1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
75class ExceptionCache;
76class KlassDepChange;
77class OopClosure;
78class ShenandoahParallelCodeHeapIterator;
79
80class 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(MetadataClosure* f); // 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 IsUnloadingBehaviour* _saved_behaviour;
174
175 public:
176 UnloadingScope(BoolObjectClosure* is_alive);
177 ~UnloadingScope();
178 };
179
180 static void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred);
181 static uint8_t unloading_cycle() { return _unloading_cycle; }
182 static void increment_unloading_cycle();
183 static void release_exception_cache(ExceptionCache* entry);
184 static void purge_exception_caches();
185
186 // Printing/debugging
187 static void print(); // prints summary
188 static void print_internals();
189 static void print_memory_overhead();
190 static void verify(); // verifies the code cache
191 static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN;
192 static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage
193 static void log_state(outputStream* st);
194 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"); }
195 static void report_codemem_full(int code_blob_type, bool print);
196
197 // Dcmd (Diagnostic commands)
198 static void print_codelist(outputStream* st);
199 static void print_layout(outputStream* st);
200
201 // The full limits of the codeCache
202 static address low_bound() { return _low_bound; }
203 static address low_bound(int code_blob_type);
204 static address high_bound() { return _high_bound; }
205 static address high_bound(int code_blob_type);
206
207 // Have to use far call instructions to call this pc.
208 static bool is_far_target(address pc);
209
210 // Profiling
211 static size_t capacity();
212 static size_t unallocated_capacity(int code_blob_type);
213 static size_t unallocated_capacity();
214 static size_t max_capacity();
215
216 static double reverse_free_ratio(int code_blob_type);
217
218 static void clear_inline_caches(); // clear all inline caches
219 static void cleanup_inline_caches(); // clean unloaded/zombie nmethods from inline caches
220
221 // Returns true if an own CodeHeap for the given CodeBlobType is available
222 static bool heap_available(int code_blob_type);
223
224 // Returns the CodeBlobType for the given CompiledMethod
225 static int get_code_blob_type(CompiledMethod* cm) {
226 return get_code_heap(cm)->code_blob_type();
227 }
228
229 static bool code_blob_type_accepts_compiled(int type) {
230 bool result = type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled;
231 AOT_ONLY( result = result || type == CodeBlobType::AOT; )
232 return result;
233 }
234
235 static bool code_blob_type_accepts_nmethod(int type) {
236 return type == CodeBlobType::All || type <= CodeBlobType::MethodProfiled;
237 }
238
239 static bool code_blob_type_accepts_allocable(int type) {
240 return type <= CodeBlobType::All;
241 }
242
243
244 // Returns the CodeBlobType for the given compilation level
245 static int get_code_blob_type(int comp_level) {
246 if (comp_level == CompLevel_none ||
247 comp_level == CompLevel_simple ||
248 comp_level == CompLevel_full_optimization) {
249 // Non profiled methods
250 return CodeBlobType::MethodNonProfiled;
251 } else if (comp_level == CompLevel_limited_profile ||
252 comp_level == CompLevel_full_profile) {
253 // Profiled methods
254 return CodeBlobType::MethodProfiled;
255 }
256 ShouldNotReachHere();
257 return 0;
258 }
259
260 static void verify_clean_inline_caches();
261 static void verify_icholder_relocations();
262
263 // Deoptimization
264 private:
265 static int mark_for_deoptimization(KlassDepChange& changes);
266
267 public:
268 static void mark_all_nmethods_for_deoptimization();
269 static int mark_for_deoptimization(Method* dependee);
270 static void make_marked_nmethods_not_entrant();
271
272 // Flushing and deoptimization
273 static void flush_dependents_on(InstanceKlass* dependee);
274
275 // RedefineClasses support
276 // Flushing and deoptimization in case of evolution
277 static void mark_for_evol_deoptimization(InstanceKlass* dependee);
278 static int mark_dependents_for_evol_deoptimization();
279 static void mark_all_nmethods_for_evol_deoptimization();
280 static void flush_evol_dependents();
281 static void old_nmethods_do(MetadataClosure* f);
282 static void unregister_old_nmethod(CompiledMethod* c);
283
284 // Support for fullspeed debugging
285 static void flush_dependents_on_method(const methodHandle& dependee);
286
287 // tells how many nmethods have dependencies
288 static int number_of_nmethods_with_dependencies();
289
290 static int get_codemem_full_count(int code_blob_type) {
291 CodeHeap* heap = get_code_heap(code_blob_type);
292 return (heap != NULL) ? heap->full_count() : 0;
293 }
294
295 // CodeHeap State Analytics.
