1 /* 2 * Copyright (c) 1997, 2013, 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 "memory/allocation.hpp" 30 #include "memory/heap.hpp" 31 #include "oops/instanceKlass.hpp" 32 #include "oops/oopsHierarchy.hpp" 33 34 // The CodeCache implements the code cache for various pieces of generated 35 // code, e.g., compiled java methods, runtime stubs, transition frames, etc. 36 // The entries in the CodeCache are all CodeBlob's. 37 38 // -- Implementation -- 39 // The CodeCache consists of multiple CodeHeaps, each of which contains 40 // CodeBlobs of a specific CodeBlobType. Currently heaps for the following 41 // types are available: 42 // - Non-methods: Non-methods like Buffers, Adapters and Runtime Stubs 43 // - Profiled nmethods: nmethods that are profiled, i.e., those 44 // executed at level 2 or 3 45 // - Non-Profiled nmethods: nmethods that are not profiled, i.e., those 46 // executed at level 1 or 4 and native methods 47 // 48 // Depending on the availability of compilers and TieredCompilation being 49 // deactivated there may be fewer heaps. The size of the heaps depends on 50 // the values of ReservedCodeCacheSize, NonProfiledCodeHeapSize and 51 // ProfiledCodeHeapSize (see CodeCache::initialize_heaps for details). 52 // 53 // All methods of the CodeCache accepting a CodeBlobType only apply to 54 // CodeBlobs of the given type. For example, iteration over the 55 // CodeBlobs of a specific type can be done by using CodeCache::first_blob 56 // and CodeCache::next_blob and providing the corresponding CodeBlobType. 57 // 58 // IMPORTANT: If you add new CodeHeaps to the code cache or change the 59 // existing ones, make sure to adapt the dtrace scripts (jhelper.d) for 60 // Solaris and BSD. 61 62 class OopClosure; 63 class DepChange; 64 65 class CodeCache : AllStatic { 66 friend class VMStructs; 67 private: 68 // Predicate returning true for all method heaps 69 class IsMethodPredicate { 70 public: 71 bool operator()(const CodeHeap* heap) { 72 return heap->accepts(CodeBlobType::MethodProfiled) 73 || heap->accepts(CodeBlobType::MethodNonProfiled); 74 } 75 }; 76 77 // CodeHeaps of the cache 78 static GrowableArray<CodeHeap*>* _heaps; 79 80 static address _low_bound; // Lower bound of CodeHeap addresses 81 static address _high_bound; // Upper bound of CodeHeap addresses 82 static int _number_of_blobs; // Total number of CodeBlobs in the cache 83 static int _number_of_adapters; // Total number of Adapters in the cache 84 static int _number_of_nmethods; // Total number of nmethods in the cache 85 static int _number_of_nmethods_with_dependencies; // Total number of nmethods with dependencies 86 static bool _needs_cache_clean; // True if inline caches of the nmethods needs to be flushed 87 static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link() 88 static nmethod* _saved_nmethods; // Linked list of speculatively disconnected nmethods. 89 static int _codemem_full_count; // Number of times a CodeHeap in the cache was full 90 91 static void mark_scavenge_root_nmethods() PRODUCT_RETURN; 92 static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN; 93 94 // CodeHeap management 95 static void initialize_heaps(); // Initializes the CodeHeaps 96 // Creates a new heap with the given name and size, containing CodeBlobs of the given type 97 static void add_heap(ReservedSpace rs, const char* name, size_t size_initial, int code_blob_type); 98 static CodeHeap* get_code_heap(int code_blob_type); // Returns the CodeHeap for the given CodeBlobType 99 static bool heap_available(int code_blob_type); // Returns true if a CodeHeap for the given CodeBlobType is available 100 static ReservedCodeSpace reserve_heap_memory(size_t size); // Reserves one continuous chunk of memory for the CodeHeaps 101 102 // Iteration 103 static CodeBlob* first_blob(CodeHeap* heap); // Returns the first CodeBlob on the given CodeHeap 104 static CodeBlob* next_blob(CodeHeap* heap, CodeBlob* cb); // Returns the first alive CodeBlob on the given CodeHeap 105 static CodeBlob* first_alive_blob(CodeHeap* heap); // Returns the next CodeBlob on the given CodeHeap succeeding the given CodeBlob 106 static CodeBlob* next_alive_blob(CodeHeap* heap, CodeBlob* cb); // Returns the next alive CodeBlob on the given CodeHeap succeeding the given CodeBlob 107 108 static size_t bytes_allocated_in_freelists(); 109 static int allocated_segments(); 110 static size_t freelists_length(); 111 112 public: 113 // Initialization 114 static void initialize(); 115 116 // Allocation/administration 117 static CodeBlob* allocate(int size, int code_blob_type, bool is_critical = false); // allocates a new CodeBlob 118 static void commit(CodeBlob* cb); // called when the allocated CodeBlob has been filled 119 static int alignment_unit(); // guaranteed alignment of all CodeBlobs 120 static int alignment_offset(); // guaranteed offset of first CodeBlob byte within alignment unit (i.e., allocation header) 121 static void free(CodeBlob* cb, int code_blob_type); // frees a CodeBlob 122 static bool contains(void *p); // returns whether p is included 123 static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs 124 static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs 125 static void nmethods_do(void f(nmethod* nm)); // iterates over all nmethods 126 static void alive_nmethods_do(void f(nmethod* nm)); // iterates over all alive nmethods 127 128 // Lookup 