1 /* 2 * Copyright 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "jit_code_cache.h" 18 19 #include <sstream> 20 21 #include "art_method-inl.h" 22 #include "base/enums.h" 23 #include "base/stl_util.h" 24 #include "base/systrace.h" 25 #include "base/time_utils.h" 26 #include "cha.h" 27 #include "debugger_interface.h" 28 #include "entrypoints/runtime_asm_entrypoints.h" 29 #include "gc/accounting/bitmap-inl.h" 30 #include "gc/scoped_gc_critical_section.h" 31 #include "jit/jit.h" 32 #include "jit/profiling_info.h" 33 #include "linear_alloc.h" 34 #include "mem_map.h" 35 #include "oat_file-inl.h" 36 #include "scoped_thread_state_change-inl.h" 37 #include "thread_list.h" 38 39 namespace art { 40 namespace jit { 41 42 static constexpr int kProtAll = PROT_READ | PROT_WRITE | PROT_EXEC; 43 static constexpr int kProtData = PROT_READ | PROT_WRITE; 44 static constexpr int kProtCode = PROT_READ | PROT_EXEC; 45 46 static constexpr size_t kCodeSizeLogThreshold = 50 * KB; 47 static constexpr size_t kStackMapSizeLogThreshold = 50 * KB; 48 49 #define CHECKED_MPROTECT(memory, size, prot) \ 50 do { \ 51 int rc = mprotect(memory, size, prot); \ 52 if (UNLIKELY(rc != 0)) { \ 53 errno = rc; \ 54 PLOG(FATAL) << "Failed to mprotect jit code cache"; \ 55 } \ 56 } while (false) \ 57 58 JitCodeCache* JitCodeCache::Create(size_t initial_capacity, 59 size_t max_capacity, 60 bool generate_debug_info, 61 std::string* error_msg) { 62 ScopedTrace trace(__PRETTY_FUNCTION__); 63 CHECK_GE(max_capacity, initial_capacity); 64 65 // Generating debug information is mostly for using the 'perf' tool, which does 66 // not work with ashmem. 67 bool use_ashmem = !generate_debug_info; 68 // With 'perf', we want a 1-1 mapping between an address and a method. 69 bool garbage_collect_code = !generate_debug_info; 70 71 // We need to have 32 bit offsets from method headers in code cache which point to things 72 // in the data cache. If the maps are more than 4G apart, having multiple maps wouldn't work. 73 // Ensure we're below 1 GB to be safe. 74 if (max_capacity > 1 * GB) { 75 std::ostringstream oss; 76 oss << "Maxium code cache capacity is limited to 1 GB, " 77 << PrettySize(max_capacity) << " is too big"; 78 *error_msg = oss.str(); 79 return nullptr; 80 } 81 82 std::string error_str; 83 // Map name specific for android_os_Debug.cpp accounting. 84 // Map in low 4gb to simplify accessing root tables for x86_64. 85 // We could do PC-relative addressing to avoid this problem, but that 86 // would require reserving code and data area before submitting, which 87 // means more windows for the code memory to be RWX. 88 MemMap* data_map = MemMap::MapAnonymous( 89 "data-code-cache", nullptr, 90 max_capacity, 91 kProtAll, 92 /* low_4gb */ true, 93 /* reuse */ false, 94 &error_str, 95 use_ashmem); 96 if (data_map == nullptr) { 97 std::ostringstream oss; 98 oss << "Failed to create read write execute cache: " << error_str << " size=" << max_capacity; 99 *error_msg = oss.str(); 100 return nullptr; 101 } 102 103 // Align both capacities to page size, as that's the unit mspaces use. 104 initial_capacity = RoundDown(initial_capacity, 2 * kPageSize); 105 max_capacity = RoundDown(max_capacity, 2 * kPageSize); 106 107 // Data cache is 1 / 2 of the map. 108 // TODO: Make this variable? 109 size_t data_size = max_capacity / 2; 110 size_t code_size = max_capacity - data_size; 111 DCHECK_EQ(code_size + data_size, max_capacity); 112 uint8_t* divider = data_map->Begin() + data_size; 113 114 MemMap* code_map = 115 data_map->RemapAtEnd(divider, "jit-code-cache", kProtAll, &error_str, use_ashmem); 116 if (code_map == nullptr) { 117 std::ostringstream oss; 118 oss << "Failed to create read write execute cache: " << error_str << " size=" << max_capacity; 119 *error_msg = oss.str(); 120 return nullptr; 121 } 122 DCHECK_EQ(code_map->Begin(), divider); 123 data_size = initial_capacity / 2; 124 code_size = initial_capacity - data_size; 125 DCHECK_EQ(code_size + data_size, initial_capacity); 126 return new JitCodeCache( 127 code_map, data_map, code_size, data_size, max_capacity, garbage_collect_code); 128 } 129 130 JitCodeCache::JitCodeCache(MemMap* code_map, 131 MemMap* data_map, 132 size_t initial_code_capacity, 133 size_t initial_data_capacity, 134 size_t max_capacity, 135 bool garbage_collect_code) 136 : lock_("Jit code cache", kJitCodeCacheLock), 137 lock_cond_("Jit code cache condition variable", lock_), 138 collection_in_progress_(false), 139 code_map_(code_map), 140 data_map_(data_map), 141 max_capacity_(max_capacity), 142 current_capacity_(initial_code_capacity + initial_data_capacity), 143 code_end_(initial_code_capacity), 144 data_end_(initial_data_capacity), 145 last_collection_increased_code_cache_(false), 146 last_update_time_ns_(0), 147 garbage_collect_code_(garbage_collect_code), 148 used_memory_for_data_(0), 149 used_memory_for_code_(0), 150 number_of_compilations_(0), 151 number_of_osr_compilations_(0), 152 number_of_collections_(0), 153 histogram_stack_map_memory_use_("Memory used for stack maps", 16), 154 histogram_code_memory_use_("Memory used for compiled code", 16), 155 histogram_profiling_info_memory_use_("Memory used for profiling info", 16), 156 is_weak_access_enabled_(true), 157 inline_cache_cond_("Jit inline cache condition variable", lock_) { 158 159 DCHECK_GE(max_capacity, initial_code_capacity + initial_data_capacity); 160 code_mspace_ = create_mspace_with_base(code_map_->Begin(), code_end_, false /*locked*/); 161 data_mspace_ = create_mspace_with_base(data_map_->Begin(), data_end_, false /*locked*/); 162 163 if (code_mspace_ == nullptr || data_mspace_ == nullptr) { 164 PLOG(FATAL) << "create_mspace_with_base failed"; 165 } 166 167 SetFootprintLimit(current_capacity_); 168 169 CHECKED_MPROTECT(code_map_->Begin(), code_map_->Size(), kProtCode); 170 CHECKED_MPROTECT(data_map_->Begin(), data_map_->Size(), kProtData); 171 172 VLOG(jit) << "Created jit code cache: initial data size=" 173 << PrettySize(initial_data_capacity) 174 << ", initial code size=" 175 << PrettySize(initial_code_capacity); 176 } 177 178 bool JitCodeCache::ContainsPc(const void* ptr) const { 179 return code_map_->Begin() <= ptr && ptr < code_map_->End(); 180 } 181 182 bool JitCodeCache::ContainsMethod(ArtMethod* method) { 183 MutexLock mu(Thread::Current(), lock_); 184 for (auto& it : method_code_map_) { 185 if (it.second == method) { 186 return true; 187 } 188 } 189 return false; 190 } 191 192 class ScopedCodeCacheWrite : ScopedTrace { 193 public: 194 explicit ScopedCodeCacheWrite(MemMap* code_map, bool only_for_tlb_shootdown = false) 195 : ScopedTrace("ScopedCodeCacheWrite"), 196 code_map_(code_map), 197 only_for_tlb_shootdown_(only_for_tlb_shootdown) { 198 ScopedTrace trace("mprotect all"); 199 CHECKED_MPROTECT( 200 code_map_->Begin(), only_for_tlb_shootdown_ ? kPageSize : code_map_->Size(), kProtAll); 201 } 202 ~ScopedCodeCacheWrite() { 203 ScopedTrace trace("mprotect code"); 204 CHECKED_MPROTECT( 205 code_map_->Begin(), only_for_tlb_shootdown_ ? kPageSize : code_map_->Size(), kProtCode); 206 } 207 private: 208 MemMap* const code_map_; 209 210 // If we're using ScopedCacheWrite only for TLB shootdown, we limit the scope of mprotect to 211 // one page. 212 const bool only_for_tlb_shootdown_; 213 214 DISALLOW_COPY_AND_ASSIGN(ScopedCodeCacheWrite); 215 }; 216 217 uint8_t* JitCodeCache::CommitCode(Thread* self, 218 ArtMethod* method, 219 uint8_t* stack_map, 220 uint8_t* method_info, 221 uint8_t* roots_data, 222 size_t frame_size_in_bytes, 223 size_t core_spill_mask, 224 size_t fp_spill_mask, 225 const uint8_t* code, 226 size_t code_size, 227 size_t data_size, 228 bool osr, 229 Handle<mirror::ObjectArray<mirror::Object>> roots, 230 bool has_should_deoptimize_flag, 231 const ArenaSet<ArtMethod*>& cha_single_implementation_list) { 232 uint8_t* result = CommitCodeInternal(self, 233 method, 234 stack_map, 235 method_info, 236 roots_data, 237 frame_size_in_bytes, 238 core_spill_mask, 239 fp_spill_mask, 240 code, 241 code_size, 242 data_size, 243 osr, 244 roots, 245 has_should_deoptimize_flag, 246 cha_single_implementation_list); 247 if (result == nullptr) { 248 // Retry. 