296 // interface methods for CodeHeap printing, called by CompileBroker
297 static void aggregate(outputStream *out, size_t granularity);
298 static void discard(outputStream *out);
299 static void print_usedSpace(outputStream *out);
300 static void print_freeSpace(outputStream *out);
301 static void print_count(outputStream *out);
302 static void print_space(outputStream *out);
303 static void print_age(outputStream *out);
304 static void print_names(outputStream *out);
305};
306
307
308// Iterator to iterate over nmethods in the CodeCache.
309template <class T, class Filter> class CodeBlobIterator : public StackObj {
310 public:
311 enum LivenessFilter { all_blobs, only_alive, only_alive_and_not_unloading };
312
313 private:
314 CodeBlob* _code_blob; // Current CodeBlob
315 GrowableArrayIterator<CodeHeap*> _heap;
316 GrowableArrayIterator<CodeHeap*> _end;
317 bool _only_alive;
318 bool _only_not_unloading;
319
320 public:
321 CodeBlobIterator(LivenessFilter filter, T* nm = NULL)
322 : _only_alive(filter == only_alive || filter == only_alive_and_not_unloading),
323 _only_not_unloading(filter == only_alive_and_not_unloading)
324 {
325 if (Filter::heaps() == NULL) {
326 return;
327 }
328 _heap = Filter::heaps()->begin();
329 _end = Filter::heaps()->end();
330 // If set to NULL, initialized by first call to next()
331 _code_blob = (CodeBlob*)nm;
332 if (nm != NULL) {
333 while(!(*_heap)->contains_blob(_code_blob)) {
334 ++_heap;
335 }
336 assert((*_heap)->contains_blob(_code_blob), "match not found");
337 }
338 }
339
340 // Advance iterator to next blob
341 bool next() {
342 assert_locked_or_safepoint(CodeCache_lock);
343
344 for (;;) {
345 // Walk through heaps as required
346 if (!next_blob()) {
347 if (_heap == _end) {
348 return false;
349 }
350 ++_heap;
351 continue;
352 }
353
354 // Filter is_alive as required
355 if (_only_alive && !_code_blob->is_alive()) {
356 continue;
357 }
358
359 // Filter is_unloading as required
360 if (_only_not_unloading) {
361 CompiledMethod* cm = _code_blob->as_compiled_method_or_null();
362 if (cm != NULL && cm->is_unloading()) {
363 continue;
364 }
365 }
366
367 return true;
368 }
369 }
370
371 bool end() const { return _code_blob == NULL; }
372 T* method() const { return (T*)_code_blob; }
373
374private:
375
376 // Advance iterator to the next blob in the current code heap
377 bool next_blob() {
378 if (_heap == _end) {
379 return false;
380 }
381 CodeHeap *heap = *_heap;
382 // Get first method CodeBlob
383 if (_code_blob == NULL) {
384 _code_blob = CodeCache::first_blob(heap);
385 if (_code_blob == NULL) {
386 return false;
387 } else if (Filter::apply(_code_blob)) {
388 return true;
389 }
390 }
391 // Search for next method CodeBlob
392 _code_blob = CodeCache::next_blob(heap, _code_blob);
393 while (_code_blob != NULL && !Filter::apply(_code_blob)) {
394 _code_blob = CodeCache::next_blob(heap, _code_blob);
395 }
396 return _code_blob != NULL;
397 }
398};
399
400
401struct CompiledMethodFilter {
402 static bool apply(CodeBlob* cb) { return cb->is_compiled(); }
403 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::compiled_heaps(); }
404};
405
406
407struct NMethodFilter {
408 static bool apply(CodeBlob* cb) { return cb->is_nmethod(); }
409 static const GrowableArray<CodeHeap*>* heaps() { return CodeCache::nmethod_heaps(); }
410};
411
412typedef CodeBlobIterator<CompiledMethod, CompiledMethodFilter> CompiledMethodIterator;
413typedef CodeBlobIterator<nmethod, NMethodFilter> NMethodIterator;
414
415#endif // SHARE_CODE_CODECACHE_HPP
416