Mon, 24 Dec 2012 11:46:38 -0800
Merge
1 /*
2 * Copyright (c) 1997, 2012, 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 */
25 #ifndef SHARE_VM_CLASSFILE_CLASSLOADER_HPP
26 #define SHARE_VM_CLASSFILE_CLASSLOADER_HPP
28 #include "classfile/classFileParser.hpp"
29 #include "runtime/perfData.hpp"
31 // The VM class loader.
32 #include <sys/stat.h>
35 // Meta-index (optional, to be able to skip opening boot classpath jar files)
36 class MetaIndex: public CHeapObj<mtClass> {
37 private:
38 char** _meta_package_names;
39 int _num_meta_package_names;
40 public:
41 MetaIndex(char** meta_package_names, int num_meta_package_names);
42 ~MetaIndex();
43 bool may_contain(const char* class_name);
44 };
47 // Class path entry (directory or zip file)
49 class ClassPathEntry: public CHeapObj<mtClass> {
50 private:
51 ClassPathEntry* _next;
52 public:
53 // Next entry in class path
54 ClassPathEntry* next() { return _next; }
55 void set_next(ClassPathEntry* next) {
56 // may have unlocked readers, so write atomically.
57 OrderAccess::release_store_ptr(&_next, next);
58 }
59 virtual bool is_jar_file() = 0;
60 virtual const char* name() = 0;
61 virtual bool is_lazy();
62 // Constructor
63 ClassPathEntry();
64 // Attempt to locate file_name through this class path entry.
65 // Returns a class file parsing stream if successfull.
66 virtual ClassFileStream* open_stream(const char* name) = 0;
67 // Debugging
68 NOT_PRODUCT(virtual void compile_the_world(Handle loader, TRAPS) = 0;)
69 NOT_PRODUCT(virtual bool is_rt_jar() = 0;)
70 };
73 class ClassPathDirEntry: public ClassPathEntry {
74 private:
75 char* _dir; // Name of directory
76 public:
77 bool is_jar_file() { return false; }
78 const char* name() { return _dir; }
79 ClassPathDirEntry(char* dir);
80 ClassFileStream* open_stream(const char* name);
81 // Debugging
82 NOT_PRODUCT(void compile_the_world(Handle loader, TRAPS);)
83 NOT_PRODUCT(bool is_rt_jar();)
84 };
87 // Type definitions for zip file and zip file entry
88 typedef void* jzfile;
89 typedef struct {
90 char *name; /* entry name */
91 jlong time; /* modification time */
92 jlong size; /* size of uncompressed data */
93 jlong csize; /* size of compressed data (zero if uncompressed) */
94 jint crc; /* crc of uncompressed data */
95 char *comment; /* optional zip file comment */
96 jbyte *extra; /* optional extra data */
97 jlong pos; /* position of LOC header (if negative) or data */
98 } jzentry;
101 class ClassPathZipEntry: public ClassPathEntry {
102 private:
103 jzfile* _zip; // The zip archive
104 char* _zip_name; // Name of zip archive
105 public:
106 bool is_jar_file() { return true; }
107 const char* name() { return _zip_name; }
108 ClassPathZipEntry(jzfile* zip, const char* zip_name);
109 ~ClassPathZipEntry();
110 ClassFileStream* open_stream(const char* name);
111 void contents_do(void f(const char* name, void* context), void* context);
112 // Debugging
113 NOT_PRODUCT(void compile_the_world(Handle loader, TRAPS);)
114 NOT_PRODUCT(void compile_the_world12(Handle loader, TRAPS);) // JDK 1.2 version
115 NOT_PRODUCT(void compile_the_world13(Handle loader, TRAPS);) // JDK 1.3 version
116 NOT_PRODUCT(bool is_rt_jar();)
117 NOT_PRODUCT(bool is_rt_jar12();)
118 NOT_PRODUCT(bool is_rt_jar13();)
119 };
122 // For lazier loading of boot class path entries
123 class LazyClassPathEntry: public ClassPathEntry {
124 private:
125 char* _path; // dir or file
126 struct stat _st;
127 MetaIndex* _meta_index;
128 volatile ClassPathEntry* _resolved_entry;
129 ClassPathEntry* resolve_entry();
130 public:
131 bool is_jar_file();
