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1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/profiler/allocation-tracker.h"
6 
7 #include "src/frames-inl.h"
8 #include "src/objects-inl.h"
9 #include "src/profiler/heap-snapshot-generator-inl.h"
10 
11 namespace v8 {
12 namespace internal {
13 
AllocationTraceNode(AllocationTraceTree * tree,unsigned function_info_index)14 AllocationTraceNode::AllocationTraceNode(
15     AllocationTraceTree* tree, unsigned function_info_index)
16     : tree_(tree),
17       function_info_index_(function_info_index),
18       total_size_(0),
19       allocation_count_(0),
20       id_(tree->next_node_id()) {
21 }
22 
23 
~AllocationTraceNode()24 AllocationTraceNode::~AllocationTraceNode() {
25   for (int i = 0; i < children_.length(); i++) delete children_[i];
26 }
27 
28 
FindChild(unsigned function_info_index)29 AllocationTraceNode* AllocationTraceNode::FindChild(
30     unsigned function_info_index) {
31   for (int i = 0; i < children_.length(); i++) {
32     AllocationTraceNode* node = children_[i];
33     if (node->function_info_index() == function_info_index) return node;
34   }
35   return NULL;
36 }
37 
38 
FindOrAddChild(unsigned function_info_index)39 AllocationTraceNode* AllocationTraceNode::FindOrAddChild(
40     unsigned function_info_index) {
41   AllocationTraceNode* child = FindChild(function_info_index);
42   if (child == NULL) {
43     child = new AllocationTraceNode(tree_, function_info_index);
44     children_.Add(child);
45   }
46   return child;
47 }
48 
49 
AddAllocation(unsigned size)50 void AllocationTraceNode::AddAllocation(unsigned size) {
51   total_size_ += size;
52   ++allocation_count_;
53 }
54 
55 
Print(int indent,AllocationTracker * tracker)56 void AllocationTraceNode::Print(int indent, AllocationTracker* tracker) {
57   base::OS::Print("%10u %10u %*c", total_size_, allocation_count_, indent, ' ');
58   if (tracker != NULL) {
59     AllocationTracker::FunctionInfo* info =
60         tracker->function_info_list()[function_info_index_];
61     base::OS::Print("%s #%u", info->name, id_);
62   } else {
63     base::OS::Print("%u #%u", function_info_index_, id_);
64   }
65   base::OS::Print("\n");
66   indent += 2;
67   for (int i = 0; i < children_.length(); i++) {
68     children_[i]->Print(indent, tracker);
69   }
70 }
71 
72 
AllocationTraceTree()73 AllocationTraceTree::AllocationTraceTree()
74     : next_node_id_(1),
75       root_(this, 0) {
76 }
77 
78 
~AllocationTraceTree()79 AllocationTraceTree::~AllocationTraceTree() {
80 }
81 
82 
AddPathFromEnd(const Vector<unsigned> & path)83 AllocationTraceNode* AllocationTraceTree::AddPathFromEnd(
84     const Vector<unsigned>& path) {
85   AllocationTraceNode* node = root();
86   for (unsigned* entry = path.start() + path.length() - 1;
87        entry != path.start() - 1;
88        --entry) {
89     node = node->FindOrAddChild(*entry);
90   }
91   return node;
92 }
93 
94 
Print(AllocationTracker * tracker)95 void AllocationTraceTree::Print(AllocationTracker* tracker) {
96   base::OS::Print("[AllocationTraceTree:]\n");
97   base::OS::Print("Total size | Allocation count | Function id | id\n");
98   root()->Print(0, tracker);
99 }
100 
101 
DeleteUnresolvedLocation(UnresolvedLocation ** location)102 void AllocationTracker::DeleteUnresolvedLocation(
103     UnresolvedLocation** location) {
104   delete *location;
105 }
106 
107 
FunctionInfo()108 AllocationTracker::FunctionInfo::FunctionInfo()
109     : name(""),
110       function_id(0),
111       script_name(""),
112       script_id(0),
113       line(-1),
114       column(-1) {
115 }
116 
117 
