backtrace_test.cpp revision 2c43cff01d1271be451671567955158629b23670
1/* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include <dirent.h> 18#include <errno.h> 19#include <inttypes.h> 20#include <pthread.h> 21#include <signal.h> 22#include <stdint.h> 23#include <stdio.h> 24#include <stdlib.h> 25#include <string.h> 26#include <sys/ptrace.h> 27#include <sys/types.h> 28#include <sys/wait.h> 29#include <time.h> 30#include <unistd.h> 31 32#include <backtrace/Backtrace.h> 33#include <backtrace/BacktraceMap.h> 34 35// For the THREAD_SIGNAL definition. 36#include "BacktraceCurrent.h" 37 38#include <cutils/atomic.h> 39#include <gtest/gtest.h> 40 41#include <algorithm> 42#include <memory> 43#include <string> 44#include <vector> 45 46#include "thread_utils.h" 47 48// Number of microseconds per milliseconds. 49#define US_PER_MSEC 1000 50 51// Number of nanoseconds in a second. 52#define NS_PER_SEC 1000000000ULL 53 54// Number of simultaneous dumping operations to perform. 55#define NUM_THREADS 40 56 57// Number of simultaneous threads running in our forked process. 58#define NUM_PTRACE_THREADS 5 59 60struct thread_t { 61 pid_t tid; 62 int32_t state; 63 pthread_t threadId; 64 void* data; 65}; 66 67struct dump_thread_t { 68 thread_t thread; 69 Backtrace* backtrace; 70 int32_t* now; 71 int32_t done; 72}; 73 74extern "C" { 75// Prototypes for functions in the test library. 76int test_level_one(int, int, int, int, void (*)(void*), void*); 77 78int test_recursive_call(int, void (*)(void*), void*); 79} 80 81uint64_t NanoTime() { 82 struct timespec t = { 0, 0 }; 83 clock_gettime(CLOCK_MONOTONIC, &t); 84 return static_cast<uint64_t>(t.tv_sec * NS_PER_SEC + t.tv_nsec); 85} 86 87std::string DumpFrames(Backtrace* backtrace) { 88 if (backtrace->NumFrames() == 0) { 89 return " No frames to dump\n"; 90 } 91 92 std::string frame; 93 for (size_t i = 0; i < backtrace->NumFrames(); i++) { 94 frame += " " + backtrace->FormatFrameData(i) + '\n'; 95 } 96 return frame; 97} 98 99void WaitForStop(pid_t pid) { 100 uint64_t start = NanoTime(); 101 102 siginfo_t si; 103 while (ptrace(PTRACE_GETSIGINFO, pid, 0, &si) < 0 && (errno == EINTR || errno == ESRCH)) { 104 if ((NanoTime() - start) > NS_PER_SEC) { 105 printf("The process did not get to a stopping point in 1 second.\n"); 106 break; 107 } 108 usleep(US_PER_MSEC); 109 } 110} 111 112bool ReadyLevelBacktrace(Backtrace* backtrace) { 113 // See if test_level_four is in the backtrace. 114 bool found = false; 115 for (Backtrace::const_iterator it = backtrace->begin(); it != backtrace->end(); ++it) { 116 if (it->func_name == "test_level_four") { 117 found = true; 118 break; 119 } 120 } 121 122 return found; 123} 124 125void VerifyLevelDump(Backtrace* backtrace) { 126 ASSERT_GT(backtrace->NumFrames(), static_cast<size_t>(0)); 127 ASSERT_LT(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES)); 128 129 // Look through the frames starting at the highest to find the 130 // frame we want. 131 size_t frame_num = 0; 132 for (size_t i = backtrace->NumFrames()-1; i > 2; i--) { 133 if (backtrace->GetFrame(i)->func_name == "test_level_one") { 134 frame_num = i; 135 break; 136 } 137 } 138 ASSERT_LT(static_cast<size_t>(0), frame_num) << DumpFrames(backtrace); 139 ASSERT_LE(static_cast<size_t>(3), frame_num) << DumpFrames(backtrace); 140 141 ASSERT_EQ(backtrace->GetFrame(frame_num)->func_name, "test_level_one"); 142 ASSERT_EQ(backtrace->GetFrame(frame_num-1)->func_name, "test_level_two"); 143 ASSERT_EQ(backtrace->GetFrame(frame_num-2)->func_name, "test_level_three"); 144 ASSERT_EQ(backtrace->GetFrame(frame_num-3)->func_name, "test_level_four"); 145} 146 147void VerifyLevelBacktrace(void*) { 148 std::unique_ptr<Backtrace> backtrace( 149 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 150 ASSERT_TRUE(backtrace.get() != nullptr); 151 ASSERT_TRUE(backtrace->Unwind(0)); 152 153 VerifyLevelDump(backtrace.get()); 154} 155 156bool ReadyMaxBacktrace(Backtrace* backtrace) { 157 return (backtrace->NumFrames() == MAX_BACKTRACE_FRAMES); 158} 159 160void VerifyMaxDump(Backtrace* backtrace) { 161 ASSERT_EQ(backtrace->NumFrames(), static_cast<size_t>(MAX_BACKTRACE_FRAMES)); 162 // Verify that the last frame is our recursive call. 163 ASSERT_EQ(backtrace->GetFrame(MAX_BACKTRACE_FRAMES-1)->func_name, 164 "test_recursive_call"); 165} 166 167void VerifyMaxBacktrace(void*) { 168 std::unique_ptr<Backtrace> backtrace( 169 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 170 ASSERT_TRUE(backtrace.get() != nullptr); 171 ASSERT_TRUE(backtrace->Unwind(0)); 172 173 VerifyMaxDump(backtrace.get()); 174} 175 176void ThreadSetState(void* data) { 177 thread_t* thread = reinterpret_cast<thread_t*>(data); 178 android_atomic_acquire_store(1, &thread->state); 179 volatile int i = 0; 180 while (thread->state) { 181 i++; 182 } 183} 184 185void VerifyThreadTest(pid_t tid, void (*VerifyFunc)(Backtrace*)) { 186 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), tid)); 187 ASSERT_TRUE(backtrace.get() != nullptr); 188 ASSERT_TRUE(backtrace->Unwind(0)); 189 190 VerifyFunc(backtrace.get()); 191} 192 193bool WaitForNonZero(int32_t* value, uint64_t seconds) { 194 uint64_t start = NanoTime(); 195 do { 196 if (android_atomic_acquire_load(value)) { 197 return true; 198 } 199 } while ((NanoTime() - start) < seconds * NS_PER_SEC); 200 return false; 201} 202 203TEST(libbacktrace, local_trace) { 204 ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelBacktrace, nullptr), 0); 205} 206 207void VerifyIgnoreFrames( 208 Backtrace* bt_all, Backtrace* bt_ign1, 209 Backtrace* bt_ign2, const char* cur_proc) { 210 EXPECT_EQ(bt_all->NumFrames(), bt_ign1->NumFrames() + 1); 211 EXPECT_EQ(bt_all->NumFrames(), bt_ign2->NumFrames() + 2); 212 213 // Check all of the frames are the same > the current frame. 214 bool check = (cur_proc == nullptr); 215 for (size_t i = 0; i < bt_ign2->NumFrames(); i++) { 216 if (check) { 217 EXPECT_EQ(bt_ign2->GetFrame(i)->pc, bt_ign1->GetFrame(i+1)->pc); 218 EXPECT_EQ(bt_ign2->GetFrame(i)->sp, bt_ign1->GetFrame(i+1)->sp); 219 EXPECT_EQ(bt_ign2->GetFrame(i)->stack_size, bt_ign1->GetFrame(i+1)->stack_size); 220 221 EXPECT_EQ(bt_ign2->GetFrame(i)->pc, bt_all->GetFrame(i+2)->pc); 222 EXPECT_EQ(bt_ign2->GetFrame(i)->sp, bt_all->GetFrame(i+2)->sp); 223 EXPECT_EQ(bt_ign2->GetFrame(i)->stack_size, bt_all->GetFrame(i+2)->stack_size); 224 } 225 if (!check && bt_ign2->GetFrame(i)->func_name == cur_proc) { 226 check = true; 227 } 228 } 229} 230 231void VerifyLevelIgnoreFrames(void*) { 232 std::unique_ptr<Backtrace> all( 233 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 234 ASSERT_TRUE(all.get() != nullptr); 235 ASSERT_TRUE(all->Unwind(0)); 236 237 std::unique_ptr<Backtrace> ign1( 238 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 239 ASSERT_TRUE(ign1.get() != nullptr); 240 ASSERT_TRUE(ign1->Unwind(1)); 241 242 std::unique_ptr<Backtrace> ign2( 243 Backtrace::Create(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD)); 244 ASSERT_TRUE(ign2.get() != nullptr); 245 ASSERT_TRUE(ign2->Unwind(2)); 246 247 VerifyIgnoreFrames(all.get(), ign1.get(), ign2.get(), "VerifyLevelIgnoreFrames"); 248} 249 250TEST(libbacktrace, local_trace_ignore_frames) { 251 ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelIgnoreFrames, nullptr), 0); 252} 253 254TEST(libbacktrace, local_max_trace) { 255 ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, VerifyMaxBacktrace, nullptr), 0); 256} 257 258void VerifyProcTest(pid_t pid, pid_t tid, bool share_map, 259 bool (*ReadyFunc)(Backtrace*), 260 void (*VerifyFunc)(Backtrace*)) { 261 pid_t ptrace_tid; 262 if (tid < 0) { 263 ptrace_tid = pid; 264 } else { 265 ptrace_tid = tid; 266 } 267 uint64_t start = NanoTime(); 268 bool verified = false; 269 do { 270 usleep(US_PER_MSEC); 271 if (ptrace(PTRACE_ATTACH, ptrace_tid, 0, 0) == 0) { 272 // Wait for the process to get to a stopping point. 