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| 1 // Copyright (c) 2011 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/metrics/stats_table.h" | |
| 6 | |
| 7 #include "base/logging.h" | |
| 8 #include "base/memory/scoped_ptr.h" | |
| 9 #include "base/memory/shared_memory.h" | |
| 10 #include "base/process/process_handle.h" | |
| 11 #include "base/strings/string_piece.h" | |
| 12 #include "base/strings/string_util.h" | |
| 13 #include "base/strings/utf_string_conversions.h" | |
| 14 #include "base/threading/platform_thread.h" | |
| 15 #include "base/threading/thread_local_storage.h" | |
| 16 | |
| 17 namespace base { | |
| 18 | |
| 19 // The StatsTable uses a shared memory segment that is laid out as follows | |
| 20 // | |
| 21 // +-------------------------------------------+ | |
| 22 // | Version | Size | MaxCounters | MaxThreads | | |
| 23 // +-------------------------------------------+ | |
| 24 // | Thread names table | | |
| 25 // +-------------------------------------------+ | |
| 26 // | Thread TID table | | |
| 27 // +-------------------------------------------+ | |
| 28 // | Thread PID table | | |
| 29 // +-------------------------------------------+ | |
| 30 // | Counter names table | | |
| 31 // +-------------------------------------------+ | |
| 32 // | Data | | |
| 33 // +-------------------------------------------+ | |
| 34 // | |
| 35 // The data layout is a grid, where the columns are the thread_ids and the | |
| 36 // rows are the counter_ids. | |
| 37 // | |
| 38 // If the first character of the thread_name is '\0', then that column is | |
| 39 // empty. | |
| 40 // If the first character of the counter_name is '\0', then that row is | |
| 41 // empty. | |
| 42 // | |
| 43 // About Locking: | |
| 44 // This class is designed to be both multi-thread and multi-process safe. | |
| 45 // Aside from initialization, this is done by partitioning the data which | |
| 46 // each thread uses so that no locking is required. However, to allocate | |
| 47 // the rows and columns of the table to particular threads, locking is | |
| 48 // required. | |
| 49 // | |
| 50 // At the shared-memory level, we have a lock. This lock protects the | |
| 51 // shared-memory table only, and is used when we create new counters (e.g. | |
| 52 // use rows) or when we register new threads (e.g. use columns). Reading | |
| 53 // data from the table does not require any locking at the shared memory | |
| 54 // level. | |
| 55 // | |
| 56 // Each process which accesses the table will create a StatsTable object. | |
| 57 // The StatsTable maintains a hash table of the existing counters in the | |
| 58 // table for faster lookup. Since the hash table is process specific, | |
| 59 // each process maintains its own cache. We avoid complexity here by never | |
| 60 // de-allocating from the hash table. (Counters are dynamically added, | |
| 61 // but not dynamically removed). | |
| 62 | |
| 63 // In order for external viewers to be able to read our shared memory, | |
| 64 // we all need to use the same size ints. | |
| 65 COMPILE_ASSERT(sizeof(int)==4, expect_4_byte_ints); | |
| 66 | |
| 67 namespace { | |
| 68 | |
| 69 // An internal version in case we ever change the format of this | |
| 70 // file, and so that we can identify our table. | |
