| // Copyright (C) 2006-2022 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING3. If not see |
| // <http://www.gnu.org/licenses/>. |
| |
| // 20.6.6.2 Template class shared_ptr [util.smartptr.shared] |
| |
| // { dg-do run } |
| // { dg-additional-options "-pthread" { target pthread } } |
| // { dg-add-options libatomic } |
| // { dg-require-effective-target c++11 } |
| // { dg-require-gthreads "" } |
| // { dg-require-cstdint "" } |
| |
| #include <memory> |
| #include <random> |
| #include <vector> |
| #include <iostream> |
| #include <cstdlib> |
| #include <thread> |
| #include <atomic> |
| #include <functional> |
| #include <testsuite_hooks.h> |
| |
| #ifdef _GLIBCXX_HAVE_UNISTD_H |
| #include <unistd.h> // To test for _POSIX_THREAD_PRIORITY_SCHEDULING |
| #endif |
| |
| /* This (brute-force) tests the atomicity and thus thread safety of the |
| * shared_ptr <- weak_ptr |
| * assignment operation by allocating a test object, retrieving a weak |
| * reference to it, and letting a number of threads repeatedly create strong |
| * references from the weak reference. |
| * Specifically, this tests the function _Sp_counted_base<true>::add_ref_lock() |
| */ |
| |
| |
| const unsigned int HAMMER_MAX_THREADS = 10; |
| const unsigned int POOL_SIZE = 1000; |
| const unsigned long HAMMER_REPEAT = 100000; |
| const unsigned long KILL_ONE_IN = 1000; |
| |
| struct A |
| { |
| static std::atomic<int> counter; |
| A() { counter.fetch_add(1, std::memory_order_relaxed); } |
| ~A() { counter.fetch_sub(1, std::memory_order_relaxed); } |
| }; |
| |
| std::atomic<int> A::counter{0}; |
| |
| using std::_S_mutex; |
| |
| typedef std::__shared_ptr<A, _S_mutex> sp_A_t; |
| typedef std::__weak_ptr<A, _S_mutex> wp_A_t; |
| |
| typedef std::vector<sp_A_t> sp_vector_t; |
| typedef std::vector<wp_A_t> wp_vector_t; |
| |
| struct shared_and_weak_pools |
| { |
| sp_vector_t& shared_pool; |
| wp_vector_t& weak_pool; |
| |
| shared_and_weak_pools(sp_vector_t& _shared_pool, wp_vector_t& _weak_pool) |
| : shared_pool(_shared_pool), weak_pool(_weak_pool) |
| { } |
| }; |
| |
| void thread_hammer_and_kill(shared_and_weak_pools& pools) |
| { |
| std::mt19937 urbg; |
| std::uniform_int_distribution<> dist(0, KILL_ONE_IN - 1); |
| |
| sp_vector_t::iterator cur_shared = pools.shared_pool.begin(); |
| wp_vector_t::iterator cur_weak = pools.weak_pool.begin(); |
| |
| for (unsigned int i = 0; i < HAMMER_REPEAT; ++i) |
| { |
| try |
| { |
| sp_A_t strong(*cur_weak); |
| } |
| catch (std::bad_weak_ptr& exception) |
| { |
| ++cur_weak; |
| if (cur_weak == pools.weak_pool.end()) |
| break; |
| } |
| |
| if (dist(urbg) == 0) |
| { |
| cur_shared->reset(); |
| ++cur_shared; |
| } |
| } |
| } |
| |
| void thread_hammer(wp_vector_t& weak_pool) |
| { |
| wp_vector_t::iterator cur_weak = weak_pool.begin(); |
| |
| for (unsigned int i = 0; i < HAMMER_REPEAT; ++i) |
| { |
| try |
| { |
| sp_A_t strong(*cur_weak); |
| } |
| catch (std::bad_weak_ptr& exception) |
| { |
| ++cur_weak; |
| if (cur_weak == weak_pool.end()) |
| break; |
| } |
| } |
| } |
| |
| void |
| test01() |
| { |
| sp_vector_t obj_pool(POOL_SIZE); |
| |
| for(auto& obj : obj_pool) |
| obj.reset(new A); |
| |
| // Obtain weak references. |
| std::vector<wp_vector_t> weak_pool(HAMMER_MAX_THREADS, wp_vector_t(obj_pool.begin(), obj_pool.end())); |
| |
| // Launch threads with pointer to weak reference. |
| std::thread threads[HAMMER_MAX_THREADS]; |
| #if defined(__sun) && defined(__svr4__) && _XOPEN_VERSION >= 500 |
| pthread_setconcurrency (HAMMER_MAX_THREADS); |
| #endif |
| |
| shared_and_weak_pools pools(obj_pool, weak_pool[0]); |
| threads[0] = std::thread(thread_hammer_and_kill, std::ref(pools)); |
| for (unsigned int worker = 1; worker < HAMMER_MAX_THREADS; worker++) |
| threads[worker] = std::thread(thread_hammer, std::ref(weak_pool[worker])); |
| |
| // Wait for threads to complete, then check integrity of reference. |
| for (auto& thread : threads) |
| thread.join(); |
| |
| obj_pool.clear(); |
| |
| VERIFY( A::counter == 0 ); |
| } |
| |
| int |
| main() |
| { |
| test01(); |
| return 0; |
| } |