1 /* 2 * Copyright (c) 2015, 2017, 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 "classfile/javaClasses.hpp" 27 #include "classfile/javaClasses.inline.hpp" 28 #include "classfile/vmSymbols.hpp" 29 #include "logging/log.hpp" 30 #include "logging/logStream.hpp" 31 #include "memory/oopFactory.hpp" 32 #include "oops/oop.inline.hpp" 33 #include "oops/objArrayOop.inline.hpp" 34 #include "prims/stackwalk.hpp" 35 #include "runtime/globals.hpp" 36 #include "runtime/handles.inline.hpp" 37 #include "runtime/javaCalls.hpp" 38 #include "runtime/vframe.hpp" 39 #include "utilities/globalDefinitions.hpp" 40 41 // setup and cleanup actions 42 void BaseFrameStream::setup_magic_on_entry(objArrayHandle frames_array) { 43 frames_array->obj_at_put(magic_pos, _thread->threadObj()); 44 _anchor = address_value(); 45 assert(check_magic(frames_array), "invalid magic"); 46 } 47 48 bool BaseFrameStream::check_magic(objArrayHandle frames_array) { 49 oop m1 = frames_array->obj_at(magic_pos); 50 jlong m2 = _anchor; 51 if (m1 == _thread->threadObj() && m2 == address_value()) return true; 52 return false; 53 } 54 55 bool BaseFrameStream::cleanup_magic_on_exit(objArrayHandle frames_array) { 56 bool ok = check_magic(frames_array); 57 frames_array->obj_at_put(magic_pos, NULL); 58 _anchor = 0L; 59 return ok; 60 } 61 62 JavaFrameStream::JavaFrameStream(JavaThread* thread, int mode) 63 : BaseFrameStream(thread), _vfst(thread) { 64 _need_method_info = StackWalk::need_method_info(mode); 65 } 66 67 // Returns the BaseFrameStream for the current stack being traversed. 68 // 69 // Parameters: 70 // thread Current Java thread. 71 // magic Magic value used for each stack walking 72 // frames_array User-supplied buffers. The 0th element is reserved 73 // for this BaseFrameStream to use 74 // 75 BaseFrameStream* BaseFrameStream::from_current(JavaThread* thread, jlong magic, 76 objArrayHandle frames_array) 77 { 78 assert(thread != NULL && thread->is_Java_thread(), ""); 79 oop m1 = frames_array->obj_at(magic_pos); 80 if (m1 != thread->threadObj()) return NULL; 81 if (magic == 0L) return NULL; 82 BaseFrameStream* stream = (BaseFrameStream*) (intptr_t) magic; 83 if (!stream->is_valid_in(thread, frames_array)) return NULL; 84 return stream; 85 } 86 87 // Unpacks one or more frames into user-supplied buffers. 88 // Updates the end index, and returns the number of unpacked frames. 89 // Always start with the existing vfst.method and bci. 90 // Do not call vfst.next to advance over the last returned value. 91 // In other words, do not leave any stale data in the vfst. 92 // 93 // Parameters: 94 // mode Restrict which frames to be decoded. 95 // BaseFrameStream stream of frames 96 // max_nframes Maximum number of frames to be filled. 97 // start_index Start index to the user-supplied buffers. 98 // frames_array Buffer to store Class or StackFrame in, starting at start_index. 99 // frames array is a Class<?>[] array when only getting caller 100 // reference, and a StackFrameInfo[] array (or derivative) 101 // otherwise. It should never be null. 102 // end_index End index to the user-supplied buffers with unpacked frames. 103 // 104 // Returns the number of frames whose information was transferred into the buffers. 