1 /* 2 * Copyright (c) 1997, 2017, 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_VM_CODE_CODECACHE_HPP 26 #define SHARE_VM_CODE_CODECACHE_HPP 27 28 #include "code/codeBlob.hpp" 29 #include "code/nmethod.hpp" 30 #include "memory/allocation.hpp" 31 #include "memory/heap.hpp" 32 #include "oops/instanceKlass.hpp" 33 #include "oops/oopsHierarchy.hpp" 34 #include "runtime/mutexLocker.hpp" 35 36 // The CodeCache implements the code cache for various pieces of generated 37 // code, e.g., compiled java methods, runtime stubs, transition frames, etc. 38 // The entries in the CodeCache are all CodeBlob's. 39 40 // -- Implementation -- 41 // The CodeCache consists of one or more CodeHeaps, each of which contains 42 // CodeBlobs of a specific CodeBlobType. Currently heaps for the following 43 // types are available: 44 // - Non-nmethods: Non-nmethods like Buffers, Adapters and Runtime Stubs 45 // - Profiled nmethods: nmethods that are profiled, i.e., those 46 // executed at level 2 or 3 47 // - Non-Profiled nmethods: nmethods that are not profiled, i.e., those 48 // executed at level 1 or 4 and native methods 49 // - All: Used for code of all types if code cache segmentation is disabled. 50 // 51 // In the rare case of the non-nmethod code heap getting full, non-nmethod code 52 // will be stored in the non-profiled code heap as a fallback solution. 53 // 54 // Depending on the availability of compilers and TieredCompilation there 55 // may be fewer heaps. The size of the code heaps depends on the values of 56 // ReservedCodeCacheSize, NonProfiledCodeHeapSize and ProfiledCodeHeapSize 57 // (see CodeCache::heap_available(..) and CodeCache::initialize_heaps(..) 58 // for details). 59 // 60 // Code cache segmentation is controlled by the flag SegmentedCodeCache. 61 // If turned off, all code types are stored in a single code heap. By default 62 // code cache segmentation is turned on if TieredCompilation is enabled and 63 // ReservedCodeCacheSize >= 240 MB. 64 // 65 // All methods of the CodeCache accepting a CodeBlobType only apply to 66 // CodeBlobs of the given type. For example, iteration over the 67 // CodeBlobs of a specific type can be done by using CodeCache::first_blob(..) 68 // and CodeCache::next_blob(..) and providing the corresponding CodeBlobType. 69 // 70 // IMPORTANT: If you add new CodeHeaps to the code cache or change the 71 // existing ones, make sure to adapt the dtrace scripts (jhelper.d) for 72 // Solaris and BSD. 73 74 class OopClosure; 75 class KlassDepChange; 76 77 class CodeCache : AllStatic { 78 friend class VMStructs; 79 friend class JVMCIVMStructs; 80 template <class T, class Filter> friend class CodeBlobIterator; 81 friend class WhiteBox; 82 friend class CodeCacheLoader; 83 private: 84 // CodeHeaps of the cache 85 static GrowableArray<CodeHeap*>* _heaps; 86 static GrowableArray<CodeHeap*>* _compiled_heaps; 87 static GrowableArray<CodeHeap*>* _nmethod_heaps; 88 static GrowableArray<CodeHeap*>* _allocable_heaps; 89 90 static address _low_bound; // Lower bound of CodeHeap addresses 91 static address _high_bound; // Upper bound of CodeHeap addresses 92 static int _number_of_nmethods_with_dependencies; // Total number of nmethods with dependencies 93 static bool _needs_cache_clean; // True if inline caches of the nmethods needs to be flushed 94 static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link() 95 96 static void mark_scavenge_root_nmethods() PRODUCT_RETURN; 97 static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN; 98 99 // CodeHeap management 100 static void initialize_heaps(); // Initializes the CodeHeaps 101 // Check the code heap sizes set by the user via command line 102 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); 103 // Creates a new heap with the given name and size, containing CodeBlobs of the given type 104 static void add_heap(ReservedSpace rs, const char* name, int code_blob_type); 105 static CodeHeap* get_code_heap_containing(void* p); // Returns