| 71 const int kTableVersion = 0x13131313; | |
| 72 | |
| 73 // The name for un-named counters and threads in the table. | |
| 74 const char kUnknownName[] = "<unknown>"; | |
| 75 | |
| 76 // Calculates delta to align an offset to the size of an int | |
| 77 inline int AlignOffset(int offset) { | |
| 78 return (sizeof(int) - (offset % sizeof(int))) % sizeof(int); | |
| 79 } | |
| 80 | |
| 81 inline int AlignedSize(int size) { | |
| 82 return size + AlignOffset(size); | |
| 83 } | |
| 84 | |
| 85 } // namespace | |
| 86 | |
| 87 // The StatsTable::Internal maintains convenience pointers into the | |
| 88 // shared memory segment. Use this class to keep the data structure | |
| 89 // clean and accessible. | |
| 90 class StatsTable::Internal { | |
| 91 public: | |
| 92 // Various header information contained in the memory mapped segment. | |
| 93 struct TableHeader { | |
| 94 int version; | |
| 95 int size; | |
| 96 int max_counters; | |
| 97 int max_threads; | |
| 98 }; | |
| 99 | |
| 100 // Construct a new Internal based on expected size parameters, or | |
| 101 // return NULL on failure. | |
| 102 static Internal* New(const StatsTable::TableIdentifier& table, | |
| 103 int size, | |
| 104 int max_threads, | |
| 105 int max_counters); | |
| 106 | |
| 107 SharedMemory* shared_memory() { return shared_memory_.get(); } | |
| 108 | |
| 109 // Accessors for our header pointers | |
| 110 TableHeader* table_header() const { return table_header_; } | |
| 111 int version() const { return table_header_->version; } | |
| 112 int size() const { return table_header_->size; } | |
| 113 int max_counters() const { return table_header_->max_counters; } | |
| 114 int max_threads() const { return table_header_->max_threads; } | |
| 115 | |
| 116 // Accessors for our tables | |
| 117 char* thread_name(int slot_id) const { | |
| 118 return &thread_names_table_[ | |
| 119 (slot_id-1) * (StatsTable::kMaxThreadNameLength)]; | |
| 120 } | |
| 121 PlatformThreadId* thread_tid(int slot_id) const { | |
| 122 return &(thread_tid_table_[slot_id-1]); | |
| 123 } | |
| 124 int* thread_pid(int slot_id) const { | |
| 125 return &(thread_pid_table_[slot_id-1]); | |
| 126 } | |
| 127 char* counter_name(int counter_id) const { | |
| 128 return &counter_names_table_[ | |
| 129 (counter_id-1) * (StatsTable::kMaxCounterNameLength)]; | |
| 130 } | |
| 131 int* row(int counter_id) const { | |
| 132 return &data_table_[(counter_id-1) * max_threads()]; | |
| 133 } | |
| 134 | |
| 135 private: | |
| 136 // Constructor is private because you should use New() instead. | |
| 137 explicit Internal(SharedMemory* shared_memory) | |
| 138 : shared_memory_(shared_memory), | |
| 139 table_header_(NULL), | |
| 140 thread_names_table_(NULL), | |
| 141 thread_tid_table_(NULL), | |
| 142 thread_pid_table_(NULL), | |
| 143 counter_names_table_(NULL), | |
| 144 data_table_(NULL) { | |
| 145 } | |
| 146 | |
| 147 // Create or open the SharedMemory used by the stats table. | |
| 148 static SharedMemory* CreateSharedMemory( | |
| 149 const StatsTable::TableIdentifier& table, | |
| 150 int size); | |
| 151 | |
| 152 // Initializes the table on first access. Sets header values | |
| 153 // appropriately and zeroes all counters. | |
| 154 void InitializeTable(void* memory, int size, int max_counters, | |
| 155 int max_threads); | |
| 156 | |