105 // 106 int StackWalk::fill_in_frames(jlong mode, BaseFrameStream& stream, 107 int max_nframes, int start_index, 108 objArrayHandle frames_array, 109 int& end_index, TRAPS) { 110 log_debug(stackwalk)("fill_in_frames limit=%d start=%d frames length=%d", 111 max_nframes, start_index, frames_array->length()); 112 assert(max_nframes > 0, "invalid max_nframes"); 113 assert(start_index + max_nframes <= frames_array->length(), "oob"); 114 115 int frames_decoded = 0; 116 for (; !stream.at_end(); stream.next()) { 117 Method* method = stream.method(); 118 119 if (method == NULL) continue; 120 121 // skip hidden frames for default StackWalker option (i.e. SHOW_HIDDEN_FRAMES 122 // not set) and when StackWalker::getCallerClass is called 123 if (!ShowHiddenFrames && (skip_hidden_frames(mode) || get_caller_class(mode))) { 124 if (method->is_hidden()) { 125 LogTarget(Debug, stackwalk) lt; 126 if (lt.is_enabled()) { 127 ResourceMark rm(THREAD); 128 LogStream ls(lt); 129 ls.print(" hidden method: "); 130 method->print_short_name(&ls); 131 ls.cr(); 132 } 133 continue; 134 } 135 } 136 137 int index = end_index++; 138 LogTarget(Debug, stackwalk) lt; 139 if (lt.is_enabled()) { 140 ResourceMark rm(THREAD); 141 LogStream ls(lt); 142 ls.print(" %d: frame method: ", index); 143 method->print_short_name(&ls); 144 ls.print_cr(" bci=%d", stream.bci()); 145 } 146 147 if (!need_method_info(mode) && get_caller_class(mode) && 148 index == start_index && method->caller_sensitive()) { 149 ResourceMark rm(THREAD); 150 THROW_MSG_0(vmSymbols::java_lang_UnsupportedOperationException(), 151 err_msg("StackWalker::getCallerClass called from @CallerSensitive %s method", 152 method->name_and_sig_as_C_string())); 153 } 154 // fill in StackFrameInfo and initialize MemberName 155 stream.fill_frame(index, frames_array, method, CHECK_0); 156 if (++frames_decoded >= max_nframes) break; 157 } 158 return frames_decoded; 159 } 160 161 // Fill in the LiveStackFrameInfo at the given index in frames_array 162 void LiveFrameStream::fill_frame(int index, objArrayHandle frames_array, 163 const methodHandle& method, TRAPS) { 164 Handle stackFrame(THREAD, frames_array->obj_at(index)); 165 fill_live_stackframe(stackFrame, method, CHECK); 166 } 167 168 // Fill in the StackFrameInfo at the given index in frames_array 169 void JavaFrameStream::fill_frame(int index, objArrayHandle frames_array, 170 const methodHandle& method, TRAPS) { 171 if (_need_method_info) { 172 Handle stackFrame(THREAD, frames_array->obj_at(index)); 173 fill_stackframe(stackFrame, method, CHECK); 174 } else { 175 frames_array->obj_at_put(index, method->method_holder()->java_mirror()); 176 } 177 } 178 179 // Create and return a LiveStackFrame.PrimitiveSlot (if needed) for the 180 // StackValue at the given index. 'type' is expected to be T_INT, T_LONG, 181 // T_OBJECT, or T_CONFLICT. 182 oop LiveFrameStream::create_primitive_slot_instance(StackValueCollection* values, 183 int i, BasicType type, TRAPS) { 184 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::java_lang_LiveStackFrameInfo(), CHECK_NULL); 185 InstanceKlass* ik = InstanceKlass::cast(k); 186 187 JavaValue result(T_OBJECT); 188 JavaCallArguments args; 189 Symbol* signature = NULL; 190 191 // ## TODO: type is only available in LocalVariable table, if present. 