/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Preparation and completion of hprof data generation. The output is
* written into two files and then combined. This is necessary because
* we generate some of the data (strings and classes) while we dump the
* heap, and some analysis tools require that the class and string data
* appear first.
*/
#include "hprof.h"
#include <cutils/open_memstream.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <time.h>
#include <time.h>
#include <unistd.h>
#include <set>
#include "art_field-inl.h"
#include "base/logging.h"
#include "base/stringprintf.h"
#include "base/time_utils.h"
#include "base/unix_file/fd_file.h"
#include "class_linker.h"
#include "common_throws.h"
#include "debugger.h"
#include "dex_file-inl.h"
#include "gc_root.h"
#include "gc/accounting/heap_bitmap.h"
#include "gc/allocation_record.h"
#include "gc/heap.h"
#include "gc/space/space.h"
#include "globals.h"
#include "jdwp/jdwp.h"
#include "jdwp/jdwp_priv.h"
#include "mirror/class.h"
#include "mirror/class-inl.h"
#include "mirror/object-inl.h"
#include "os.h"
#include "safe_map.h"
#include "scoped_thread_state_change.h"
#include "thread_list.h"
namespace art {
namespace hprof {
static constexpr bool kDirectStream = true;
static constexpr uint32_t kHprofTime = 0;
static constexpr uint32_t kHprofNullThread = 0;
static constexpr size_t kMaxObjectsPerSegment = 128;
static constexpr size_t kMaxBytesPerSegment = 4096;
// The static field-name for the synthetic object generated to account for class static overhead.
static constexpr const char* kClassOverheadName = "$classOverhead";
enum HprofTag {
HPROF_TAG_STRING = 0x01,
HPROF_TAG_LOAD_CLASS = 0x02,
HPROF_TAG_UNLOAD_CLASS = 0x03,
HPROF_TAG_STACK_FRAME = 0x04,
HPROF_TAG_STACK_TRACE = 0x05,
HPROF_TAG_ALLOC_SITES = 0x06,
HPROF_TAG_HEAP_SUMMARY = 0x07,
HPROF_TAG_START_THREAD = 0x0A,
HPROF_TAG_END_THREAD = 0x0B,
HPROF_TAG_HEAP_DUMP = 0x0C,
HPROF_TAG_HEAP_DUMP_SEGMENT = 0x1C,
HPROF_TAG_HEAP_DUMP_END = 0x2C,
HPROF_TAG_CPU_SAMPLES = 0x0D,
HPROF_TAG_CONTROL_SETTINGS = 0x0E,
};
// Values for the first byte of HEAP_DUMP and HEAP_DUMP_SEGMENT records:
enum HprofHeapTag {
// Traditional.
HPROF_ROOT_UNKNOWN = 0xFF,
HPROF_ROOT_JNI_GLOBAL = 0x01,
HPROF_ROOT_JNI_LOCAL = 0x02,
HPROF_ROOT_JAVA_FRAME = 0x03,
HPROF_ROOT_NATIVE_STACK = 0x04,
HPROF_ROOT_STICKY_CLASS = 0x05,
HPROF_ROOT_THREAD_BLOCK = 0x06,
HPROF_ROOT_MONITOR_USED = 0x07,
HPROF_ROOT_THREAD_OBJECT = 0x08,
HPROF_CLASS_DUMP = 0x20,
HPROF_INSTANCE_DUMP = 0x21,
HPROF_OBJECT_ARRAY_DUMP = 0x22,
HPROF_PRIMITIVE_ARRAY_DUMP = 0x23,
// Android.
HPROF_HEAP_DUMP_INFO = 0xfe,
HPROF_ROOT_INTERNED_STRING = 0x89,
HPROF_ROOT_FINALIZING = 0x8a, // Obsolete.
HPROF_ROOT_DEBUGGER = 0x8b,
HPROF_ROOT_REFERENCE_CLEANUP = 0x8c, // Obsolete.
HPROF_ROOT_VM_INTERNAL = 0x8d,
HPROF_ROOT_JNI_MONITOR = 0x8e,
HPROF_UNREACHABLE = 0x90, // Obsolete.
HPROF_PRIMITIVE_ARRAY_NODATA_DUMP = 0xc3, // Obsolete.
};
enum HprofHeapId {
HPROF_HEAP_DEFAULT = 0,
HPROF_HEAP_ZYGOTE = 'Z',
HPROF_HEAP_APP = 'A',
HPROF_HEAP_IMAGE = 'I',
};
enum HprofBasicType {
hprof_basic_object = 2,
hprof_basic_boolean = 4,
hprof_basic_char = 5,
hprof_basic_float = 6,
hprof_basic_double = 7,
hprof_basic_byte = 8,
hprof_basic_short = 9,
hprof_basic_int = 10,
hprof_basic_long = 11,
};
typedef uint32_t HprofStringId;
typedef uint32_t HprofClassObjectId;
typedef uint32_t HprofClassSerialNumber;
typedef uint32_t HprofStackTraceSerialNumber;
typedef uint32_t HprofStackFrameId;
static constexpr HprofStackTraceSerialNumber kHprofNullStackTrace = 0;
class EndianOutput {
public:
EndianOutput() : length_(0), sum_length_(0), max_length_(0), started_(false) {}
virtual ~EndianOutput() {}
void StartNewRecord(uint8_t tag, uint32_t time) {
if (length_ > 0) {
EndRecord();
}
DCHECK_EQ(length_, 0U);
AddU1(tag);
AddU4(time);
AddU4(0xdeaddead); // Length, replaced on flush.
started_ = true;
}
void EndRecord() {
// Replace length in header.
if (started_) {
UpdateU4(sizeof(uint8_t) + sizeof(uint32_t),
length_ - sizeof(uint8_t) - 2 * sizeof(uint32_t));
}
HandleEndRecord();
sum_length_ += length_;
max_length_ = std::max(max_length_, length_);
length_ = 0;
started_ = false;
}
void AddU1(uint8_t value) {
AddU1List(&value, 1);
}
void AddU2(uint16_t value) {
AddU2List(&value, 1);
}
void AddU4(uint32_t value) {
AddU4List(&value, 1);
}
void AddU8(uint64_t value) {
AddU8List(&value, 1);
}
void AddObjectId(const mirror::Object* value) {
AddU4(PointerToLowMemUInt32(value));
}
void AddStackTraceSerialNumber(HprofStackTraceSerialNumber value) {
AddU4(value);
}
// The ID for the synthetic object generated to account for class static overhead.
