| OLD | NEW |
|---|
| (Empty) |
| 1 // Copyright 2013 The Chromium 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 "base/trace_event/trace_event_memory.h" | |
| 6 | |
| 7 #include "base/debug/leak_annotations.h" | |
| 8 #include "base/lazy_instance.h" | |
| 9 #include "base/location.h" | |
| 10 #include "base/logging.h" | |
| 11 #include "base/memory/scoped_ptr.h" | |
| 12 #include "base/single_thread_task_runner.h" | |
| 13 #include "base/strings/string_number_conversions.h" | |
| 14 #include "base/strings/string_split.h" | |
| 15 #include "base/strings/string_util.h" | |
| 16 #include "base/threading/thread_local_storage.h" | |
| 17 #include "base/trace_event/trace_event.h" | |
| 18 | |
| 19 namespace base { | |
| 20 namespace trace_event { | |
| 21 | |
| 22 namespace { | |
| 23 | |
| 24 // Maximum number of nested TRACE_EVENT scopes to record. Must be less than | |
| 25 // or equal to HeapProfileTable::kMaxStackDepth / 2 because we record two | |
| 26 // entries on the pseudo-stack per scope. | |
| 27 const size_t kMaxScopeDepth = 16; | |
| 28 | |
| 29 ///////////////////////////////////////////////////////////////////////////// | |
| 30 // Holds a memory dump until the tracing system needs to serialize it. | |
| 31 class MemoryDumpHolder : public base::trace_event::ConvertableToTraceFormat { | |
| 32 public: | |
| 33 // Takes ownership of dump, which must be a JSON string, allocated with | |
| 34 // malloc() and NULL terminated. | |
| 35 explicit MemoryDumpHolder(char* dump) : dump_(dump) {} | |
| 36 | |
| 37 // base::trace_event::ConvertableToTraceFormat overrides: | |
| 38 void AppendAsTraceFormat(std::string* out) const override { | |
| 39 AppendHeapProfileAsTraceFormat(dump_, out); | |
| 40 } | |
| 41 | |
| 42 private: | |
| 43 ~MemoryDumpHolder() override { free(dump_); } | |
| 44 | |
| 45 char* dump_; | |
| 46 | |
| 47 DISALLOW_COPY_AND_ASSIGN(MemoryDumpHolder); | |
| 48 }; | |
| 49 | |
| 50 ///////////////////////////////////////////////////////////////////////////// | |
| 51 // Records a stack of TRACE_MEMORY events. One per thread is required. | |
| 52 struct TraceMemoryStack { | |
| 53 TraceMemoryStack() : scope_depth(0) { | |
| 54 memset(scope_data, 0, kMaxScopeDepth * sizeof(scope_data[0])); | |
| 55 } | |
| 56 | |
| 57 // Depth of the currently nested TRACE_EVENT scopes. Allowed to be greater | |
| 58 // than kMaxScopeDepth so we can match scope pushes and pops even if we don't | |
| 59 // have enough space to store the EventData. | |
| 60 size_t scope_depth; | |
| 61 | |
| 62 // Stack of categories and names. | |
| 63 ScopedTraceMemory::ScopeData scope_data[kMaxScopeDepth]; | |
| 64 }; | |
| 65 | |
| 66 // Pointer to a TraceMemoryStack per thread. | |
| 67 base::ThreadLocalStorage::StaticSlot tls_trace_memory_stack = TLS_INITIALIZER; | |
| 68 | |
| 69 // Clean up memory pointed to by our thread-local storage. | |
| 70 void DeleteStackOnThreadCleanup(void* value) { | |
| 71 TraceMemoryStack* stack = static_cast<TraceMemoryStack*>(value); | |
| 72 delete stack; | |
| 73 } | |
| 74 | |
| 75 // Initializes the thread-local TraceMemoryStack pointer. | |
| 76 void InitThreadLocalStorage() { | |
| 77 if (tls_trace_memory_stack.initialized()) | |
