1 /* 2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_CODE_CODECACHE_HPP 26 #define SHARE_CODE_CODECACHE_HPP 27 28 #include "code/codeBlob.hpp" 29 #include "code/nmethod.hpp" 30 #include "gc/shared/gcBehaviours.hpp" 31 #include "memory/allocation.hpp" 32 #include "memory/heap.hpp" 33 #include "oops/instanceKlass.hpp" 34 #include "oops/oopsHierarchy.hpp" 35 #include "runtime/mutexLocker.hpp" 36 37 // The CodeCache implements the code cache for various pieces of generated 38 // code, e.g., compiled java methods, runtime stubs, transition frames, etc. 39 // The entries in the CodeCache are all CodeBlob's. 40 41 // -- Implementation -- 42 // The CodeCache consists of one or more CodeHeaps, each of which contains 43 // CodeBlobs of a specific CodeBlobType. Currently heaps for the following 44 // types are available: 45 // - Non-nmethods: Non-nmethods like Buffers, Adapters and Runtime Stubs 46 // - Profiled nmethods: nmethods that are profiled, i.e., those 47 // executed at level 2 or 3 48 // - Non-Profiled nmethods: nmethods that are not profiled, i.e., those 49 // executed at level 1 or 4 and native methods 50 // - All: Used for code of all types if code cache segmentation is disabled. 51 // 52 // In the rare case of the non-nmethod code heap getting full, non-nmethod code 53 // will be stored in the non-profiled code heap as a fallback solution. 54 // 55 // Depending on the availability of compilers and TieredCompilation there 56 // may be fewer heaps. The size of the code heaps depends on the values of 57 // ReservedCodeCacheSize, NonProfiledCodeHeapSize and ProfiledCodeHeapSize 58 // (see CodeCache::heap_available(..) and CodeCache::initialize_heaps(..) 59 // for details). 60 // 61 // Code cache segmentation is controlled by the flag SegmentedCodeCache. 62 // If turned off, all code types are stored in a single code heap. By default 63 // code cache segmentation is turned on if TieredCompilation is enabled and 64 // ReservedCodeCacheSize >= 240 MB. 65 // 66 // All methods of the CodeCache accepting a CodeBlobType only apply to 67 // CodeBlobs of the given type. For example, iteration over the 68 // CodeBlobs of a specific type can be done by using CodeCache::first_blob(..) 69 // and CodeCache::next_blob(..) and providing the corresponding CodeBlobType. 70 // 71 // IMPORTANT: If you add new CodeHeaps to the code cache or change the 72 // existing ones, make sure to adapt the dtrace scripts (jhelper.d) for 73 // Solaris and BSD. 74 75 class ExceptionCache; 76 class KlassDepChange; 77 class OopClosure; 78 class ShenandoahParallelCodeHeapIterator; 79 80 class CodeCache : AllStatic { 81 friend class VMStructs; 82 friend class JVMCIVMStructs; 83 template <class T, class Filter> friend class CodeBlobIterator; 84 friend class WhiteBox; 85 friend class CodeCacheLoader; 86 friend class ShenandoahParallelCodeHeapIterator; 87 private: 88 // CodeHeaps of the cache 89 static GrowableArray<CodeHeap*>* _heaps; 90 static GrowableArray<CodeHeap*>* _compiled_heaps; 91 static GrowableArray<CodeHeap*>* _nmethod_heaps; 92 static GrowableArray<CodeHeap*>* _allocable_heaps; 93 94 static address _low_bound; // Lower bound of CodeHeap addresses 95 static address _high_bound; // Upper bound of CodeHeap addresses 96 static int _number_of_nmethods_with_dependencies; // Total number of nmethods with dependencies 97 static uint8_t _unloading_cycle; // Global state for recognizing old nmethods that need to be unloaded 98 99 static ExceptionCache* volatile _exception_cache_purge_list; 100 101 // CodeHeap management 102 static void initialize_heaps(); // Initializes the CodeHeaps 103 // Check the code heap sizes set by the user via command line 104 static void check_heap_sizes(size_t non_nmethod_size, size_t profiled_size, size_t non_profiled_size, size_t cache_size, bool all_set); 105 // Creates a new heap with the given name and size, containing CodeBlobs of the given type 106 static void add_heap(ReservedSpace rs, const char* name, int code_blob_type); 107 static