AddRange(Address start,int size,unsigned trace_node_id)118 void AddressToTraceMap::AddRange(Address start, int size,
119                                  unsigned trace_node_id) {
120   Address end = start + size;
121   RemoveRange(start, end);
122 
123   RangeStack new_range(start, trace_node_id);
124   ranges_.insert(RangeMap::value_type(end, new_range));
125 }
126 
127 
GetTraceNodeId(Address addr)128 unsigned AddressToTraceMap::GetTraceNodeId(Address addr) {
129   RangeMap::const_iterator it = ranges_.upper_bound(addr);
130   if (it == ranges_.end()) return 0;
131   if (it->second.start <= addr) {
132     return it->second.trace_node_id;
133   }
134   return 0;
135 }
136 
137 
MoveObject(Address from,Address to,int size)138 void AddressToTraceMap::MoveObject(Address from, Address to, int size) {
139   unsigned trace_node_id = GetTraceNodeId(from);
140   if (trace_node_id == 0) return;
141   RemoveRange(from, from + size);
142   AddRange(to, size, trace_node_id);
143 }
144 
145 
Clear()146 void AddressToTraceMap::Clear() {
147   ranges_.clear();
148 }
149 
150 
Print()151 void AddressToTraceMap::Print() {
152   PrintF("[AddressToTraceMap (%" PRIuS "): \n", ranges_.size());
153   for (RangeMap::iterator it = ranges_.begin(); it != ranges_.end(); ++it) {
154     PrintF("[%p - %p] => %u\n", static_cast<void*>(it->second.start),
155            static_cast<void*>(it->first), it->second.trace_node_id);
156   }
157   PrintF("]\n");
158 }
159 
160 
RemoveRange(Address start,Address end)161 void AddressToTraceMap::RemoveRange(Address start, Address end) {
162   RangeMap::iterator it = ranges_.upper_bound(start);
163   if (it == ranges_.end()) return;
164 
165   RangeStack prev_range(0, 0);
166 
167   RangeMap::iterator to_remove_begin = it;
168   if (it->second.start < start) {
169     prev_range = it->second;
170   }
171   do {
172     if (it->first > end) {
173       if (it->second.start < end) {
174         it->second.start = end;
175       }
176       break;
177     }
178     ++it;
179   } while (it != ranges_.end());
180 
181   ranges_.erase(to_remove_begin, it);
182 
183   if (prev_range.start != 0) {
184     ranges_.insert(RangeMap::value_type(start, prev_range));
185   }
186 }
187 
188 
DeleteFunctionInfo(FunctionInfo ** info)189 void AllocationTracker::DeleteFunctionInfo(FunctionInfo** info) {
190     delete *info;
191 }
192 
AllocationTracker(HeapObjectsMap * ids,StringsStorage * names)193 AllocationTracker::AllocationTracker(HeapObjectsMap* ids, StringsStorage* names)
194     : ids_(ids),
195       names_(names),
196       id_to_function_info_index_(),
197       info_index_for_other_state_(0) {
198   FunctionInfo* info = new FunctionInfo();
199   info->name = "(root)";
200   function_info_list_.Add(info);
201 }
202 
203 
~AllocationTracker()204 AllocationTracker::~AllocationTracker() {
205   unresolved_locations_.Iterate(DeleteUnresolvedLocation);
206   function_info_list_.Iterate(&DeleteFunctionInfo);
207 }
208 
209 
PrepareForSerialization()210 void AllocationTracker::PrepareForSerialization() {
211   List<UnresolvedLocation*> copy(unresolved_locations_.length());
212   copy.AddAll(unresolved_locations_);
213   unresolved_locations_.Clear();
214   for (int i = 0; i < copy.length(); i++) {
215     copy[i]->Resolve();
216     delete copy[i];
217   }
218 }
219 
220 
AllocationEvent(Address addr,int size)221 void AllocationTracker::AllocationEvent(Address addr, int size) {
222   DisallowHeapAllocation no_allocation;
223   Heap* heap = ids_->heap();
224 
225   // Mark the new block as FreeSpace to make sure the heap is iterable
226   // while we are capturing stack trace.