void AddClassStaticsId(const mirror::Class* value) {
AddU4(1 | PointerToLowMemUInt32(value));
}
void AddJniGlobalRefId(jobject value) {
AddU4(PointerToLowMemUInt32(value));
}
void AddClassId(HprofClassObjectId value) {
AddU4(value);
}
void AddStringId(HprofStringId value) {
AddU4(value);
}
void AddU1List(const uint8_t* values, size_t count) {
HandleU1List(values, count);
length_ += count;
}
void AddU2List(const uint16_t* values, size_t count) {
HandleU2List(values, count);
length_ += count * sizeof(uint16_t);
}
void AddU4List(const uint32_t* values, size_t count) {
HandleU4List(values, count);
length_ += count * sizeof(uint32_t);
}
virtual void UpdateU4(size_t offset, uint32_t new_value ATTRIBUTE_UNUSED) {
DCHECK_LE(offset, length_ - 4);
}
void AddU8List(const uint64_t* values, size_t count) {
HandleU8List(values, count);
length_ += count * sizeof(uint64_t);
}
void AddIdList(mirror::ObjectArray<mirror::Object>* values)
SHARED_REQUIRES(Locks::mutator_lock_) {
const int32_t length = values->GetLength();
for (int32_t i = 0; i < length; ++i) {
AddObjectId(values->GetWithoutChecks(i));
}
}
void AddUtf8String(const char* str) {
// The terminating NUL character is NOT written.
AddU1List((const uint8_t*)str, strlen(str));
}
size_t Length() const {
return length_;
}
size_t SumLength() const {
return sum_length_;
}
size_t MaxLength() const {
return max_length_;
}
protected:
virtual void HandleU1List(const uint8_t* values ATTRIBUTE_UNUSED,
size_t count ATTRIBUTE_UNUSED) {
}
virtual void HandleU2List(const uint16_t* values ATTRIBUTE_UNUSED,
size_t count ATTRIBUTE_UNUSED) {
}
virtual void HandleU4List(const uint32_t* values ATTRIBUTE_UNUSED,
size_t count ATTRIBUTE_UNUSED) {
}
virtual void HandleU8List(const uint64_t* values ATTRIBUTE_UNUSED,
size_t count ATTRIBUTE_UNUSED) {
}
virtual void HandleEndRecord() {
}
size_t length_; // Current record size.
size_t sum_length_; // Size of all data.
size_t max_length_; // Maximum seen length.
bool started_; // Was StartRecord called?
};
// This keeps things buffered until flushed.
class EndianOutputBuffered : public EndianOutput {
public:
explicit EndianOutputBuffered(size_t reserve_size) {
buffer_.reserve(reserve_size);
}
virtual ~EndianOutputBuffered() {}
void UpdateU4(size_t offset, uint32_t new_value) OVERRIDE {
DCHECK_LE(offset, length_ - 4);
buffer_[offset + 0] = static_cast<uint8_t>((new_value >> 24) & 0xFF);
buffer_[offset + 1] = static_cast<uint8_t>((new_value >> 16) & 0xFF);
buffer_[offset + 2] = static_cast<uint8_t>((new_value >> 8) & 0xFF);
buffer_[offset + 3] = static_cast<uint8_t>((new_value >> 0) & 0xFF);
}
protected:
void HandleU1List(const uint8_t* values, size_t count) OVERRIDE {
DCHECK_EQ(length_, buffer_.size());
buffer_.insert(buffer_.end(), values, values + count);
}
void HandleU2List(const uint16_t* values, size_t count) OVERRIDE {
DCHECK_EQ(length_, buffer_.size());
for (size_t i = 0; i < count; ++i) {
uint16_t value = *values;
buffer_.push_back(static_cast<uint8_t>((value >> 8) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 0) & 0xFF));
values++;
}
}
void HandleU4List(const uint32_t* values, size_t count) OVERRIDE {
DCHECK_EQ(length_, buffer_.size());
for (size_t i = 0; i < count; ++i) {
uint32_t value = *values;
buffer_.push_back(static_cast<uint8_t>((value >> 24) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 16) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 8) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 0) & 0xFF));
values++;
}
}
void HandleU8List(const uint64_t* values, size_t count) OVERRIDE {
DCHECK_EQ(length_, buffer_.size());
for (size_t i = 0; i < count; ++i) {
uint64_t value = *values;
buffer_.push_back(static_cast<uint8_t>((value >> 56) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 48) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 40) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 32) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 24) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 16) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 8) & 0xFF));
buffer_.push_back(static_cast<uint8_t>((value >> 0) & 0xFF));
values++;
}
}
void HandleEndRecord() OVERRIDE {
DCHECK_EQ(buffer_.size(), length_);
if (kIsDebugBuild && started_) {
uint32_t stored_length =
static_cast<uint32_t>(buffer_[5]) << 24 |
static_cast<uint32_t>(buffer_[6]) << 16 |
static_cast<uint32_t>(buffer_[7]) << 8 |
static_cast<uint32_t>(buffer_[8]);
DCHECK_EQ(stored_length, length_ - sizeof(uint8_t) - 2 * sizeof(uint32_t));
}
HandleFlush(buffer_.data(), length_);
buffer_.clear();
}
virtual void HandleFlush(const uint8_t* buffer ATTRIBUTE_UNUSED, size_t length ATTRIBUTE_UNUSED) {
}
std::vector<uint8_t> buffer_;
};
class FileEndianOutput FINAL : public EndianOutputBuffered {
public:
FileEndianOutput(File* fp, size_t reserved_size)
: EndianOutputBuffered(reserved_size), fp_(fp), errors_(false) {
DCHECK(fp != nullptr);
}
~FileEndianOutput() {
}
bool Errors() {
return errors_;
}
protected:
void HandleFlush(const uint8_t* buffer, size_t length) OVERRIDE {
if (!errors_) {
errors_ = !fp_->WriteFully(buffer, length);
}
}
private:
File* fp_;
bool errors_;
};
class NetStateEndianOutput FINAL : public EndianOutputBuffered {
public:
NetStateEndianOutput(JDWP::JdwpNetStateBase* net_state, size_t reserved_size)
: EndianOutputBuffered(reserved_size), net_state_(net_state) {
DCHECK(net_state != nullptr);
}
~NetStateEndianOutput() {}
protected:
void HandleFlush(const uint8_t* buffer, size_t length) OVERRIDE {
std::vector<iovec> iov;
iov.push_back(iovec());
iov[0].iov_base = const_cast<void*>(reinterpret_cast<const void*>(buffer));
iov[0].iov_len = length;
net_state_->WriteBufferedPacketLocked(iov);
}
private:
JDWP::JdwpNetStateBase* net_state_;
};
#define __ output_->
class Hprof : public SingleRootVisitor {
public:
Hprof(const char* output_filename, int fd, bool direct_to_ddms)
: filename_(output_filename),
fd_(fd),
direct_to_ddms_(direct_to_ddms) {
LOG(INFO) << "hprof: heap dump \"" << filename_ << "\" starting...";
}
void Dump()
REQUIRES(Locks::mutator_lock_)
REQUIRES(!Locks::heap_bitmap_lock_, !Locks::alloc_tracker_lock_) {
{
MutexLock mu(Thread::Current(), *Locks::alloc_tracker_lock_);
if (Runtime::Current()->GetHeap()->IsAllocTrackingEnabled()) {
PopulateAllocationTrackingTraces();
}
}
// First pass to measure the size of the dump.