132 const char* name() { return _path; }
133 LazyClassPathEntry(char* path, struct stat st);
134 ClassFileStream* open_stream(const char* name);
135 void set_meta_index(MetaIndex* meta_index) { _meta_index = meta_index; }
136 virtual bool is_lazy();
137 // Debugging
138 NOT_PRODUCT(void compile_the_world(Handle loader, TRAPS);)
139 NOT_PRODUCT(bool is_rt_jar();)
140 };
142 class PackageHashtable;
143 class PackageInfo;
144 template <MEMFLAGS F> class HashtableBucket;
146 class ClassLoader: AllStatic {
147 public:
148 enum SomeConstants {
149 package_hash_table_size = 31 // Number of buckets
150 };
151 private:
152 friend class LazyClassPathEntry;
154 // Performance counters
155 static PerfCounter* _perf_accumulated_time;
156 static PerfCounter* _perf_classes_inited;
157 static PerfCounter* _perf_class_init_time;
158 static PerfCounter* _perf_class_init_selftime;
159 static PerfCounter* _perf_classes_verified;
160 static PerfCounter* _perf_class_verify_time;
161 static PerfCounter* _perf_class_verify_selftime;
162 static PerfCounter* _perf_classes_linked;
163 static PerfCounter* _perf_class_link_time;
164 static PerfCounter* _perf_class_link_selftime;
165 static PerfCounter* _perf_class_parse_time;
166 static PerfCounter* _perf_class_parse_selftime;
167 static PerfCounter* _perf_sys_class_lookup_time;
168 static PerfCounter* _perf_shared_classload_time;
169 static PerfCounter* _perf_sys_classload_time;
170 static PerfCounter* _perf_app_classload_time;
171 static PerfCounter* _perf_app_classload_selftime;
172 static PerfCounter* _perf_app_classload_count;
173 static PerfCounter* _perf_define_appclasses;
174 static PerfCounter* _perf_define_appclass_time;
175 static PerfCounter* _perf_define_appclass_selftime;
176 static PerfCounter* _perf_app_classfile_bytes_read;
177 static PerfCounter* _perf_sys_classfile_bytes_read;
179 static PerfCounter* _sync_systemLoaderLockContentionRate;
180 static PerfCounter* _sync_nonSystemLoaderLockContentionRate;
181 static PerfCounter* _sync_JVMFindLoadedClassLockFreeCounter;
182 static PerfCounter* _sync_JVMDefineClassLockFreeCounter;
183 static PerfCounter* _sync_JNIDefineClassLockFreeCounter;
185 static PerfCounter* _unsafe_defineClassCallCounter;
186 static PerfCounter* _isUnsyncloadClass;
187 static PerfCounter* _load_instance_class_failCounter;
189 // First entry in linked list of ClassPathEntry instances
190 static ClassPathEntry* _first_entry;
191 // Last entry in linked list of ClassPathEntry instances
192 static ClassPathEntry* _last_entry;
193 // Hash table used to keep track of loaded packages
194 static PackageHashtable* _package_hash_table;
195 static const char* _shared_archive;
197 // Hash function
198 static unsigned int hash(const char *s, int n);
199 // Returns the package file name corresponding to the specified package
200 // or class name, or null if not found.
201 static PackageInfo* lookup_package(const char *pkgname);
202 // Adds a new package entry for the specified class or package name and
203 // corresponding directory or jar file name.
204 static bool add_package(const char *pkgname, int classpath_index, TRAPS);
206 // Initialization
207 static void setup_meta_index();
208 static void setup_bootstrap_search_path();
209 static void load_zip_library();
210 static void create_class_path_entry(char *path, struct stat st, ClassPathEntry **new_entry, bool lazy);
212 // Canonicalizes path names, so strcmp will work properly. This is mainly
213 // to avoid confusing the zip library
214 static bool get_canonical_path(char* orig, char* out, int len);
215 public:
216 // Used by the kernel jvm.