192 // ## StackValue type is T_INT or T_OBJECT (or converted to T_LONG on 64-bit) 193 switch (type) { 194 case T_INT: 195 args.push_int(values->int_at(i)); 196 signature = vmSymbols::asPrimitive_int_signature(); 197 break; 198 199 case T_LONG: 200 args.push_long(values->long_at(i)); 201 signature = vmSymbols::asPrimitive_long_signature(); 202 break; 203 204 case T_FLOAT: 205 case T_DOUBLE: 206 case T_BYTE: 207 case T_SHORT: 208 case T_CHAR: 209 case T_BOOLEAN: 210 THROW_MSG_(vmSymbols::java_lang_InternalError(), "Unexpected StackValue type", NULL); 211 212 case T_OBJECT: 213 return values->obj_at(i)(); 214 215 case T_CONFLICT: 216 // put a non-null slot 217 #ifdef _LP64 218 args.push_long(0); 219 signature = vmSymbols::asPrimitive_long_signature(); 220 #else 221 args.push_int(0); 222 signature = vmSymbols::asPrimitive_int_signature(); 223 #endif 224 225 break; 226 227 default: ShouldNotReachHere(); 228 } 229 JavaCalls::call_static(&result, 230 ik, 231 vmSymbols::asPrimitive_name(), 232 signature, 233 &args, 234 CHECK_NULL); 235 return (instanceOop) result.get_jobject(); 236 } 237 238 objArrayHandle LiveFrameStream::values_to_object_array(StackValueCollection* values, TRAPS) { 239 objArrayHandle empty; 240 int length = values->size(); 241 objArrayOop array_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 242 length, CHECK_(empty)); 243 objArrayHandle array_h(THREAD, array_oop); 244 for (int i = 0; i < values->size(); i++) { 245 StackValue* st = values->at(i); 246 BasicType type = st->type(); 247 int index = i; 248 #ifdef _LP64 249 if (type != T_OBJECT && type != T_CONFLICT) { 250 intptr_t ret = st->get_int(); // read full 64-bit slot 251 type = T_LONG; // treat as long 252 index--; // undo +1 in StackValueCollection::long_at 253 } 254 #endif 255 oop obj = create_primitive_slot_instance(values, index, type, CHECK_(empty)); 256 if (obj != NULL) { 257 array_h->obj_at_put(i, obj); 258 } 259 } 260 return array_h; 261 } 262 263 objArrayHandle LiveFrameStream::monitors_to_object_array(GrowableArray<MonitorInfo*>* monitors, TRAPS) { 264 int length = monitors->length(); 265 objArrayOop array_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 266 length, CHECK_(objArrayHandle())); 267 objArrayHandle array_h(THREAD, array_oop); 268 for (int i = 0; i < length; i++) { 269 MonitorInfo* monitor = monitors->at(i); 270 array_h->obj_at_put(i, monitor->owner()); 271 } 272 return array_h; 273 } 274 275 // Fill StackFrameInfo with declaringClass and bci and initialize memberName 276 void BaseFrameStream::fill_stackframe(Handle stackFrame, const methodHandle& method, TRAPS) { 277 java_lang_StackFrameInfo::set_declaringClass(stackFrame(), method->method_holder()->java_mirror()); 278 java_lang_StackFrameInfo::set_method_and_bci(stackFrame, method, bci(), THREAD); 279 } 280 281 // Fill LiveStackFrameInfo with locals, monitors, and expressions 282 void LiveFrameStream::fill_live_stackframe(Handle stackFrame, 283 const methodHandle& method, TRAPS) { 284 fill_stackframe(stackFrame, method, CHECK); 285 if (_jvf != NULL) { 286 StackValueCollection* locals = _jvf->locals(); 287 StackValueCollection* expressions = _jvf->expressions(); 288 GrowableArray<MonitorInfo*>* monitors = _jvf->monitors(); 289 290 int mode = 0; 291 if (_jvf->is_interpreted_frame()) { 292 mode = MODE_INTERPRETED; 293 } else if (_jvf->is_compiled_frame()) { 294 mode = MODE_COMPILED; 295 } 296 297 if (!locals->is_empty()) { 298 objArrayHandle locals_h = values_to_object_array(locals, CHECK); 299 java_lang_LiveStackFrameInfo::set_locals(stackFrame(), locals_h()); 300 } 301 if (!expressions->is_empty()) { 302 objArrayHandle expressions_h = values_to_object_array(expressions, CHECK); 303 java_lang_LiveStackFrameInfo::set_operands(stackFrame(), expressions_h()); 304 } 305 if (monitors->length() > 0) { 306 objArrayHandle monitors_h = monitors_to_object_array(monitors, CHECK); 307 java_lang_LiveStackFrameInfo::set_monitors(stackFrame(), monitors_h()); 308 } 309 java_lang_LiveStackFrameInfo::set_mode(stackFrame(), mode); 310 } 311 } 312 313 // Begins stack walking. 