1 /*
2 * Copyright (c) 2003, 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.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvmtifiles/jvmtiEnv.hpp"
27 #include "prims/jvmtiExport.hpp"
28 #include "prims/jvmtiManageCapabilities.hpp"
29 static const jint CAPA_SIZE = (JVMTI_INTERNAL_CAPABILITY_COUNT + 7) / 8;
30
31 // capabilities which are always potentially available
32 jvmtiCapabilities JvmtiManageCapabilities::always_capabilities;
33
34 // capabilities which are potentially available during OnLoad
35 jvmtiCapabilities JvmtiManageCapabilities::onload_capabilities;
36
37 // capabilities which are always potentially available
38 // but to only one environment
39 jvmtiCapabilities JvmtiManageCapabilities::always_solo_capabilities;
40
41 // capabilities which are potentially available during OnLoad
42 // but to only one environment
43 jvmtiCapabilities JvmtiManageCapabilities::onload_solo_capabilities;
44
45 // remaining capabilities which are always potentially available
46 // but to only one environment
47 jvmtiCapabilities JvmtiManageCapabilities::always_solo_remaining_capabilities;
48
49 // remaining capabilities which are potentially available during OnLoad
50 // but to only one environment
51 jvmtiCapabilities JvmtiManageCapabilities::onload_solo_remaining_capabilities;
52
53 // all capabilities ever acquired
54 jvmtiCapabilities JvmtiManageCapabilities::acquired_capabilities;
55
56 void JvmtiManageCapabilities::initialize() {
57 always_capabilities = init_always_capabilities();
58 if (JvmtiEnv::get_phase() != JVMTI_PHASE_ONLOAD) {
59 recompute_always_capabilities();
60 }
61 onload_capabilities = init_onload_capabilities();
62 always_solo_capabilities = init_always_solo_capabilities();
63 onload_solo_capabilities = init_onload_solo_capabilities();
64 always_solo_remaining_capabilities = init_always_solo_capabilities();
65 onload_solo_remaining_capabilities = init_onload_solo_capabilities();
66 memset(&acquired_capabilities, 0, sizeof(acquired_capabilities));
67 }
68
69 // if the capability sets are initialized in the onload phase then
70 // it happens before class data sharing (CDS) is initialized. If it
71 // turns out that CDS gets disabled then we must adjust the always
72 // capabilities. To ensure a consistent view of the capabililties
73 // anything we add here should already be in the onload set.
74 void JvmtiManageCapabilities::recompute_always_capabilities() {
75 if (!UseSharedSpaces) {
76 jvmtiCapabilities jc = always_capabilities;
77 jc.can_generate_all_class_hook_events = 1;
78 always_capabilities = jc;
79 }
80 }
81
82
83 // corresponding init functions
84 jvmtiCapabilities JvmtiManageCapabilities::init_always_capabilities() {
85 jvmtiCapabilities jc;
86
87 memset(&jc, 0, sizeof(jc));
88 jc.can_get_bytecodes = 1;
89 jc.can_signal_thread = 1;
90 jc.can_get_source_file_name = 1;
91 jc.can_get_line_numbers = 1;
92 jc.can_get_synthetic_attribute = 1;
93 jc.can_get_monitor_info = 1;
94 jc.can_get_constant_pool = 1;
95 jc.can_generate_monitor_events = 1;
96 jc.can_generate_garbage_collection_events = 1;
97 jc.can_generate_compiled_method_load_events = 1;
98 jc.can_generate_native_method_bind_events = 1;
99 jc.can_generate_vm_object_alloc_events = 1;
100 if (os::is_thread_cpu_time_supported()) {
101 jc.can_get_current_thread_cpu_time = 1;
102 jc.can_get_thread_cpu_time = 1;
103 }
104 jc.can_redefine_classes = 1;
105 jc.can_redefine_any_class = 1;
106 jc.can_retransform_classes = 1;
107 jc.can_retransform_any_class = 1;
108 jc.can_set_native_method_prefix = 1;
109 jc.can_tag_objects = 1;
110 jc.can_generate_object_free_events = 1;
111 jc.can_generate_resource_exhaustion_heap_events = 1;
112 jc.can_generate_resource_exhaustion_threads_events = 1;
113 return jc;
114 }
115
116 jvmtiCapabilities JvmtiManageCapabilities::init_onload_capabilities() {
117 jvmtiCapabilities jc;
118
119 memset(&jc, 0, sizeof(jc));
120 #ifndef CC_INTERP
121 jc.can_pop_frame = 1;