the CodeHeap containing the given pointer, or NULL 106 static CodeHeap* get_code_heap(const CodeBlob* cb); // Returns the CodeHeap for the given CodeBlob 107 static CodeHeap* get_code_heap(int code_blob_type); // Returns the CodeHeap for the given CodeBlobType 108 // Returns the name of the VM option to set the size of the corresponding CodeHeap 109 static const char* get_code_heap_flag_name(int code_blob_type); 110 static size_t page_size(bool aligned = true); // Returns the page size used by the CodeCache 111 static ReservedCodeSpace reserve_heap_memory(size_t size); // Reserves one continuous chunk of memory for the CodeHeaps 112 113 // Iteration 114 static CodeBlob* first_blob(CodeHeap* heap); // Returns the first CodeBlob on the given CodeHeap 115 static CodeBlob* first_blob(int code_blob_type); // Returns the first CodeBlob of the given type 116 static CodeBlob* next_blob(CodeHeap* heap, CodeBlob* cb); // Returns the next CodeBlob on the given CodeHeap 117 118 static size_t bytes_allocated_in_freelists(); 119 static int allocated_segments(); 120 static size_t freelists_length(); 121 122 static void set_scavenge_root_nmethods(nmethod* nm) { _scavenge_root_nmethods = nm; } 123 static void prune_scavenge_root_nmethods(); 124 static void unlink_scavenge_root_nmethod(nmethod* nm, nmethod* prev); 125 126 // Make private to prevent unsafe calls. Not all CodeBlob*'s are embedded in a CodeHeap. 127 static bool contains(CodeBlob *p) { fatal("don't call me!"); return false; } 128 129 public: 130 // Initialization 131 static void initialize(); 132 133 static int code_heap_compare(CodeHeap* const &lhs, CodeHeap* const &rhs); 134 135 static void add_heap(CodeHeap* heap); 136 static const GrowableArray<CodeHeap*>* heaps() { return _heaps; } 137 static const GrowableArray<CodeHeap*>* compiled_heaps() { return _compiled_heaps; } 138 static const GrowableArray<CodeHeap*>* nmethod_heaps() { return _nmethod_heaps; } 139 140 // Allocation/administration 141 static CodeBlob* allocate(int size, int code_blob_type, int orig_code_blob_type = CodeBlobType::All); // allocates a new CodeBlob 142 static void commit(CodeBlob* cb); // called when the allocated CodeBlob has been filled 143 static int alignment_unit(); // guaranteed alignment of all CodeBlobs 144 static int alignment_offset(); // guaranteed offset of first CodeBlob byte within alignment unit (i.e., allocation header) 145 static void free(CodeBlob* cb); // frees a CodeBlob 146 static void free_unused_tail(CodeBlob* cb, size_t used); // frees the unused tail of a CodeBlob (only used by TemplateInterpreter::initialize()) 147 static bool contains(void *p); // returns whether p is included 148 static bool contains(nmethod* nm); // returns whether nm is included 149 static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs 150 static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs 151 static void nmethods_do(void f(nmethod* nm)); // iterates over all nmethods 152 static void metadata_do(void f(Metadata* m)); // iterates over metadata in alive nmethods 153 154 // Lookup 155 static CodeBlob* find_blob(void* start); // Returns the CodeBlob containing the given address 156 static CodeBlob* find_blob_unsafe(void* start); // Same as find_blob but does not fail if looking up a zombie method 157 static nmethod* find_nmethod(void* start); // Returns the nmethod containing the given address 158 static CompiledMethod* find_compiled(void* start); 159 160 static int blob_count(); // Returns the total number of CodeBlobs in the cache 161 static int blob_count(int code_blob_type); 162 static int adapter_count(); // Returns the total number of Adapters in the cache 163 static int adapter_count(int code_blob_type); 164 static int nmethod_count(); // Returns the total number of nmethods in the cache 165 static int nmethod_count(int code_blob_type); 166 167 // GC support 168 static void gc_epilogue(); 169 static void gc_prologue(); 170 static void verify_oops(); 171 // If "unloading_occurred" is true, then unloads (i.e., breaks root links 172 // to) any unmarked codeBlobs in the cache. Sets "marked_for_unloading" 173 // to "true" iff some code got unloaded. 