| 157 // Initializes our in-memory pointers into a pre-created StatsTable. | |
| 158 void ComputeMappedPointers(void* memory); | |
| 159 | |
| 160 scoped_ptr<SharedMemory> shared_memory_; | |
| 161 TableHeader* table_header_; | |
| 162 char* thread_names_table_; | |
| 163 PlatformThreadId* thread_tid_table_; | |
| 164 int* thread_pid_table_; | |
| 165 char* counter_names_table_; | |
| 166 int* data_table_; | |
| 167 | |
| 168 DISALLOW_COPY_AND_ASSIGN(Internal); | |
| 169 }; | |
| 170 | |
| 171 // static | |
| 172 StatsTable::Internal* StatsTable::Internal::New( | |
| 173 const StatsTable::TableIdentifier& table, | |
| 174 int size, | |
| 175 int max_threads, | |
| 176 int max_counters) { | |
| 177 scoped_ptr<SharedMemory> shared_memory(CreateSharedMemory(table, size)); | |
| 178 if (!shared_memory.get()) | |
| 179 return NULL; | |
| 180 if (!shared_memory->Map(size)) | |
| 181 return NULL; | |
| 182 void* memory = shared_memory->memory(); | |
| 183 | |
| 184 scoped_ptr<Internal> internal(new Internal(shared_memory.release())); | |
| 185 TableHeader* header = static_cast<TableHeader*>(memory); | |
| 186 | |
| 187 // If the version does not match, then assume the table needs | |
| 188 // to be initialized. | |
| 189 if (header->version != kTableVersion) | |
| 190 internal->InitializeTable(memory, size, max_counters, max_threads); | |
| 191 | |
| 192 // We have a valid table, so compute our pointers. | |
| 193 internal->ComputeMappedPointers(memory); | |
| 194 | |
| 195 return internal.release(); | |
| 196 } | |
| 197 | |
| 198 // static | |
| 199 SharedMemory* StatsTable::Internal::CreateSharedMemory( | |
| 200 const StatsTable::TableIdentifier& table, | |
| 201 int size) { | |
| 202 #if defined(OS_POSIX) | |
| 203 // Check for existing table. | |
| 204 if (table.fd != -1) | |
| 205 return new SharedMemory(table, false); | |
| 206 | |
| 207 // Otherwise we need to create it. | |
| 208 scoped_ptr<SharedMemory> shared_memory(new SharedMemory()); | |
| 209 if (!shared_memory->CreateAnonymous(size)) | |
| 210 return NULL; | |
| 211 return shared_memory.release(); | |
| 212 #elif defined(OS_WIN) | |
| 213 scoped_ptr<SharedMemory> shared_memory(new SharedMemory()); | |
| 214 if (table.empty()) { | |
| 215 // Create an anonymous table. | |
| 216 if (!shared_memory->CreateAnonymous(size)) | |
| 217 return NULL; | |
| 218 } else { | |
| 219 // Create a named table for sharing between processes. | |
| 220 if (!shared_memory->CreateNamedDeprecated(table, true, size)) | |
| 221 return NULL; | |
| 222 } | |
| 223 return shared_memory.release(); | |
| 224 #endif | |
| 225 } | |
| 226 | |
| 227 void StatsTable::Internal::InitializeTable(void* memory, int size, | |
| 228 int max_counters, | |
| 229 int max_threads) { | |
| 230 // Zero everything. | |
| 231 memset(memory, 0, size); | |
| 232 | |
| 233 // Initialize the header. | |
| 234 TableHeader* header = static_cast<TableHeader*>(memory); | |
| 235 header->version = kTableVersion; | |
| 236 header->size = size; | |
| 237 header->max_counters = max_counters; | |
| 238 header->max_threads = max_threads; | |
| 239 } | |
| 240 | |
| 241 void StatsTable::Internal::ComputeMappedPointers(void* memory) { | |
| 242 char* data = static_cast<char*>(memory); | |
| 243 int offset = 0; | |
| 244 | |
| 245 table_header_ = reinterpret_cast<TableHeader*>(data); | |