273 WaitForStop(ptrace_tid); 274 275 std::unique_ptr<BacktraceMap> map; 276 if (share_map) { 277 map.reset(BacktraceMap::Create(pid)); 278 } 279 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map.get())); 280 ASSERT_TRUE(backtrace->Unwind(0)); 281 ASSERT_TRUE(backtrace.get() != nullptr); 282 if (ReadyFunc(backtrace.get())) { 283 VerifyFunc(backtrace.get()); 284 verified = true; 285 } 286 287 ASSERT_TRUE(ptrace(PTRACE_DETACH, ptrace_tid, 0, 0) == 0); 288 } 289 // If 5 seconds have passed, then we are done. 290 } while (!verified && (NanoTime() - start) <= 5 * NS_PER_SEC); 291 ASSERT_TRUE(verified); 292} 293 294TEST(libbacktrace, ptrace_trace) { 295 pid_t pid; 296 if ((pid = fork()) == 0) { 297 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 298 _exit(1); 299 } 300 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyLevelBacktrace, VerifyLevelDump); 301 302 kill(pid, SIGKILL); 303 int status; 304 ASSERT_EQ(waitpid(pid, &status, 0), pid); 305} 306 307TEST(libbacktrace, ptrace_trace_shared_map) { 308 pid_t pid; 309 if ((pid = fork()) == 0) { 310 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 311 _exit(1); 312 } 313 314 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, true, ReadyLevelBacktrace, VerifyLevelDump); 315 316 kill(pid, SIGKILL); 317 int status; 318 ASSERT_EQ(waitpid(pid, &status, 0), pid); 319} 320 321TEST(libbacktrace, ptrace_max_trace) { 322 pid_t pid; 323 if ((pid = fork()) == 0) { 324 ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, nullptr, nullptr), 0); 325 _exit(1); 326 } 327 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyMaxBacktrace, VerifyMaxDump); 328 329 kill(pid, SIGKILL); 330 int status; 331 ASSERT_EQ(waitpid(pid, &status, 0), pid); 332} 333 334void VerifyProcessIgnoreFrames(Backtrace* bt_all) { 335 std::unique_ptr<Backtrace> ign1(Backtrace::Create(bt_all->Pid(), BACKTRACE_CURRENT_THREAD)); 336 ASSERT_TRUE(ign1.get() != nullptr); 337 ASSERT_TRUE(ign1->Unwind(1)); 338 339 std::unique_ptr<Backtrace> ign2(Backtrace::Create(bt_all->Pid(), BACKTRACE_CURRENT_THREAD)); 340 ASSERT_TRUE(ign2.get() != nullptr); 341 ASSERT_TRUE(ign2->Unwind(2)); 342 343 VerifyIgnoreFrames(bt_all, ign1.get(), ign2.get(), nullptr); 344} 345 346TEST(libbacktrace, ptrace_ignore_frames) { 347 pid_t pid; 348 if ((pid = fork()) == 0) { 349 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 350 _exit(1); 351 } 352 VerifyProcTest(pid, BACKTRACE_CURRENT_THREAD, false, ReadyLevelBacktrace, VerifyProcessIgnoreFrames); 353 354 kill(pid, SIGKILL); 355 int status; 356 ASSERT_EQ(waitpid(pid, &status, 0), pid); 357} 358 359// Create a process with multiple threads and dump all of the threads. 360void* PtraceThreadLevelRun(void*) { 361 EXPECT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 362 return nullptr; 363} 364 365void GetThreads(pid_t pid, std::vector<pid_t>* threads) { 366 // Get the list of tasks. 367 char task_path[128]; 368 snprintf(task_path, sizeof(task_path), "/proc/%d/task", pid); 369 370 DIR* tasks_dir = opendir(task_path); 371 ASSERT_TRUE(tasks_dir != nullptr); 372 struct dirent* entry; 373 while ((entry = readdir(tasks_dir)) != nullptr) { 374 char* end; 375 pid_t tid = strtoul(entry->d_name, &end, 10); 376 if (*end == '\0') { 377 threads->push_back(tid); 378 } 379 } 380 closedir(tasks_dir); 381} 382 383TEST(libbacktrace, ptrace_threads) { 384 pid_t pid; 385 if ((pid = fork()) == 0) { 386 for (size_t i = 0; i < NUM_PTRACE_THREADS; i++) { 387 pthread_attr_t attr; 388 pthread_attr_init(&attr); 389 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 390 391 pthread_t thread; 392 ASSERT_TRUE(pthread_create(&thread, &attr, PtraceThreadLevelRun, nullptr) == 0); 393 } 394 ASSERT_NE(test_level_one(1, 2, 3, 4, nullptr, nullptr), 0); 395 _exit(1); 396 } 397 398 // Check to see that all of the threads are running before unwinding. 399 std::vector<pid_t> threads; 400 uint64_t start = NanoTime(); 401 do { 402 usleep(US_PER_MSEC); 403 threads.clear(); 404 GetThreads(pid, &threads); 405 } while ((threads.size() != NUM_PTRACE_THREADS + 1) && 406 ((NanoTime() - start) <= 5 * NS_PER_SEC)); 407 ASSERT_EQ(threads.size(), static_cast<size_t>(NUM_PTRACE_THREADS + 1)); 408 409 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 410 WaitForStop(pid); 411 for (std::vector<int>::const_iterator it = threads.begin(); it != threads.end(); ++it) { 412 // Skip the current forked process, we only care about the threads. 