| 78 return; | |
| 79 // Initialize the thread-local storage key. | |
| 80 tls_trace_memory_stack.Initialize(&DeleteStackOnThreadCleanup); | |
| 81 } | |
| 82 | |
| 83 // Clean up thread-local-storage in the main thread. | |
| 84 void CleanupThreadLocalStorage() { | |
| 85 if (!tls_trace_memory_stack.initialized()) | |
| 86 return; | |
| 87 TraceMemoryStack* stack = | |
| 88 static_cast<TraceMemoryStack*>(tls_trace_memory_stack.Get()); | |
| 89 delete stack; | |
| 90 tls_trace_memory_stack.Set(NULL); | |
| 91 // Intentionally do not release the thread-local-storage key here, that is, | |
| 92 // do not call tls_trace_memory_stack.Free(). Other threads have lazily | |
| 93 // created pointers in thread-local-storage via GetTraceMemoryStack() below. | |
| 94 // Those threads need to run the DeleteStack() destructor function when they | |
| 95 // exit. If we release the key the destructor will not be called and those | |
| 96 // threads will not clean up their memory. | |
| 97 } | |
| 98 | |
| 99 // Returns the thread-local trace memory stack for the current thread, creating | |
| 100 // one if needed. Returns NULL if the thread-local storage key isn't | |
| 101 // initialized, which indicates that heap profiling isn't running. | |
| 102 TraceMemoryStack* GetTraceMemoryStack() { | |
| 103 TraceMemoryStack* stack = | |
| 104 static_cast<TraceMemoryStack*>(tls_trace_memory_stack.Get()); | |
| 105 // Lazily initialize TraceMemoryStack objects for new threads. | |
| 106 if (!stack) { | |
| 107 stack = new TraceMemoryStack; | |
| 108 tls_trace_memory_stack.Set(stack); | |
| 109 } | |
| 110 return stack; | |
| 111 } | |
| 112 | |
| 113 // Returns a "pseudo-stack" of pointers to trace event categories and names. | |
| 114 // Because tcmalloc stores one pointer per stack frame this converts N nested | |
| 115 // trace events into N * 2 pseudo-stack entries. Thus this macro invocation: | |
| 116 // TRACE_EVENT0("category1", "name1"); | |
| 117 // TRACE_EVENT0("category2", "name2"); | |
| 118 // becomes this pseudo-stack: | |
| 119 // stack_out[0] = "category1" | |
| 120 // stack_out[1] = "name1" | |
| 121 // stack_out[2] = "category2" | |
| 122 // stack_out[3] = "name2" | |
| 123 // Returns int instead of size_t to match the signature required by tcmalloc. | |
| 124 int GetPseudoStack(int skip_count_ignored, void** stack_out) { | |
| 125 // If the tracing system isn't fully initialized, just skip this allocation. | |
| 126 // Attempting to initialize will allocate memory, causing this function to | |
| 127 // be called recursively from inside the allocator. | |
| 128 if (!tls_trace_memory_stack.initialized() || !tls_trace_memory_stack.Get()) | |
| 129 return 0; | |
| 130 TraceMemoryStack* stack = | |
| 131 static_cast<TraceMemoryStack*>(tls_trace_memory_stack.Get()); | |
| 132 // Copy at most kMaxScopeDepth scope entries. | |
| 133 const size_t count = std::min(stack->scope_depth, kMaxScopeDepth); | |
| 134 // Notes that memcpy() works for zero bytes. | |
| 135 memcpy(stack_out, | |
| 136 stack->scope_data, | |
| 137 count * sizeof(stack->scope_data[0])); | |
| 138 // Each item in the trace event stack contains both name and category so tell | |