227   heap->CreateFillerObjectAt(addr, size, ClearRecordedSlots::kNo);
228 
229   Isolate* isolate = heap->isolate();
230   int length = 0;
231   JavaScriptFrameIterator it(isolate);
232   while (!it.done() && length < kMaxAllocationTraceLength) {
233     JavaScriptFrame* frame = it.frame();
234     SharedFunctionInfo* shared = frame->function()->shared();
235     SnapshotObjectId id = ids_->FindOrAddEntry(
236         shared->address(), shared->Size(), false);
237     allocation_trace_buffer_[length++] = AddFunctionInfo(shared, id);
238     it.Advance();
239   }
240   if (length == 0) {
241     unsigned index = functionInfoIndexForVMState(isolate->current_vm_state());
242     if (index != 0) {
243       allocation_trace_buffer_[length++] = index;
244     }
245   }
246   AllocationTraceNode* top_node = trace_tree_.AddPathFromEnd(
247       Vector<unsigned>(allocation_trace_buffer_, length));
248   top_node->AddAllocation(size);
249 
250   address_to_trace_.AddRange(addr, size, top_node->id());
251 }
252 
253 
SnapshotObjectIdHash(SnapshotObjectId id)254 static uint32_t SnapshotObjectIdHash(SnapshotObjectId id) {
255   return ComputeIntegerHash(static_cast<uint32_t>(id),
256                             v8::internal::kZeroHashSeed);
257 }
258 
259 
AddFunctionInfo(SharedFunctionInfo * shared,SnapshotObjectId id)260 unsigned AllocationTracker::AddFunctionInfo(SharedFunctionInfo* shared,
261                                             SnapshotObjectId id) {
262   base::HashMap::Entry* entry = id_to_function_info_index_.LookupOrInsert(
263       reinterpret_cast<void*>(id), SnapshotObjectIdHash(id));
264   if (entry->value == NULL) {
265     FunctionInfo* info = new FunctionInfo();
266     info->name = names_->GetFunctionName(shared->DebugName());
267     info->function_id = id;
268     if (shared->script()->IsScript()) {
269       Script* script = Script::cast(shared->script());
270       if (script->name()->IsName()) {
271         Name* name = Name::cast(script->name());
272         info->script_name = names_->GetName(name);
273       }
274       info->script_id = script->id();
275       // Converting start offset into line and column may cause heap
276       // allocations so we postpone them until snapshot serialization.
277       unresolved_locations_.Add(new UnresolvedLocation(
278           script,
279           shared->start_position(),
280           info));
281     }
282     entry->value = reinterpret_cast<void*>(function_info_list_.length());
283     function_info_list_.Add(info);
284   }
285   return static_cast<unsigned>(reinterpret_cast<intptr_t>((entry->value)));
286 }
287 
288 
functionInfoIndexForVMState(StateTag state)289 unsigned AllocationTracker::functionInfoIndexForVMState(StateTag state) {
290   if (state != OTHER) return 0;
291   if (info_index_for_other_state_ == 0) {
292     FunctionInfo* info = new FunctionInfo();
293     info->name = "(V8 API)";
294     info_index_for_other_state_ = function_info_list_.length();
295     function_info_list_.Add(info);
296   }
297   return info_index_for_other_state_;
298 }
299 
300 
UnresolvedLocation(Script * script,int start,FunctionInfo * info)301 AllocationTracker::UnresolvedLocation::UnresolvedLocation(
302     Script* script, int start, FunctionInfo* info)
303     : start_position_(start),
304       info_(info) {
305   script_ = Handle<Script>::cast(
306       script->GetIsolate()->global_handles()->Create(script));
307   GlobalHandles::MakeWeak(reinterpret_cast<Object**>(script_.location()), this,
308                           &HandleWeakScript, v8::WeakCallbackType::kParameter);
309 }
310 
311 
~UnresolvedLocation()312 AllocationTracker::UnresolvedLocation::~UnresolvedLocation() {
313   if (!script_.is_null()) {
314     GlobalHandles::Destroy(reinterpret_cast<Object**>(script_.location()));
315   }
316 }
317 
318 
Resolve()319 void AllocationTracker::UnresolvedLocation::Resolve() {
320   if (script_.is_null()) return;
321   HandleScope scope(script_->GetIsolate());
322   info_->line = Script::GetLineNumber(script_, start_position_);
323   info_->column = Script::GetColumnNumber(script_, start_position_);
324 }
325 
HandleWeakScript(const v8::WeakCallbackInfo<void> & data)326 void AllocationTracker::UnresolvedLocation::HandleWeakScript(
327     const v8::WeakCallbackInfo<void>& data) {
328   UnresolvedLocation* loc =
329       reinterpret_cast<UnresolvedLocation*>(data.GetParameter());
330   GlobalHandles::Destroy(reinterpret_cast<Object**>(loc->script_.location()));
331   loc->script_ = Handle<Script>::null();
332 }
333 
334 
335 }  // namespace internal
336 }  // namespace v8
337