174 static void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred); 175 static void asserted_non_scavengable_nmethods_do(CodeBlobClosure* f = NULL) PRODUCT_RETURN; 176 177 // Apply f to every live code blob in scavengable nmethods. Prune nmethods 178 // from the list of scavengable nmethods if f->fix_relocations() and a nmethod 179 // no longer has scavengable oops. If f->fix_relocations(), then f must copy 180 // objects to their new location immediately to avoid fixing nmethods on the 181 // basis of the old object locations. 182 static void scavenge_root_nmethods_do(CodeBlobToOopClosure* f); 183 184 static nmethod* scavenge_root_nmethods() { return _scavenge_root_nmethods; } 185 // register_scavenge_root_nmethod() conditionally adds the nmethod to the list 186 // if it is not already on the list and has a scavengeable root 187 static void register_scavenge_root_nmethod(nmethod* nm); 188 static void verify_scavenge_root_nmethod(nmethod* nm); 189 static void add_scavenge_root_nmethod(nmethod* nm); 190 static void drop_scavenge_root_nmethod(nmethod* nm); 191 192 // Printing/debugging 193 static void print(); // prints summary 194 static void print_internals(); 195 static void print_memory_overhead(); 196 static void verify(); // verifies the code cache 197 static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN; 198 static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage 199 static void log_state(outputStream* st); 200 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"); } 201 static void report_codemem_full(int code_blob_type, bool print); 202 203 // Dcmd (Diagnostic commands) 204 static void print_codelist(outputStream* st); 205 static void print_layout(outputStream* st); 206 207 // The full limits of the codeCache 208 static address low_bound() { return _low_bound; } 209 static address low_bound(int code_blob_type); 210 static address high_bound() { return _high_bound; } 211 static address high_bound(int code_blob_type); 212 213 // Have to use far call instructions to call this pc. 214 static bool is_far_target(address pc); 215 216 // Profiling 217 static size_t capacity(); 218 static size_t unallocated_capacity(int code_blob_type); 219 static size_t unallocated_capacity(); 220 static size_t max_capacity(); 221 222 static double reverse_free_ratio(int code_blob_type); 223 224 static bool needs_cache_clean() { return _needs_cache_clean; } 225 static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; } 226 static void clear_inline_caches(); // clear all inline caches 227 static void cleanup_inline_caches(); 228 229 // Returns true if an own CodeHeap for the given CodeBlobType is available 230 static bool heap_available(int code_blob_type); 231 232 // Returns the CodeBlobType for the given CompiledMethod 233 static int get_code_blob_type(CompiledMethod* cm) { 234 return get_code_heap(cm)->code_blob_type(); 235 } 236 237 static bool code_blob_type_accepts_compiled(int type) { 238 bool result = type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled; 239 AOT_ONLY( result = result || type == CodeBlobType::AOT; ) 240 return result; 241 } 242 243 static bool code_blob_type_accepts_nmethod(int type) { 244 return type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled; 245 } 246 247 static bool code_blob_type_accepts_allocable(int type) { 248 return type <= CodeBlobType::All; 249 } 250 251 252 // Returns the CodeBlobType for the given compilation level 253 static int get_code_blob_type(int comp_level) { 254 if (comp_level == CompLevel_none || 255 comp_level == CompLevel_simple || 256 comp_level == CompLevel_full_optimization) { 257 // Non profiled methods 258 return CodeBlobType::MethodNonProfiled; 259 } else if (comp_level == CompLevel_limited_profile || 260 comp_level == CompLevel_full_profile) { 261 // Profiled methods 262 return CodeBlobType::MethodProfiled; 263 } 264 ShouldNotReachHere(); 265 return 0; 266 } 267 268 static void verify_clean_inline_caches(); 269 static void verify_icholder_relocations(); 270 271 // Deoptimization 272 private: 273 static int mark_for_deoptimization(KlassDepChange& changes); 274 #ifdef HOTSWAP 275 static int mark_for_evol_deoptimization(InstanceKlass* dependee); 276 #endif // HOTSWAP 277 278 public: 279 static void mark_all_nmethods_for_deoptimization(); 280 static int mark_for_deoptimization(Method* dependee); 281 static void make_marked_nmethods_not_entrant(); 282 283 // Flushing and deoptimization 284 static void flush_dependents_on(InstanceKlass* dependee); 285 #ifdef HOTSWAP 286 // Flushing and deoptimization in case of evolution 287 static void flush_evol_dependents_on(InstanceKlass* dependee); 288 #endif // HOTSWAP 289 // Support for fullspeed debugging 290 static void flush_dependents_on_method(const methodHandle& dependee); 291 292 // tells how many nmethods have dependencies 293 static int number_of_nmethods_with_dependencies(); 294 295 static int get_codemem_full_count(int code_blob_type) { 296 CodeHeap* heap = get_code_heap(code_blob_type); 297 return (heap != NULL) ? heap->full_count() : 0; 298 } 299 }; 300 301 302 // Iterator to iterate over nmethods in the CodeCache. 303 template <class T, class Filter> class CodeBlobIterator : public StackObj { 304 private: 305 CodeBlob* _code_blob; // Current CodeBlob 306 GrowableArrayIterator<CodeHeap*> _heap; 307 GrowableArrayIterator<CodeHeap*> _end; 308 309 public: 310 CodeBlobIterator(T* nm = NULL) { 311 if (Filter::heaps() == NULL) { 312 return; 313 } 314 _heap = Filter::heaps()->begin(); 315 _end = Filter::heaps()->end(); 316 // If set to NULL, initialized by first call to next() 317 _code_blob = (CodeBlob*)nm; 318 if (nm != NULL) { 319 while(!(*_heap)->contains_blob(_code_blob)) { 320 ++_heap; 321 } 322 assert((*_heap)->contains_blob(_code_blob), "match not found"); 323 } 324 } 325 326 // Advance iterator to next blob 327 bool next() { 328 assert_locked_or_safepoint(CodeCache_lock); 329 330 bool result = next_blob(); 331 while (!result && _heap != _end) { 332 // Advance to next code heap of segmented code cache 333 if (++_heap == _end) { 334 break; 335 } 336 result = next_blob(); 337 } 338 339 return result; 340 } 341 342 // Advance iterator to next alive blob 343 bool next_alive() { 344 bool result = next(); 345 while(result && !_code_blob->is_alive()) { 346 result = next(); 347 } 348 return result; 349 } 350 351 bool end() const { return _code_blob == NULL; } 352 T* method() const { return (T*)_code_blob; } 353 354 private: 355 356 // Advance iterator to the next blob in the current code heap 357 bool next_blob() { 358 if (_heap == _end) { 359 return false; 360 } 361 CodeHeap *heap = *_heap; 362 // Get first method CodeBlob 363 if (_code_blob == NULL) { 364 _code_blob = CodeCache::first_blob(heap); 365 if (_code_blob == NULL) { 366 return false; 367 } else if (Filter::apply(_code_blob)) { 368 return true; 369 } 370 } 371 // Search for next method CodeBlob 372 _code_blob = CodeCache::next_blob(heap, _code_blob); 373 while (_code_blob != NULL && !Filter::apply(_code_blob)) { 374 _code_blob = CodeCache::next_blob(heap, _code_blob); 375 } 376 return _code_blob != NULL; 377 } 378 }; 379 380 381 struct CompiledMethodFilter { 382 static bool apply(CodeBlob* cb) { return cb->is_compiled(); } 383 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::compiled_heaps(); } 384 }; 385 386 387 struct NMethodFilter { 388 static bool apply(CodeBlob* cb) { return cb->is_nmethod(); } 389 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::nmethod_heaps(); } 390 }; 391 392 393 typedef CodeBlobIterator<CompiledMethod, CompiledMethodFilter> CompiledMethodIterator; 394 typedef CodeBlobIterator<nmethod, NMethodFilter> NMethodIterator; 395 396 #endif // SHARE_VM_CODE_CODECACHE_HPP