| 246 offset += sizeof(*table_header_); | |
| 247 offset += AlignOffset(offset); | |
| 248 | |
| 249 // Verify we're looking at a valid StatsTable. | |
| 250 DCHECK_EQ(table_header_->version, kTableVersion); | |
| 251 | |
| 252 thread_names_table_ = reinterpret_cast<char*>(data + offset); | |
| 253 offset += sizeof(char) * | |
| 254 max_threads() * StatsTable::kMaxThreadNameLength; | |
| 255 offset += AlignOffset(offset); | |
| 256 | |
| 257 thread_tid_table_ = reinterpret_cast<PlatformThreadId*>(data + offset); | |
| 258 offset += sizeof(int) * max_threads(); | |
| 259 offset += AlignOffset(offset); | |
| 260 | |
| 261 thread_pid_table_ = reinterpret_cast<int*>(data + offset); | |
| 262 offset += sizeof(int) * max_threads(); | |
| 263 offset += AlignOffset(offset); | |
| 264 | |
| 265 counter_names_table_ = reinterpret_cast<char*>(data + offset); | |
| 266 offset += sizeof(char) * | |
| 267 max_counters() * StatsTable::kMaxCounterNameLength; | |
| 268 offset += AlignOffset(offset); | |
| 269 | |
| 270 data_table_ = reinterpret_cast<int*>(data + offset); | |
| 271 offset += sizeof(int) * max_threads() * max_counters(); | |
| 272 | |
| 273 DCHECK_EQ(offset, size()); | |
| 274 } | |
| 275 | |
| 276 // TLSData carries the data stored in the TLS slots for the | |
| 277 // StatsTable. This is used so that we can properly cleanup when the | |
| 278 // thread exits and return the table slot. | |
| 279 // | |
| 280 // Each thread that calls RegisterThread in the StatsTable will have | |
| 281 // a TLSData stored in its TLS. | |
| 282 struct StatsTable::TLSData { | |
| 283 StatsTable* table; | |
| 284 int slot; | |
| 285 }; | |
| 286 | |
| 287 // We keep a singleton table which can be easily accessed. | |
| 288 StatsTable* global_table = NULL; | |
| 289 | |
| 290 StatsTable::StatsTable(const TableIdentifier& table, | |
| 291 int max_threads, | |
| 292 int max_counters) | |
| 293 : internal_(NULL), | |
| 294 tls_index_(SlotReturnFunction) { | |
| 295 int table_size = | |
| 296 AlignedSize(sizeof(Internal::TableHeader)) + | |
| 297 AlignedSize((max_counters * sizeof(char) * kMaxCounterNameLength)) + | |
| 298 AlignedSize((max_threads * sizeof(char) * kMaxThreadNameLength)) + | |
| 299 AlignedSize(max_threads * sizeof(int)) + | |
| 300 AlignedSize(max_threads * sizeof(int)) + | |
| 301 AlignedSize((sizeof(int) * (max_counters * max_threads))); | |
| 302 | |
| 303 internal_ = Internal::New(table, table_size, max_threads, max_counters); | |
| 304 | |
| 305 if (!internal_) | |
| 306 DPLOG(ERROR) << "StatsTable did not initialize"; | |
| 307 } | |
| 308 | |
| 309 StatsTable::~StatsTable() { | |
| 310 // Before we tear down our copy of the table, be sure to | |
| 311 // unregister our thread. | |
| 312 UnregisterThread(); | |
| 313 | |
| 314 // Return ThreadLocalStorage. At this point, if any registered threads | |
| 315 // still exist, they cannot Unregister. | |
| 316 tls_index_.Free(); | |
| 317 | |
| 318 // Cleanup our shared memory. | |
| 319 delete internal_; | |
| 320 | |
| 321 // If we are the global table, unregister ourselves. | |
| 322 if (global_table == this) | |
| 323 global_table = NULL; | |
| 324 } | |
| 325 | |
| 326 StatsTable* StatsTable::current() { | |
| 327 return global_table; | |
| 328 } | |
| 329 | |
| 330 void StatsTable::set_current(StatsTable* value) { | |