413 if (pid == *it) { 414 continue; 415 } 416 VerifyProcTest(pid, *it, false, ReadyLevelBacktrace, VerifyLevelDump); 417 } 418 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 419 420 kill(pid, SIGKILL); 421 int status; 422 ASSERT_EQ(waitpid(pid, &status, 0), pid); 423} 424 425void VerifyLevelThread(void*) { 426 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), gettid())); 427 ASSERT_TRUE(backtrace.get() != nullptr); 428 ASSERT_TRUE(backtrace->Unwind(0)); 429 430 VerifyLevelDump(backtrace.get()); 431} 432 433TEST(libbacktrace, thread_current_level) { 434 ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelThread, nullptr), 0); 435} 436 437void VerifyMaxThread(void*) { 438 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), gettid())); 439 ASSERT_TRUE(backtrace.get() != nullptr); 440 ASSERT_TRUE(backtrace->Unwind(0)); 441 442 VerifyMaxDump(backtrace.get()); 443} 444 445TEST(libbacktrace, thread_current_max) { 446 ASSERT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, VerifyMaxThread, nullptr), 0); 447} 448 449void* ThreadLevelRun(void* data) { 450 thread_t* thread = reinterpret_cast<thread_t*>(data); 451 452 thread->tid = gettid(); 453 EXPECT_NE(test_level_one(1, 2, 3, 4, ThreadSetState, data), 0); 454 return nullptr; 455} 456 457TEST(libbacktrace, thread_level_trace) { 458 pthread_attr_t attr; 459 pthread_attr_init(&attr); 460 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 461 462 thread_t thread_data = { 0, 0, 0, nullptr }; 463 pthread_t thread; 464 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadLevelRun, &thread_data) == 0); 465 466 // Wait up to 2 seconds for the tid to be set. 467 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 468 469 // Make sure that the thread signal used is not visible when compiled for 470 // the target. 471#if !defined(__GLIBC__) 472 ASSERT_LT(THREAD_SIGNAL, SIGRTMIN); 473#endif 474 475 // Save the current signal action and make sure it is restored afterwards. 476 struct sigaction cur_action; 477 ASSERT_TRUE(sigaction(THREAD_SIGNAL, nullptr, &cur_action) == 0); 478 479 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid)); 480 ASSERT_TRUE(backtrace.get() != nullptr); 481 ASSERT_TRUE(backtrace->Unwind(0)); 482 483 VerifyLevelDump(backtrace.get()); 484 485 // Tell the thread to exit its infinite loop. 486 android_atomic_acquire_store(0, &thread_data.state); 487 488 // Verify that the old action was restored. 489 struct sigaction new_action; 490 ASSERT_TRUE(sigaction(THREAD_SIGNAL, nullptr, &new_action) == 0); 491 EXPECT_EQ(cur_action.sa_sigaction, new_action.sa_sigaction); 492 // The SA_RESTORER flag gets set behind our back, so a direct comparison 493 // doesn't work unless we mask the value off. Mips doesn't have this 494 // flag, so skip this on that platform. 495#if defined(SA_RESTORER) 496 cur_action.sa_flags &= ~SA_RESTORER; 497 new_action.sa_flags &= ~SA_RESTORER; 498#elif defined(__GLIBC__) 499 // Our host compiler doesn't appear to define this flag for some reason. 500 cur_action.sa_flags &= ~0x04000000; 501 new_action.sa_flags &= ~0x04000000; 502#endif 503 EXPECT_EQ(cur_action.sa_flags, new_action.sa_flags); 504} 505 506TEST(libbacktrace, thread_ignore_frames) { 507 pthread_attr_t attr; 508 pthread_attr_init(&attr); 509 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 510 511 thread_t thread_data = { 0, 0, 0, nullptr }; 512 pthread_t thread; 513 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadLevelRun, &thread_data) == 0); 514 515 // Wait up to 2 seconds for the tid to be set. 516 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 517 518 std::unique_ptr<Backtrace> all(Backtrace::Create(getpid(), thread_data.tid)); 519 ASSERT_TRUE(all.get() != nullptr); 520 ASSERT_TRUE(all->Unwind(0)); 521 522 std::unique_ptr<Backtrace> ign1(Backtrace::Create(getpid(), thread_data.tid)); 523 ASSERT_TRUE(ign1.get() != nullptr); 524 ASSERT_TRUE(ign1->Unwind(1)); 525 526 std::unique_ptr<Backtrace> ign2(Backtrace::Create(getpid(), thread_data.tid)); 527 ASSERT_TRUE(ign2.get() != nullptr); 528 ASSERT_TRUE(ign2->Unwind(2)); 529 530 VerifyIgnoreFrames(all.get(), ign1.get(), ign2.get(), nullptr); 531 532 // Tell the thread to exit its infinite loop. 533 android_atomic_acquire_store(0, &thread_data.state); 534} 535 536void* ThreadMaxRun(void* data) { 537 thread_t* thread = reinterpret_cast<thread_t*>(data); 538 539 thread->tid = gettid(); 540 EXPECT_NE(test_recursive_call(MAX_BACKTRACE_FRAMES+10, ThreadSetState, data), 0); 541 return nullptr; 542} 543 544TEST(libbacktrace, thread_max_trace) { 545 pthread_attr_t attr; 546 pthread_attr_init(&attr); 547 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 548 549 thread_t thread_data = { 0, 0, 0, nullptr }; 550 pthread_t thread; 551 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadMaxRun, &thread_data) == 0); 552 553 // Wait for the tid to be set. 554 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 555 556 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid)); 557 ASSERT_TRUE(backtrace.get() != nullptr); 558 ASSERT_TRUE(backtrace->Unwind(0)); 559 560 VerifyMaxDump(backtrace.get()); 561 562 // Tell the thread to exit its infinite loop. 563 android_atomic_acquire_store(0, &thread_data.state); 564} 565 566void* ThreadDump(void* data) { 567 dump_thread_t* dump = reinterpret_cast<dump_thread_t*>(data); 568 while (true) { 569 if (android_atomic_acquire_load(dump->now)) { 570 break; 571 } 572 } 573 574 // The status of the actual unwind will be checked elsewhere. 575 dump->backtrace = Backtrace::Create(getpid(), dump->thread.tid); 576 dump->backtrace->Unwind(0); 577 578 android_atomic_acquire_store(1, &dump->done); 579 580 return nullptr; 581} 582 583TEST(libbacktrace, thread_multiple_dump) { 584 // Dump NUM_THREADS simultaneously. 585 std::vector<thread_t> runners(NUM_THREADS); 586 std::vector<dump_thread_t> dumpers(NUM_THREADS); 587 588 pthread_attr_t attr; 589 pthread_attr_init(&attr); 590 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 591 for (size_t i = 0; i < NUM_THREADS; i++) { 592 // Launch the runners, they will spin in hard loops doing nothing. 593 runners[i].tid = 0; 594 runners[i].state = 0; 595 ASSERT_TRUE(pthread_create(&runners[i].threadId, &attr, ThreadMaxRun, &runners[i]) == 0); 596 } 597 598 // Wait for tids to be set. 599 for (std::vector<thread_t>::iterator it = runners.begin(); it != runners.end(); ++it) { 600 ASSERT_TRUE(WaitForNonZero(&it->state, 30)); 601 } 602 603 // Start all of the dumpers at once, they will spin until they are signalled 604 // to begin their dump run. 605 int32_t dump_now = 0; 606 for (size_t i = 0; i < NUM_THREADS; i++) { 607 dumpers[i].thread.tid = runners[i].tid; 608 dumpers[i].thread.state = 0; 609 dumpers[i].done = 0; 610 dumpers[i].now = &dump_now; 611 612 ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0); 613 } 614 615 // Start all of the dumpers going at once. 616 android_atomic_acquire_store(1, &dump_now); 617 618 for (size_t i = 0; i < NUM_THREADS; i++) { 619 ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 30)); 620 621 // Tell the runner thread to exit its infinite loop. 622 android_atomic_acquire_store(0, &runners[i].state); 623 624 ASSERT_TRUE(dumpers[i].backtrace != nullptr); 625 VerifyMaxDump(dumpers[i].backtrace); 626 627 delete dumpers[i].backtrace; 628 dumpers[i].backtrace = nullptr; 629 } 630} 631 632TEST(libbacktrace, thread_multiple_dump_same_thread) { 633 pthread_attr_t attr; 634 pthread_attr_init(&attr); 635 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 636 thread_t runner; 637 runner.tid = 0; 638 runner.state = 0; 639 ASSERT_TRUE(pthread_create(&runner.threadId, &attr, ThreadMaxRun, &runner) == 0); 640 641 // Wait for tids to be set. 642 ASSERT_TRUE(WaitForNonZero(&runner.state, 30)); 643 644 // Start all of the dumpers at once, they will spin until they are signalled 645 // to begin their dump run. 646 int32_t dump_now = 0; 647 // Dump the same thread NUM_THREADS simultaneously. 