| 139 // tcmalloc that we have returned |count| * 2 stack frames. | |
| 140 return static_cast<int>(count * 2); | |
| 141 } | |
| 142 | |
| 143 } // namespace | |
| 144 | |
| 145 ////////////////////////////////////////////////////////////////////////////// | |
| 146 | |
| 147 TraceMemoryController::TraceMemoryController( | |
| 148 scoped_refptr<SingleThreadTaskRunner> task_runner, | |
| 149 HeapProfilerStartFunction heap_profiler_start_function, | |
| 150 HeapProfilerStopFunction heap_profiler_stop_function, | |
| 151 GetHeapProfileFunction get_heap_profile_function) | |
| 152 : task_runner_(task_runner.Pass()), | |
| 153 heap_profiler_start_function_(heap_profiler_start_function), | |
| 154 heap_profiler_stop_function_(heap_profiler_stop_function), | |
| 155 get_heap_profile_function_(get_heap_profile_function), | |
| 156 weak_factory_(this) { | |
| 157 // Force the "memory" category to show up in the trace viewer. | |
| 158 TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("memory"), "init"); | |
| 159 // Watch for the tracing system being enabled. | |
| 160 TraceLog::GetInstance()->AddEnabledStateObserver(this); | |
| 161 } | |
| 162 | |
| 163 TraceMemoryController::~TraceMemoryController() { | |
| 164 if (dump_timer_.IsRunning()) | |
| 165 StopProfiling(); | |
| 166 TraceLog::GetInstance()->RemoveEnabledStateObserver(this); | |
| 167 } | |
| 168 | |
| 169 // base::trace_event::TraceLog::EnabledStateChangedObserver overrides: | |
| 170 void TraceMemoryController::OnTraceLogEnabled() { | |
| 171 // Check to see if tracing is enabled for the memory category. | |
| 172 bool enabled; | |
| 173 TRACE_EVENT_CATEGORY_GROUP_ENABLED(TRACE_DISABLED_BY_DEFAULT("memory"), | |
| 174 &enabled); | |
| 175 if (!enabled) | |
| 176 return; | |
| 177 DVLOG(1) << "OnTraceLogEnabled"; | |
| 178 task_runner_->PostTask(FROM_HERE, | |
| 179 base::Bind(&TraceMemoryController::StartProfiling, | |
| 180 weak_factory_.GetWeakPtr())); | |
| 181 } | |
| 182 | |
| 183 void TraceMemoryController::OnTraceLogDisabled() { | |
| 184 // The memory category is always disabled before OnTraceLogDisabled() is | |
| 185 // called, so we cannot tell if it was enabled before. Always try to turn | |
| 186 // off profiling. | |
| 187 DVLOG(1) << "OnTraceLogDisabled"; | |
| 188 task_runner_->PostTask(FROM_HERE, | |
| 189 base::Bind(&TraceMemoryController::StopProfiling, | |
| 190 weak_factory_.GetWeakPtr())); | |
| 191 } | |
| 192 | |
| 193 void TraceMemoryController::StartProfiling() { | |
| 194 // Watch for the tracing framework sending enabling more than once. | |
| 195 if (dump_timer_.IsRunning()) | |
| 196 return; | |
| 197 DVLOG(1) << "Starting trace memory"; | |
| 198 InitThreadLocalStorage(); | |
| 199 ScopedTraceMemory::set_enabled(true); | |
| 200 // Call ::HeapProfilerWithPseudoStackStart(). | |
| 201 heap_profiler_start_function_(&GetPseudoStack); | |
| 202 const int kDumpIntervalSeconds = 5; | |
| 203 dump_timer_.Start(FROM_HERE, | |
| 204 TimeDelta::FromSeconds(kDumpIntervalSeconds), | |
| 205 base::Bind(&TraceMemoryController::DumpMemoryProfile, | |
| 206 weak_factory_.GetWeakPtr())); | |
| 207 } | |
| 208 | |
| 209 void TraceMemoryController::DumpMemoryProfile() { | |
| 210 // Don't trace allocations here in the memory tracing system. | |