217 static void update_class_path_entry_list(const char *path,
218 bool check_for_duplicates);
219 static void print_bootclasspath();
221 // Timing
222 static PerfCounter* perf_accumulated_time() { return _perf_accumulated_time; }
223 static PerfCounter* perf_classes_inited() { return _perf_classes_inited; }
224 static PerfCounter* perf_class_init_time() { return _perf_class_init_time; }
225 static PerfCounter* perf_class_init_selftime() { return _perf_class_init_selftime; }
226 static PerfCounter* perf_classes_verified() { return _perf_classes_verified; }
227 static PerfCounter* perf_class_verify_time() { return _perf_class_verify_time; }
228 static PerfCounter* perf_class_verify_selftime() { return _perf_class_verify_selftime; }
229 static PerfCounter* perf_classes_linked() { return _perf_classes_linked; }
230 static PerfCounter* perf_class_link_time() { return _perf_class_link_time; }
231 static PerfCounter* perf_class_link_selftime() { return _perf_class_link_selftime; }
232 static PerfCounter* perf_class_parse_time() { return _perf_class_parse_time; }
233 static PerfCounter* perf_class_parse_selftime() { return _perf_class_parse_selftime; }
234 static PerfCounter* perf_sys_class_lookup_time() { return _perf_sys_class_lookup_time; }
235 static PerfCounter* perf_shared_classload_time() { return _perf_shared_classload_time; }
236 static PerfCounter* perf_sys_classload_time() { return _perf_sys_classload_time; }
237 static PerfCounter* perf_app_classload_time() { return _perf_app_classload_time; }
238 static PerfCounter* perf_app_classload_selftime() { return _perf_app_classload_selftime; }
239 static PerfCounter* perf_app_classload_count() { return _perf_app_classload_count; }
240 static PerfCounter* perf_define_appclasses() { return _perf_define_appclasses; }
241 static PerfCounter* perf_define_appclass_time() { return _perf_define_appclass_time; }
242 static PerfCounter* perf_define_appclass_selftime() { return _perf_define_appclass_selftime; }
243 static PerfCounter* perf_app_classfile_bytes_read() { return _perf_app_classfile_bytes_read; }
244 static PerfCounter* perf_sys_classfile_bytes_read() { return _perf_sys_classfile_bytes_read; }
246 // Record how often system loader lock object is contended
247 static PerfCounter* sync_systemLoaderLockContentionRate() {
248 return _sync_systemLoaderLockContentionRate;
249 }
251 // Record how often non system loader lock object is contended
252 static PerfCounter* sync_nonSystemLoaderLockContentionRate() {
253 return _sync_nonSystemLoaderLockContentionRate;
254 }
256 // Record how many calls to JVM_FindLoadedClass w/o holding a lock
257 static PerfCounter* sync_JVMFindLoadedClassLockFreeCounter() {
258 return _sync_JVMFindLoadedClassLockFreeCounter;
259 }
261 // Record how many calls to JVM_DefineClass w/o holding a lock
262 static PerfCounter* sync_JVMDefineClassLockFreeCounter() {
263 return _sync_JVMDefineClassLockFreeCounter;
264 }
266 // Record how many calls to jni_DefineClass w/o holding a lock
267 static PerfCounter* sync_JNIDefineClassLockFreeCounter() {
268 return _sync_JNIDefineClassLockFreeCounter;
269 }
271 // Record how many calls to Unsafe_DefineClass
272 static PerfCounter* unsafe_defineClassCallCounter() {
273 return _unsafe_defineClassCallCounter;
274 }
276 // Record how many times SystemDictionary::load_instance_class call
277 // fails with linkageError when Unsyncloadclass flag is set.
278 static PerfCounter* load_instance_class_failCounter() {
279 return _load_instance_class_failCounter;
280 }
282 // Load individual .class file
283 static instanceKlassHandle load_classfile(Symbol* h_name, TRAPS);
285 // If the specified package has been loaded by the system, then returns
286 // the name of the directory or ZIP file that the package was loaded from.
287 // Returns null if the package was not loaded.
288 // Note: The specified name can either be the name of a class or package.
289 // If a package name is specified, then it must be "/"-separator and also
290 // end with a trailing "/".
291 static oop get_system_package(const char* name, TRAPS);
293 // Returns an array of Java strings representing all of the currently
294 // loaded system packages.
295 // Note: The package names returned are "/"-separated and end with a
296 // trailing "/".