249 GarbageCollectCache(self); 250 result = CommitCodeInternal(self, 251 method, 252 stack_map, 253 method_info, 254 roots_data, 255 frame_size_in_bytes, 256 core_spill_mask, 257 fp_spill_mask, 258 code, 259 code_size, 260 data_size, 261 osr, 262 roots, 263 has_should_deoptimize_flag, 264 cha_single_implementation_list); 265 } 266 return result; 267 } 268 269 bool JitCodeCache::WaitForPotentialCollectionToComplete(Thread* self) { 270 bool in_collection = false; 271 while (collection_in_progress_) { 272 in_collection = true; 273 lock_cond_.Wait(self); 274 } 275 return in_collection; 276 } 277 278 static uintptr_t FromCodeToAllocation(const void* code) { 279 size_t alignment = GetInstructionSetAlignment(kRuntimeISA); 280 return reinterpret_cast<uintptr_t>(code) - RoundUp(sizeof(OatQuickMethodHeader), alignment); 281 } 282 283 static uint32_t ComputeRootTableSize(uint32_t number_of_roots) { 284 return sizeof(uint32_t) + number_of_roots * sizeof(GcRoot<mirror::Object>); 285 } 286 287 static uint32_t GetNumberOfRoots(const uint8_t* stack_map) { 288 // The length of the table is stored just before the stack map (and therefore at the end of 289 // the table itself), in order to be able to fetch it from a `stack_map` pointer. 290 return reinterpret_cast<const uint32_t*>(stack_map)[-1]; 291 } 292 293 static void FillRootTableLength(uint8_t* roots_data, uint32_t length) { 294 // Store the length of the table at the end. This will allow fetching it from a `stack_map` 295 // pointer. 296 reinterpret_cast<uint32_t*>(roots_data)[length] = length; 297 } 298 299 static const uint8_t* FromStackMapToRoots(const uint8_t* stack_map_data) { 300 return stack_map_data - ComputeRootTableSize(GetNumberOfRoots(stack_map_data)); 301 } 302 303 static void FillRootTable(uint8_t* roots_data, Handle<mirror::ObjectArray<mirror::Object>> roots) 304 REQUIRES_SHARED(Locks::mutator_lock_) { 305 GcRoot<mirror::Object>* gc_roots = reinterpret_cast<GcRoot<mirror::Object>*>(roots_data); 306 const uint32_t length = roots->GetLength(); 307 // Put all roots in `roots_data`. 308 for (uint32_t i = 0; i < length; ++i) { 309 ObjPtr<mirror::Object> object = roots->Get(i); 310 if (kIsDebugBuild) { 311 // Ensure the string is strongly interned. b/32995596 312 if (object->IsString()) { 313 ObjPtr<mirror::String> str = reinterpret_cast<mirror::String*>(object.Ptr()); 314 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 315 CHECK(class_linker->GetInternTable()->LookupStrong(Thread::Current(), str) != nullptr); 316 } 317 } 318 gc_roots[i] = GcRoot<mirror::Object>(object); 319 } 320 } 321 322 static uint8_t* GetRootTable(const void* code_ptr, uint32_t* number_of_roots = nullptr) { 323 OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromCodePointer(code_ptr); 324 uint8_t* data = method_header->GetOptimizedCodeInfoPtr(); 325 uint32_t roots = GetNumberOfRoots(data); 326 if (number_of_roots != nullptr) { 327 *number_of_roots = roots; 328 } 329 return data - ComputeRootTableSize(roots); 330 } 331 332 // Use a sentinel for marking entries in the JIT table that have been cleared. 333 // This helps diagnosing in case the compiled code tries to wrongly access such 334 // entries. 335 static mirror::Class* const weak_sentinel = reinterpret_cast<mirror::Class*>(0x1); 336 337 // Helper for the GC to process a weak class in a JIT root table. 338 static inline void ProcessWeakClass(GcRoot<mirror::Class>* root_ptr, 339 IsMarkedVisitor* visitor, 340 mirror::Class* update) 341 REQUIRES_SHARED(Locks::mutator_lock_) { 342 // This does not need a read barrier because this is called by GC. 343 mirror::Class* cls = root_ptr->Read<kWithoutReadBarrier>(); 344 if (cls != nullptr && cls != weak_sentinel) { 345 DCHECK((cls->IsClass<kDefaultVerifyFlags, kWithoutReadBarrier>())); 346 // Look at the classloader of the class to know if it has been unloaded. 347 // This does not need a read barrier because this is called by GC. 348 mirror::Object* class_loader = 349 cls->GetClassLoader<kDefaultVerifyFlags, kWithoutReadBarrier>(); 350 if (class_loader == nullptr || visitor->IsMarked(class_loader) != nullptr) { 351 // The class loader is live, update the entry if the class has moved. 352 mirror::Class* new_cls = down_cast<mirror::Class*>(visitor->IsMarked(cls)); 353 // Note that new_object can be null for CMS and newly allocated objects. 354 if (new_cls != nullptr && new_cls != cls) { 355 *root_ptr = GcRoot<mirror::Class>(new_cls); 356 } 357 } else { 358 // The class loader is not live, clear the entry. 359 *root_ptr = GcRoot<mirror::Class>(update); 360 } 361 } 362 } 363 364 void JitCodeCache::SweepRootTables(IsMarkedVisitor* visitor) { 365 MutexLock mu(Thread::Current(), lock_); 366 for (const auto& entry : method_code_map_) { 367 uint32_t number_of_roots = 0; 368 uint8_t* roots_data = GetRootTable(entry.first, &number_of_roots); 369 GcRoot<mirror::Object>* roots = reinterpret_cast<GcRoot<mirror::Object>*>(roots_data); 370 for (uint32_t i = 0; i < number_of_roots; ++i) { 371 // This does not need a read barrier because this is called by GC. 372 mirror::Object* object = roots[i].Read<kWithoutReadBarrier>(); 373 if (object == nullptr || object == weak_sentinel) { 374 // entry got deleted in a previous sweep. 375 } else if (object->IsString<kDefaultVerifyFlags, kWithoutReadBarrier>()) { 376 mirror::Object* new_object = visitor->IsMarked(object); 377 // We know the string is marked because it's a strongly-interned string that 378 // is always alive. The IsMarked implementation of the CMS collector returns 379 // null for newly allocated objects, but we know those haven't moved. Therefore, 380 // only update the entry if we get a different non-null string. 381 // TODO: Do not use IsMarked for j.l.Class, and adjust once we move this method 382 // out of the weak access/creation pause. b/32167580 383 if (new_object != nullptr && new_object != object) { 384 DCHECK(new_object->IsString()); 385 roots[i] = GcRoot<mirror::Object>(new_object); 386 } 387 } else { 388 ProcessWeakClass( 389 reinterpret_cast<GcRoot<mirror::Class>*>(&roots[i]), visitor, weak_sentinel); 390 } 391 } 392 } 393 // Walk over inline caches to clear entries containing unloaded classes. 