compiler-rt/lib/sanitizer_common/tests/sanitizer_stoptheworld_testlib.cpp

   1 //===-- sanitizer_stoptheworld_testlib.cpp --------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 // Dynamic library to test StopTheWorld functionality.
   9 // When loaded with LD_PRELOAD, it will periodically suspend all threads.
  10 //===----------------------------------------------------------------------===//
  11 /* Usage:
  12 clang++ -fno-exceptions -g -fPIC -I. \
  13  sanitizer_common/tests/sanitizer_stoptheworld_testlib.cpp \
  14  sanitizer_common/sanitizer_*.cpp -shared -lpthread -o teststoptheworld.so
  15 LD_PRELOAD=`pwd`/teststoptheworld.so /your/app
  16 */
  17
  18 #include "sanitizer_common/sanitizer_platform.h"
  19 #if SANITIZER_LINUX
  20
  21 #include <dlfcn.h>
  22 #include <stddef.h>
  23 #include <stdio.h>
  24 #include <pthread.h>
  25 #include <unistd.h>
  26
  27 #include "sanitizer_common/sanitizer_stoptheworld.h"
  28
  29 namespace {
  30 const uptr kSuspendDuration = 3;
  31 const uptr kRunDuration = 3;
  32
  33 void Callback(const SuspendedThreadsList &suspended_threads_list,
  34               void *argument) {
  35   sleep(kSuspendDuration);
  36 }
  37
  38 void *SuspenderThread(void *argument) {
  39   while (true) {
  40     sleep(kRunDuration);
  41     StopTheWorld(Callback, NULL);
  42   }
  43   return NULL;
  44 }
  45
  46 __attribute__((constructor)) void StopTheWorldTestLibConstructor(void) {
  47   pthread_t thread_id;
  48   pthread_create(&thread_id, NULL, SuspenderThread, NULL);
  49 }
  50 }  // namespace
  51
  52 #endif  // SANITIZER_LINUX