| 331 global_table = value; | |
| 332 } | |
| 333 | |
| 334 int StatsTable::GetSlot() const { | |
| 335 TLSData* data = GetTLSData(); | |
| 336 if (!data) | |
| 337 return 0; | |
| 338 return data->slot; | |
| 339 } | |
| 340 | |
| 341 int StatsTable::RegisterThread(const std::string& name) { | |
| 342 int slot = 0; | |
| 343 if (!internal_) | |
| 344 return 0; | |
| 345 | |
| 346 // Registering a thread requires that we lock the shared memory | |
| 347 // so that two threads don't grab the same slot. Fortunately, | |
| 348 // thread creation shouldn't happen in inner loops. | |
| 349 // TODO(viettrungluu): crbug.com/345734: Use a different locking mechanism. | |
| 350 { | |
| 351 SharedMemoryAutoLockDeprecated lock(internal_->shared_memory()); | |
| 352 slot = FindEmptyThread(); | |
| 353 if (!slot) { | |
| 354 return 0; | |
| 355 } | |
| 356 | |
| 357 // We have space, so consume a column in the table. | |
| 358 std::string thread_name = name; | |
| 359 if (name.empty()) | |
| 360 thread_name = kUnknownName; | |
| 361 strlcpy(internal_->thread_name(slot), thread_name.c_str(), | |
| 362 kMaxThreadNameLength); | |
| 363 *(internal_->thread_tid(slot)) = PlatformThread::CurrentId(); | |
| 364 *(internal_->thread_pid(slot)) = GetCurrentProcId(); | |
| 365 } | |
| 366 | |
| 367 // Set our thread local storage. | |
| 368 TLSData* data = new TLSData; | |
| 369 data->table = this; | |
| 370 data->slot = slot; | |
| 371 tls_index_.Set(data); | |
| 372 return slot; | |
| 373 } | |
| 374 | |
| 375 int StatsTable::CountThreadsRegistered() const { | |
| 376 if (!internal_) | |
| 377 return 0; | |
| 378 | |
| 379 // Loop through the shared memory and count the threads that are active. | |
| 380 // We intentionally do not lock the table during the operation. | |
| 381 int count = 0; | |
| 382 for (int index = 1; index <= internal_->max_threads(); index++) { | |
| 383 char* name = internal_->thread_name(index); | |
| 384 if (*name != '\0') | |
| 385 count++; | |
| 386 } | |
| 387 return count; | |
| 388 } | |
| 389 | |
| 390 int StatsTable::FindCounter(const std::string& name) { | |
| 391 // Note: the API returns counters numbered from 1..N, although | |
| 392 // internally, the array is 0..N-1. This is so that we can return | |
| 393 // zero as "not found". | |
| 394 if (!internal_) | |
| 395 return 0; | |
| 396 | |
| 397 // Create a scope for our auto-lock. | |
| 398 { | |
| 399 AutoLock scoped_lock(counters_lock_); | |
| 400 | |
| 401 // Attempt to find the counter. | |
| 402 CountersMap::const_iterator iter; | |
| 403 iter = counters_.find(name); | |
| 404 if (iter != counters_.end()) | |
| 405 return iter->second; | |
| 406 } | |
| 407 | |
| 408 // Counter does not exist, so add it. | |
| 409 return AddCounter(name); | |
| 410 } | |
| 411 | |
| 412 int* StatsTable::GetLocation(int counter_id, int slot_id) const { | |
| 413 if (!internal_) | |
| 414 return NULL; | |
| 415 if (slot_id > internal_->max_threads()) | |
| 416 return NULL; | |
| 417 | |
| 418 int* row = internal_->row(counter_id); | |
| 419 return &(row[slot_id-1]); | |
| 420 } | |
| 421 | |
| 422 const char* StatsTable::GetRowName(int index) const { | |
| 423 if (!internal_) | |
| 424 return NULL; | |
| 425 | |
| 426 return internal_->counter_name(index); | |
| 427 } | |
| 428 | |
