078     if (!root->IsNull()) {
1079       VisitRoot(root);
1080     }
1081   }
1082 
VisitRoot(mirror::CompressedReference<mirror::Object> * root) const1083   void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
1084       REQUIRES_SHARED(Locks::mutator_lock_) {
1085     mirror::Object* obj = root->AsMirrorPtr();
1086     // The two cases are either classes or dex cache arrays. If it is a dex cache array, then use
1087     // VM internal. Otherwise the object is a declaring class of an ArtField or ArtMethod or a
1088     // class from a ClassLoader.
1089     hprof_->VisitRoot(obj, RootInfo(obj->IsClass() ? kRootStickyClass : kRootVMInternal));
1090   }
1091 
1092 
1093  private:
1094   Hprof* const hprof_;
1095 };
1096 
DumpHeapObject(mirror::Object * obj)1097 void Hprof::DumpHeapObject(mirror::Object* obj) {
1098   // Ignore classes that are retired.
1099   if (obj->IsClass() && obj->AsClass()->IsRetired()) {
1100     return;
1101   }
1102   DCHECK(visited_objects_.insert(obj).second) << "Already visited " << obj;
1103 
1104   ++total_objects_;
1105 
1106   GcRootVisitor visitor(this);
1107   obj->VisitReferences(visitor, VoidFunctor());
1108 
1109   gc::Heap* const heap = Runtime::Current()->GetHeap();
1110   const gc::space::ContinuousSpace* const space = heap->FindContinuousSpaceFromObject(obj, true);
1111   HprofHeapId heap_type = HPROF_HEAP_APP;
1112   if (space != nullptr) {
1113     if (space->IsZygoteSpace()) {
1114       heap_type = HPROF_HEAP_ZYGOTE;
1115     } else if (space->IsImageSpace() && heap->ObjectIsInBootImageSpace(obj)) {
1116       // Only count objects in the boot image as HPROF_HEAP_IMAGE, this leaves app image objects as
1117       // HPROF_HEAP_APP. b/35762934
1118       heap_type = HPROF_HEAP_IMAGE;
1119     }
1120   } else {
1121     const auto* los = heap->GetLargeObjectsSpace();
1122     if (los->Contains(obj) && los->IsZygoteLargeObject(Thread::Current(), obj)) {
1123       heap_type = HPROF_HEAP_ZYGOTE;
1124     }
1125   }
1126   CheckHeapSegmentConstraints();
1127 
1128   if (heap_type != current_heap_) {
1129     HprofStringId nameId;
1130 
1131     // This object is in a different heap than the current one.
1132     // Emit a HEAP_DUMP_INFO tag to change heaps.
1133     __ AddU1(HPROF_HEAP_DUMP_INFO);
1134     __ AddU4(static_cast<uint32_t>(heap_type));   // uint32_t: heap type
1135     switch (heap_type) {
1136     case HPROF_HEAP_APP:
1137       nameId = LookupStringId("app");
1138       break;
1139     case HPROF_HEAP_ZYGOTE:
1140       nameId = LookupStringId("zygote");
1141       break;
1142     case HPROF_HEAP_IMAGE:
1143       nameId = LookupStringId("image");
1144       break;
1145     default:
1146       // Internal error
1147       LOG(ERROR) << "Unexpected desiredHeap";
1148       nameId = LookupStringId("<ILLEGAL>");
1149       break;
1150     }
1151     __ AddStringId(nameId);
1152     current_heap_ = heap_type;
1153   }
1154 
1155   mirror::Class* c = obj->GetClass();
1156   if (c == nullptr) {
1157     // This object will bother HprofReader, because it has a null
1158     // class, so just don't dump it. It could be
1159     // gDvm.unlinkedJavaLangClass or it could be an object just
1160     // allocated which hasn't been initialized yet.
1161   } else {
1162     if (obj->IsClass()) {
1163       DumpHeapClass(obj->AsClass());
1164     } else if (c->IsArrayClass()) {
1165       DumpHeapArray(obj->AsArray(), c);
1166     } else {
1167       DumpHeapInstanceObject(obj, c);
1168     }
1169   }
1170 
1171   ++objects_in_segment_;
1172 }
1173 
DumpHeapClass(mirror::Class * klass)1174 void Hprof::DumpHeapClass(mirror::Class* klass) {
1175   if (!klass->IsResolved()) {
1176     // Class is allocated but not yet resolved: we cannot access its fields or super class.