| 211 INTERNAL_TRACE_MEMORY(TRACE_DISABLED_BY_DEFAULT("memory"), | |
| 212 TRACE_MEMORY_IGNORE); | |
| 213 | |
| 214 DVLOG(1) << "DumpMemoryProfile"; | |
| 215 // MemoryDumpHolder takes ownership of this string. See GetHeapProfile() in | |
| 216 // tcmalloc for details. | |
| 217 char* dump = get_heap_profile_function_(); | |
| 218 const int kSnapshotId = 1; | |
| 219 TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID( | |
| 220 TRACE_DISABLED_BY_DEFAULT("memory"), | |
| 221 "memory::Heap", | |
| 222 kSnapshotId, | |
| 223 scoped_refptr<ConvertableToTraceFormat>(new MemoryDumpHolder(dump))); | |
| 224 } | |
| 225 | |
| 226 void TraceMemoryController::StopProfiling() { | |
| 227 // Watch for the tracing framework sending disabled more than once. | |
| 228 if (!dump_timer_.IsRunning()) | |
| 229 return; | |
| 230 DVLOG(1) << "Stopping trace memory"; | |
| 231 dump_timer_.Stop(); | |
| 232 ScopedTraceMemory::set_enabled(false); | |
| 233 CleanupThreadLocalStorage(); | |
| 234 // Call ::HeapProfilerStop(). | |
| 235 heap_profiler_stop_function_(); | |
| 236 } | |
| 237 | |
| 238 bool TraceMemoryController::IsTimerRunningForTest() const { | |
| 239 return dump_timer_.IsRunning(); | |
| 240 } | |
| 241 | |
| 242 ///////////////////////////////////////////////////////////////////////////// | |
| 243 | |
| 244 // static | |
| 245 bool ScopedTraceMemory::enabled_ = false; | |
| 246 | |
| 247 void ScopedTraceMemory::Initialize(const char* category, const char* name) { | |
| 248 DCHECK(enabled_); | |
| 249 // Get our thread's copy of the stack. | |
| 250 TraceMemoryStack* trace_memory_stack = GetTraceMemoryStack(); | |
| 251 const size_t index = trace_memory_stack->scope_depth; | |
| 252 // Don't record data for deeply nested scopes, but continue to increment | |
| 253 // |stack_depth| so we can match pushes and pops. | |
| 254 if (index < kMaxScopeDepth) { | |
| 255 ScopeData& event = trace_memory_stack->scope_data[index]; | |
| 256 event.category = category; | |
| 257 event.name = name; | |
| 258 } | |
| 259 trace_memory_stack->scope_depth++; | |
| 260 } | |
| 261 | |
| 262 void ScopedTraceMemory::Destroy() { | |
| 263 DCHECK(enabled_); | |
| 264 // Get our thread's copy of the stack. | |
| 265 TraceMemoryStack* trace_memory_stack = GetTraceMemoryStack(); | |
| 266 // The tracing system can be turned on with ScopedTraceMemory objects | |
| 267 // allocated on the stack, so avoid potential underflow as they are destroyed. | |
| 268 if (trace_memory_stack->scope_depth > 0) | |
| 269 trace_memory_stack->scope_depth--; | |
| 270 } | |
| 271 | |
| 272 // static | |
| 273 void ScopedTraceMemory::InitForTest() { | |
| 274 InitThreadLocalStorage(); | |
| 275 enabled_ = true; | |
| 276 } | |
| 277 | |
| 278 // static | |
| 279 void ScopedTraceMemory::CleanupForTest() { | |
| 280 enabled_ = false; | |
| 281 CleanupThreadLocalStorage(); | |
| 282 } | |
| 283 | |
| 284 // static | |
| 285 int ScopedTraceMemory::GetStackDepthForTest() { | |
| 286 TraceMemoryStack* stack = GetTraceMemoryStack(); | |
| 287 return static_cast<int>(stack->scope_depth); | |
| 288 } | |
| 289 | |
| 290 // static | |
| 291 ScopedTraceMemory::ScopeData ScopedTraceMemory::GetScopeDataForTest( | |