CodeHeap* get_code_heap_containing(void* p); // Returns the CodeHeap containing the given pointer, or NULL 108 static CodeHeap* get_code_heap(const CodeBlob* cb); // Returns the CodeHeap for the given CodeBlob 109 static CodeHeap* get_code_heap(int code_blob_type); // Returns the CodeHeap for the given CodeBlobType 110 // Returns the name of the VM option to set the size of the corresponding CodeHeap 111 static const char* get_code_heap_flag_name(int code_blob_type); 112 static ReservedCodeSpace reserve_heap_memory(size_t size); // Reserves one continuous chunk of memory for the CodeHeaps 113 114 // Iteration 115 static CodeBlob* first_blob(CodeHeap* heap); // Returns the first CodeBlob on the given CodeHeap 116 static CodeBlob* first_blob(int code_blob_type); // Returns the first CodeBlob of the given type 117 static CodeBlob* next_blob(CodeHeap* heap, CodeBlob* cb); // Returns the next CodeBlob on the given CodeHeap 118 119 static size_t bytes_allocated_in_freelists(); 120 static int allocated_segments(); 121 static size_t freelists_length(); 122 123 // Make private to prevent unsafe calls. Not all CodeBlob*'s are embedded in a CodeHeap. 124 static bool contains(CodeBlob *p) { fatal("don't call me!"); return false; } 125 126 public: 127 // Initialization 128 static void initialize(); 129 static size_t page_size(bool aligned = true, size_t min_pages = 1); // Returns the page size used by the CodeCache 130 131 static int code_heap_compare(CodeHeap* const &lhs, CodeHeap* const &rhs); 132 133 static void add_heap(CodeHeap* heap); 134 static const GrowableArray<CodeHeap*>* heaps() { return _heaps; } 135 static const GrowableArray<CodeHeap*>* compiled_heaps() { return _compiled_heaps; } 136 static const GrowableArray<CodeHeap*>* nmethod_heaps() { return _nmethod_heaps; } 137 138 // Allocation/administration 139 static CodeBlob* allocate(int size, int code_blob_type, int orig_code_blob_type = CodeBlobType::All); // allocates a new CodeBlob 140 static void commit(CodeBlob* cb); // called when the allocated CodeBlob has been filled 141 static int alignment_unit(); // guaranteed alignment of all CodeBlobs 142 static int alignment_offset(); // guaranteed offset of first CodeBlob byte within alignment unit (i.e., allocation header) 143 static void free(CodeBlob* cb); // frees a CodeBlob 144 static void free_unused_tail(CodeBlob* cb, size_t used); // frees the unused tail of a CodeBlob (only used by TemplateInterpreter::initialize()) 145 static bool contains(void *p); // returns whether p is included 146 static bool contains(nmethod* nm); // returns whether nm is included 147 static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs 148 static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs 149 static void nmethods_do(void f(nmethod* nm)); // iterates over all nmethods 150 static void metadata_do(void f(Metadata* m)); // iterates over metadata in alive nmethods 151 152 // Lookup 153 static CodeBlob* find_blob(void* start); // Returns the CodeBlob containing the given address 154 static CodeBlob* find_blob_unsafe(void* start); // Same as find_blob but does not fail if looking up a zombie method 155 static nmethod* find_nmethod(void* start); // Returns the nmethod containing the given address 156 static CompiledMethod* find_compiled(void* start); 157 158 static int blob_count(); // Returns the total number of CodeBlobs in the cache 159 static int blob_count(int code_blob_type); 160 static int adapter_count(); // Returns the total number of Adapters in the cache 161 static int adapter_count(int code_blob_type); 162 static int nmethod_count(); // Returns the total number of nmethods in the cache 163 static int nmethod_count(int code_blob_type); 164 165 // GC support 166 static void verify_oops(); 167 // If any oops are not marked this method unloads (i.e., breaks root links 168 // to) any unmarked codeBlobs in the cache. Sets "marked_for_unloading" 169 // to "true" iff some code got unloaded. 170 // "unloading_occurred" controls whether metadata should be cleaned because of class unloading. 