size_t overall_size;
size_t max_length;
{
EndianOutput count_output;
output_ = &count_output;
ProcessHeap(false);
overall_size = count_output.SumLength();
max_length = count_output.MaxLength();
output_ = nullptr;
}
bool okay;
if (direct_to_ddms_) {
if (kDirectStream) {
okay = DumpToDdmsDirect(overall_size, max_length, CHUNK_TYPE("HPDS"));
} else {
okay = DumpToDdmsBuffered(overall_size, max_length);
}
} else {
okay = DumpToFile(overall_size, max_length);
}
if (okay) {
const uint64_t duration = NanoTime() - start_ns_;
LOG(INFO) << "hprof: heap dump completed (" << PrettySize(RoundUp(overall_size, KB))
<< ") in " << PrettyDuration(duration)
<< " objects " << total_objects_
<< " objects with stack traces " << total_objects_with_stack_trace_;
}
}
private:
static void VisitObjectCallback(mirror::Object* obj, void* arg)
SHARED_REQUIRES(Locks::mutator_lock_) {
DCHECK(obj != nullptr);
DCHECK(arg != nullptr);
reinterpret_cast<Hprof*>(arg)->DumpHeapObject(obj);
}
void DumpHeapObject(mirror::Object* obj)
SHARED_REQUIRES(Locks::mutator_lock_);
void DumpHeapClass(mirror::Class* klass)
SHARED_REQUIRES(Locks::mutator_lock_);
void DumpHeapArray(mirror::Array* obj, mirror::Class* klass)
SHARED_REQUIRES(Locks::mutator_lock_);
void DumpHeapInstanceObject(mirror::Object* obj, mirror::Class* klass)
SHARED_REQUIRES(Locks::mutator_lock_);
void ProcessHeap(bool header_first)
REQUIRES(Locks::mutator_lock_) {
// Reset current heap and object count.
current_heap_ = HPROF_HEAP_DEFAULT;
objects_in_segment_ = 0;
if (header_first) {
ProcessHeader(true);
ProcessBody();
} else {
ProcessBody();
ProcessHeader(false);
}
}
void ProcessBody() REQUIRES(Locks::mutator_lock_) {
Runtime* const runtime = Runtime::Current();
// Walk the roots and the heap.
output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_SEGMENT, kHprofTime);
simple_roots_.clear();
runtime->VisitRoots(this);
runtime->VisitImageRoots(this);
runtime->GetHeap()->VisitObjectsPaused(VisitObjectCallback, this);
output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_END, kHprofTime);
output_->EndRecord();
}
void ProcessHeader(bool string_first) REQUIRES(Locks::mutator_lock_) {
// Write the header.
WriteFixedHeader();
// Write the string and class tables, and any stack traces, to the header.
// (jhat requires that these appear before any of the data in the body that refers to them.)
// jhat also requires the string table appear before class table and stack traces.
// However, WriteStackTraces() can modify the string table, so it's necessary to call
// WriteStringTable() last in the first pass, to compute the correct length of the output.
if (string_first) {
WriteStringTable();
}
WriteClassTable();
WriteStackTraces();
if (!string_first) {
WriteStringTable();
}
output_->EndRecord();
}
void WriteClassTable() SHARED_REQUIRES(Locks::mutator_lock_) {
for (const auto& p : classes_) {
mirror::Class* c = p.first;
HprofClassSerialNumber sn = p.second;
CHECK(c != nullptr);
output_->StartNewRecord(HPROF_TAG_LOAD_CLASS, kHprofTime);
// LOAD CLASS format:
// U4: class serial number (always > 0)
// ID: class object ID. We use the address of the class object structure as its ID.
