Thu, 21 Oct 2010 11:55:10 -0700
6970683: improvements to hs_err output
Reviewed-by: kvn, jrose, dholmes, coleenp
1 /*
2 * Copyright (c) 1997, 2010, 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.
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23 */
25 // The CodeCache implements the code cache for various pieces of generated
26 // code, e.g., compiled java methods, runtime stubs, transition frames, etc.
27 // The entries in the CodeCache are all CodeBlob's.
29 // Implementation:
30 // - Each CodeBlob occupies one chunk of memory.
31 // - Like the offset table in oldspace the zone has at table for
32 // locating a method given a addess of an instruction.
34 class OopClosure;
35 class DepChange;
37 class CodeCache : AllStatic {
38 friend class VMStructs;
39 private:
40 // CodeHeap is malloc()'ed at startup and never deleted during shutdown,
41 // so that the generated assembly code is always there when it's needed.
42 // This may cause memory leak, but is necessary, for now. See 4423824,
43 // 4422213 or 4436291 for details.
44 static CodeHeap * _heap;
45 static int _number_of_blobs;
46 static int _number_of_adapters;
47 static int _number_of_nmethods;
48 static int _number_of_nmethods_with_dependencies;
49 static bool _needs_cache_clean;
50 static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link()
51 static nmethod* _saved_nmethods; // linked via nm->saved_nmethod_look()
53 static void verify_if_often() PRODUCT_RETURN;
55 static void mark_scavenge_root_nmethods() PRODUCT_RETURN;
56 static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN;
58 public:
60 // Initialization
61 static void initialize();
63 // Allocation/administration
64 static CodeBlob* allocate(int size); // allocates a new CodeBlob
65 static void commit(CodeBlob* cb); // called when the allocated CodeBlob has been filled
66 static int alignment_unit(); // guaranteed alignment of all CodeBlobs
67 static int alignment_offset(); // guaranteed offset of first CodeBlob byte within alignment unit (i.e., allocation header)
68 static void free(CodeBlob* cb); // frees a CodeBlob
69 static void flush(); // flushes all CodeBlobs
70 static bool contains(void *p); // returns whether p is included
71 static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs
72 static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs
73 static void nmethods_do(void f(nmethod* nm)); // iterates over all nmethods
75 // Lookup
76 static CodeBlob* find_blob(void* start);
77 static nmethod* find_nmethod(void* start);
79 // Lookup that does not fail if you lookup a zombie method (if you call this, be sure to know
80 // what you are doing)
81 static CodeBlob* find_blob_unsafe(void* start) {
82 CodeBlob* result = (CodeBlob*)_heap->find_start(start);
83 // this assert is too strong because the heap code will return the
84 // heapblock containing start. That block can often be larger than
85 // the codeBlob itself. If you look up an address that is within
86 // the heapblock but not in the codeBlob you will assert.
87 //
88 // Most things will not lookup such bad addresses. However
89 // AsyncGetCallTrace can see intermediate frames and get that kind
90 // of invalid address and so can a developer using hsfind.
91 //
92 // The more correct answer is to return NULL if blob_contains() returns
93 // false.
94 // assert(result == NULL || result->blob_contains((address)start), "found wrong CodeBlob");
96 if (result != NULL && !result->blob_contains((address)start)) {
97 result = NULL;
98 }
99 return result;
100 }
102 // Iteration
103 static CodeBlob* first();
104 static CodeBlob* next (CodeBlob* cb);
105 static CodeBlob* alive(CodeBlob *cb);
106 static nmethod* alive_nmethod(CodeBlob *cb);
107 static nmethod* first_nmethod();
108 static nmethod* next_nmethod (CodeBlob* cb);
109 static int nof_blobs() { return _number_of_blobs; }
110 static int nof_adapters() { return _number_of_adapters; }
111 static int nof_nmethods() { return _number_of_nmethods; }
113 // GC support
114 static void gc_epilogue();
115 static void gc_prologue();
116 // If "unloading_occurred" is true, then unloads (i.e., breaks root links
117 // to) any unmarked codeBlobs in the cache. Sets "marked_for_unloading"
118 // to "true" iff some code got unloaded.
119 static void do_unloading(BoolObjectClosure* is_alive,
120 OopClosure* keep_alive,
121 bool unloading_occurred);
122 static void oops_do(OopClosure* f) {
123 CodeBlobToOopClosure oopc(f, /*do_marking=*/ false);
124 blobs_do(&oopc);
125 }
126 static void asserted_non_scavengable_nmethods_do(CodeBlobClosure* f = NULL) PRODUCT_RETURN;
127 static void scavenge_root_nmethods_do(CodeBlobClosure* f);
129 static nmethod* scavenge_root_nmethods() { return _scavenge_root_nmethods; }
130 static void set_scavenge_root_nmethods(nmethod* nm) { _scavenge_root_nmethods = nm; }
131 static void add_scavenge_root_nmethod(nmethod* nm);
132 static void drop_scavenge_root_nmethod(nmethod* nm);
133 static void prune_scavenge_root_nmethods();
135 // Printing/debugging
136 static void print() PRODUCT_RETURN; // prints summary
137 static void print_internals();
138 static void verify(); // verifies the code cache
139 static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN;
140 static void print_bounds(outputStream* st); // Prints a summary of the bounds of the code cache
142 // The full limits of the codeCache
143 static address low_bound() { return (address) _heap->low_boundary(); }
144 static address high_bound() { return (address) _heap->high_boundary(); }
146 // Profiling
147 static address first_address(); // first address used for CodeBlobs
148 static address last_address(); // last address used for CodeBlobs
149 static size_t capacity() { return _heap->capacity(); }
150 static size_t max_capacity() { return _heap->max_capacity(); }
151 static size_t unallocated_capacity() { return _heap->unallocated_capacity(); }
152 static bool needs_flushing() { return unallocated_capacity() < CodeCacheFlushingMinimumFreeSpace; }
154 static bool needs_cache_clean() { return _needs_cache_clean; }
155 static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; }
156 static void clear_inline_caches(); // clear all inline caches
158 static nmethod* find_and_remove_saved_code(methodOop m);
159 static void remove_saved_code(nmethod* nm);
160 static void speculatively_disconnect(nmethod* nm);
162 // Deoptimization
163 static int mark_for_deoptimization(DepChange& changes);
164 #ifdef HOTSWAP
165 static int mark_for_evol_deoptimization(instanceKlassHandle dependee);
166 #endif // HOTSWAP
168 static void mark_all_nmethods_for_deoptimization();
169 static int mark_for_deoptimization(methodOop dependee);
170 static void make_marked_nmethods_zombies();
171 static void make_marked_nmethods_not_entrant();
173 // tells how many nmethods have dependencies
174 static int number_of_nmethods_with_dependencies();
175 };