| 429 int StatsTable::GetRowValue(int index) const { | |
| 430 return GetRowValue(index, 0); | |
| 431 } | |
| 432 | |
| 433 int StatsTable::GetRowValue(int index, int pid) const { | |
| 434 if (!internal_) | |
| 435 return 0; | |
| 436 | |
| 437 int rv = 0; | |
| 438 int* row = internal_->row(index); | |
| 439 for (int slot_id = 1; slot_id <= internal_->max_threads(); slot_id++) { | |
| 440 if (pid == 0 || *internal_->thread_pid(slot_id) == pid) | |
| 441 rv += row[slot_id-1]; | |
| 442 } | |
| 443 return rv; | |
| 444 } | |
| 445 | |
| 446 int StatsTable::GetCounterValue(const std::string& name) { | |
| 447 return GetCounterValue(name, 0); | |
| 448 } | |
| 449 | |
| 450 int StatsTable::GetCounterValue(const std::string& name, int pid) { | |
| 451 if (!internal_) | |
| 452 return 0; | |
| 453 | |
| 454 int row = FindCounter(name); | |
| 455 if (!row) | |
| 456 return 0; | |
| 457 return GetRowValue(row, pid); | |
| 458 } | |
| 459 | |
| 460 int StatsTable::GetMaxCounters() const { | |
| 461 if (!internal_) | |
| 462 return 0; | |
| 463 return internal_->max_counters(); | |
| 464 } | |
| 465 | |
| 466 int StatsTable::GetMaxThreads() const { | |
| 467 if (!internal_) | |
| 468 return 0; | |
| 469 return internal_->max_threads(); | |
| 470 } | |
| 471 | |
| 472 int* StatsTable::FindLocation(const char* name) { | |
| 473 // Get the static StatsTable | |
| 474 StatsTable *table = StatsTable::current(); | |
| 475 if (!table) | |
| 476 return NULL; | |
| 477 | |
| 478 // Get the slot for this thread. Try to register | |
| 479 // it if none exists. | |
| 480 int slot = table->GetSlot(); | |
| 481 if (!slot) | |
| 482 slot = table->RegisterThread(std::string()); | |
| 483 if (!slot) | |
| 484 return NULL; | |
| 485 | |
| 486 // Find the counter id for the counter. | |
| 487 std::string str_name(name); | |
| 488 int counter = table->FindCounter(str_name); | |
| 489 | |
| 490 // Now we can find the location in the table. | |
| 491 return table->GetLocation(counter, slot); | |
| 492 } | |
| 493 | |
| 494 void StatsTable::UnregisterThread() { | |
| 495 UnregisterThread(GetTLSData()); | |
| 496 } | |
| 497 | |
| 498 void StatsTable::UnregisterThread(TLSData* data) { | |
| 499 if (!data) | |
| 500 return; | |
| 501 DCHECK(internal_); | |
| 502 | |
| 503 // Mark the slot free by zeroing out the thread name. | |
| 504 char* name = internal_->thread_name(data->slot); | |
| 505 *name = '\0'; | |
| 506 | |
| 507 // Remove the calling thread's TLS so that it cannot use the slot. | |
| 508 tls_index_.Set(NULL); | |
| 509 delete data; | |
| 510 } | |
| 511 | |
| 512 void StatsTable::SlotReturnFunction(void* data) { | |
| 513 // This is called by the TLS destructor, which on some platforms has | |
| 514 // already cleared the TLS info, so use the tls_data argument | |
| 515 // rather than trying to fetch it ourselves. | |
| 516 TLSData* tls_data = static_cast<TLSData*>(data); | |
| 517 if (tls_data) { | |
| 518 DCHECK(tls_data->table); | |
| 519 tls_data->table->UnregisterThread(tls_data); | |
| 520 } | |
| 521 } | |
| 522 | |
| 523 int StatsTable::FindEmptyThread() const { | |
| 524 // Note: the API returns slots numbered from 1..N, although | |
| 525 // internally, the array is 0..N-1. This is so that we can return | |
| 526 // zero as "not found". | |
| 527 // | |