1177     return;
1178   }
1179   const size_t num_static_fields = klass->NumStaticFields();
1180   // Total class size including embedded IMT, embedded vtable, and static fields.
1181   const size_t class_size = klass->GetClassSize();
1182   // Class size excluding static fields (relies on reference fields being the first static fields).
1183   const size_t class_size_without_overhead = sizeof(mirror::Class);
1184   CHECK_LE(class_size_without_overhead, class_size);
1185   const size_t overhead_size = class_size - class_size_without_overhead;
1186 
1187   if (overhead_size != 0) {
1188     // Create a byte array to reflect the allocation of the
1189     // StaticField array at the end of this class.
1190     __ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
1191     __ AddClassStaticsId(klass);
1192     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(klass));
1193     __ AddU4(overhead_size);
1194     __ AddU1(hprof_basic_byte);
1195     for (size_t i = 0; i < overhead_size; ++i) {
1196       __ AddU1(0);
1197     }
1198   }
1199 
1200   __ AddU1(HPROF_CLASS_DUMP);
1201   __ AddClassId(LookupClassId(klass));
1202   __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(klass));
1203   __ AddClassId(LookupClassId(klass->GetSuperClass()));
1204   __ AddObjectId(klass->GetClassLoader());
1205   __ AddObjectId(nullptr);    // no signer
1206   __ AddObjectId(nullptr);    // no prot domain
1207   __ AddObjectId(nullptr);    // reserved
1208   __ AddObjectId(nullptr);    // reserved
1209   if (klass->IsClassClass()) {
1210     // ClassObjects have their static fields appended, so aren't all the same size.
1211     // But they're at least this size.
1212     __ AddU4(class_size_without_overhead);  // instance size
1213   } else if (klass->IsStringClass()) {
1214     // Strings are variable length with character data at the end like arrays.
1215     // This outputs the size of an empty string.
1216     __ AddU4(sizeof(mirror::String));
1217   } else if (klass->IsArrayClass() || klass->IsPrimitive()) {
1218     __ AddU4(0);
1219   } else {
1220     __ AddU4(klass->GetObjectSize());  // instance size
1221   }
1222 
1223   __ AddU2(0);  // empty const pool
1224 
1225   // Static fields
1226   if (overhead_size == 0) {
1227     __ AddU2(static_cast<uint16_t>(0));
1228   } else {
1229     __ AddU2(static_cast<uint16_t>(num_static_fields + 1));
1230     __ AddStringId(LookupStringId(kClassOverheadName));
1231     __ AddU1(hprof_basic_object);
1232     __ AddClassStaticsId(klass);
1233 
1234     for (size_t i = 0; i < num_static_fields; ++i) {
1235       ArtField* f = klass->GetStaticField(i);
1236 
1237       size_t size;
1238       HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), &size);
1239       __ AddStringId(LookupStringId(f->GetName()));
1240       __ AddU1(t);
1241       switch (t) {
1242         case hprof_basic_byte:
1243           __ AddU1(f->GetByte(klass));
1244           break;
1245         case hprof_basic_boolean:
1246           __ AddU1(f->GetBoolean(klass));
1247           break;
1248         case hprof_basic_char:
1249           __ AddU2(f->GetChar(klass));
1250           break;
1251         case hprof_basic_short:
1252           __ AddU2(f->GetShort(klass));
1253           break;
1254         case hprof_basic_float:
1255         case hprof_basic_int:
1256         case hprof_basic_object:
1257           __ AddU4(f->Get32(klass));
1258           break;
1259         case hprof_basic_double:
1260         case hprof_basic_long:
1261           __ AddU8(f->Get64(klass));
1262           break;
1263         default:
1264           LOG(FATAL) << "Unexpected size " << size;
1265           UNREACHABLE();
1266       }
1267     }
1268   }
1269 
1270   // Instance fields for this class (no superclass fields)
1271   int iFieldCount = klass->NumInstanceFields();
1272   if (klass->IsStringClass()) {
1273     __ AddU2((uint16_t)iFieldCount + 1);
1274   } else {
1275     __ AddU2((uint16_t)iFieldCount);
1276   }
1277   for (int i = 0; i < iFieldCount; ++i) {
1278     ArtField* f = klass->GetInstanceField(i);
1279     __ AddStringId(LookupStringId(f->GetName()));
1280     HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), nullptr);
1281     __ AddU1(t);
1282   }
1283   // Add native value character array for strings / byte array for compressed strings.