314 // 315 // Parameters: 316 // stackStream StackStream object 317 // mode Stack walking mode. 318 // skip_frames Number of frames to be skipped. 319 // frame_count Number of frames to be traversed. 320 // start_index Start index to the user-supplied buffers. 321 // frames_array Buffer to store StackFrame in, starting at start_index. 322 // frames array is a Class<?>[] array when only getting caller 323 // reference, and a StackFrameInfo[] array (or derivative) 324 // otherwise. It should never be null. 325 // 326 // Returns Object returned from AbstractStackWalker::doStackWalk call. 327 // 328 oop StackWalk::walk(Handle stackStream, jlong mode, 329 int skip_frames, int frame_count, int start_index, 330 objArrayHandle frames_array, 331 TRAPS) { 332 ResourceMark rm(THREAD); 333 JavaThread* jt = (JavaThread*)THREAD; 334 log_debug(stackwalk)("Start walking: mode " JLONG_FORMAT " skip %d frames batch size %d", 335 mode, skip_frames, frame_count); 336 337 if (frames_array.is_null()) { 338 THROW_MSG_(vmSymbols::java_lang_NullPointerException(), "frames_array is NULL", NULL); 339 } 340 341 // Setup traversal onto my stack. 342 if (live_frame_info(mode)) { 343 assert (use_frames_array(mode), "Bad mode for get live frame"); 344 RegisterMap regMap(jt, true); 345 LiveFrameStream stream(jt, ®Map); 346 return fetchFirstBatch(stream, stackStream, mode, skip_frames, frame_count, 347 start_index, frames_array, THREAD); 348 } else { 349 JavaFrameStream stream(jt, mode); 350 return fetchFirstBatch(stream, stackStream, mode, skip_frames, frame_count, 351 start_index, frames_array, THREAD); 352 } 353 } 354 355 oop StackWalk::fetchFirstBatch(BaseFrameStream& stream, Handle stackStream, 356 jlong mode, int skip_frames, int frame_count, 357 int start_index, objArrayHandle frames_array, TRAPS) { 358 methodHandle m_doStackWalk(THREAD, Universe::do_stack_walk_method()); 359 360 { 361 Klass* stackWalker_klass = SystemDictionary::StackWalker_klass(); 362 Klass* abstractStackWalker_klass = SystemDictionary::AbstractStackWalker_klass(); 363 while (!stream.at_end()) { 364 InstanceKlass* ik = stream.method()->method_holder(); 365 if (ik != stackWalker_klass && 366 ik != abstractStackWalker_klass && ik->super() != abstractStackWalker_klass) { 367 break; 368 } 369 370 LogTarget(Debug, stackwalk) lt; 371 if (lt.is_enabled()) { 372 ResourceMark rm(THREAD); 373 LogStream ls(lt); 374 ls.print(" skip "); 375 stream.method()->print_short_name(&ls); 376 ls.cr(); 377 } 378 stream.next(); 379 } 380 381 // stack frame has been traversed individually and resume stack walk 382 // from the stack frame at depth == skip_frames. 