129 static CodeBlob* find_blob(void* start); // Returns the CodeBlob containing the given address 130 static CodeBlob* find_blob_unsafe(void* start); // Same as find_blob but does not fail if looking up a zombie method 131 static nmethod* find_nmethod(void* start); // Returns the nmethod containing the given address 132 static bool contains_nmethod(nmethod* nm); // Returns true if the CodeCache contains the given nmethod 133 134 // Iteration 135 // Returns the first CodeBlob of the given type 136 static CodeBlob* first_blob(int code_blob_type) { return first_blob(get_code_heap(code_blob_type)); } 137 // Returns the first alive CodeBlob of the given type 138 static CodeBlob* first_alive_blob(int code_blob_type) { return first_alive_blob(get_code_heap(code_blob_type)); } 139 // Returns the next CodeBlob of the given type succeeding the given CodeBlob 140 static CodeBlob* next_blob(CodeBlob* cb, int code_blob_type) { return next_blob(get_code_heap(code_blob_type), cb); } 141 // Returns the next alive CodeBlob of the given type succeeding the given CodeBlob 142 static CodeBlob* next_alive_blob(CodeBlob* cb, int code_blob_type) { return next_alive_blob(get_code_heap(code_blob_type), cb); } 143 144 static int nof_blobs() { return _number_of_blobs; } // Returns the total number of CodeBlobs in the cache 145 static int nof_adapters() { return _number_of_adapters; } // Returns the total number of Adapters in the cache 146 static int nof_nmethods() { return _number_of_nmethods; } // Returns the total number of nmethods in the cache 147 148 // GC support 149 static void gc_epilogue(); 150 static void gc_prologue(); 151 static void verify_oops(); 152 // If "unloading_occurred" is true, then unloads (i.e., breaks root links 153 // to) any unmarked codeBlobs in the cache. Sets "marked_for_unloading" 154 // to "true" iff some code got unloaded. 155 static void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred); 156 static void oops_do(OopClosure* f) { 157 CodeBlobToOopClosure oopc(f, /*do_marking=*/ false); 158 blobs_do(&oopc); 159 } 160 static void asserted_non_scavengable_nmethods_do(CodeBlobClosure* f = NULL) PRODUCT_RETURN; 161 static void scavenge_root_nmethods_do(CodeBlobClosure* f); 162 163 static nmethod* scavenge_root_nmethods() { return _scavenge_root_nmethods; } 164 static void set_scavenge_root_nmethods(nmethod* nm) { _scavenge_root_nmethods = nm; } 165 static void add_scavenge_root_nmethod(nmethod* nm); 166 static void drop_scavenge_root_nmethod(nmethod* nm); 167 static void prune_scavenge_root_nmethods(); 168 169 // Printing/debugging 170 static void print(); // prints summary 171 static void print_internals(); 172 static void print_memory_overhead(); 173 static void verify(); // verifies the code cache 174 static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN; 175 static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage 176 static void log_state(outputStream* st); 177 static const char* get_heap_name(int code_blob_type) { return (heap_available(code_blob_type) ? get_code_heap(code_blob_type)->name() : "Unused"); } 178 static void report_codemem_full(int code_blob_type, bool print); 179 180 // The full limits of the codeCache 181 static address low_bound() { return _low_bound; } 182 static address high_bound() { return _high_bound; } 183 184 // Profiling 185 static size_t capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->capacity() : 0; } 186 static size_t capacity(); 187 static size_t unallocated_capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->unallocated_capacity() : 0; } 188 static size_t unallocated_capacity(); 189 static size_t max_capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->max_capacity() : 0; } 190 static size_t max_capacity(); 191 192 static bool is_full(int code_blob_type) { return heap_available(code_blob_type) && (unallocated_capacity(code_blob_type) < CodeCacheMinimumFreeSpace); } 193 static double reverse_free_ratio(int code_blob_type); 194 195 static bool needs_cache_clean() { return _needs_cache_clean; } 196 static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; } 197 static void clear_inline_caches(); // clear all inline caches 198 199 // Returns the CodeBlobType for nmethods of the given compilation level 200 static int get_code_blob_type(int comp_level) { 201 if (comp_level == CompLevel_none || 202 comp_level == CompLevel_simple || 203 comp_level == CompLevel_full_optimization) { 204 // Non profiled methods 205 return CodeBlobType::MethodNonProfiled; 206 } else if (comp_level == CompLevel_limited_profile || 207 comp_level == CompLevel_full_profile) { 208 // Profiled methods 209 return CodeBlobType::MethodProfiled; 210 } 211 ShouldNotReachHere(); 212 return 0; 213 } 214 215 // Deoptimization 216 static int mark_for_deoptimization(DepChange& changes); 217 #ifdef HOTSWAP 218 static int mark_for_evol_deoptimization(instanceKlassHandle dependee); 219 #endif // HOTSWAP 220 221 static void mark_all_nmethods_for_deoptimization(); 222 static int mark_for_deoptimization(Method* dependee); 223 static void make_marked_nmethods_zombies(); 224 static void make_marked_nmethods_not_entrant(); 225 226 // tells how many nmethods have dependencies 227 static int number_of_nmethods_with_dependencies(); 228 229 static int get_codemem_full_count() { return _codemem_full_count; } 230 }; 231 232 #endif // SHARE_VM_CODE_CODECACHE_HPP