171 class UnloadingScope: StackObj { 172 ClosureIsUnloadingBehaviour _is_unloading_behaviour; 173 174 public: 175 UnloadingScope(BoolObjectClosure* is_alive); 176 ~UnloadingScope(); 177 }; 178 179 static void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred); 180 static uint8_t unloading_cycle() { return _unloading_cycle; } 181 static void increment_unloading_cycle(); 182 static void release_exception_cache(ExceptionCache* entry); 183 static void purge_exception_caches(); 184 185 // Printing/debugging 186 static void print(); // prints summary 187 static void print_internals(); 188 static void print_memory_overhead(); 189 static void verify(); // verifies the code cache 190 static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN; 191 static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage 192 static void log_state(outputStream* st); 193 static const char* get_code_heap_name(int code_blob_type) { return (heap_available(code_blob_type) ? get_code_heap(code_blob_type)->name() : "Unused"); } 194 static void report_codemem_full(int code_blob_type, bool print); 195 196 // Dcmd (Diagnostic commands) 197 static void print_codelist(outputStream* st); 198 static void print_layout(outputStream* st); 199 200 // The full limits of the codeCache 201 static address low_bound() { return _low_bound; } 202 static address low_bound(int code_blob_type); 203 static address high_bound() { return _high_bound; } 204 static address high_bound(int code_blob_type); 205 206 // Have to use far call instructions to call this pc. 207 static bool is_far_target(address pc); 208 209 // Profiling 210 static size_t capacity(); 211 static size_t unallocated_capacity(int code_blob_type); 212 static size_t unallocated_capacity(); 213 static size_t max_capacity(); 214 215 static double reverse_free_ratio(int code_blob_type); 216 217 static void clear_inline_caches(); // clear all inline caches 218 static void cleanup_inline_caches(); // clean unloaded/zombie nmethods from inline caches 219 220 // Returns true if an own CodeHeap for the given CodeBlobType is available 221 static bool heap_available(int code_blob_type); 222 223 // Returns the CodeBlobType for the given CompiledMethod 224 static int get_code_blob_type(CompiledMethod* cm) { 225 return get_code_heap(cm)->code_blob_type(); 226 } 227 228 static bool code_blob_type_accepts_compiled(int type) { 229 bool result = type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled; 230 AOT_ONLY( result = result || type == CodeBlobType::AOT; ) 231 return result; 232 } 233 234 static bool code_blob_type_accepts_nmethod(int type) { 235 return type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled; 236 } 237 238 static bool code_blob_type_accepts_allocable(int type) { 239 return type <= CodeBlobType::All; 240 } 241 242 243 // Returns the CodeBlobType for the given compilation level 244 static int get_code_blob_type(int comp_level) { 245 if (comp_level == CompLevel_none || 246 comp_level == CompLevel_simple || 247 comp_level == CompLevel_full_optimization) { 248 // Non profiled methods 249 return CodeBlobType::MethodNonProfiled; 250 } else if (comp_level == CompLevel_limited_profile || 251 comp_level == CompLevel_full_profile) { 252 // Profiled methods 253 return CodeBlobType::MethodProfiled; 254 } 255 ShouldNotReachHere(); 256 return 0; 257 } 258 259 static void verify_clean_inline_caches(); 260 static void verify_icholder_relocations(); 261 262 // Deoptimization 263 private: 264 static int mark_for_deoptimization(KlassDepChange& changes); 265 266 public: 267 static void mark_all_nmethods_for_deoptimization(); 268 static int mark_for_deoptimization(Method* dependee); 269 static void make_marked_nmethods_not_entrant(); 270 271 // Flushing and deoptimization 272 static void flush_dependents_on(InstanceKlass* dependee); 273 // Flushing and deoptimization in case of evolution 274 static void mark_for_evol_deoptimization(InstanceKlass* dependee); 275 static int mark_dependents_for_evol_deoptimization(); 276 static void flush_evol_dependents(); 277 // Support for fullspeed debugging 278 static void flush_dependents_on_method(const methodHandle& dependee); 279 280 // tells how many nmethods have dependencies 281 static int number_of_nmethods_with_dependencies(); 282 283 static int get_codemem_full_count(int code_blob_type) { 284 CodeHeap* heap = get_code_heap(code_blob_type); 285 return (heap != NULL) ? heap->full_count() : 0; 286 } 287 288 // CodeHeap State Analytics. 