383 for (int n=0; n < skip_frames && !stream.at_end(); stream.next(), n++) { 384 LogTarget(Debug, stackwalk) lt; 385 if (lt.is_enabled()) { 386 ResourceMark rm(THREAD); 387 LogStream ls(lt); 388 ls.print(" skip "); 389 stream.method()->print_short_name(&ls); 390 ls.cr(); 391 } 392 } 393 } 394 395 int end_index = start_index; 396 int numFrames = 0; 397 if (!stream.at_end()) { 398 numFrames = fill_in_frames(mode, stream, frame_count, start_index, 399 frames_array, end_index, CHECK_NULL); 400 if (numFrames < 1) { 401 THROW_MSG_(vmSymbols::java_lang_InternalError(), "stack walk: decode failed", NULL); 402 } 403 } 404 405 // JVM_CallStackWalk walks the stack and fills in stack frames, then calls to 406 // Java method java.lang.StackStreamFactory.AbstractStackWalker::doStackWalk 407 // which calls the implementation to consume the stack frames. 408 // When JVM_CallStackWalk returns, it invalidates the stack stream. 409 JavaValue result(T_OBJECT); 410 JavaCallArguments args(stackStream); 411 args.push_long(stream.address_value()); 412 args.push_int(skip_frames); 413 args.push_int(frame_count); 414 args.push_int(start_index); 415 args.push_int(end_index); 416 417 // Link the thread and vframe stream into the callee-visible object 418 stream.setup_magic_on_entry(frames_array); 419 420 JavaCalls::call(&result, m_doStackWalk, &args, THREAD); 421 422 // Do this before anything else happens, to disable any lingering stream objects 423 bool ok = stream.cleanup_magic_on_exit(frames_array); 424 425 // Throw pending exception if we must 426 (void) (CHECK_NULL); 427 428 if (!ok) { 429 THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: corrupted buffers on exit", NULL); 430 } 431 432 // Return normally 433 return (oop)result.get_jobject(); 434 } 435 436 // Walk the next batch of stack frames 437 // 438 // Parameters: 439 // stackStream StackStream object 440 // mode Stack walking mode. 441 // magic Must be valid value to continue the stack walk 442 // frame_count Number of frames to be decoded. 443 // start_index Start index to the user-supplied buffers. 444 // frames_array Buffer to store StackFrame in, starting at start_index. 445 // 446 // Returns the end index of frame filled in the buffer. 447 // 448 jint StackWalk::fetchNextBatch(Handle stackStream, jlong mode, jlong magic, 449 int frame_count, int start_index, 450 objArrayHandle frames_array, 451 TRAPS) 452 { 453 JavaThread* jt = (JavaThread*)THREAD; 454 BaseFrameStream* existing_stream = BaseFrameStream::from_current(jt, magic, frames_array); 455 if (existing_stream == NULL) { 456 THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: corrupted buffers", 0L); 457 } 458 459 if (frames_array.is_null()) { 460 THROW_MSG_(vmSymbols::java_lang_NullPointerException(), "frames_array is NULL", 0L); 461 } 462 463 log_debug(stackwalk)("StackWalk::fetchNextBatch frame_count %d existing_stream " 464 PTR_FORMAT " start %d frames %d", 465 frame_count, p2i(existing_stream), start_index, frames_array->length()); 466 int end_index = start_index; 467 if (frame_count <= 0) { 468 return end_index; // No operation. 469 } 470 471 int count = frame_count + start_index; 472 assert (frames_array->length() >= count, "not enough space in buffers"); 473 474 BaseFrameStream& stream = (*existing_stream); 475 if (!stream.at_end()) { 476 stream.next(); // advance past the last frame decoded in previous batch 477 if (!stream.at_end()) { 478 int n = fill_in_frames(mode, stream, frame_count, start_index, 479 frames_array, end_index, CHECK_0); 480 if (n < 1) { 481 THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: later decode failed", 0L); 482 } 483 return end_index; 484 } 485 } 486 return end_index; 487 }