// U4: stack trace serial number
// ID: class name string ID
__ AddU4(sn);
__ AddObjectId(c);
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(c));
__ AddStringId(LookupClassNameId(c));
}
}
void WriteStringTable() {
for (const std::pair<std::string, HprofStringId>& p : strings_) {
const std::string& string = p.first;
const size_t id = p.second;
output_->StartNewRecord(HPROF_TAG_STRING, kHprofTime);
// STRING format:
// ID: ID for this string
// U1*: UTF8 characters for string (NOT null terminated)
// (the record format encodes the length)
__ AddU4(id);
__ AddUtf8String(string.c_str());
}
}
void StartNewHeapDumpSegment() {
// This flushes the old segment and starts a new one.
output_->StartNewRecord(HPROF_TAG_HEAP_DUMP_SEGMENT, kHprofTime);
objects_in_segment_ = 0;
// Starting a new HEAP_DUMP resets the heap to default.
current_heap_ = HPROF_HEAP_DEFAULT;
}
void CheckHeapSegmentConstraints() {
if (objects_in_segment_ >= kMaxObjectsPerSegment || output_->Length() >= kMaxBytesPerSegment) {
StartNewHeapDumpSegment();
}
}
void VisitRoot(mirror::Object* obj, const RootInfo& root_info)
OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_);
void MarkRootObject(const mirror::Object* obj, jobject jni_obj, HprofHeapTag heap_tag,
uint32_t thread_serial);
HprofClassObjectId LookupClassId(mirror::Class* c) SHARED_REQUIRES(Locks::mutator_lock_) {
if (c != nullptr) {
auto it = classes_.find(c);
if (it == classes_.end()) {
// first time to see this class
HprofClassSerialNumber sn = next_class_serial_number_++;
classes_.Put(c, sn);
// Make sure that we've assigned a string ID for this class' name
LookupClassNameId(c);
}
}
return PointerToLowMemUInt32(c);
}
HprofStackTraceSerialNumber LookupStackTraceSerialNumber(const mirror::Object* obj)
SHARED_REQUIRES(Locks::mutator_lock_) {
auto r = allocation_records_.find(obj);
if (r == allocation_records_.end()) {
return kHprofNullStackTrace;
} else {
const gc::AllocRecordStackTrace* trace = r->second;
auto result = traces_.find(trace);
CHECK(result != traces_.end());
return result->second;
}
}
HprofStringId LookupStringId(mirror::String* string) SHARED_REQUIRES(Locks::mutator_lock_) {
return LookupStringId(string->ToModifiedUtf8());
}
HprofStringId LookupStringId(const char* string) {
return LookupStringId(std::string(string));
}
HprofStringId LookupStringId(const std::string& string) {
auto it = strings_.find(string);
if (it != strings_.end()) {
return it->second;
}
HprofStringId id = next_string_id_++;
strings_.Put(string, id);
return id;
}
HprofStringId LookupClassNameId(mirror::Class* c) SHARED_REQUIRES(Locks::mutator_lock_) {
return LookupStringId(PrettyDescriptor(c));
}
void WriteFixedHeader() {
// Write the file header.
// U1: NUL-terminated magic string.
const char magic[] = "JAVA PROFILE 1.0.3";
__ AddU1List(reinterpret_cast<const uint8_t*>(magic), sizeof(magic));
// U4: size of identifiers. We're using addresses as IDs and our heap references are stored
// as uint32_t.
// Note of warning: hprof-conv hard-codes the size of identifiers to 4.
static_assert(sizeof(mirror::HeapReference<mirror::Object>) == sizeof(uint32_t),
"Unexpected HeapReference size");
__ AddU4(sizeof(uint32_t));
// The current time, in milliseconds since 0:00 GMT, 1/1/70.
timeval now;
const uint64_t nowMs = (gettimeofday(&now, nullptr) < 0) ? 0 :
(uint64_t)now.tv_sec * 1000 + now.tv_usec / 1000;
// TODO: It seems it would be correct to use U8.
// U4: high word of the 64-bit time.
__ AddU4(static_cast<uint32_t>(nowMs >> 32));
// U4: low word of the 64-bit time.
__ AddU4(static_cast<uint32_t>(nowMs & 0xFFFFFFFF));
}
void WriteStackTraces() SHARED_REQUIRES(Locks::mutator_lock_) {
// Write a dummy stack trace record so the analysis tools don't freak out.
output_->StartNewRecord(HPROF_TAG_STACK_TRACE, kHprofTime);
__ AddStackTraceSerialNumber(kHprofNullStackTrace);
__ AddU4(kHprofNullThread);
__ AddU4(0); // no frames
// TODO: jhat complains "WARNING: Stack trace not found for serial # -1", but no trace should
// have -1 as its serial number (as long as HprofStackTraceSerialNumber doesn't overflow).
for (const auto& it : traces_) {
const gc::AllocRecordStackTrace* trace = it.first;
HprofStackTraceSerialNumber trace_sn = it.second;
size_t depth = trace->GetDepth();
// First write stack frames of the trace
for (size_t i = 0; i < depth; ++i) {
const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
ArtMethod* method = frame->GetMethod();
CHECK(method != nullptr);
output_->StartNewRecord(HPROF_TAG_STACK_FRAME, kHprofTime);
// STACK FRAME format:
// ID: stack frame ID. We use the address of the AllocRecordStackTraceElement object as its ID.
// ID: method name string ID
// ID: method signature string ID
// ID: source file name string ID
// U4: class serial number
// U4: >0, line number; 0, no line information available; -1, unknown location
auto frame_result = frames_.find(frame);
CHECK(frame_result != frames_.end());
__ AddU4(frame_result->second);
__ AddStringId(LookupStringId(method->GetName()));
__ AddStringId(LookupStringId(method->GetSignature().ToString()));
const char* source_file = method->GetDeclaringClassSourceFile();
if (source_file == nullptr) {
source_file = "";
}
__ AddStringId(LookupStringId(source_file));
auto class_result = classes_.find(method->GetDeclaringClass());
CHECK(class_result != classes_.end());
__ AddU4(class_result->second);
__ AddU4(frame->ComputeLineNumber());
}
// Then write the trace itself
output_->StartNewRecord(HPROF_TAG_STACK_TRACE, kHprofTime);
// STACK TRACE format:
// U4: stack trace serial number. We use the address of the AllocRecordStackTrace object as its serial number.
// U4: thread serial number. We use Thread::GetTid().
// U4: number of frames
// [ID]*: series of stack frame ID's
__ AddStackTraceSerialNumber(trace_sn);
__ AddU4(trace->GetTid());
__ AddU4(depth);
for (size_t i = 0; i < depth; ++i) {
const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
auto frame_result = frames_.find(frame);
CHECK(frame_result != frames_.end());
__ AddU4(frame_result->second);
}
}
}
bool DumpToDdmsBuffered(size_t overall_size ATTRIBUTE_UNUSED, size_t max_length ATTRIBUTE_UNUSED)
REQUIRES(Locks::mutator_lock_) {
LOG(FATAL) << "Unimplemented";
UNREACHABLE();
// // Send the data off to DDMS.