122 jc.can_force_early_return = 1;
123 #endif // !CC_INTERP
124 jc.can_get_source_debug_extension = 1;
125 jc.can_access_local_variables = 1;
126 jc.can_maintain_original_method_order = 1;
127 jc.can_generate_all_class_hook_events = 1;
128 jc.can_generate_single_step_events = 1;
129 jc.can_generate_exception_events = 1;
130 jc.can_generate_frame_pop_events = 1;
131 jc.can_generate_method_entry_events = 1;
132 jc.can_generate_method_exit_events = 1;
133 jc.can_get_owned_monitor_info = 1;
134 jc.can_get_owned_monitor_stack_depth_info = 1;
135 jc.can_get_current_contended_monitor = 1;
136 // jc.can_get_monitor_info = 1;
137 jc.can_tag_objects = 1; // TODO: this should have been removed
138 jc.can_generate_object_free_events = 1; // TODO: this should have been removed
139 return jc;
140 }
141
142
143 jvmtiCapabilities JvmtiManageCapabilities::init_always_solo_capabilities() {
144 jvmtiCapabilities jc;
145
146 memset(&jc, 0, sizeof(jc));
147 jc.can_suspend = 1;
148 return jc;
149 }
150
151
152 jvmtiCapabilities JvmtiManageCapabilities::init_onload_solo_capabilities() {
153 jvmtiCapabilities jc;
154
155 memset(&jc, 0, sizeof(jc));
156 jc.can_generate_field_modification_events = 1;
157 jc.can_generate_field_access_events = 1;
158 jc.can_generate_breakpoint_events = 1;
159 return jc;
160 }
161
162
163 jvmtiCapabilities *JvmtiManageCapabilities::either(const jvmtiCapabilities *a, const jvmtiCapabilities *b,
164 jvmtiCapabilities *result) {
165 char *ap = (char *)a;
166 char *bp = (char *)b;
167 char *resultp = (char *)result;
168
169 for (int i = 0; i < CAPA_SIZE; ++i) {
170 *resultp++ = *ap++ | *bp++;
171 }
172
173 return result;
174 }
175
176
177 jvmtiCapabilities *JvmtiManageCapabilities::both(const jvmtiCapabilities *a, const jvmtiCapabilities *b,
178 jvmtiCapabilities *result) {
179 char *ap = (char *)a;
180 char *bp = (char *)b;
181 char *resultp = (char *)result;
182
183 for (int i = 0; i < CAPA_SIZE; ++i) {
184 *resultp++ = *ap++ & *bp++;
185 }
186
187 return result;
188 }
189
190
191 jvmtiCapabilities *JvmtiManageCapabilities::exclude(const jvmtiCapabilities *a, const jvmtiCapabilities *b,
192 jvmtiCapabilities *result) {
193 char *ap = (char *)a;
194 char *bp = (char *)b;
195 char *resultp = (char *)result;
196
197 for (int i = 0; i < CAPA_SIZE; ++i) {
198 *resultp++ = *ap++ & ~*bp++;
199 }
200
201 return result;
202 }
203
204
205 bool JvmtiManageCapabilities::has_some(const jvmtiCapabilities *a) {
206 char *ap = (char *)a;
207
208 for (int i = 0; i < CAPA_SIZE; ++i) {
209 if (*ap++ != 0) {
210 return true;
211 }
212 }
213
214 return false;
215 }
216
217
218 void JvmtiManageCapabilities::copy_capabilities(const jvmtiCapabilities *from, jvmtiCapabilities *to) {
219 char *ap = (char *)from;
220 char *resultp = (char *)to;
221
222 for (int i = 0; i < CAPA_SIZE; ++i) {
223 *resultp++ = *ap++;
224 }
225 }
226
227
228 void JvmtiManageCapabilities::get_potential_capabilities(const jvmtiCapabilities *current,
229 const jvmtiCapabilities *prohibited,
230 jvmtiCapabilities *result) {
231 // exclude prohibited capabilities, must be before adding current
232 exclude(&always_capabilities, prohibited, result);
233
234 // must include current since it may possess solo capabilities and now prohibited
235 either(result, current, result);
236
237 // add other remaining
238 either(result, &always_solo_remaining_capabilities, result);
239
240 // if this is during OnLoad more capabilities are available
241 if (JvmtiEnv::get_phase() == JVMTI_PHASE_ONLOAD) {
242 either(result, &onload_capabilities, result);
243 either(result, &onload_solo_remaining_capabilities, result);
244 }
245 }
246
247 jvmtiError JvmtiManageCapabilities::add_capabilities(const jvmtiCapabilities *current,
248 const jvmtiCapabilities *prohibited,
249 const jvmtiCapabilities *desired,
250 jvmtiCapabilities *result) {
251 // check that the capabilities being added are potential capabilities
252 jvmtiCapabilities temp;