1284   if (klass->IsStringClass()) {
1285     __ AddStringId(LookupStringId("value"));
1286     __ AddU1(hprof_basic_object);
1287   }
1288 }
1289 
DumpHeapArray(mirror::Array * obj,mirror::Class * klass)1290 void Hprof::DumpHeapArray(mirror::Array* obj, mirror::Class* klass) {
1291   uint32_t length = obj->GetLength();
1292 
1293   if (obj->IsObjectArray()) {
1294     // obj is an object array.
1295     __ AddU1(HPROF_OBJECT_ARRAY_DUMP);
1296 
1297     __ AddObjectId(obj);
1298     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1299     __ AddU4(length);
1300     __ AddClassId(LookupClassId(klass));
1301 
1302     // Dump the elements, which are always objects or null.
1303     __ AddIdList(obj->AsObjectArray<mirror::Object>());
1304   } else {
1305     size_t size;
1306     HprofBasicType t = SignatureToBasicTypeAndSize(
1307         Primitive::Descriptor(klass->GetComponentType()->GetPrimitiveType()), &size);
1308 
1309     // obj is a primitive array.
1310     __ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
1311 
1312     __ AddObjectId(obj);
1313     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1314     __ AddU4(length);
1315     __ AddU1(t);
1316 
1317     // Dump the raw, packed element values.
1318     if (size == 1) {
1319       __ AddU1List(reinterpret_cast<const uint8_t*>(obj->GetRawData(sizeof(uint8_t), 0)), length);
1320     } else if (size == 2) {
1321       __ AddU2List(reinterpret_cast<const uint16_t*>(obj->GetRawData(sizeof(uint16_t), 0)), length);
1322     } else if (size == 4) {
1323       __ AddU4List(reinterpret_cast<const uint32_t*>(obj->GetRawData(sizeof(uint32_t), 0)), length);
1324     } else if (size == 8) {
1325       __ AddU8List(reinterpret_cast<const uint64_t*>(obj->GetRawData(sizeof(uint64_t), 0)), length);
1326     }
1327   }
1328 }
1329 
DumpHeapInstanceObject(mirror::Object * obj,mirror::Class * klass)1330 void Hprof::DumpHeapInstanceObject(mirror::Object* obj, mirror::Class* klass) {
1331   // obj is an instance object.
1332   __ AddU1(HPROF_INSTANCE_DUMP);
1333   __ AddObjectId(obj);
1334   __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1335   __ AddClassId(LookupClassId(klass));
1336 
1337   // Reserve some space for the length of the instance data, which we won't
1338   // know until we're done writing it.
1339   size_t size_patch_offset = output_->Length();
1340   __ AddU4(0x77777777);
1341 
1342   // What we will use for the string value if the object is a string.
1343   mirror::Object* string_value = nullptr;
1344 
1345   // Write the instance data;  fields for this class, followed by super class fields, and so on.
1346   do {
1347     const size_t instance_fields = klass->NumInstanceFields();
1348     for (size_t i = 0; i < instance_fields; ++i) {
1349       ArtField* f = klass->GetInstanceField(i);
1350       size_t size;
1351       HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), &size);
1352       switch (t) {
1353       case hprof_basic_byte:
1354         __ AddU1(f->GetByte(obj));
1355         break;
1356       case hprof_basic_boolean:
1357         __ AddU1(f->GetBoolean(obj));
1358         break;
1359       case hprof_basic_char:
1360         __ AddU2(f->GetChar(obj));
1361         break;
1362       case hprof_basic_short:
1363         __ AddU2(f->GetShort(obj));
1364         break;
1365       case hprof_basic_int:
1366         if (mirror::kUseStringCompression &&
1367             klass->IsStringClass() &&
1368             f->GetOffset().SizeValue() == mirror::String::CountOffset().SizeValue()) {
1369           // Store the string length instead of the raw count field with compression flag.
1370           __ AddU4(obj->AsString()->GetLength());
1371           break;
1372         }
1373         FALLTHROUGH_INTENDED;
1374       case hprof_basic_float:
1375       case hprof_basic_object:
1376         __ AddU4(f->Get32(obj));
1377         break;
1378       case hprof_basic_double:
1379       case hprof_basic_long:
1380         __ AddU8(f->Get64(obj));
1381         break;
1382       }
1383     }
1384     // Add value field for String if necessary.
