libstdc++-v3/testsuite/23_containers/vector/debug/multithreaded_swap.cc

   1 // { dg-do run { target *-*-freebsd* *-*-netbsd* *-*-linux* *-*-gnu* *-*-solaris* *-*-cygwin *-*-darwin* } }
   2 // { dg-options " -std=gnu++0x -pthread" { target *-*-freebsd* *-*-netbsd* *-*-linux* *-*-gnu* } }
   3 // { dg-options " -std=gnu++0x -pthreads" { target *-*-solaris* } }
   4 // { dg-options " -std=gnu++0x " { target *-*-cygwin *-*-darwin* } }
   5 // { dg-require-cstdint "" }
   6 // { dg-require-gthreads "" }
   7 // { dg-require-debug-mode "" }
   8 // Copyright (C) 2010-2013 Free Software Foundation, Inc.
   9 //
  10 // This file is part of the GNU ISO C++ Library.  This library is free
  11 // software; you can redistribute it and/or modify it under the
  12 // terms of the GNU General Public License as published by the
  13 // Free Software Foundation; either version 3, or (at your option)
  14 // any later version.
  15 //
  16 // This library is distributed in the hope that it will be useful,
  17 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 // GNU General Public License for more details.
  20 //
  21 // You should have received a copy of the GNU General Public License along
  22 // with this library; see the file COPYING3.  If not see
  23 // <http://www.gnu.org/licenses/>.
  24 //
  25
  26 // This test check for potential deadlock when swaping sequences in debug
  27 // mode as it requires acquiring 2 locks at the same time.
  28
  29 #include <vector>
  30 #include <thread>
  31 #include <functional>
  32 #include <testsuite_hooks.h>
  33
  34 // The following function mimic the one in src/debug.cc to associate a mutex
  35 // to a given safe sequence instance.
  36 size_t
  37 get_index(std::vector<int>& v)
  38 {
  39   const size_t mask = 0xf;
  40   // We have to check the address of the internal safe sequence that starts
  41   // after the normal vector memory footprint that is to say a 3 pointers
  42   // offset:
  43   void* __address = reinterpret_cast<char*>(&v) + 3 * sizeof(void*);
  44   return std::_Hash_impl::hash(__address) & mask;
  45 }
  46
  47 void test01()
  48 {
  49   using namespace std;
  50   bool test __attribute__((unused)) = true;
  51   vector<int> v1, v2;
  52   vector<shared_ptr<vector<int> > > vs;
  53   vector<int> *pv3 = 0, *pv4 = 0;
  54   const int nb_attempts = 100;
  55   for (int i = 0; i != nb_attempts; ++i)
  56     {
  57       vs.push_back(shared_ptr<vector<int> >(new vector<int>()));
  58       if (!pv3)
  59         {
  60           if (get_index(*vs.back()) == get_index(v1))
  61             pv3 = vs.back().get();
  62         }
  63       else if (!pv4)
  64         {
  65           if (get_index(*vs.back()) == get_index(v2))
  66             {
  67               pv4 = vs.back().get();
  68               break;
  69             }
  70         }
  71     }
  72
  73   if (!pv3 || !pv4)
  74     // Maybe an other time...
  75     return;
  76
  77   vector<int> &v3 = *pv3, &v4 = *pv4;
  78
  79   // v1 and v3 shares the same mutex instance, like v2 and v4
  80   // thread t1 lock v1 and v2
  81   thread t1([&v1, &v2]()
  82     {
  83       for (int i = 0; i != 1000; ++i)
  84         v1.swap(v2);
  85     });
  86   // thread t2 lock v4 and v3
  87   thread t2([&v3, &v4]()
  88     {
  89       for (int i = 0; i != 1000; ++i)
  90         v4.swap(v3);
  91     });
  92   t2.join();
  93   t1.join();
  94 }
  95
  96 int main()
  97 {
  98   test01();
  99   return 0;
 100 }