253 get_potential_capabilities(current, prohibited, &temp);
254 if (has_some(exclude(desired, &temp, &temp))) {
255 return JVMTI_ERROR_NOT_AVAILABLE;
256 }
257
258 // add to the set of ever acquired capabilities
259 either(&acquired_capabilities, desired, &acquired_capabilities);
260
261 // onload capabilities that got added are now permanent - so, also remove from onload
262 both(&onload_capabilities, desired, &temp);
263 either(&always_capabilities, &temp, &always_capabilities);
264 exclude(&onload_capabilities, &temp, &onload_capabilities);
265
266 // same for solo capabilities (transferred capabilities in the remaining sets handled as part of standard grab - below)
267 both(&onload_solo_capabilities, desired, &temp);
268 either(&always_solo_capabilities, &temp, &always_solo_capabilities);
269 exclude(&onload_solo_capabilities, &temp, &onload_solo_capabilities);
270
271 // remove solo capabilities that are now taken
272 exclude(&always_solo_remaining_capabilities, desired, &always_solo_remaining_capabilities);
273 exclude(&onload_solo_remaining_capabilities, desired, &onload_solo_remaining_capabilities);
274
275 // return the result
276 either(current, desired, result);
277
278 update();
279
280 return JVMTI_ERROR_NONE;
281 }
282
283
284 void JvmtiManageCapabilities::relinquish_capabilities(const jvmtiCapabilities *current,
285 const jvmtiCapabilities *unwanted,
286 jvmtiCapabilities *result) {
287 jvmtiCapabilities to_trash;
288 jvmtiCapabilities temp;
289
290 // can't give up what you don't have
291 both(current, unwanted, &to_trash);
292
293 // restore solo capabilities but only those that belong
294 either(&always_solo_remaining_capabilities, both(&always_solo_capabilities, &to_trash, &temp),
295 &always_solo_remaining_capabilities);
296 either(&onload_solo_remaining_capabilities, both(&onload_solo_capabilities, &to_trash, &temp),
297 &onload_solo_remaining_capabilities);
298
299 update();
300
301 // return the result
302 exclude(current, unwanted, result);
303 }
304
305
306 void JvmtiManageCapabilities::update() {
307 jvmtiCapabilities avail;
308
309 // all capabilities
310 either(&always_capabilities, &always_solo_capabilities, &avail);
311
312 bool interp_events =
313 avail.can_generate_field_access_events ||
314 avail.can_generate_field_modification_events ||
315 avail.can_generate_single_step_events ||
316 avail.can_generate_frame_pop_events ||
317 avail.can_generate_method_entry_events ||
318 avail.can_generate_method_exit_events;
319 bool enter_all_methods =
320 interp_events ||
321 avail.can_generate_breakpoint_events;
322 UseFastEmptyMethods = !enter_all_methods;
323 UseFastAccessorMethods = !enter_all_methods;
324
325 if (avail.can_generate_breakpoint_events) {
326 RewriteFrequentPairs = false;
327 }
328
329 // If can_redefine_classes is enabled in the onload phase then we know that the
330 // dependency information recorded by the compiler is complete.
331 if ((avail.can_redefine_classes || avail.can_retransform_classes) &&
332 JvmtiEnv::get_phase() == JVMTI_PHASE_ONLOAD) {
333 JvmtiExport::set_all_dependencies_are_recorded(true);
334 }
335
336 JvmtiExport::set_can_get_source_debug_extension(avail.can_get_source_debug_extension);
337 JvmtiExport::set_can_maintain_original_method_order(avail.can_maintain_original_method_order);
338 JvmtiExport::set_can_post_interpreter_events(interp_events);
339 JvmtiExport::set_can_hotswap_or_post_breakpoint(
340 avail.can_generate_breakpoint_events ||
341 avail.can_redefine_classes ||
342 avail.can_retransform_classes);
343 JvmtiExport::set_can_modify_any_class(
344 avail.can_generate_breakpoint_events ||
345 avail.can_generate_all_class_hook_events);
346 JvmtiExport::set_can_walk_any_space(
347 avail.can_tag_objects); // disable sharing in onload phase
348 // This controls whether the compilers keep extra locals live to
349 // improve the debugging experience so only set them if the selected
350 // capabilities look like a debugger.