1385     if (klass->IsStringClass()) {
1386       mirror::String* s = obj->AsString();
1387       if (s->GetLength() == 0) {
1388         // If string is empty, use an object-aligned address within the string for the value.
1389         string_value = reinterpret_cast<mirror::Object*>(
1390             reinterpret_cast<uintptr_t>(s) + kObjectAlignment);
1391       } else {
1392         if (s->IsCompressed()) {
1393           string_value = reinterpret_cast<mirror::Object*>(s->GetValueCompressed());
1394         } else {
1395           string_value = reinterpret_cast<mirror::Object*>(s->GetValue());
1396         }
1397       }
1398       __ AddObjectId(string_value);
1399     }
1400 
1401     klass = klass->GetSuperClass();
1402   } while (klass != nullptr);
1403 
1404   // Patch the instance field length.
1405   __ UpdateU4(size_patch_offset, output_->Length() - (size_patch_offset + 4));
1406 
1407   // Output native value character array for strings.
1408   CHECK_EQ(obj->IsString(), string_value != nullptr);
1409   if (string_value != nullptr) {
1410     mirror::String* s = obj->AsString();
1411     __ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
1412     __ AddObjectId(string_value);
1413     __ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
1414     __ AddU4(s->GetLength());
1415     if (s->IsCompressed()) {
1416       __ AddU1(hprof_basic_byte);
1417       __ AddU1List(s->GetValueCompressed(), s->GetLength());
1418     } else {
1419       __ AddU1(hprof_basic_char);
1420       __ AddU2List(s->GetValue(), s->GetLength());
1421     }
1422   }
1423 }
1424 
VisitRoot(mirror::Object * obj,const RootInfo & info)1425 void Hprof::VisitRoot(mirror::Object* obj, const RootInfo& info) {
1426   static const HprofHeapTag xlate[] = {
1427     HPROF_ROOT_UNKNOWN,
1428     HPROF_ROOT_JNI_GLOBAL,
1429     HPROF_ROOT_JNI_LOCAL,
1430     HPROF_ROOT_JAVA_FRAME,
1431     HPROF_ROOT_NATIVE_STACK,
1432     HPROF_ROOT_STICKY_CLASS,
1433     HPROF_ROOT_THREAD_BLOCK,
1434     HPROF_ROOT_MONITOR_USED,
1435     HPROF_ROOT_THREAD_OBJECT,
1436     HPROF_ROOT_INTERNED_STRING,
1437     HPROF_ROOT_FINALIZING,
1438     HPROF_ROOT_DEBUGGER,
1439     HPROF_ROOT_REFERENCE_CLEANUP,
1440     HPROF_ROOT_VM_INTERNAL,
1441     HPROF_ROOT_JNI_MONITOR,
1442   };
1443   CHECK_LT(info.GetType(), sizeof(xlate) / sizeof(HprofHeapTag));
1444   if (obj == nullptr) {
1445     return;
1446   }
1447   MarkRootObject(obj, 0, xlate[info.GetType()], info.GetThreadId());
1448 }
1449 
1450 // If "direct_to_ddms" is true, the other arguments are ignored, and data is
1451 // sent directly to DDMS.
1452 // If "fd" is >= 0, the output will be written to that file descriptor.
1453 // Otherwise, "filename" is used to create an output file.
DumpHeap(const char * filename,int fd,bool direct_to_ddms)1454 void DumpHeap(const char* filename, int fd, bool direct_to_ddms) {
1455   CHECK(filename != nullptr);
1456   Thread* self = Thread::Current();
1457   // Need to take a heap dump while GC isn't running. See the comment in Heap::VisitObjects().
1458   // Also we need the critical section to avoid visiting the same object twice. See b/34967844
1459   gc::ScopedGCCriticalSection gcs(self,
1460                                   gc::kGcCauseHprof,
1461                                   gc::kCollectorTypeHprof);
1462   ScopedSuspendAll ssa(__FUNCTION__, true /* long suspend */);
1463   Hprof hprof(filename, fd, direct_to_ddms);
1464   hprof.Dump();
1465 }
1466 
1467 }  // namespace hprof
1468 }  // namespace art
1469