394 for (ProfilingInfo* info : profiling_infos_) { 395 for (size_t i = 0; i < info->number_of_inline_caches_; ++i) { 396 InlineCache* cache = &info->cache_[i]; 397 for (size_t j = 0; j < InlineCache::kIndividualCacheSize; ++j) { 398 ProcessWeakClass(&cache->classes_[j], visitor, nullptr); 399 } 400 } 401 } 402 } 403 404 void JitCodeCache::FreeCode(const void* code_ptr) { 405 uintptr_t allocation = FromCodeToAllocation(code_ptr); 406 // Notify native debugger that we are about to remove the code. 407 // It does nothing if we are not using native debugger. 408 DeleteJITCodeEntryForAddress(reinterpret_cast<uintptr_t>(code_ptr)); 409 FreeData(GetRootTable(code_ptr)); 410 FreeCode(reinterpret_cast<uint8_t*>(allocation)); 411 } 412 413 void JitCodeCache::FreeAllMethodHeaders( 414 const std::unordered_set<OatQuickMethodHeader*>& method_headers) { 415 { 416 MutexLock mu(Thread::Current(), *Locks::cha_lock_); 417 Runtime::Current()->GetClassHierarchyAnalysis() 418 ->RemoveDependentsWithMethodHeaders(method_headers); 419 } 420 421 // We need to remove entries in method_headers from CHA dependencies 422 // first since once we do FreeCode() below, the memory can be reused 423 // so it's possible for the same method_header to start representing 424 // different compile code. 425 MutexLock mu(Thread::Current(), lock_); 426 ScopedCodeCacheWrite scc(code_map_.get()); 427 for (const OatQuickMethodHeader* method_header : method_headers) { 428 FreeCode(method_header->GetCode()); 429 } 430 } 431 432 void JitCodeCache::RemoveMethodsIn(Thread* self, const LinearAlloc& alloc) { 433 ScopedTrace trace(__PRETTY_FUNCTION__); 434 // We use a set to first collect all method_headers whose code need to be 435 // removed. We need to free the underlying code after we remove CHA dependencies 436 // for entries in this set. And it's more efficient to iterate through 437 // the CHA dependency map just once with an unordered_set. 438 std::unordered_set<OatQuickMethodHeader*> method_headers; 439 { 440 MutexLock mu(self, lock_); 441 // We do not check if a code cache GC is in progress, as this method comes 442 // with the classlinker_classes_lock_ held, and suspending ourselves could 443 // lead to a deadlock. 444 { 445 ScopedCodeCacheWrite scc(code_map_.get()); 446 for (auto it = method_code_map_.begin(); it != method_code_map_.end();) { 447 if (alloc.ContainsUnsafe(it->second)) { 448 method_headers.insert(OatQuickMethodHeader::FromCodePointer(it->first)); 449 it = method_code_map_.erase(it); 450 } else { 451 ++it; 452 } 453 } 454 } 455 for (auto it = osr_code_map_.begin(); it != osr_code_map_.end();) { 456 if (alloc.ContainsUnsafe(it->first)) { 457 // Note that the code has already been pushed to method_headers in the loop 458 // above and is going to be removed in FreeCode() below. 459 it = osr_code_map_.erase(it); 460 } else { 461 ++it; 462 } 463 } 464 for (auto it = profiling_infos_.begin(); it != profiling_infos_.end();) { 465 ProfilingInfo* info = *it; 466 if (alloc.ContainsUnsafe(info->GetMethod())) { 467 info->GetMethod()->SetProfilingInfo(nullptr); 468 FreeData(reinterpret_cast<uint8_t*>(info)); 469 it = profiling_infos_.erase(it); 470 } else { 471 ++it; 472 } 473 } 474 } 475 FreeAllMethodHeaders(method_headers); 476 } 477 478 bool JitCodeCache::IsWeakAccessEnabled(Thread* self) const { 479 return kUseReadBarrier 480 ? self->GetWeakRefAccessEnabled() 481 : is_weak_access_enabled_.LoadSequentiallyConsistent(); 482 } 483 484 void JitCodeCache::WaitUntilInlineCacheAccessible(Thread* self) { 485 if (IsWeakAccessEnabled(self)) { 486 return; 487 } 488 ScopedThreadSuspension sts(self, kWaitingWeakGcRootRead); 489 MutexLock mu(self, lock_); 490 while (!IsWeakAccessEnabled(self)) { 491 inline_cache_cond_.Wait(self); 492 } 493 } 494 495 void JitCodeCache::BroadcastForInlineCacheAccess() { 496 Thread* self = Thread::Current(); 497 MutexLock mu(self, lock_); 498 inline_cache_cond_.Broadcast(self); 499 } 500 501 void JitCodeCache::AllowInlineCacheAccess() { 502 DCHECK(!kUseReadBarrier); 503 is_weak_access_enabled_.StoreSequentiallyConsistent(true); 504 BroadcastForInlineCacheAccess(); 505 } 506 507 void JitCodeCache::DisallowInlineCacheAccess() { 508 DCHECK(!kUseReadBarrier); 509 is_weak_access_enabled_.StoreSequentiallyConsistent(false); 510 } 511 512 void JitCodeCache::CopyInlineCacheInto(const InlineCache& ic, 513 Handle<mirror::ObjectArray<mirror::Class>> array) { 514 WaitUntilInlineCacheAccessible(Thread::Current()); 515 // Note that we don't need to lock `lock_` here, the compiler calling 516 // this method has already ensured the inline cache will not be deleted. 517 for (size_t in_cache = 0, in_array = 0; 518 in_cache < InlineCache::kIndividualCacheSize; 519 ++in_cache) { 520 mirror::Class* object = ic.classes_[in_cache].Read(); 521 if (object != nullptr) { 522 array->Set(in_array++, object); 523 } 524 } 525 } 526 527 uint8_t* JitCodeCache::CommitCodeInternal(Thread* self, 528 ArtMethod* method, 529 uint8_t* stack_map, 530 uint8_t* method_info, 531 uint8_t* roots_data, 532 size_t frame_size_in_bytes, 533 size_t core_spill_mask, 534 size_t fp_spill_mask, 535 const uint8_t* code, 536 size_t code_size, 537 size_t data_size, 538 bool osr, 539 Handle<mirror::ObjectArray<mirror::Object>> roots, 540 bool has_should_deoptimize_flag, 541 const ArenaSet<ArtMethod*>& 542 cha_single_implementation_list) { 543 DCHECK(stack_map != nullptr); 544 size_t alignment = GetInstructionSetAlignment(kRuntimeISA); 545 // Ensure the header ends up at expected instruction alignment. 546 size_t header_size = RoundUp(sizeof(OatQuickMethodHeader), alignment); 547 size_t total_size = header_size + code_size; 548 549 OatQuickMethodHeader* method_header = nullptr; 550 uint8_t* code_ptr = nullptr; 551 uint8_t* memory = nullptr; 552 { 553 ScopedThreadSuspension sts(self, kSuspended); 554 MutexLock mu(self, lock_); 555 WaitForPotentialCollectionToComplete(self); 556 { 557 ScopedCodeCacheWrite scc(code_map_.get()); 558 memory = AllocateCode(total_size); 559 if (memory == nullptr) { 560 return nullptr; 561 } 562 code_ptr = memory + header_size; 563 564 std::copy(code, code + code_size, code_ptr); 565 method_header = OatQuickMethodHeader::FromCodePointer(code_ptr); 566 new (method_header) OatQuickMethodHeader( 567 code_ptr - stack_map, 568 code_ptr - method_info, 569 frame_size_in_bytes, 570 core_spill_mask, 571 fp_spill_mask, 572 code_size); 573 // Flush caches before we remove write permission because some ARMv8 Qualcomm kernels may 574 // trigger a segfault if a page fault occurs when requesting a cache maintenance operation. 575 // This is a kernel bug that we need to work around until affected devices (e.g. Nexus 5X and 576 // 6P) stop being supported or their kernels are fixed. 577 // 578 // For reference, this behavior is caused by this commit: 579 // https://android.googlesource.com/kernel/msm/+/3fbe6bc28a6b9939d0650f2f17eb5216c719950c 580 FlushInstructionCache(reinterpret_cast<char*>(code_ptr), 581 reinterpret_cast<char*>(code_ptr + code_size)); 582 DCHECK(!Runtime::Current()->IsAotCompiler()); 583 if (has_should_deoptimize_flag) { 584 method_header->SetHasShouldDeoptimizeFlag(); 585 } 586 } 587 588 number_of_compilations_++; 589 } 590 // We need to update the entry point in the runnable state for the instrumentation. 