351 JvmtiExport::set_can_access_local_variables(
352 avail.can_access_local_variables ||
353 avail.can_generate_breakpoint_events ||
354 avail.can_generate_frame_pop_events);
355 JvmtiExport::set_can_post_on_exceptions(
356 avail.can_generate_exception_events ||
357 avail.can_generate_frame_pop_events ||
358 avail.can_generate_method_exit_events);
359 JvmtiExport::set_can_post_breakpoint(avail.can_generate_breakpoint_events);
360 JvmtiExport::set_can_post_field_access(avail.can_generate_field_access_events);
361 JvmtiExport::set_can_post_field_modification(avail.can_generate_field_modification_events);
362 JvmtiExport::set_can_post_method_entry(avail.can_generate_method_entry_events);
363 JvmtiExport::set_can_post_method_exit(avail.can_generate_method_exit_events ||
364 avail.can_generate_frame_pop_events);
365 JvmtiExport::set_can_pop_frame(avail.can_pop_frame);
366 JvmtiExport::set_can_force_early_return(avail.can_force_early_return);
367 JvmtiExport::set_should_clean_up_heap_objects(avail.can_generate_breakpoint_events);
368 }
369
370 #ifndef PRODUCT
371
372 void JvmtiManageCapabilities:: print(const jvmtiCapabilities* cap) {
373 tty->print_cr("----- capabilities -----");
374 if (cap->can_tag_objects)
375 tty->print_cr("can_tag_objects");
376 if (cap->can_generate_field_modification_events)
377 tty->print_cr("can_generate_field_modification_events");
378 if (cap->can_generate_field_access_events)
379 tty->print_cr("can_generate_field_access_events");
380 if (cap->can_get_bytecodes)
381 tty->print_cr("can_get_bytecodes");
382 if (cap->can_get_synthetic_attribute)
383 tty->print_cr("can_get_synthetic_attribute");
384 if (cap->can_get_owned_monitor_info)
385 tty->print_cr("can_get_owned_monitor_info");
386 if (cap->can_get_current_contended_monitor)
387 tty->print_cr("can_get_current_contended_monitor");
388 if (cap->can_get_monitor_info)
389 tty->print_cr("can_get_monitor_info");
390 if (cap->can_get_constant_pool)
391 tty->print_cr("can_get_constant_pool");
392 if (cap->can_pop_frame)
393 tty->print_cr("can_pop_frame");
394 if (cap->can_force_early_return)
395 tty->print_cr("can_force_early_return");
396 if (cap->can_redefine_classes)
397 tty->print_cr("can_redefine_classes");
398 if (cap->can_retransform_classes)
399 tty->print_cr("can_retransform_classes");
400 if (cap->can_signal_thread)
401 tty->print_cr("can_signal_thread");
402 if (cap->can_get_source_file_name)
403 tty->print_cr("can_get_source_file_name");
404 if (cap->can_get_line_numbers)
405 tty->print_cr("can_get_line_numbers");
406 if (cap->can_get_source_debug_extension)
407 tty->print_cr("can_get_source_debug_extension");
408 if (cap->can_access_local_variables)
409 tty->print_cr("can_access_local_variables");
410 if (cap->can_maintain_original_method_order)
411 tty->print_cr("can_maintain_original_method_order");
412 if (cap->can_generate_single_step_events)
413 tty->print_cr("can_generate_single_step_events");
414 if (cap->can_generate_exception_events)
415 tty->print_cr("can_generate_exception_events");
416 if (cap->can_generate_frame_pop_events)
417 tty->print_cr("can_generate_frame_pop_events");
418 if (cap->can_generate_breakpoint_events)
419 tty->print_cr("can_generate_breakpoint_events");
420 if (cap->can_suspend)
421 tty->print_cr("can_suspend");
422 if (cap->can_redefine_any_class )
423 tty->print_cr("can_redefine_any_class");
424 if (cap->can_retransform_any_class )
425 tty->print_cr("can_retransform_any_class");
426 if (cap->can_get_current_thread_cpu_time)
427 tty->print_cr("can_get_current_thread_cpu_time");
428 if (cap->can_get_thread_cpu_time)
429 tty->print_cr("can_get_thread_cpu_time");
430 if (cap->can_generate_method_entry_events)
431 tty->print_cr("can_generate_method_entry_events");
432 if (cap->can_generate_method_exit_events)
433 tty->print_cr("can_generate_method_exit_events");
434 if (cap->can_generate_all_class_hook_events)
435 tty->print_cr("can_generate_all_class_hook_events");
436 if (cap->can_generate_compiled_method_load_events)
437 tty->print_cr("can_generate_compiled_method_load_events");
438 if (cap->can_generate_monitor_events)
439 tty->print_cr("can_generate_monitor_events");
440 if (cap->can_generate_vm_object_alloc_events)
441 tty->print_cr("can_generate_vm_object_alloc_events");
442 if (cap->can_generate_native_method_bind_events)
443 tty->print_cr("can_generate_native_method_bind_events");
444 if (cap->can_generate_garbage_collection_events)
445 tty->print_cr("can_generate_garbage_collection_events");
446 if (cap->can_generate_object_free_events)
447 tty->print_cr("can_generate_object_free_events");
448 if (cap->can_generate_resource_exhaustion_heap_events)
449 tty->print_cr("can_generate_resource_exhaustion_heap_events");
450 if (cap->can_generate_resource_exhaustion_threads_events)
451 tty->print_cr("can_generate_resource_exhaustion_threads_events");
452 }
453
454 #endif