648 std::vector<dump_thread_t> dumpers(NUM_THREADS); 649 for (size_t i = 0; i < NUM_THREADS; i++) { 650 dumpers[i].thread.tid = runner.tid; 651 dumpers[i].thread.state = 0; 652 dumpers[i].done = 0; 653 dumpers[i].now = &dump_now; 654 655 ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0); 656 } 657 658 // Start all of the dumpers going at once. 659 android_atomic_acquire_store(1, &dump_now); 660 661 for (size_t i = 0; i < NUM_THREADS; i++) { 662 ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 30)); 663 664 ASSERT_TRUE(dumpers[i].backtrace != nullptr); 665 VerifyMaxDump(dumpers[i].backtrace); 666 667 delete dumpers[i].backtrace; 668 dumpers[i].backtrace = nullptr; 669 } 670 671 // Tell the runner thread to exit its infinite loop. 672 android_atomic_acquire_store(0, &runner.state); 673} 674 675// This test is for UnwindMaps that should share the same map cursor when 676// multiple maps are created for the current process at the same time. 677TEST(libbacktrace, simultaneous_maps) { 678 BacktraceMap* map1 = BacktraceMap::Create(getpid()); 679 BacktraceMap* map2 = BacktraceMap::Create(getpid()); 680 BacktraceMap* map3 = BacktraceMap::Create(getpid()); 681 682 Backtrace* back1 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map1); 683 EXPECT_TRUE(back1->Unwind(0)); 684 delete back1; 685 delete map1; 686 687 Backtrace* back2 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map2); 688 EXPECT_TRUE(back2->Unwind(0)); 689 delete back2; 690 delete map2; 691 692 Backtrace* back3 = Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD, map3); 693 EXPECT_TRUE(back3->Unwind(0)); 694 delete back3; 695 delete map3; 696} 697 698TEST(libbacktrace, fillin_erases) { 699 BacktraceMap* back_map = BacktraceMap::Create(getpid()); 700 701 backtrace_map_t map; 702 703 map.start = 1; 704 map.end = 3; 705 map.flags = 1; 706 map.name = "Initialized"; 707 back_map->FillIn(0, &map); 708 delete back_map; 709 710 ASSERT_FALSE(BacktraceMap::IsValid(map)); 711 ASSERT_EQ(static_cast<uintptr_t>(0), map.start); 712 ASSERT_EQ(static_cast<uintptr_t>(0), map.end); 713 ASSERT_EQ(0, map.flags); 714 ASSERT_EQ("", map.name); 715} 716 717TEST(libbacktrace, format_test) { 718 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), BACKTRACE_CURRENT_THREAD)); 719 ASSERT_TRUE(backtrace.get() != nullptr); 720 721 backtrace_frame_data_t frame; 722 frame.num = 1; 723 frame.pc = 2; 724 frame.sp = 0; 725 frame.stack_size = 0; 726 frame.func_offset = 0; 727 728 // Check no map set. 729 frame.num = 1; 730#if defined(__LP64__) 731 EXPECT_EQ("#01 pc 0000000000000002 <unknown>", 732#else 733 EXPECT_EQ("#01 pc 00000002 <unknown>", 734#endif 735 backtrace->FormatFrameData(&frame)); 736 737 // Check map name empty, but exists. 738 frame.map.start = 1; 739 frame.map.end = 1; 740#if defined(__LP64__) 741 EXPECT_EQ("#01 pc 0000000000000001 <unknown>", 742#else 743 EXPECT_EQ("#01 pc 00000001 <unknown>", 744#endif 745 backtrace->FormatFrameData(&frame)); 746 747 748 // Check relative pc is set and map name is set. 749 frame.pc = 0x12345679; 750 frame.map.name = "MapFake"; 751 frame.map.start = 1; 752 frame.map.end = 1; 753#if defined(__LP64__) 754 EXPECT_EQ("#01 pc 0000000012345678 MapFake", 755#else 756 EXPECT_EQ("#01 pc 12345678 MapFake", 757#endif 758 backtrace->FormatFrameData(&frame)); 759 760 // Check func_name is set, but no func offset. 761 frame.func_name = "ProcFake"; 762#if defined(__LP64__) 763 EXPECT_EQ("#01 pc 0000000012345678 MapFake (ProcFake)", 764#else 765 EXPECT_EQ("#01 pc 12345678 MapFake (ProcFake)", 766#endif 767 backtrace->FormatFrameData(&frame)); 768 769 // Check func_name is set, and func offset is non-zero. 770 frame.func_offset = 645; 771#if defined(__LP64__) 772 EXPECT_EQ("#01 pc 0000000012345678 MapFake (ProcFake+645)", 773#else 774 EXPECT_EQ("#01 pc 12345678 MapFake (ProcFake+645)", 775#endif 776 backtrace->FormatFrameData(&frame)); 777} 778 779struct map_test_t { 780 uintptr_t start; 781 uintptr_t end; 782}; 783 784bool map_sort(map_test_t i, map_test_t j) { 785 return i.start < j.start; 786} 787 788void VerifyMap(pid_t pid) { 789 char buffer[4096]; 790 snprintf(buffer, sizeof(buffer), "/proc/%d/maps", pid); 791 792 FILE* map_file = fopen(buffer, "r"); 793 ASSERT_TRUE(map_file != nullptr); 794 std::vector<map_test_t> test_maps; 795 while (fgets(buffer, sizeof(buffer), map_file)) { 796 map_test_t map; 797 ASSERT_EQ(2, sscanf(buffer, "%" SCNxPTR "-%" SCNxPTR " ", &map.start, &map.end)); 798 test_maps.push_back(map); 799 } 800 fclose(map_file); 801 std::sort(test_maps.begin(), test_maps.end(), map_sort); 802 803 std::unique_ptr<BacktraceMap> map(BacktraceMap::Create(pid)); 804 805 // Basic test that verifies that the map is in the expected order. 