591 { 592 // Need cha_lock_ for checking all single-implementation flags and register 593 // dependencies. 594 MutexLock cha_mu(self, *Locks::cha_lock_); 595 bool single_impl_still_valid = true; 596 for (ArtMethod* single_impl : cha_single_implementation_list) { 597 if (!single_impl->HasSingleImplementation()) { 598 // We simply discard the compiled code. Clear the 599 // counter so that it may be recompiled later. Hopefully the 600 // class hierarchy will be more stable when compilation is retried. 601 single_impl_still_valid = false; 602 method->ClearCounter(); 603 break; 604 } 605 } 606 607 // Discard the code if any single-implementation assumptions are now invalid. 608 if (!single_impl_still_valid) { 609 VLOG(jit) << "JIT discarded jitted code due to invalid single-implementation assumptions."; 610 return nullptr; 611 } 612 DCHECK(cha_single_implementation_list.empty() || !Runtime::Current()->IsJavaDebuggable()) 613 << "Should not be using cha on debuggable apps/runs!"; 614 615 for (ArtMethod* single_impl : cha_single_implementation_list) { 616 Runtime::Current()->GetClassHierarchyAnalysis()->AddDependency( 617 single_impl, method, method_header); 618 } 619 620 // The following needs to be guarded by cha_lock_ also. Otherwise it's 621 // possible that the compiled code is considered invalidated by some class linking, 622 // but below we still make the compiled code valid for the method. 623 MutexLock mu(self, lock_); 624 // Fill the root table before updating the entry point. 625 DCHECK_EQ(FromStackMapToRoots(stack_map), roots_data); 626 DCHECK_LE(roots_data, stack_map); 627 FillRootTable(roots_data, roots); 628 { 629 // Flush data cache, as compiled code references literals in it. 630 // We also need a TLB shootdown to act as memory barrier across cores. 631 ScopedCodeCacheWrite ccw(code_map_.get(), /* only_for_tlb_shootdown */ true); 632 FlushDataCache(reinterpret_cast<char*>(roots_data), 633 reinterpret_cast<char*>(roots_data + data_size)); 634 } 635 method_code_map_.Put(code_ptr, method); 636 if (osr) { 637 number_of_osr_compilations_++; 638 osr_code_map_.Put(method, code_ptr); 639 } else { 640 Runtime::Current()->GetInstrumentation()->UpdateMethodsCode( 641 method, method_header->GetEntryPoint()); 642 } 643 if (collection_in_progress_) { 644 // We need to update the live bitmap if there is a GC to ensure it sees this new 645 // code. 646 GetLiveBitmap()->AtomicTestAndSet(FromCodeToAllocation(code_ptr)); 647 } 648 last_update_time_ns_.StoreRelease(NanoTime()); 649 VLOG(jit) 650 << "JIT added (osr=" << std::boolalpha << osr << std::noboolalpha << ") " 651 << ArtMethod::PrettyMethod(method) << "@" << method 652 << " ccache_size=" << PrettySize(CodeCacheSizeLocked()) << ": " 653 << " dcache_size=" << PrettySize(DataCacheSizeLocked()) << ": " 654 << reinterpret_cast<const void*>(method_header->GetEntryPoint()) << "," 655 << reinterpret_cast<const void*>(method_header->GetEntryPoint() + 656 method_header->GetCodeSize()); 657 histogram_code_memory_use_.AddValue(code_size); 658 if (code_size > kCodeSizeLogThreshold) { 659 LOG(INFO) << "JIT allocated " 660 << PrettySize(code_size) 661 << " for compiled code of " 662 << ArtMethod::PrettyMethod(method); 663 } 664 } 665 666 return reinterpret_cast<uint8_t*>(method_header); 667 } 668 669 size_t JitCodeCache::CodeCacheSize() { 670 MutexLock mu(Thread::Current(), lock_); 671 return CodeCacheSizeLocked(); 672 } 673 674 // This notifies the code cache that the given method has been redefined and that it should remove 675 // any cached information it has on the method. All threads must be suspended before calling this 676 // method. The compiled code for the method (if there is any) must not be in any threads call stack. 677 void JitCodeCache::NotifyMethodRedefined(ArtMethod* method) { 678 MutexLock mu(Thread::Current(), lock_); 679 if (method->IsNative()) { 680 return; 681 } 682 ProfilingInfo* info = method->GetProfilingInfo(kRuntimePointerSize); 683 if (info != nullptr) { 684 auto profile = std::find(profiling_infos_.begin(), profiling_infos_.end(), info); 685 DCHECK(profile != profiling_infos_.end()); 686 profiling_infos_.erase(profile); 687 } 688 method->SetProfilingInfo(nullptr); 689 ScopedCodeCacheWrite ccw(code_map_.get()); 690 for (auto code_iter = method_code_map_.begin(); code_iter != method_code_map_.end();) { 691 if (code_iter->second == method) { 692 FreeCode(code_iter->first); 693 code_iter = method_code_map_.erase(code_iter); 694 continue; 695 } 696 ++code_iter; 697 } 698 auto code_map = osr_code_map_.find(method); 699 if (code_map != osr_code_map_.end()) { 700 osr_code_map_.erase(code_map); 701 } 702 } 703 704 // This invalidates old_method. Once this function returns one can no longer use old_method to 705 // execute code unless it is fixed up. This fixup will happen later in the process of installing a 706 // class redefinition. 707 // TODO We should add some info to ArtMethod to note that 'old_method' has been invalidated and 708 // shouldn't be used since it is no longer logically in the jit code cache. 709 // TODO We should add DCHECKS that validate that the JIT is paused when this method is entered. 710 void JitCodeCache::MoveObsoleteMethod(ArtMethod* old_method, ArtMethod* new_method) { 711 // Native methods have no profiling info and need no special handling from the JIT code cache. 712 if (old_method->IsNative()) { 713 return; 714 } 715 MutexLock mu(Thread::Current(), lock_); 716 // Update ProfilingInfo to the new one and remove it from the old_method. 717 if (old_method->GetProfilingInfo(kRuntimePointerSize) != nullptr) { 718 DCHECK_EQ(old_method->GetProfilingInfo(kRuntimePointerSize)->GetMethod(), old_method); 719 ProfilingInfo* info = old_method->GetProfilingInfo(kRuntimePointerSize); 720 old_method->SetProfilingInfo(nullptr); 721 // Since the JIT should be paused and all threads suspended by the time this is called these 722 // checks should always pass. 723 DCHECK(!info->IsInUseByCompiler()); 724 new_method->SetProfilingInfo(info); 725 info->method_ = new_method; 726 } 727 // Update method_code_map_ to point to the new method. 728 for (auto& it : method_code_map_) { 729 if (it.second == old_method) { 730 it.second = new_method; 731 } 732 } 733 // Update osr_code_map_ to point to the new method. 