// iovec iov[2];
// iov[0].iov_base = header_data_ptr_;
// iov[0].iov_len = header_data_size_;
// iov[1].iov_base = body_data_ptr_;
// iov[1].iov_len = body_data_size_;
// Dbg::DdmSendChunkV(CHUNK_TYPE("HPDS"), iov, 2);
}
bool DumpToFile(size_t overall_size, size_t max_length)
REQUIRES(Locks::mutator_lock_) {
// Where exactly are we writing to?
int out_fd;
if (fd_ >= 0) {
out_fd = dup(fd_);
if (out_fd < 0) {
ThrowRuntimeException("Couldn't dump heap; dup(%d) failed: %s", fd_, strerror(errno));
return false;
}
} else {
out_fd = open(filename_.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0644);
if (out_fd < 0) {
ThrowRuntimeException("Couldn't dump heap; open(\"%s\") failed: %s", filename_.c_str(),
strerror(errno));
return false;
}
}
std::unique_ptr<File> file(new File(out_fd, filename_, true));
bool okay;
{
FileEndianOutput file_output(file.get(), max_length);
output_ = &file_output;
ProcessHeap(true);
okay = !file_output.Errors();
if (okay) {
// Check for expected size. Output is expected to be less-or-equal than first phase, see
// b/23521263.
DCHECK_LE(file_output.SumLength(), overall_size);
}
output_ = nullptr;
}
if (okay) {
okay = file->FlushCloseOrErase() == 0;
} else {
file->Erase();
}
if (!okay) {
std::string msg(StringPrintf("Couldn't dump heap; writing \"%s\" failed: %s",
filename_.c_str(), strerror(errno)));
ThrowRuntimeException("%s", msg.c_str());
LOG(ERROR) << msg;
}
return okay;
}
bool DumpToDdmsDirect(size_t overall_size, size_t max_length, uint32_t chunk_type)
REQUIRES(Locks::mutator_lock_) {
CHECK(direct_to_ddms_);
JDWP::JdwpState* state = Dbg::GetJdwpState();
CHECK(state != nullptr);
JDWP::JdwpNetStateBase* net_state = state->netState;
CHECK(net_state != nullptr);
// Hold the socket lock for the whole time since we want this to be atomic.
MutexLock mu(Thread::Current(), *net_state->GetSocketLock());
// Prepare the Ddms chunk.
constexpr size_t kChunkHeaderSize = kJDWPHeaderLen + 8;
uint8_t chunk_header[kChunkHeaderSize] = { 0 };
state->SetupChunkHeader(chunk_type, overall_size, kChunkHeaderSize, chunk_header);
// Prepare the output and send the chunk header.
NetStateEndianOutput net_output(net_state, max_length);
output_ = &net_output;
net_output.AddU1List(chunk_header, kChunkHeaderSize);
// Write the dump.
ProcessHeap(true);
// Check for expected size. See DumpToFile for comment.
DCHECK_LE(net_output.SumLength(), overall_size + kChunkHeaderSize);
output_ = nullptr;
return true;
}
void PopulateAllocationTrackingTraces()
REQUIRES(Locks::mutator_lock_, Locks::alloc_tracker_lock_) {
gc::AllocRecordObjectMap* records = Runtime::Current()->GetHeap()->GetAllocationRecords();
CHECK(records != nullptr);
HprofStackTraceSerialNumber next_trace_sn = kHprofNullStackTrace + 1;
HprofStackFrameId next_frame_id = 0;
size_t count = 0;
for (auto it = records->Begin(), end = records->End(); it != end; ++it) {
const mirror::Object* obj = it->first.Read();
if (obj == nullptr) {
continue;
}
++count;
const gc::AllocRecordStackTrace* trace = it->second.GetStackTrace();
// Copy the pair into a real hash map to speed up look up.
auto records_result = allocation_records_.emplace(obj, trace);
// The insertion should always succeed, i.e. no duplicate object pointers in "records"
CHECK(records_result.second);
// Generate serial numbers for traces, and IDs for frames.
auto traces_result = traces_.find(trace);
if (traces_result == traces_.end()) {
traces_.emplace(trace, next_trace_sn++);
// only check frames if the trace is newly discovered
for (size_t i = 0, depth = trace->GetDepth(); i < depth; ++i) {
const gc::AllocRecordStackTraceElement* frame = &trace->GetStackElement(i);
auto frames_result = frames_.find(frame);
if (frames_result == frames_.end()) {
frames_.emplace(frame, next_frame_id++);
}
}
}
}
CHECK_EQ(traces_.size(), next_trace_sn - kHprofNullStackTrace - 1);
CHECK_EQ(frames_.size(), next_frame_id);
total_objects_with_stack_trace_ = count;
}
// If direct_to_ddms_ is set, "filename_" and "fd" will be ignored.
// Otherwise, "filename_" must be valid, though if "fd" >= 0 it will
// only be used for debug messages.
std::string filename_;
int fd_;
bool direct_to_ddms_;
uint64_t start_ns_ = NanoTime();
EndianOutput* output_ = nullptr;
HprofHeapId current_heap_ = HPROF_HEAP_DEFAULT; // Which heap we're currently dumping.
size_t objects_in_segment_ = 0;
size_t total_objects_ = 0u;
size_t total_objects_with_stack_trace_ = 0u;
HprofStringId next_string_id_ = 0x400000;
SafeMap<std::string, HprofStringId> strings_;
HprofClassSerialNumber next_class_serial_number_ = 1;
SafeMap<mirror::Class*, HprofClassSerialNumber> classes_;
std::unordered_map<const gc::AllocRecordStackTrace*, HprofStackTraceSerialNumber,
gc::HashAllocRecordTypesPtr<gc::AllocRecordStackTrace>,
gc::EqAllocRecordTypesPtr<gc::AllocRecordStackTrace>> traces_;
std::unordered_map<const gc::AllocRecordStackTraceElement*, HprofStackFrameId,
gc::HashAllocRecordTypesPtr<gc::AllocRecordStackTraceElement>,
gc::EqAllocRecordTypesPtr<gc::AllocRecordStackTraceElement>> frames_;
std::unordered_map<const mirror::Object*, const gc::AllocRecordStackTrace*> allocation_records_;
// Set used to keep track of what simple root records we have already
// emitted, to avoid emitting duplicate entries. The simple root records are
// those that contain no other information than the root type and the object
// id. A pair of root type and object id is packed into a uint64_t, with
// the root type in the upper 32 bits and the object id in the lower 32
// bits.