289 // interface methods for CodeHeap printing, called by CompileBroker 290 static void aggregate(outputStream *out, const char* granularity); 291 static void discard(outputStream *out); 292 static void print_usedSpace(outputStream *out); 293 static void print_freeSpace(outputStream *out); 294 static void print_count(outputStream *out); 295 static void print_space(outputStream *out); 296 static void print_age(outputStream *out); 297 static void print_names(outputStream *out); 298 }; 299 300 301 // Iterator to iterate over nmethods in the CodeCache. 302 template <class T, class Filter> class CodeBlobIterator : public StackObj { 303 public: 304 enum LivenessFilter { all_blobs, only_alive, only_alive_and_not_unloading }; 305 306 private: 307 CodeBlob* _code_blob; // Current CodeBlob 308 GrowableArrayIterator<CodeHeap*> _heap; 309 GrowableArrayIterator<CodeHeap*> _end; 310 bool _only_alive; 311 bool _only_not_unloading; 312 313 public: 314 CodeBlobIterator(LivenessFilter filter, T* nm = NULL) 315 : _only_alive(filter == only_alive || filter == only_alive_and_not_unloading), 316 _only_not_unloading(filter == only_alive_and_not_unloading) 317 { 318 if (Filter::heaps() == NULL) { 319 return; 320 } 321 _heap = Filter::heaps()->begin(); 322 _end = Filter::heaps()->end(); 323 // If set to NULL, initialized by first call to next() 324 _code_blob = (CodeBlob*)nm; 325 if (nm != NULL) { 326 while(!(*_heap)->contains_blob(_code_blob)) { 327 ++_heap; 328 } 329 assert((*_heap)->contains_blob(_code_blob), "match not found"); 330 } 331 } 332 333 // Advance iterator to next blob 334 bool next() { 335 assert_locked_or_safepoint(CodeCache_lock); 336 337 for (;;) { 338 // Walk through heaps as required 339 if (!next_blob()) { 340 if (_heap == _end) { 341 return false; 342 } 343 ++_heap; 344 continue; 345 } 346 347 // Filter is_alive as required 348 if (_only_alive && !_code_blob->is_alive()) { 349 continue; 350 } 351 352 // Filter is_unloading as required 353 if (_only_not_unloading) { 354 CompiledMethod* cm = _code_blob->as_compiled_method_or_null(); 355 if (cm != NULL && cm->is_unloading()) { 356 continue; 357 } 358 } 359 360 return true; 361 } 362 } 363 364 bool end() const { return _code_blob == NULL; } 365 T* method() const { return (T*)_code_blob; } 366 367 private: 368 369 // Advance iterator to the next blob in the current code heap 370 bool next_blob() { 371 if (_heap == _end) { 372 return false; 373 } 374 CodeHeap *heap = *_heap; 375 // Get first method CodeBlob 376 if (_code_blob == NULL) { 377 _code_blob = CodeCache::first_blob(heap); 378 if (_code_blob == NULL) { 379 return false; 380 } else if (Filter::apply(_code_blob)) { 381 return true; 382 } 383 } 384 // Search for next method CodeBlob 385 _code_blob = CodeCache::next_blob(heap, _code_blob); 386 while (_code_blob != NULL && !Filter::apply(_code_blob)) { 387 _code_blob = CodeCache::next_blob(heap, _code_blob); 388 } 389 return _code_blob != NULL; 390 } 391 }; 392 393 394 struct CompiledMethodFilter { 395 static bool apply(CodeBlob* cb) { return cb->is_compiled(); } 396 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::compiled_heaps(); } 397 }; 398 399 400 struct NMethodFilter { 401 static bool apply(CodeBlob* cb) { return cb->is_nmethod(); } 402 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::nmethod_heaps(); } 403 }; 404 405 typedef CodeBlobIterator<CompiledMethod, CompiledMethodFilter> CompiledMethodIterator; 406 typedef CodeBlobIterator<nmethod, NMethodFilter> NMethodIterator; 407 408 #endif // SHARE_CODE_CODECACHE_HPP