806 std::vector<map_test_t>::const_iterator test_it = test_maps.begin(); 807 for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) { 808 ASSERT_TRUE(test_it != test_maps.end()); 809 ASSERT_EQ(test_it->start, it->start); 810 ASSERT_EQ(test_it->end, it->end); 811 ++test_it; 812 } 813 ASSERT_TRUE(test_it == test_maps.end()); 814} 815 816TEST(libbacktrace, verify_map_remote) { 817 pid_t pid; 818 819 if ((pid = fork()) == 0) { 820 while (true) { 821 } 822 _exit(0); 823 } 824 ASSERT_LT(0, pid); 825 826 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 827 828 // Wait for the process to get to a stopping point. 829 WaitForStop(pid); 830 831 // The maps should match exactly since the forked process has been paused. 832 VerifyMap(pid); 833 834 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 835 836 kill(pid, SIGKILL); 837 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 838} 839 840void* ThreadReadTest(void* data) { 841 thread_t* thread_data = reinterpret_cast<thread_t*>(data); 842 843 thread_data->tid = gettid(); 844 845 // Create two map pages. 846 // Mark the second page as not-readable. 847 size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE)); 848 uint8_t* memory; 849 if (posix_memalign(reinterpret_cast<void**>(&memory), pagesize, 2 * pagesize) != 0) { 850 return reinterpret_cast<void*>(-1); 851 } 852 853 if (mprotect(&memory[pagesize], pagesize, PROT_NONE) != 0) { 854 return reinterpret_cast<void*>(-1); 855 } 856 857 // Set up a simple pattern in memory. 858 for (size_t i = 0; i < pagesize; i++) { 859 memory[i] = i; 860 } 861 862 thread_data->data = memory; 863 864 // Tell the caller it's okay to start reading memory. 865 android_atomic_acquire_store(1, &thread_data->state); 866 867 // Loop waiting for the caller to finish reading the memory. 868 while (thread_data->state) { 869 } 870 871 // Re-enable read-write on the page so that we don't crash if we try 872 // and access data on this page when freeing the memory. 873 if (mprotect(&memory[pagesize], pagesize, PROT_READ | PROT_WRITE) != 0) { 874 return reinterpret_cast<void*>(-1); 875 } 876 free(memory); 877 878 android_atomic_acquire_store(1, &thread_data->state); 879 880 return nullptr; 881} 882 883void RunReadTest(Backtrace* backtrace, uintptr_t read_addr) { 884 size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE)); 885 886 // Create a page of data to use to do quick compares. 887 uint8_t* expected = new uint8_t[pagesize]; 888 for (size_t i = 0; i < pagesize; i++) { 889 expected[i] = i; 890 } 891 uint8_t* data = new uint8_t[2*pagesize]; 892 // Verify that we can only read one page worth of data. 893 size_t bytes_read = backtrace->Read(read_addr, data, 2 * pagesize); 894 ASSERT_EQ(pagesize, bytes_read); 895 ASSERT_TRUE(memcmp(data, expected, pagesize) == 0); 896 897 // Verify unaligned reads. 898 for (size_t i = 1; i < sizeof(word_t); i++) { 899 bytes_read = backtrace->Read(read_addr + i, data, 2 * sizeof(word_t)); 900 ASSERT_EQ(2 * sizeof(word_t), bytes_read); 901 ASSERT_TRUE(memcmp(data, &expected[i], 2 * sizeof(word_t)) == 0) 902 << "Offset at " << i << " failed"; 903 } 904 delete data; 905 delete expected; 906} 907 908TEST(libbacktrace, thread_read) { 909 pthread_attr_t attr; 910 pthread_attr_init(&attr); 911 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 912 pthread_t thread; 913 thread_t thread_data = { 0, 0, 0, nullptr }; 914 ASSERT_TRUE(pthread_create(&thread, &attr, ThreadReadTest, &thread_data) == 0); 915 916 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 10)); 917 918 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), thread_data.tid)); 919 ASSERT_TRUE(backtrace.get() != nullptr); 920 921 RunReadTest(backtrace.get(), reinterpret_cast<uintptr_t>(thread_data.data)); 922 923 android_atomic_acquire_store(0, &thread_data.state); 924 925 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 10)); 926} 927 928volatile uintptr_t g_ready = 0; 929volatile uintptr_t g_addr = 0; 930 931void ForkedReadTest() { 932 // Create two map pages. 