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 89 static address _low_bound; // Lower bound of CodeHeap addresses 90 static address _high_bound; // Upper bound of CodeHeap addresses 91 static int _number_of_nmethods_with_dependencies; // Total number of nmethods with dependencies 92 static bool _needs_cache_clean; // True if inline caches of the nmethods needs to be flushed 93 static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link() 94 95 static void mark_scavenge_root_nmethods() PRODUCT_RETURN; 96 static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN; 97 98 // CodeHeap management 99 static void initialize_heaps(); // Initializes the CodeHeaps 100 // Check the code heap sizes set by the user via command line 101 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); 102 // Creates a new heap with the given name and size, containing CodeBlobs of the given type 103 static void add_heap(ReservedSpace rs, const char* name, int code_blob_type); 104 static CodeHeap* get_code_heap(const CodeBlob* cb); // Returns the CodeHeap for the given CodeBlob 105 static CodeHeap* get_code_heap(int code_blob_type); // Returns the CodeHeap for the given CodeBlobType 106 // Returns the name of the VM option to set the size of the corresponding CodeHeap 107 static const char* get_code_heap_flag_name(int code_blob_type); 108 static size_t heap_alignment(); // Returns the alignment of the CodeHeaps in bytes 109 static ReservedCodeSpace reserve_heap_memory(size_t size); // Reserves one continuous chunk of memory for the CodeHeaps 110 111 // Iteration 112 static CodeBlob* first_blob(CodeHeap* heap); // Returns the first CodeBlob on the given CodeHeap 113 static CodeBlob* first_blob(int code_blob_type); // Returns the first CodeBlob of the given type 114 static CodeBlob* next_blob(CodeHeap* heap, CodeBlob* cb); // Returns the next CodeBlob on the given CodeHeap 115 116 static size_t bytes_allocated_in_freelists(); 117 static int allocated_segments(); 118 static size_t freelists_length(); 119 120 static void set_scavenge_root_nmethods(nmethod* nm) { _scavenge_root_nmethods = nm; } 121 static void prune_scavenge_root_nmethods(); 122 static void unlink_scavenge_root_nmethod(nmethod* nm, nmethod* prev); 123 124 // Make private to prevent unsafe calls. Not all CodeBlob*'s are embedded in a CodeHeap. 125 static bool contains(CodeBlob *p) { fatal("don't call me!"); return false; } 126 127 public: 128 // Initialization 129 static void initialize(); 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 bool contains(void *p); // returns whether p is included 145 static bool contains(nmethod* nm); // returns whether nm is included 146 static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs 147 static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs 148 static void nmethods_do(void f(nmethod* nm)); // iterates over all nmethods 149 static void metadata_do(void f(Metadata* m)); // iterates over metadata in alive nmethods 150 151 // Lookup 152 static CodeBlob* find_blob(void* start); // Returns the CodeBlob containing the given address 153 static CodeBlob* find_blob_unsafe(void* start); // Same as find_blob but does not fail if looking up a zombie method 154 static nmethod* find_nmethod(void* start); // Returns the nmethod containing the given address 155 static CompiledMethod* find_compiled(void* start); 156 157 static int blob_count(); // Returns the total number of CodeBlobs in the cache 158 static int blob_count(int code_blob_type); 159 static int adapter_count(); // Returns the total number of Adapters in the cache 160 static int adapter_count(int code_blob_type); 161 static int nmethod_count(); // Returns the total number of nmethods in the cache 162 static int nmethod_count(int code_blob_type); 163 164 // GC support 165 static void gc_epilogue(); 166 static void gc_prologue(); 167 static void verify_oops(); 168 // If "unloading_occurred" is true, then unloads (i.e., breaks root links 169 // to) any unmarked codeBlobs in the cache. Sets "marked_for_unloading" 170 // to "true" iff some code got unloaded. 171 static void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred); 172 static void asserted_non_scavengable_nmethods_do(CodeBlobClosure* f = NULL) PRODUCT_RETURN; 173 174 // Apply f to every live code blob in scavengable nmethods. Prune nmethods 175 // from the list of scavengable nmethods if f->fix_relocations() and a nmethod 176 // no longer has scavengable oops. If f->fix_relocations(), then f must copy 177 // objects to their new location immediately to avoid fixing nmethods on the 178 // basis of the old object locations. 