std::unordered_set<uint64_t> simple_roots_;
friend class GcRootVisitor;
DISALLOW_COPY_AND_ASSIGN(Hprof);
};
static HprofBasicType SignatureToBasicTypeAndSize(const char* sig, size_t* size_out) {
char c = sig[0];
HprofBasicType ret;
size_t size;
switch (c) {
case '[':
case 'L':
ret = hprof_basic_object;
size = 4;
break;
case 'Z':
ret = hprof_basic_boolean;
size = 1;
break;
case 'C':
ret = hprof_basic_char;
size = 2;
break;
case 'F':
ret = hprof_basic_float;
size = 4;
break;
case 'D':
ret = hprof_basic_double;
size = 8;
break;
case 'B':
ret = hprof_basic_byte;
size = 1;
break;
case 'S':
ret = hprof_basic_short;
size = 2;
break;
case 'I':
ret = hprof_basic_int;
size = 4;
break;
case 'J':
ret = hprof_basic_long;
size = 8;
break;
default:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
}
if (size_out != nullptr) {
*size_out = size;
}
return ret;
}
// Always called when marking objects, but only does
// something when ctx->gc_scan_state_ is non-zero, which is usually
// only true when marking the root set or unreachable
// objects. Used to add rootset references to obj.
void Hprof::MarkRootObject(const mirror::Object* obj, jobject jni_obj, HprofHeapTag heap_tag,
uint32_t thread_serial) {
if (heap_tag == 0) {
return;
}
CheckHeapSegmentConstraints();
switch (heap_tag) {
// ID: object ID
case HPROF_ROOT_UNKNOWN:
case HPROF_ROOT_STICKY_CLASS:
case HPROF_ROOT_MONITOR_USED:
case HPROF_ROOT_INTERNED_STRING:
case HPROF_ROOT_DEBUGGER:
case HPROF_ROOT_VM_INTERNAL: {
uint64_t key = (static_cast<uint64_t>(heap_tag) << 32) | PointerToLowMemUInt32(obj);
if (simple_roots_.insert(key).second) {
__ AddU1(heap_tag);
__ AddObjectId(obj);
}
break;
}
// ID: object ID
// ID: JNI global ref ID
case HPROF_ROOT_JNI_GLOBAL:
__ AddU1(heap_tag);
__ AddObjectId(obj);
__ AddJniGlobalRefId(jni_obj);
break;
// ID: object ID
// U4: thread serial number
// U4: frame number in stack trace (-1 for empty)
case HPROF_ROOT_JNI_LOCAL:
case HPROF_ROOT_JNI_MONITOR:
case HPROF_ROOT_JAVA_FRAME:
__ AddU1(heap_tag);
__ AddObjectId(obj);
__ AddU4(thread_serial);
__ AddU4((uint32_t)-1);
break;
// ID: object ID
// U4: thread serial number
case HPROF_ROOT_NATIVE_STACK:
case HPROF_ROOT_THREAD_BLOCK:
__ AddU1(heap_tag);
__ AddObjectId(obj);
__ AddU4(thread_serial);
break;
// ID: thread object ID
// U4: thread serial number
// U4: stack trace serial number
case HPROF_ROOT_THREAD_OBJECT:
__ AddU1(heap_tag);
__ AddObjectId(obj);
__ AddU4(thread_serial);
__ AddU4((uint32_t)-1); // xxx
break;
case HPROF_CLASS_DUMP:
case HPROF_INSTANCE_DUMP:
case HPROF_OBJECT_ARRAY_DUMP:
case HPROF_PRIMITIVE_ARRAY_DUMP:
case HPROF_HEAP_DUMP_INFO:
case HPROF_PRIMITIVE_ARRAY_NODATA_DUMP:
// Ignored.
break;
case HPROF_ROOT_FINALIZING:
case HPROF_ROOT_REFERENCE_CLEANUP:
case HPROF_UNREACHABLE:
LOG(FATAL) << "obsolete tag " << static_cast<int>(heap_tag);
break;
}
++objects_in_segment_;
}
// Use for visiting the GcRoots held live by ArtFields, ArtMethods, and ClassLoaders.
class GcRootVisitor {
public:
explicit GcRootVisitor(Hprof* hprof) : hprof_(hprof) {}
void operator()(mirror::Object* obj ATTRIBUTE_UNUSED,
MemberOffset offset ATTRIBUTE_UNUSED,
bool is_static ATTRIBUTE_UNUSED) const {}
// Note that these don't have read barriers. Its OK however since the GC is guaranteed to not be
// running during the hprof dumping process.
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
SHARED_REQUIRES(Locks::mutator_lock_) {
if (!root->IsNull()) {
VisitRoot(root);
}
}
void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
SHARED_REQUIRES(Locks::mutator_lock_) {
mirror::Object* obj = root->AsMirrorPtr();
// The two cases are either classes or dex cache arrays. If it is a dex cache array, then use
// VM internal. Otherwise the object is a declaring class of an ArtField or ArtMethod or a
// class from a ClassLoader.
hprof_->VisitRoot(obj, RootInfo(obj->IsClass() ? kRootStickyClass : kRootVMInternal));
}
private:
Hprof* const hprof_;
};
void Hprof::DumpHeapObject(mirror::Object* obj) {
// Ignore classes that are retired.
if (obj->IsClass() && obj->AsClass()->IsRetired()) {
return;
}
++total_objects_;
GcRootVisitor visitor(this);
obj->VisitReferences(visitor, VoidFunctor());
gc::Heap* const heap = Runtime::Current()->GetHeap();
const gc::space::ContinuousSpace* const space = heap->FindContinuousSpaceFromObject(obj, true);
HprofHeapId heap_type = HPROF_HEAP_APP;
if (space != nullptr) {
if (space->IsZygoteSpace()) {
heap_type = HPROF_HEAP_ZYGOTE;
} else if (space->IsImageSpace()) {
heap_type = HPROF_HEAP_IMAGE;
}
} else {
const auto* los = heap->GetLargeObjectsSpace();
if (los->Contains(obj) && los->IsZygoteLargeObject(Thread::Current(), obj)) {
heap_type = HPROF_HEAP_ZYGOTE;
}
}
CheckHeapSegmentConstraints();
if (heap_type != current_heap_) {
HprofStringId nameId;
// This object is in a different heap than the current one.