| 292 int stack_index) { | |
| 293 TraceMemoryStack* stack = GetTraceMemoryStack(); | |
| 294 return stack->scope_data[stack_index]; | |
| 295 } | |
| 296 | |
| 297 ///////////////////////////////////////////////////////////////////////////// | |
| 298 | |
| 299 void AppendHeapProfileAsTraceFormat(const char* input, std::string* output) { | |
| 300 // Heap profile output has a header total line, then a list of stacks with | |
| 301 // memory totals, like this: | |
| 302 // | |
| 303 // heap profile: 357: 55227 [ 14653: 2624014] @ heapprofile | |
| 304 // 95: 40940 [ 649: 114260] @ 0x7fa7f4b3be13 | |
| 305 // 77: 32546 [ 742: 106234] @ | |
| 306 // 68: 4195 [ 1087: 98009] @ 0x7fa7fa9b9ba0 0x7fa7f4b3be13 | |
| 307 // | |
| 308 // MAPPED_LIBRARIES: | |
| 309 // 1be411fc1000-1be4139e4000 rw-p 00000000 00:00 0 | |
| 310 // 1be4139e4000-1be4139e5000 ---p 00000000 00:00 0 | |
| 311 // ... | |
| 312 // | |
| 313 // Skip input after MAPPED_LIBRARIES. | |
| 314 std::string input_string; | |
| 315 const char* mapped_libraries = strstr(input, "MAPPED_LIBRARIES"); | |
| 316 if (mapped_libraries) { | |
| 317 input_string.assign(input, mapped_libraries - input); | |
| 318 } else { | |
| 319 input_string.assign(input); | |
| 320 } | |
| 321 | |
| 322 std::vector<std::string> lines = base::SplitString( | |
| 323 input_string, "\n", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY); | |
| 324 if (lines.empty()) { | |
| 325 DLOG(WARNING) << "No lines found"; | |
| 326 return; | |
| 327 } | |
| 328 | |
| 329 // Handle the initial summary line. | |
| 330 output->append("["); | |
| 331 AppendHeapProfileTotalsAsTraceFormat(lines[0], output); | |
| 332 | |
| 333 // Handle the following stack trace lines. | |
| 334 for (size_t i = 1; i < lines.size(); i++) | |
| 335 AppendHeapProfileLineAsTraceFormat(lines[i], output); | |
| 336 output->append("]\n"); | |
| 337 } | |
| 338 | |
| 339 void AppendHeapProfileTotalsAsTraceFormat(const std::string& line, | |
| 340 std::string* output) { | |
| 341 // This is what a line looks like: | |
| 342 // heap profile: 357: 55227 [ 14653: 2624014] @ heapprofile | |
| 343 // | |
| 344 // The numbers represent total allocations since profiling was enabled. | |
| 345 // From the example above: | |
| 346 // 357 = Outstanding allocations (mallocs - frees) | |
| 347 // 55227 = Outstanding bytes (malloc bytes - free bytes) | |
| 348 // 14653 = Total allocations (mallocs) | |
| 349 // 2624014 = Total bytes (malloc bytes) | |
| 350 std::vector<std::string> tokens = base::SplitString( | |
| 351 line, " :[]@", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY); | |
| 352 if (tokens.size() < 4) { | |
| 353 DLOG(WARNING) << "Invalid totals line " << line; | |
| 354 return; | |
| 355 } | |
| 356 DCHECK_EQ(tokens[0], "heap"); | |
| 357 DCHECK_EQ(tokens[1], "profile"); | |
| 358 output->append("{\"current_allocs\": "); | |
| 359 output->append(tokens[2]); | |
| 360 output->append(", \"current_bytes\": "); | |
| 361 output->append(tokens[3]); | |
| 362 output->append(", \"trace\": \"\"}"); | |
| 363 } | |
| 364 | |
| 365 bool AppendHeapProfileLineAsTraceFormat(const std::string& line, | |
| 366 std::string* output) { | |