179 static void scavenge_root_nmethods_do(CodeBlobToOopClosure* f); 180 181 static nmethod* scavenge_root_nmethods() { return _scavenge_root_nmethods; } 182 static void add_scavenge_root_nmethod(nmethod* nm); 183 static void drop_scavenge_root_nmethod(nmethod* nm); 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 bool needs_cache_clean() { return _needs_cache_clean; } 218 static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; } 219 static void clear_inline_caches(); // clear all inline caches 220 static void cleanup_inline_caches(); 221 222 // Returns true if an own CodeHeap for the given CodeBlobType is available 223 static bool heap_available(int code_blob_type); 224 225 // Returns the CodeBlobType for the given CompiledMethod 226 static int get_code_blob_type(CompiledMethod* cm) { 227 return get_code_heap(cm)->code_blob_type(); 228 } 229 230 static bool code_blob_type_accepts_compiled(int type) { 231 bool result = type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled; 232 AOT_ONLY( result = result || type == CodeBlobType::AOT; ) 233 return result; 234 } 235 236 static bool code_blob_type_accepts_nmethod(int type) { 237 return type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled; 238 } 239 240 // Returns the CodeBlobType for the given compilation level 241 static int get_code_blob_type(int comp_level) { 242 if (comp_level == CompLevel_none || 243 comp_level == CompLevel_simple || 244 comp_level == CompLevel_full_optimization) { 245 // Non profiled methods 246 return CodeBlobType::MethodNonProfiled; 247 } else if (comp_level == CompLevel_limited_profile || 248 comp_level == CompLevel_full_profile) { 249 // Profiled methods 250 return CodeBlobType::MethodProfiled; 251 } 252 ShouldNotReachHere(); 253 return 0; 254 } 255 256 static void verify_clean_inline_caches(); 257 static void verify_icholder_relocations(); 258 259 // Deoptimization 260 private: 261 static int mark_for_deoptimization(KlassDepChange& changes); 262 #ifdef HOTSWAP 263 static int mark_for_evol_deoptimization(InstanceKlass* dependee); 264 #endif // HOTSWAP 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 #ifdef HOTSWAP 274 // Flushing and deoptimization in case of evolution 275 static void flush_evol_dependents_on(InstanceKlass* dependee); 276 #endif // HOTSWAP 277 // Support for fullspeed debugging 278 static void flush_dependents_on_method(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 }; 288 289 290 // Iterator to iterate over nmethods in the CodeCache. 291 template <class T, class Filter> class CodeBlobIterator : public StackObj { 292 private: 293 CodeBlob* _code_blob; // Current CodeBlob 294 GrowableArrayIterator<CodeHeap*> _heap; 295 GrowableArrayIterator<CodeHeap*> _end; 296 297 public: 298 CodeBlobIterator(T* nm = NULL) { 299 if (Filter::heaps() == NULL) { 300 return; 301 } 302 _heap = Filter::heaps()->begin(); 303 _end = Filter::heaps()->end(); 304 // If set to NULL, initialized by first call to next() 305 _code_blob = (CodeBlob*)nm; 306 if (nm != NULL) { 307 while(!(*_heap)->contains_blob(_code_blob)) { 308 ++_heap; 309 } 310 assert((*_heap)->contains_blob(_code_blob), "match not found"); 311 } 312 } 313 314 // Advance iterator to next blob 315 bool next() { 316 assert_locked_or_safepoint(CodeCache_lock); 317 318 bool result = next_blob(); 319 while (!result && _heap != _end) { 320 // Advance to next code heap of segmented code cache 321 if (++_heap == _end) { 322 break; 323 } 324 result = next_blob(); 325 } 326 327 return result; 328 } 329 330 // Advance iterator to next alive blob 331 bool next_alive() { 332 bool result = next(); 333 while(result && !_code_blob->is_alive()) { 334 result = next(); 335 } 336 return result; 337 } 338 339 bool end() const { return _code_blob == NULL; } 340 T* method() const { return (T*)_code_blob; } 341 342 private: 343 344 // Advance iterator to the next blob in the current code heap 345 bool next_blob() { 346 if (_heap == _end) { 347 return false; 348 } 349 CodeHeap *heap = *_heap; 350 // Get first method CodeBlob 351 if (_code_blob == NULL) { 352 _code_blob = CodeCache::first_blob(heap); 353 if (_code_blob == NULL) { 354 return false; 355 } else if (Filter::apply(_code_blob)) { 356 return true; 357 } 358 } 359 // Search for next method CodeBlob 360 _code_blob = CodeCache::next_blob(heap, _code_blob); 361 while (_code_blob != NULL && !Filter::apply(_code_blob)) { 362 _code_blob = CodeCache::next_blob(heap, _code_blob); 363 } 364 return _code_blob != NULL; 365 } 366 }; 367 368 369 struct CompiledMethodFilter { 370 static bool apply(CodeBlob* cb) { return cb->is_compiled(); } 371 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::compiled_heaps(); } 372 }; 373 374 375 struct NMethodFilter { 376 static bool apply(CodeBlob* cb) { return cb->is_nmethod(); } 377 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::nmethod_heaps(); } 378 }; 379 380 381 typedef CodeBlobIterator<CompiledMethod, CompiledMethodFilter> CompiledMethodIterator; 382 typedef CodeBlobIterator<nmethod, NMethodFilter> NMethodIterator; 383 384 #endif // SHARE_VM_CODE_CODECACHE_HPP