// Emit a HEAP_DUMP_INFO tag to change heaps.
__ AddU1(HPROF_HEAP_DUMP_INFO);
__ AddU4(static_cast<uint32_t>(heap_type)); // uint32_t: heap type
switch (heap_type) {
case HPROF_HEAP_APP:
nameId = LookupStringId("app");
break;
case HPROF_HEAP_ZYGOTE:
nameId = LookupStringId("zygote");
break;
case HPROF_HEAP_IMAGE:
nameId = LookupStringId("image");
break;
default:
// Internal error
LOG(ERROR) << "Unexpected desiredHeap";
nameId = LookupStringId("<ILLEGAL>");
break;
}
__ AddStringId(nameId);
current_heap_ = heap_type;
}
mirror::Class* c = obj->GetClass();
if (c == nullptr) {
// This object will bother HprofReader, because it has a null
// class, so just don't dump it. It could be
// gDvm.unlinkedJavaLangClass or it could be an object just
// allocated which hasn't been initialized yet.
} else {
if (obj->IsClass()) {
DumpHeapClass(obj->AsClass());
} else if (c->IsArrayClass()) {
DumpHeapArray(obj->AsArray(), c);
} else {
DumpHeapInstanceObject(obj, c);
}
}
++objects_in_segment_;
}
void Hprof::DumpHeapClass(mirror::Class* klass) {
if (!klass->IsLoaded() && !klass->IsErroneous()) {
// Class is allocated but not yet loaded: we cannot access its fields or super class.
return;
}
const size_t num_static_fields = klass->NumStaticFields();
// Total class size including embedded IMT, embedded vtable, and static fields.
const size_t class_size = klass->GetClassSize();
// Class size excluding static fields (relies on reference fields being the first static fields).
const size_t class_size_without_overhead = sizeof(mirror::Class);
CHECK_LE(class_size_without_overhead, class_size);
const size_t overhead_size = class_size - class_size_without_overhead;
if (overhead_size != 0) {
// Create a byte array to reflect the allocation of the
// StaticField array at the end of this class.
__ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
__ AddClassStaticsId(klass);
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(klass));
__ AddU4(overhead_size);
__ AddU1(hprof_basic_byte);
for (size_t i = 0; i < overhead_size; ++i) {
__ AddU1(0);
}
}
__ AddU1(HPROF_CLASS_DUMP);
__ AddClassId(LookupClassId(klass));
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(klass));
__ AddClassId(LookupClassId(klass->GetSuperClass()));
__ AddObjectId(klass->GetClassLoader());
__ AddObjectId(nullptr); // no signer
__ AddObjectId(nullptr); // no prot domain
__ AddObjectId(nullptr); // reserved
__ AddObjectId(nullptr); // reserved
if (klass->IsClassClass()) {
// ClassObjects have their static fields appended, so aren't all the same size.
// But they're at least this size.
__ AddU4(class_size_without_overhead); // instance size
} else if (klass->IsStringClass()) {
// Strings are variable length with character data at the end like arrays.
// This outputs the size of an empty string.
__ AddU4(sizeof(mirror::String));
} else if (klass->IsArrayClass() || klass->IsPrimitive()) {
__ AddU4(0);
} else {
__ AddU4(klass->GetObjectSize()); // instance size
}
__ AddU2(0); // empty const pool
// Static fields
if (overhead_size == 0) {
__ AddU2(static_cast<uint16_t>(0));
} else {
__ AddU2(static_cast<uint16_t>(num_static_fields + 1));
__ AddStringId(LookupStringId(kClassOverheadName));
__ AddU1(hprof_basic_object);
__ AddClassStaticsId(klass);
for (size_t i = 0; i < num_static_fields; ++i) {
ArtField* f = klass->GetStaticField(i);
size_t size;
HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), &size);
__ AddStringId(LookupStringId(f->GetName()));
__ AddU1(t);
switch (t) {
case hprof_basic_byte:
__ AddU1(f->GetByte(klass));
break;
case hprof_basic_boolean:
__ AddU1(f->GetBoolean(klass));
break;
case hprof_basic_char:
__ AddU2(f->GetChar(klass));
break;
case hprof_basic_short:
__ AddU2(f->GetShort(klass));
break;
case hprof_basic_float:
case hprof_basic_int:
case hprof_basic_object:
__ AddU4(f->Get32(klass));
break;
case hprof_basic_double:
case hprof_basic_long:
__ AddU8(f->Get64(klass));
break;
default:
LOG(FATAL) << "Unexpected size " << size;
UNREACHABLE();
}
}
}
// Instance fields for this class (no superclass fields)
int iFieldCount = klass->NumInstanceFields();
if (klass->IsStringClass()) {
__ AddU2((uint16_t)iFieldCount + 1);
} else {
__ AddU2((uint16_t)iFieldCount);
}
for (int i = 0; i < iFieldCount; ++i) {
ArtField* f = klass->GetInstanceField(i);
__ AddStringId(LookupStringId(f->GetName()));
HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), nullptr);
__ AddU1(t);
}
// Add native value character array for strings.
if (klass->IsStringClass()) {
__ AddStringId(LookupStringId("value"));
__ AddU1(hprof_basic_object);
}
}
void Hprof::DumpHeapArray(mirror::Array* obj, mirror::Class* klass) {
uint32_t length = obj->GetLength();
if (obj->IsObjectArray()) {
// obj is an object array.
