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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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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 // compiled at tier 2 or 3
45 // - Non-Profiled nmethods: nmethods that are not profiled, i.e., those
46 // compiled at tier 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 class HeapConfiguration;
65
66 class CodeCache : AllStatic {
67 friend class VMStructs;
68 private:
69 // Predicate returning true for all method heaps
70 class IsMethodPredicate {
71 public:
72 bool operator()(const CodeHeap* heap) {
73 return heap->accepts(CodeBlobType::MethodProfiled)
74 || heap->accepts(CodeBlobType::MethodNonProfiled);
75 }
76 };
77
78 // CodeHeaps of the cache
79 static GrowableArray<CodeHeap*>* _heaps;
80
81 static address _low_bound; // Lower bound of CodeHeap addresses
82 static address _high_bound; // Upper bound of CodeHeap addresses
83 static int _number_of_blobs; // Total number of CodeBlobs in the cache
84 static int _number_of_adapters; // Total number of Adapters in the cache
85 static int _number_of_nmethods; // Total number of nmethods in the cache
86 static int _number_of_nmethods_with_dependencies; // Total number of nmethods with dependencies
87 static bool _needs_cache_clean; // True if inline caches of the nmethods needs to be flushed
88 static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link()
89 static nmethod* _saved_nmethods; // Linked list of speculatively disconnected nmethods.
90 static int _codemem_full_count; // Number of times a CodeHeap in the cache was full
91
92 // CodeHeap verification
93 static void verify_if_often() PRODUCT_RETURN;
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 // Creates a new heap with the given name and size, containing CodeBlobs of the given type
101 static void add_heap(ReservedSpace rs, const char* name, size_t size_initial, int code_blob_type);
102 static CodeHeap* get_code_heap(int code_blob_type); // Returns the CodeHeap for the given CodeBlobType
103 static bool heap_available(int code_blob_type); // Returns true if a CodeHeap for the given CodeBlobType is available
104 static ReservedCodeSpace reserve_heap_memory(size_t size); // Reserves one continuous chunk of memory for the CodeHeaps
105
106 // Iteration
107 static CodeBlob* first_blob(CodeHeap* heap); // Returns the first CodeBlob on the given CodeHeap
108 static CodeBlob* next_blob(CodeHeap* heap, CodeBlob* cb); // Returns the first alive CodeBlob on the given CodeHeap
109 static CodeBlob* first_alive_blob(CodeHeap* heap); // Returns the next CodeBlob on the given CodeHeap succeeding the given CodeBlob
110 static CodeBlob* next_alive_blob(CodeHeap* heap, CodeBlob* cb); // Returns the next alive CodeBlob on the given CodeHeap succeeding the given CodeBlob
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 verify(); // verifies the code cache
173 static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN;
174 static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage
175 static void log_state(outputStream* st);
176 static const char* get_heap_name(int code_blob_type) { return (heap_available(code_blob_type) ? get_code_heap(code_blob_type)->name() : "Unused"); }
177 static void report_codemem_full(int code_blob_type);
178
179 // The full limits of the codeCache
180 static address low_bound() { return _low_bound; }
181 static address high_bound() { return _high_bound; }
182
183 // Profiling
184 static size_t capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->capacity() : 0; }
185 static size_t capacity();
186 static size_t unallocated_capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->unallocated_capacity() : 0; }
187 static size_t unallocated_capacity();
188 static size_t max_capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->max_capacity() : 0; }
189 static size_t max_capacity();
190
191 static bool is_full(int code_blob_type) { return heap_available(code_blob_type) && (unallocated_capacity(code_blob_type) < CodeCacheMinimumFreeSpace); }
192 static double reverse_free_ratio(int code_blob_type);
193
194 static bool needs_cache_clean() { return _needs_cache_clean; }
195 static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; }
196
197 // Returns the CodeBlobType for nmethods of the given compilation level
198 static int get_code_blob_type(int comp_level) {
199 if (comp_level == CompLevel_none ||
200 comp_level == CompLevel_simple ||
201 comp_level == CompLevel_full_optimization) {
202 // Non profiled methods
203 return CodeBlobType::MethodNonProfiled;
204 } else if (comp_level == CompLevel_limited_profile ||
205 comp_level == CompLevel_full_profile) {
206 // Profiled methods
207 return CodeBlobType::MethodProfiled;
208 }
209 ShouldNotReachHere();
210 return 0;
211 }
212
213 // Deoptimization
214 static int mark_for_deoptimization(DepChange& changes);
215 #ifdef HOTSWAP
216 static int mark_for_evol_deoptimization(instanceKlassHandle dependee);
217 #endif // HOTSWAP
218
219 static void mark_all_nmethods_for_deoptimization();
220 static int mark_for_deoptimization(Method* dependee);
221 static void make_marked_nmethods_zombies();
222 static void make_marked_nmethods_not_entrant();
223
224 // tells how many nmethods have dependencies
225 static int number_of_nmethods_with_dependencies();
226
227 static int get_codemem_full_count() { return _codemem_full_count; }
228 };
229
230 #endif // SHARE_VM_CODE_CODECACHE_HPP