| 528 // The reason for doing this is because the thread 'slot' is stored | |
| 529 // in TLS, which is always initialized to zero, not -1. If 0 were | |
| 530 // returned as a valid slot number, it would be confused with the | |
| 531 // uninitialized state. | |
| 532 if (!internal_) | |
| 533 return 0; | |
| 534 | |
| 535 int index = 1; | |
| 536 for (; index <= internal_->max_threads(); index++) { | |
| 537 char* name = internal_->thread_name(index); | |
| 538 if (!*name) | |
| 539 break; | |
| 540 } | |
| 541 if (index > internal_->max_threads()) | |
| 542 return 0; // The table is full. | |
| 543 return index; | |
| 544 } | |
| 545 | |
| 546 int StatsTable::FindCounterOrEmptyRow(const std::string& name) const { | |
| 547 // Note: the API returns slots numbered from 1..N, although | |
| 548 // internally, the array is 0..N-1. This is so that we can return | |
| 549 // zero as "not found". | |
| 550 // | |
| 551 // There isn't much reason for this other than to be consistent | |
| 552 // with the way we track columns for thread slots. (See comments | |
| 553 // in FindEmptyThread for why it is done this way). | |
| 554 if (!internal_) | |
| 555 return 0; | |
| 556 | |
| 557 int free_slot = 0; | |
| 558 for (int index = 1; index <= internal_->max_counters(); index++) { | |
| 559 char* row_name = internal_->counter_name(index); | |
| 560 if (!*row_name && !free_slot) | |
| 561 free_slot = index; // save that we found a free slot | |
| 562 else if (!strncmp(row_name, name.c_str(), kMaxCounterNameLength)) | |
| 563 return index; | |
| 564 } | |
| 565 return free_slot; | |
| 566 } | |
| 567 | |
| 568 int StatsTable::AddCounter(const std::string& name) { | |
| 569 if (!internal_) | |
| 570 return 0; | |
| 571 | |
| 572 int counter_id = 0; | |
| 573 { | |
| 574 // To add a counter to the shared memory, we need the | |
| 575 // shared memory lock. | |
| 576 SharedMemoryAutoLockDeprecated lock(internal_->shared_memory()); | |
| 577 | |
| 578 // We have space, so create a new counter. | |
| 579 counter_id = FindCounterOrEmptyRow(name); | |
| 580 if (!counter_id) | |
| 581 return 0; | |
| 582 | |
| 583 std::string counter_name = name; | |
| 584 if (name.empty()) | |
| 585 counter_name = kUnknownName; | |
| 586 strlcpy(internal_->counter_name(counter_id), counter_name.c_str(), | |
| 587 kMaxCounterNameLength); | |
| 588 } | |
| 589 | |
| 590 // now add to our in-memory cache | |
| 591 { | |
| 592 AutoLock lock(counters_lock_); | |
| 593 counters_[name] = counter_id; | |
| 594 } | |
| 595 return counter_id; | |
| 596 } | |
| 597 | |
| 598 StatsTable::TLSData* StatsTable::GetTLSData() const { | |
| 599 TLSData* data = | |
| 600 static_cast<TLSData*>(tls_index_.Get()); | |
| 601 if (!data) | |
| 602 return NULL; | |
| 603 | |
| 604 DCHECK(data->slot); | |
| 605 DCHECK_EQ(data->table, this); | |
| 606 return data; | |
| 607 } | |
| 608 | |
| 609 #if defined(OS_POSIX) | |
| 610 SharedMemoryHandle StatsTable::GetSharedMemoryHandle() const { | |
| 611 if (!internal_) | |
| 612 return SharedMemory::NULLHandle(); | |
| 613 return internal_->shared_memory()->handle(); | |
| 614 } | |
| 615 #endif | |
| 616 | |
| 617 } // namespace base | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 935333002:
Update from https://crrev.com/316786 (Closed)
Base URL: git@github.com:domokit/mojo.git@master