933 size_t pagesize = static_cast<size_t>(sysconf(_SC_PAGE_SIZE)); 934 uint8_t* memory; 935 if (posix_memalign(reinterpret_cast<void**>(&memory), pagesize, 2 * pagesize) != 0) { 936 perror("Failed to allocate memory\n"); 937 exit(1); 938 } 939 940 // Mark the second page as not-readable. 941 if (mprotect(&memory[pagesize], pagesize, PROT_NONE) != 0) { 942 perror("Failed to mprotect memory\n"); 943 exit(1); 944 } 945 946 // Set up a simple pattern in memory. 947 for (size_t i = 0; i < pagesize; i++) { 948 memory[i] = i; 949 } 950 951 g_addr = reinterpret_cast<uintptr_t>(memory); 952 g_ready = 1; 953 954 while (1) { 955 usleep(US_PER_MSEC); 956 } 957} 958 959TEST(libbacktrace, process_read) { 960 pid_t pid; 961 if ((pid = fork()) == 0) { 962 ForkedReadTest(); 963 exit(0); 964 } 965 ASSERT_NE(-1, pid); 966 967 bool test_executed = false; 968 uint64_t start = NanoTime(); 969 while (1) { 970 if (ptrace(PTRACE_ATTACH, pid, 0, 0) == 0) { 971 WaitForStop(pid); 972 973 std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, pid)); 974 975 uintptr_t read_addr; 976 size_t bytes_read = backtrace->Read(reinterpret_cast<uintptr_t>(&g_ready), 977 reinterpret_cast<uint8_t*>(&read_addr), 978 sizeof(uintptr_t)); 979 ASSERT_EQ(sizeof(uintptr_t), bytes_read); 980 if (read_addr) { 981 // The forked process is ready to be read. 982 bytes_read = backtrace->Read(reinterpret_cast<uintptr_t>(&g_addr), 983 reinterpret_cast<uint8_t*>(&read_addr), 984 sizeof(uintptr_t)); 985 ASSERT_EQ(sizeof(uintptr_t), bytes_read); 986 987 RunReadTest(backtrace.get(), read_addr); 988 989 test_executed = true; 990 break; 991 } 992 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 993 } 994 if ((NanoTime() - start) > 5 * NS_PER_SEC) { 995 break; 996 } 997 usleep(US_PER_MSEC); 998 } 999 kill(pid, SIGKILL); 1000 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 1001 1002 ASSERT_TRUE(test_executed); 1003} 1004 1005#if defined(ENABLE_PSS_TESTS) 1006#include "GetPss.h" 1007 1008#define MAX_LEAK_BYTES 32*1024UL 1009 1010void CheckForLeak(pid_t pid, pid_t tid) { 1011 // Do a few runs to get the PSS stable. 1012 for (size_t i = 0; i < 100; i++) { 1013 Backtrace* backtrace = Backtrace::Create(pid, tid); 1014 ASSERT_TRUE(backtrace != nullptr); 1015 ASSERT_TRUE(backtrace->Unwind(0)); 1016 delete backtrace; 1017 } 1018 size_t stable_pss = GetPssBytes(); 1019 ASSERT_TRUE(stable_pss != 0); 1020 1021 // Loop enough that even a small leak should be detectable. 1022 for (size_t i = 0; i < 4096; i++) { 1023 Backtrace* backtrace = Backtrace::Create(pid, tid); 1024 ASSERT_TRUE(backtrace != nullptr); 1025 ASSERT_TRUE(backtrace->Unwind(0)); 1026 delete backtrace; 1027 } 1028 size_t new_pss = GetPssBytes(); 1029 ASSERT_TRUE(new_pss != 0); 1030 size_t abs_diff = (new_pss > stable_pss) ? new_pss - stable_pss : stable_pss - new_pss; 1031 // As long as the new pss is within a certain amount, consider everything okay. 1032 ASSERT_LE(abs_diff, MAX_LEAK_BYTES); 1033} 1034 1035TEST(libbacktrace, check_for_leak_local) { 1036 CheckForLeak(BACKTRACE_CURRENT_PROCESS, BACKTRACE_CURRENT_THREAD); 1037} 1038 1039TEST(libbacktrace, check_for_leak_local_thread) { 1040 thread_t thread_data = { 0, 0, 0, nullptr }; 1041 pthread_t thread; 1042 ASSERT_TRUE(pthread_create(&thread, nullptr, ThreadLevelRun, &thread_data) == 0); 1043 1044 // Wait up to 2 seconds for the tid to be set. 1045 ASSERT_TRUE(WaitForNonZero(&thread_data.state, 2)); 1046 1047 CheckForLeak(BACKTRACE_CURRENT_PROCESS, thread_data.tid); 1048 1049 // Tell the thread to exit its infinite loop. 1050 android_atomic_acquire_store(0, &thread_data.state); 1051 1052 ASSERT_TRUE(pthread_join(thread, nullptr) == 0); 1053} 1054 1055TEST(libbacktrace, check_for_leak_remote) { 1056 pid_t pid; 1057 1058 if ((pid = fork()) == 0) { 1059 while (true) { 1060 } 1061 _exit(0); 1062 } 1063 ASSERT_LT(0, pid); 1064 1065 ASSERT_TRUE(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); 1066 1067 // Wait for the process to get to a stopping point. 1068 WaitForStop(pid); 1069 1070 CheckForLeak(pid, BACKTRACE_CURRENT_THREAD); 1071 1072 ASSERT_TRUE(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); 1073 1074 kill(pid, SIGKILL); 1075 ASSERT_EQ(waitpid(pid, nullptr, 0), pid); 1076} 1077#endif 1078