734 auto code_map = osr_code_map_.find(old_method); 735 if (code_map != osr_code_map_.end()) { 736 osr_code_map_.Put(new_method, code_map->second); 737 osr_code_map_.erase(old_method); 738 } 739 } 740 741 size_t JitCodeCache::CodeCacheSizeLocked() { 742 return used_memory_for_code_; 743 } 744 745 size_t JitCodeCache::DataCacheSize() { 746 MutexLock mu(Thread::Current(), lock_); 747 return DataCacheSizeLocked(); 748 } 749 750 size_t JitCodeCache::DataCacheSizeLocked() { 751 return used_memory_for_data_; 752 } 753 754 void JitCodeCache::ClearData(Thread* self, 755 uint8_t* stack_map_data, 756 uint8_t* roots_data) { 757 DCHECK_EQ(FromStackMapToRoots(stack_map_data), roots_data); 758 MutexLock mu(self, lock_); 759 FreeData(reinterpret_cast<uint8_t*>(roots_data)); 760 } 761 762 size_t JitCodeCache::ReserveData(Thread* self, 763 size_t stack_map_size, 764 size_t method_info_size, 765 size_t number_of_roots, 766 ArtMethod* method, 767 uint8_t** stack_map_data, 768 uint8_t** method_info_data, 769 uint8_t** roots_data) { 770 size_t table_size = ComputeRootTableSize(number_of_roots); 771 size_t size = RoundUp(stack_map_size + method_info_size + table_size, sizeof(void*)); 772 uint8_t* result = nullptr; 773 774 { 775 ScopedThreadSuspension sts(self, kSuspended); 776 MutexLock mu(self, lock_); 777 WaitForPotentialCollectionToComplete(self); 778 result = AllocateData(size); 779 } 780 781 if (result == nullptr) { 782 // Retry. 783 GarbageCollectCache(self); 784 ScopedThreadSuspension sts(self, kSuspended); 785 MutexLock mu(self, lock_); 786 WaitForPotentialCollectionToComplete(self); 787 result = AllocateData(size); 788 } 789 790 MutexLock mu(self, lock_); 791 histogram_stack_map_memory_use_.AddValue(size); 792 if (size > kStackMapSizeLogThreshold) { 793 LOG(INFO) << "JIT allocated " 794 << PrettySize(size) 795 << " for stack maps of " 796 << ArtMethod::PrettyMethod(method); 797 } 798 if (result != nullptr) { 799 *roots_data = result; 800 *stack_map_data = result + table_size; 801 *method_info_data = *stack_map_data + stack_map_size; 802 FillRootTableLength(*roots_data, number_of_roots); 803 return size; 804 } else { 805 *roots_data = nullptr; 806 *stack_map_data = nullptr; 807 *method_info_data = nullptr; 808 return 0; 809 } 810 } 811 812 class MarkCodeVisitor FINAL : public StackVisitor { 813 public: 814 MarkCodeVisitor(Thread* thread_in, JitCodeCache* code_cache_in) 815 : StackVisitor(thread_in, nullptr, StackVisitor::StackWalkKind::kSkipInlinedFrames), 816 code_cache_(code_cache_in), 817 bitmap_(code_cache_->GetLiveBitmap()) {} 818 819 bool VisitFrame() OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) { 820 const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader(); 821 if (method_header == nullptr) { 822 return true; 823 } 824 const void* code = method_header->GetCode(); 825 if (code_cache_->ContainsPc(code)) { 826 // Use the atomic set version, as multiple threads are executing this code. 827 bitmap_->AtomicTestAndSet(FromCodeToAllocation(code)); 828 } 829 return true; 830 } 831 832 private: 833 JitCodeCache* const code_cache_; 834 CodeCacheBitmap* const bitmap_; 835 }; 836 837 class MarkCodeClosure FINAL : public Closure { 838 public: 839 MarkCodeClosure(JitCodeCache* code_cache, Barrier* barrier) 840 : code_cache_(code_cache), barrier_(barrier) {} 841 842 void Run(Thread* thread) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) { 843 ScopedTrace trace(__PRETTY_FUNCTION__); 844 DCHECK(thread == Thread::Current() || thread->IsSuspended()); 845 MarkCodeVisitor visitor(thread, code_cache_); 846 visitor.WalkStack(); 847 if (kIsDebugBuild) { 848 // The stack walking code queries the side instrumentation stack if it 849 // sees an instrumentation exit pc, so the JIT code of methods in that stack 850 // must have been seen. We sanity check this below. 851 for (const instrumentation::InstrumentationStackFrame& frame 852 : *thread->GetInstrumentationStack()) { 853 // The 'method_' in InstrumentationStackFrame is the one that has return_pc_ in 854 // its stack frame, it is not the method owning return_pc_. We just pass null to 855 // LookupMethodHeader: the method is only checked against in debug builds. 856 OatQuickMethodHeader* method_header = 857 code_cache_->LookupMethodHeader(frame.return_pc_, nullptr); 858 if (method_header != nullptr) { 859 const void* code = method_header->GetCode(); 860 CHECK(code_cache_->GetLiveBitmap()->Test(FromCodeToAllocation(code))); 861 } 862 } 863 } 864 barrier_->Pass(Thread::Current()); 865 } 866 867 private: 868 JitCodeCache* const code_cache_; 869 Barrier* const barrier_; 870 }; 871 872 void JitCodeCache::NotifyCollectionDone(Thread* self) { 873 collection_in_progress_ = false; 874 lock_cond_.Broadcast(self); 875 } 876 877 void JitCodeCache::SetFootprintLimit(size_t new_footprint) { 878 size_t per_space_footprint = new_footprint / 2; 879 DCHECK(IsAlignedParam(per_space_footprint, kPageSize)); 880 DCHECK_EQ(per_space_footprint * 2, new_footprint); 881 mspace_set_footprint_limit(data_mspace_, per_space_footprint); 882 { 883 ScopedCodeCacheWrite scc(code_map_.get()); 884 mspace_set_footprint_limit(code_mspace_, per_space_footprint); 885 } 886 } 887 888 bool JitCodeCache::IncreaseCodeCacheCapacity() { 889 if (current_capacity_ == max_capacity_) { 890 return false; 891 } 892 893 // Double the capacity if we're below 1MB, or increase it by 1MB if 894 // we're above. 895 if (current_capacity_ < 1 * MB) { 896 current_capacity_ *= 2; 897 } else { 898 current_capacity_ += 1 * MB; 899 } 900 if (current_capacity_ > max_capacity_) { 901 current_capacity_ = max_capacity_; 902 } 903 904 if (!kIsDebugBuild || VLOG_IS_ON(jit)) { 905 LOG(INFO) << "Increasing code cache capacity to " << PrettySize(current_capacity_); 906 } 907 908 SetFootprintLimit(current_capacity_); 909 910 return true; 911 } 912 913 void JitCodeCache::MarkCompiledCodeOnThreadStacks(Thread* self) { 914 Barrier barrier(0); 915 size_t threads_running_checkpoint = 0; 916 MarkCodeClosure closure(this, &barrier); 917 threads_running_checkpoint = Runtime::Current()->GetThreadList()->RunCheckpoint(&closure); 918 // Now that we have run our checkpoint, move to a suspended state and wait 919 // for other threads to run the checkpoint. 920 ScopedThreadSuspension sts(self, kSuspended); 921 if (threads_running_checkpoint != 0) { 922 barrier.Increment(self, threads_running_checkpoint); 923 } 924 } 925 926 bool JitCodeCache::ShouldDoFullCollection() { 927 if (current_capacity_ == max_capacity_) { 928 // Always do a full collection when the code cache is full. 929 return true; 930 } else if (current_capacity_ < kReservedCapacity) { 931 // Always do partial collection when the code cache size is below the reserved 932 // capacity. 933 return false; 934 } else if (last_collection_increased_code_cache_) { 935 // This time do a full collection. 936 return true; 937 } else { 938 // This time do a partial collection. 