297 static objArrayOop get_system_packages(TRAPS);
299 // Initialization
300 static void initialize();
301 static void create_package_info_table();
302 static void create_package_info_table(HashtableBucket<mtClass> *t, int length,
303 int number_of_entries);
304 static int compute_Object_vtable();
306 static ClassPathEntry* classpath_entry(int n) {
307 ClassPathEntry* e = ClassLoader::_first_entry;
308 while (--n >= 0) {
309 assert(e != NULL, "Not that many classpath entries.");
310 e = e->next();
311 }
312 return e;
313 }
315 // Sharing dump and restore
316 static void copy_package_info_buckets(char** top, char* end);
317 static void copy_package_info_table(char** top, char* end);
319 // VM monitoring and management support
320 static jlong classloader_time_ms();
321 static jlong class_method_total_size();
322 static jlong class_init_count();
323 static jlong class_init_time_ms();
324 static jlong class_verify_time_ms();
325 static jlong class_link_count();
326 static jlong class_link_time_ms();
328 // indicates if class path already contains a entry (exact match by name)
329 static bool contains_entry(ClassPathEntry* entry);
331 // adds a class path list
332 static void add_to_list(ClassPathEntry* new_entry);
334 // creates a class path zip entry (returns NULL if JAR file cannot be opened)
335 static ClassPathZipEntry* create_class_path_zip_entry(const char *apath);
337 // Debugging
338 static void verify() PRODUCT_RETURN;
340 // Force compilation of all methods in all classes in bootstrap class path (stress test)
341 #ifndef PRODUCT
342 private:
343 static int _compile_the_world_counter;
344 public:
345 static void compile_the_world();
346 static void compile_the_world_in(char* name, Handle loader, TRAPS);
347 static int compile_the_world_counter() { return _compile_the_world_counter; }
348 #endif //PRODUCT
349 };
351 // PerfClassTraceTime is used to measure time for class loading related events.
352 // This class tracks cumulative time and exclusive time for specific event types.
353 // During the execution of one event, other event types (e.g. class loading and
354 // resolution) as well as recursive calls of the same event type could happen.
355 // Only one elapsed timer (cumulative) and one thread-local self timer (exclusive)
356 // (i.e. only one event type) are active at a time even multiple PerfClassTraceTime
357 // instances have been created as multiple events are happening.
358 class PerfClassTraceTime {
359 public:
360 enum {
361 CLASS_LOAD = 0,
362 PARSE_CLASS = 1,
363 CLASS_LINK = 2,
364 CLASS_VERIFY = 3,
365 CLASS_CLINIT = 4,
366 DEFINE_CLASS = 5,
367 EVENT_TYPE_COUNT = 6
368 };
369 protected:
370 // _t tracks time from initialization to destruction of this timer instance
371 // including time for all other event types, and recursive calls of this type.
372 // When a timer is called recursively, the elapsedTimer _t would not be used.
373 elapsedTimer _t;
374 PerfLongCounter* _timep;
375 PerfLongCounter* _selftimep;
376 PerfLongCounter* _eventp;
377 // pointer to thread-local recursion counter and timer array
378 // The thread_local timers track cumulative time for specific event types
379 // exclusive of time for other event types, but including recursive calls
380 // of the same type.
381 int* _recursion_counters;
382 elapsedTimer* _timers;
383 int _event_type;
384 int _prev_active_event;
386 public:
388 inline PerfClassTraceTime(PerfLongCounter* timep, /* counter incremented with inclusive time */
389 PerfLongCounter* selftimep, /* counter incremented with exclusive time */
390 PerfLongCounter* eventp, /* event counter */
391 int* recursion_counters, /* thread-local recursion counter array */
392 elapsedTimer* timers, /* thread-local timer array */
393 int type /* event type */ ) :
394 _timep(timep), _selftimep(selftimep), _eventp(eventp), _recursion_counters(recursion_counters), _timers(timers), _event_type(type) {
395 initialize();
396 }
398 inline PerfClassTraceTime(PerfLongCounter* timep, /* counter incremented with inclusive time */
399 elapsedTimer* timers, /* thread-local timer array */
400 int type /* event type */ ) :
401 _timep(timep), _selftimep(NULL), _eventp(NULL), _recursion_counters(NULL), _timers(timers), _event_type(type) {
402 initialize();
403 }
405 inline void suspend() { _t.stop(); _timers[_event_type].stop(); }
406 inline void resume() { _t.start(); _timers[_event_type].start(); }
408 ~PerfClassTraceTime();
409 void initialize();
410 };
412 #endif // SHARE_VM_CLASSFILE_CLASSLOADER_HPP