__ AddU1(HPROF_OBJECT_ARRAY_DUMP);
__ AddObjectId(obj);
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
__ AddU4(length);
__ AddClassId(LookupClassId(klass));
// Dump the elements, which are always objects or null.
__ AddIdList(obj->AsObjectArray<mirror::Object>());
} else {
size_t size;
HprofBasicType t = SignatureToBasicTypeAndSize(
Primitive::Descriptor(klass->GetComponentType()->GetPrimitiveType()), &size);
// obj is a primitive array.
__ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
__ AddObjectId(obj);
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
__ AddU4(length);
__ AddU1(t);
// Dump the raw, packed element values.
if (size == 1) {
__ AddU1List(reinterpret_cast<const uint8_t*>(obj->GetRawData(sizeof(uint8_t), 0)), length);
} else if (size == 2) {
__ AddU2List(reinterpret_cast<const uint16_t*>(obj->GetRawData(sizeof(uint16_t), 0)), length);
} else if (size == 4) {
__ AddU4List(reinterpret_cast<const uint32_t*>(obj->GetRawData(sizeof(uint32_t), 0)), length);
} else if (size == 8) {
__ AddU8List(reinterpret_cast<const uint64_t*>(obj->GetRawData(sizeof(uint64_t), 0)), length);
}
}
}
void Hprof::DumpHeapInstanceObject(mirror::Object* obj, mirror::Class* klass) {
// obj is an instance object.
__ AddU1(HPROF_INSTANCE_DUMP);
__ AddObjectId(obj);
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
__ AddClassId(LookupClassId(klass));
// Reserve some space for the length of the instance data, which we won't
// know until we're done writing it.
size_t size_patch_offset = output_->Length();
__ AddU4(0x77777777);
// What we will use for the string value if the object is a string.
mirror::Object* string_value = nullptr;
// Write the instance data; fields for this class, followed by super class fields, and so on.
do {
const size_t instance_fields = klass->NumInstanceFields();
for (size_t i = 0; i < instance_fields; ++i) {
ArtField* f = klass->GetInstanceField(i);
size_t size;
HprofBasicType t = SignatureToBasicTypeAndSize(f->GetTypeDescriptor(), &size);
switch (t) {
case hprof_basic_byte:
__ AddU1(f->GetByte(obj));
break;
case hprof_basic_boolean:
__ AddU1(f->GetBoolean(obj));
break;
case hprof_basic_char:
__ AddU2(f->GetChar(obj));
break;
case hprof_basic_short:
__ AddU2(f->GetShort(obj));
break;
case hprof_basic_float:
case hprof_basic_int:
case hprof_basic_object:
__ AddU4(f->Get32(obj));
break;
case hprof_basic_double:
case hprof_basic_long:
__ AddU8(f->Get64(obj));
break;
}
}
// Add value field for String if necessary.
if (klass->IsStringClass()) {
mirror::String* s = obj->AsString();
if (s->GetLength() == 0) {
// If string is empty, use an object-aligned address within the string for the value.
string_value = reinterpret_cast<mirror::Object*>(
reinterpret_cast<uintptr_t>(s) + kObjectAlignment);
} else {
string_value = reinterpret_cast<mirror::Object*>(s->GetValue());
}
__ AddObjectId(string_value);
}
klass = klass->GetSuperClass();
} while (klass != nullptr);
// Patch the instance field length.
__ UpdateU4(size_patch_offset, output_->Length() - (size_patch_offset + 4));
// Output native value character array for strings.
CHECK_EQ(obj->IsString(), string_value != nullptr);
if (string_value != nullptr) {
mirror::String* s = obj->AsString();
__ AddU1(HPROF_PRIMITIVE_ARRAY_DUMP);
__ AddObjectId(string_value);
__ AddStackTraceSerialNumber(LookupStackTraceSerialNumber(obj));
__ AddU4(s->GetLength());
__ AddU1(hprof_basic_char);
__ AddU2List(s->GetValue(), s->GetLength());
}
}
void Hprof::VisitRoot(mirror::Object* obj, const RootInfo& info) {
static const HprofHeapTag xlate[] = {
HPROF_ROOT_UNKNOWN,
HPROF_ROOT_JNI_GLOBAL,
HPROF_ROOT_JNI_LOCAL,
HPROF_ROOT_JAVA_FRAME,
HPROF_ROOT_NATIVE_STACK,
HPROF_ROOT_STICKY_CLASS,
HPROF_ROOT_THREAD_BLOCK,
HPROF_ROOT_MONITOR_USED,
HPROF_ROOT_THREAD_OBJECT,
HPROF_ROOT_INTERNED_STRING,
HPROF_ROOT_FINALIZING,
HPROF_ROOT_DEBUGGER,
HPROF_ROOT_REFERENCE_CLEANUP,
HPROF_ROOT_VM_INTERNAL,
HPROF_ROOT_JNI_MONITOR,
};
CHECK_LT(info.GetType(), sizeof(xlate) / sizeof(HprofHeapTag));
if (obj == nullptr) {
return;
}
MarkRootObject(obj, 0, xlate[info.GetType()], info.GetThreadId());
}
// If "direct_to_ddms" is true, the other arguments are ignored, and data is
// sent directly to DDMS.
// If "fd" is >= 0, the output will be written to that file descriptor.
// Otherwise, "filename" is used to create an output file.
void DumpHeap(const char* filename, int fd, bool direct_to_ddms) {
CHECK(filename != nullptr);
Thread* self = Thread::Current();
gc::Heap* heap = Runtime::Current()->GetHeap();
if (heap->IsGcConcurrentAndMoving()) {
// Need to take a heap dump while GC isn't running. See the
// comment in Heap::VisitObjects().
heap->IncrementDisableMovingGC(self);
}
{
ScopedSuspendAll ssa(__FUNCTION__, true /* long suspend */);
Hprof hprof(filename, fd, direct_to_ddms);
hprof.Dump();
}
if (heap->IsGcConcurrentAndMoving()) {
heap->DecrementDisableMovingGC(self);
}
}
} // namespace hprof
} // namespace art