939 return false; 940 } 941 } 942 943 void JitCodeCache::GarbageCollectCache(Thread* self) { 944 ScopedTrace trace(__FUNCTION__); 945 if (!garbage_collect_code_) { 946 MutexLock mu(self, lock_); 947 IncreaseCodeCacheCapacity(); 948 return; 949 } 950 951 // Wait for an existing collection, or let everyone know we are starting one. 952 { 953 ScopedThreadSuspension sts(self, kSuspended); 954 MutexLock mu(self, lock_); 955 if (WaitForPotentialCollectionToComplete(self)) { 956 return; 957 } else { 958 number_of_collections_++; 959 live_bitmap_.reset(CodeCacheBitmap::Create( 960 "code-cache-bitmap", 961 reinterpret_cast<uintptr_t>(code_map_->Begin()), 962 reinterpret_cast<uintptr_t>(code_map_->Begin() + current_capacity_ / 2))); 963 collection_in_progress_ = true; 964 } 965 } 966 967 TimingLogger logger("JIT code cache timing logger", true, VLOG_IS_ON(jit)); 968 { 969 TimingLogger::ScopedTiming st("Code cache collection", &logger); 970 971 bool do_full_collection = false; 972 { 973 MutexLock mu(self, lock_); 974 do_full_collection = ShouldDoFullCollection(); 975 } 976 977 if (!kIsDebugBuild || VLOG_IS_ON(jit)) { 978 LOG(INFO) << "Do " 979 << (do_full_collection ? "full" : "partial") 980 << " code cache collection, code=" 981 << PrettySize(CodeCacheSize()) 982 << ", data=" << PrettySize(DataCacheSize()); 983 } 984 985 DoCollection(self, /* collect_profiling_info */ do_full_collection); 986 987 if (!kIsDebugBuild || VLOG_IS_ON(jit)) { 988 LOG(INFO) << "After code cache collection, code=" 989 << PrettySize(CodeCacheSize()) 990 << ", data=" << PrettySize(DataCacheSize()); 991 } 992 993 { 994 MutexLock mu(self, lock_); 995 996 // Increase the code cache only when we do partial collections. 997 // TODO: base this strategy on how full the code cache is? 998 if (do_full_collection) { 999 last_collection_increased_code_cache_ = false; 1000 } else { 1001 last_collection_increased_code_cache_ = true; 1002 IncreaseCodeCacheCapacity(); 1003 } 1004 1005 bool next_collection_will_be_full = ShouldDoFullCollection(); 1006 1007 // Start polling the liveness of compiled code to prepare for the next full collection. 1008 if (next_collection_will_be_full) { 1009 // Save the entry point of methods we have compiled, and update the entry 1010 // point of those methods to the interpreter. If the method is invoked, the 1011 // interpreter will update its entry point to the compiled code and call it. 1012 for (ProfilingInfo* info : profiling_infos_) { 1013 const void* entry_point = info->GetMethod()->GetEntryPointFromQuickCompiledCode(); 1014 if (ContainsPc(entry_point)) { 1015 info->SetSavedEntryPoint(entry_point); 1016 // Don't call Instrumentation::UpdateMethods, as it can check the declaring 1017 // class of the method. We may be concurrently running a GC which makes accessing 1018 // the class unsafe. We know it is OK to bypass the instrumentation as we've just 1019 // checked that the current entry point is JIT compiled code. 1020 info->GetMethod()->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 1021 } 1022 } 1023 1024 DCHECK(CheckLiveCompiledCodeHasProfilingInfo()); 1025 } 1026 live_bitmap_.reset(nullptr); 1027 NotifyCollectionDone(self); 1028 } 1029 } 1030 Runtime::Current()->GetJit()->AddTimingLogger(logger); 1031 } 1032 1033 void JitCodeCache::RemoveUnmarkedCode(Thread* self) { 1034 ScopedTrace trace(__FUNCTION__); 1035 std::unordered_set<OatQuickMethodHeader*> method_headers; 1036 { 1037 MutexLock mu(self, lock_); 1038 ScopedCodeCacheWrite scc(code_map_.get()); 1039 // Iterate over all compiled code and remove entries that are not marked. 1040 for (auto it = method_code_map_.begin(); it != method_code_map_.end();) { 1041 const void* code_ptr = it->first; 1042 uintptr_t allocation = FromCodeToAllocation(code_ptr); 1043 if (GetLiveBitmap()->Test(allocation)) { 1044 ++it; 1045 } else { 1046 method_headers.insert(OatQuickMethodHeader::FromCodePointer(it->first)); 1047 it = method_code_map_.erase(it); 1048 } 1049 } 1050 } 1051 FreeAllMethodHeaders(method_headers); 1052 } 1053 1054 void JitCodeCache::DoCollection(Thread* self, bool collect_profiling_info) { 1055 ScopedTrace trace(__FUNCTION__); 1056 { 1057 MutexLock mu(self, lock_); 1058 if (collect_profiling_info) { 1059 // Clear the profiling info of methods that do not have compiled code as entrypoint. 1060 // Also remove the saved entry point from the ProfilingInfo objects. 1061 for (ProfilingInfo* info : profiling_infos_) { 1062 const void* ptr = info->GetMethod()->GetEntryPointFromQuickCompiledCode(); 1063 if (!ContainsPc(ptr) && !info->IsInUseByCompiler()) { 1064 info->GetMethod()->SetProfilingInfo(nullptr); 1065 } 1066 1067 if (info->GetSavedEntryPoint() != nullptr) { 1068 info->SetSavedEntryPoint(nullptr); 1069 // We are going to move this method back to interpreter. Clear the counter now to 1070 // give it a chance to be hot again. 1071 info->GetMethod()->ClearCounter(); 1072 } 1073 } 1074 } else if (kIsDebugBuild) { 1075 // Sanity check that the profiling infos do not have a dangling entry point. 1076 for (ProfilingInfo* info : profiling_infos_) { 1077 DCHECK(info->GetSavedEntryPoint() == nullptr); 1078 } 1079 } 1080 1081 // Mark compiled code that are entrypoints of ArtMethods. Compiled code that is not 1082 // an entry point is either: 1083 // - an osr compiled code, that will be removed if not in a thread call stack. 1084 // - discarded compiled code, that will be removed if not in a thread call stack. 1085 for (const auto& it : method_code_map_) { 1086 ArtMethod* method = it.second; 1087 const void* code_ptr = it.first; 1088 const OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromCodePointer(code_ptr); 1089 if (method_header->GetEntryPoint() == method->GetEntryPointFromQuickCompiledCode()) { 1090 GetLiveBitmap()->AtomicTestAndSet(FromCodeToAllocation(code_ptr)); 1091 } 1092 } 1093 1094 // Empty osr method map, as osr compiled code will be deleted (except the ones 1095 // on thread stacks). 1096 osr_code_map_.clear(); 1097 } 1098 1099 // Run a checkpoint on all threads to mark the JIT compiled code they are running. 1100 MarkCompiledCodeOnThreadStacks(self); 1101 1102 // At this point, mutator threads are still running, and entrypoints of methods can 1103 // change. We do know they cannot change to a code cache entry that is not marked, 1104 // therefore we can safely remove those entries. 1105 RemoveUnmarkedCode(self); 1106 1107 if (collect_profiling_info) { 1108 ScopedThreadSuspension sts(self, kSuspended); 1109 MutexLock mu(self, lock_); 1110 // Free all profiling infos of methods not compiled nor being compiled. 1111 auto profiling_kept_end = std::remove_if(profiling_infos_.begin(), profiling_infos_.end(), 1112 [this] (ProfilingInfo* info) NO_THREAD_SAFETY_ANALYSIS { 1113 const void* ptr = info->GetMethod()->GetEntryPointFromQuickCompiledCode(); 1114 // We have previously cleared the ProfilingInfo pointer in the ArtMethod in the hope 1115 // that the compiled code would not get revived. As mutator threads run concurrently, 1116 // they may have revived the compiled code, and now we are in the situation where 1117 // a method has compiled code but no ProfilingInfo. 1118 // We make sure compiled methods have a ProfilingInfo object. It is needed for 1119 // code cache collection. 1120 if (ContainsPc(ptr) && 1121 info->GetMethod()->GetProfilingInfo(kRuntimePointerSize) == nullptr) { 1122 info->GetMethod()->SetProfilingInfo(info); 1123 } else if (info->GetMethod()->GetProfilingInfo(kRuntimePointerSize) != info) { 1124 // No need for this ProfilingInfo object anymore. 1125 FreeData(reinterpret_cast<uint8_t*>(info)); 1126 return true; 1127 } 1128 return false; 1129 }); 1130 profiling_infos_.erase(profiling_kept_end, profiling_infos_.end()); 1131 DCHECK(CheckLiveCompiledCodeHasProfilingInfo()); 1132 } 1133 } 1134 1135 bool JitCodeCache::CheckLiveCompiledCodeHasProfilingInfo() { 1136 ScopedTrace trace(__FUNCTION__); 1137 // Check that methods we have compiled do have a ProfilingInfo object. We would 1138 // have memory leaks of compiled code otherwise. 