| 367 // This is what a line looks like: | |
| 368 // 68: 4195 [ 1087: 98009] @ 0x7fa7fa9b9ba0 0x7fa7f4b3be13 | |
| 369 // | |
| 370 // The numbers represent allocations for a particular stack trace since | |
| 371 // profiling was enabled. From the example above: | |
| 372 // 68 = Outstanding allocations (mallocs - frees) | |
| 373 // 4195 = Outstanding bytes (malloc bytes - free bytes) | |
| 374 // 1087 = Total allocations (mallocs) | |
| 375 // 98009 = Total bytes (malloc bytes) | |
| 376 // | |
| 377 // 0x7fa7fa9b9ba0 0x7fa7f4b3be13 = Stack trace represented as pointers to | |
| 378 // static strings from trace event categories | |
| 379 // and names. | |
| 380 std::vector<std::string> tokens = base::SplitString( | |
| 381 line, " :[]@", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY); | |
| 382 // It's valid to have no stack addresses, so only require 4 tokens. | |
| 383 if (tokens.size() < 4) { | |
| 384 DLOG(WARNING) << "Invalid line " << line; | |
| 385 return false; | |
| 386 } | |
| 387 // Don't bother with stacks that have no current allocations. | |
| 388 if (tokens[0] == "0") | |
| 389 return false; | |
| 390 output->append(",\n"); | |
| 391 output->append("{\"current_allocs\": "); | |
| 392 output->append(tokens[0]); | |
| 393 output->append(", \"current_bytes\": "); | |
| 394 output->append(tokens[1]); | |
| 395 output->append(", \"trace\": \""); | |
| 396 | |
| 397 // Convert pairs of "stack addresses" into category and name strings. | |
| 398 const std::string kSingleQuote = "'"; | |
| 399 for (size_t t = 4; t < tokens.size(); t += 2) { | |
| 400 // Casting strings into pointers is ugly but otherwise tcmalloc would need | |
| 401 // to gain a special output serializer just for pseudo-stacks. | |
| 402 const char* trace_category = StringFromHexAddress(tokens[t]); | |
| 403 DCHECK_LT(t + 1, tokens.size()); | |
| 404 const char* trace_name = StringFromHexAddress(tokens[t + 1]); | |
| 405 | |
| 406 // TODO(jamescook): Report the trace category and name separately to the | |
| 407 // trace viewer and allow it to decide what decorations to apply. For now | |
| 408 // just hard-code a decoration for posted tasks (toplevel). | |
| 409 std::string trace_string(trace_name); | |
| 410 if (!strcmp(trace_category, "toplevel")) | |
| 411 trace_string.append("->PostTask"); | |
| 412 | |
| 413 // Some trace name strings have double quotes, convert them to single. | |
| 414 ReplaceChars(trace_string, "\"", kSingleQuote, &trace_string); | |
| 415 | |
| 416 output->append(trace_string); | |
| 417 | |
| 418 // Trace viewer expects a trailing space. | |
| 419 output->append(" "); | |
| 420 } | |
| 421 output->append("\"}"); | |
| 422 return true; | |
| 423 } | |
| 424 | |
| 425 const char* StringFromHexAddress(const std::string& hex_address) { | |
| 426 uint64 address = 0; | |
| 427 if (!base::HexStringToUInt64(hex_address, &address)) | |
| 428 return "error"; | |
| 429 if (!address) | |
| 430 return "null"; | |
| 431 // Note that this cast handles 64-bit to 32-bit conversion if necessary. | |
| 432 return reinterpret_cast<const char*>(address); | |
| 433 } | |
| 434 | |
| 435 } // namespace trace_event | |
| 436 } // namespace base | |
| OLD | NEW |
|---|
Chromium Code Reviews