1139 for (const auto& it : method_code_map_) { 1140 ArtMethod* method = it.second; 1141 if (method->GetProfilingInfo(kRuntimePointerSize) == nullptr) { 1142 const void* code_ptr = it.first; 1143 const OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromCodePointer(code_ptr); 1144 if (method_header->GetEntryPoint() == method->GetEntryPointFromQuickCompiledCode()) { 1145 // If the code is not dead, then we have a problem. Note that this can even 1146 // happen just after a collection, as mutator threads are running in parallel 1147 // and could deoptimize an existing compiled code. 1148 return false; 1149 } 1150 } 1151 } 1152 return true; 1153 } 1154 1155 OatQuickMethodHeader* JitCodeCache::LookupMethodHeader(uintptr_t pc, ArtMethod* method) { 1156 static_assert(kRuntimeISA != kThumb2, "kThumb2 cannot be a runtime ISA"); 1157 if (kRuntimeISA == kArm) { 1158 // On Thumb-2, the pc is offset by one. 1159 --pc; 1160 } 1161 if (!ContainsPc(reinterpret_cast<const void*>(pc))) { 1162 return nullptr; 1163 } 1164 1165 MutexLock mu(Thread::Current(), lock_); 1166 if (method_code_map_.empty()) { 1167 return nullptr; 1168 } 1169 auto it = method_code_map_.lower_bound(reinterpret_cast<const void*>(pc)); 1170 --it; 1171 1172 const void* code_ptr = it->first; 1173 OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromCodePointer(code_ptr); 1174 if (!method_header->Contains(pc)) { 1175 return nullptr; 1176 } 1177 if (kIsDebugBuild && method != nullptr) { 1178 // When we are walking the stack to redefine classes and creating obsolete methods it is 1179 // possible that we might have updated the method_code_map by making this method obsolete in a 1180 // previous frame. Therefore we should just check that the non-obsolete version of this method 1181 // is the one we expect. We change to the non-obsolete versions in the error message since the 1182 // obsolete version of the method might not be fully initialized yet. This situation can only 1183 // occur when we are in the process of allocating and setting up obsolete methods. Otherwise 1184 // method and it->second should be identical. (See runtime/openjdkjvmti/ti_redefine.cc for more 1185 // information.) 1186 DCHECK_EQ(it->second->GetNonObsoleteMethod(), method->GetNonObsoleteMethod()) 1187 << ArtMethod::PrettyMethod(method->GetNonObsoleteMethod()) << " " 1188 << ArtMethod::PrettyMethod(it->second->GetNonObsoleteMethod()) << " " 1189 << std::hex << pc; 1190 } 1191 return method_header; 1192 } 1193 1194 OatQuickMethodHeader* JitCodeCache::LookupOsrMethodHeader(ArtMethod* method) { 1195 MutexLock mu(Thread::Current(), lock_); 1196 auto it = osr_code_map_.find(method); 1197 if (it == osr_code_map_.end()) { 1198 return nullptr; 1199 } 1200 return OatQuickMethodHeader::FromCodePointer(it->second); 1201 } 1202 1203 ProfilingInfo* JitCodeCache::AddProfilingInfo(Thread* self, 1204 ArtMethod* method, 1205 const std::vector<uint32_t>& entries, 1206 bool retry_allocation) 1207 // No thread safety analysis as we are using TryLock/Unlock explicitly. 1208 NO_THREAD_SAFETY_ANALYSIS { 1209 ProfilingInfo* info = nullptr; 1210 if (!retry_allocation) { 1211 // If we are allocating for the interpreter, just try to lock, to avoid 1212 // lock contention with the JIT. 1213 if (lock_.ExclusiveTryLock(self)) { 1214 info = AddProfilingInfoInternal(self, method, entries); 1215 lock_.ExclusiveUnlock(self); 1216 } 1217 } else { 1218 { 1219 MutexLock mu(self, lock_); 1220 info = AddProfilingInfoInternal(self, method, entries); 1221 } 1222 1223 if (info == nullptr) { 1224 GarbageCollectCache(self); 1225 MutexLock mu(self, lock_); 1226 info = AddProfilingInfoInternal(self, method, entries); 1227 } 1228 } 1229 return info; 1230 } 1231 1232 ProfilingInfo* JitCodeCache::AddProfilingInfoInternal(Thread* self ATTRIBUTE_UNUSED, 1233 ArtMethod* method, 1234 const std::vector<uint32_t>& entries) { 1235 size_t profile_info_size = RoundUp( 1236 sizeof(ProfilingInfo) + sizeof(InlineCache) * entries.size(), 1237 sizeof(void*)); 1238 1239 // Check whether some other thread has concurrently created it. 1240 ProfilingInfo* info = method->GetProfilingInfo(kRuntimePointerSize); 1241 if (info != nullptr) { 1242 return info; 1243 } 1244 1245 uint8_t* data = AllocateData(profile_info_size); 1246 if (data == nullptr) { 1247 return nullptr; 1248 } 1249 info = new (data) ProfilingInfo(method, entries); 1250 1251 // Make sure other threads see the data in the profiling info object before the 1252 // store in the ArtMethod's ProfilingInfo pointer. 1253 QuasiAtomic::ThreadFenceRelease(); 1254 1255 method->SetProfilingInfo(info); 1256 profiling_infos_.push_back(info); 1257 histogram_profiling_info_memory_use_.AddValue(profile_info_size); 1258 return info; 1259 } 1260 1261 // NO_THREAD_SAFETY_ANALYSIS as this is called from mspace code, at which point the lock 1262 // is already held. 1263 void* JitCodeCache::MoreCore(const void* mspace, intptr_t increment) NO_THREAD_SAFETY_ANALYSIS { 1264 if (code_mspace_ == mspace) { 1265 size_t result = code_end_; 1266 code_end_ += increment; 1267 return reinterpret_cast<void*>(result + code_map_->Begin()); 1268 } else { 1269 DCHECK_EQ(data_mspace_, mspace); 1270 size_t result = data_end_; 1271 data_end_ += increment; 1272 return reinterpret_cast<void*>(result + data_map_->Begin()); 1273 } 1274 } 1275 1276 void JitCodeCache::GetProfiledMethods(const std::set<std::string>& dex_base_locations, 1277 std::vector<ProfileMethodInfo>& methods) { 1278 ScopedTrace trace(__FUNCTION__); 1279 MutexLock mu(Thread::Current(), lock_); 1280 uint16_t jit_compile_threshold = Runtime::Current()->GetJITOptions()->GetCompileThreshold(); 1281 for (const ProfilingInfo* info : profiling_infos_) { 1282 ArtMethod* method = info->GetMethod(); 1283 const DexFile* dex_file = method->GetDexFile(); 1284 if (!ContainsElement(dex_base_locations, dex_file->GetBaseLocation())) { 1285 // Skip dex files which are not profiled. 1286 continue; 1287 } 1288 std::vector<ProfileMethodInfo::ProfileInlineCache> inline_caches; 1289 1290 // If the method didn't reach the compilation threshold don't save the inline caches. 1291 // They might be incomplete and cause unnecessary deoptimizations. 1292 // If the inline cache is empty the compiler will generate a regular invoke virtual/interface. 1293 if (method->GetCounter() < jit_compile_threshold) { 1294 methods.emplace_back(/*ProfileMethodInfo*/ 1295 dex_file, method->GetDexMethodIndex(), inline_caches); 1296 continue; 1297 } 1298 1299 for (size_t i = 0; i < info->number_of_inline_caches_; ++i) { 1300 std::vector<ProfileMethodInfo::ProfileClassReference> profile_classes; 1301 const InlineCache& cache = info->cache_[i]; 1302 ArtMethod* caller = info->GetMethod(); 1303 bool is_missing_types = false; 1304 for (size_t k = 0; k < InlineCache::kIndividualCacheSize; k++) { 1305 mirror::Class* cls = cache.classes_[k].Read(); 1306 if (cls == nullptr) { 1307 break; 1308 } 1309 1310 // Check if the receiver is in the boot class path or if it's in the 1311 // same class loader as the caller. If not, skip it, as there is not 1312 // much we can do during AOT. 1313 if (!cls->IsBootStrapClassLoaded() && 1314 caller->GetClassLoader() != cls->GetClassLoader()) { 1315 is_missing_types = true; 1316 continue; 1317 } 1318 1319 const DexFile* class_dex_file = nullptr; 1320 dex::TypeIndex type_index; 1321 1322 if (cls->GetDexCache() == nullptr) { 1323 DCHECK(cls->IsArrayClass()) << cls->PrettyClass(); 1324 // Make a best effort to find the type index in the method's dex file. 1325 // We could search all open dex files but that might turn expensive 1326 // and probably not worth it. 1327 class_dex_file = dex_file; 1328 type_index = cls->FindTypeIndexInOtherDexFile(*dex_file); 1329 } else { 1330 class_dex_file = &(cls->GetDexFile()); 1331 type_index = cls->GetDexTypeIndex(); 1332 } 1333 if (!type_index.IsValid()) { 1334 // Could be a proxy class or an array for which we couldn't find the type index. 1335 is_missing_types = true; 1336 continue; 1337 } 1338 if (ContainsElement(dex_base_locations, class_dex_file->GetBaseLocation())) { 1339 // Only consider classes from the same apk (including multidex). 1340 profile_classes.emplace_back(/*ProfileMethodInfo::ProfileClassReference*/ 1341 class_dex_file, type_index); 1342 } else { 1343 is_missing_types = true; 1344 } 1345 } 1346 if (!profile_classes.empty()) { 1347 inline_caches.emplace_back(/*ProfileMethodInfo::ProfileInlineCache*/ 1348 cache.dex_pc_, is_missing_types, profile_classes); 1349 } 1350 } 1351 methods.emplace_back(/*ProfileMethodInfo*/ 1352 dex_file, method->GetDexMethodIndex(), inline_caches); 1353 } 1354 } 1355 1356 uint64_t JitCodeCache::GetLastUpdateTimeNs() const { 1357 return last_update_time_ns_.LoadAcquire(); 1358 } 1359 1360 bool JitCodeCache::IsOsrCompiled(ArtMethod* method) { 1361 MutexLock mu(Thread::Current(), lock_); 1362 return osr_code_map_.find(method) != osr_code_map_.end(); 1363 } 1364 1365 bool JitCodeCache::NotifyCompilationOf(ArtMethod* method, Thread* self, bool osr) { 1366 if (!osr && ContainsPc(method->GetEntryPointFromQuickCompiledCode())) { 1367 return false; 1368 } 1369 1370 MutexLock mu(self, lock_); 1371 if (osr && (osr_code_map_.find(method) != osr_code_map_.end())) { 1372 return false; 1373 } 1374 1375 ProfilingInfo* info = method->GetProfilingInfo(kRuntimePointerSize); 1376 if (info == nullptr) { 1377 VLOG(jit) << method->PrettyMethod() << " needs a ProfilingInfo to be compiled"; 1378 // Because the counter is not atomic, there are some rare cases where we may not 1379 // hit the threshold for creating the ProfilingInfo. Reset the counter now to 1380 // "correct" this. 1381 method->ClearCounter(); 1382 return false; 1383 } 1384 1385 if (info->IsMethodBeingCompiled(osr)) { 1386 return false; 1387 } 1388 1389 info->SetIsMethodBeingCompiled(true, osr); 1390 return true; 1391 } 1392 1393 ProfilingInfo* JitCodeCache::NotifyCompilerUse(ArtMethod* method, Thread* self) { 1394 MutexLock mu(self, lock_); 1395 ProfilingInfo* info = method->GetProfilingInfo(kRuntimePointerSize); 1396 if (info != nullptr) { 1397 if (!info->IncrementInlineUse()) { 1398 // Overflow of inlining uses, just bail. 1399 return nullptr; 1400 } 1401 } 1402 return info; 1403 } 1404 1405 void JitCodeCache::DoneCompilerUse(ArtMethod* method, Thread* self) { 1406 MutexLock mu(self, lock_); 1407 ProfilingInfo* info = method->GetProfilingInfo(kRuntimePointerSize); 1408 DCHECK(info != nullptr); 1409 info->DecrementInlineUse(); 1410 } 1411 1412 void JitCodeCache::DoneCompiling(ArtMethod* method, Thread* self ATTRIBUTE_UNUSED, bool osr) { 1413 ProfilingInfo* info = method->GetProfilingInfo(kRuntimePointerSize); 1414 DCHECK(info->IsMethodBeingCompiled(osr)); 1415 info->SetIsMethodBeingCompiled(false, osr); 1416 } 1417 1418 size_t JitCodeCache::GetMemorySizeOfCodePointer(const void* ptr) { 1419 MutexLock mu(Thread::Current(), lock_); 1420 return mspace_usable_size(reinterpret_cast<const void*>(FromCodeToAllocation(ptr))); 1421 } 1422 1423 void JitCodeCache::InvalidateCompiledCodeFor(ArtMethod* method, 1424 const OatQuickMethodHeader* header) { 1425 ProfilingInfo* profiling_info = method->GetProfilingInfo(kRuntimePointerSize); 1426 if ((profiling_info != nullptr) && 1427 (profiling_info->GetSavedEntryPoint() == header->GetEntryPoint())) { 1428 // Prevent future uses of the compiled code. 1429 profiling_info->SetSavedEntryPoint(nullptr); 1430 } 1431 1432 if (method->GetEntryPointFromQuickCompiledCode() == header->GetEntryPoint()) { 1433 // The entrypoint is the one to invalidate, so we just update 1434 // it to the interpreter entry point and clear the counter to get the method 1435 // Jitted again. 1436 Runtime::Current()->GetInstrumentation()->UpdateMethodsCode( 1437 method, GetQuickToInterpreterBridge()); 1438 method->ClearCounter(); 1439 } else { 1440 MutexLock mu(Thread::Current(), lock_); 1441 auto it = osr_code_map_.find(method); 1442 if (it != osr_code_map_.end() && OatQuickMethodHeader::FromCodePointer(it->second) == header) { 1443 // Remove the OSR method, to avoid using it again. 1444 osr_code_map_.erase(it); 1445 } 1446 } 1447 } 1448 1449 uint8_t* JitCodeCache::AllocateCode(size_t code_size) { 1450 size_t alignment = GetInstructionSetAlignment(kRuntimeISA); 1451 uint8_t* result = reinterpret_cast<uint8_t*>( 1452 mspace_memalign(code_mspace_, alignment, code_size)); 1453 size_t header_size = RoundUp(sizeof(OatQuickMethodHeader), alignment); 1454 // Ensure the header ends up at expected instruction alignment. 1455 DCHECK_ALIGNED_PARAM(reinterpret_cast<uintptr_t>(result + header_size), alignment); 1456 used_memory_for_code_ += mspace_usable_size(result); 1457 return result; 1458 } 1459 1460 void JitCodeCache::FreeCode(uint8_t* code) { 1461 used_memory_for_code_ -= mspace_usable_size(code); 1462 mspace_free(code_mspace_, code); 1463 } 1464 1465 uint8_t* JitCodeCache::AllocateData(size_t data_size) { 1466 void* result = mspace_malloc(data_mspace_, data_size); 1467 used_memory_for_data_ += mspace_usable_size(result); 1468 return reinterpret_cast<uint8_t*>(result); 1469 } 1470 1471 void JitCodeCache::FreeData(uint8_t* data) { 1472 used_memory_for_data_ -= mspace_usable_size(data); 1473 mspace_free(data_mspace_, data); 1474 } 1475 1476 void JitCodeCache::Dump(std::ostream& os) { 1477 MutexLock mu(Thread::Current(), lock_); 1478 os << "Current JIT code cache size: " << PrettySize(used_memory_for_code_) << "\n" 1479 << "Current JIT data cache size: " << PrettySize(used_memory_for_data_) << "\n" 1480 << "Current JIT capacity: " << PrettySize(current_capacity_) << "\n" 1481 << "Current number of JIT code cache entries: " << method_code_map_.size() << "\n" 1482 << "Total number of JIT compilations: " << number_of_compilations_ << "\n" 1483 << "Total number of JIT compilations for on stack replacement: " 1484 << number_of_osr_compilations_ << "\n" 1485 << "Total number of JIT code cache collections: " << number_of_collections_ << std::endl; 1486 histogram_stack_map_memory_use_.PrintMemoryUse(os); 1487 histogram_code_memory_use_.PrintMemoryUse(os); 1488 histogram_profiling_info_memory_use_.PrintMemoryUse(os); 1489 } 1490 1491 } // namespace jit 1492 } // namespace art 1493
