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Re: default_weaktoshared timeouts
On 2 April 2010 14:12, Jack Howarth wrote:
>
> Paolo,
> ? I don't believe this occurs with the x86_64-apple-darwin10
> target but only with i686-apple-darwin10 so it may well be
> a bug in the 32-bit linker on darwin. I'll try benchmarking the
> actual linkage command at both 32-bit and 64-bit to see if
> it can be reproduced. If so, I'll file a radar bug report.
It's running the test that is timing out rather than the linker
command. It would be helpful to know if the test is actually stuck,
or just running so slowly it times out and gets killed.
Can you reproduce it just by building the attached file with
-std=gnu++0x and running it in a loop? This is just a standalone copy
of the testsuite that doesn't need the testsuite_hooks.h header. If
it is getting stuck please CC me on a bug report.
Thanks,
Jonathan
// Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation
//
// 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 { target *-*-freebsd* *-*-netbsd* *-*-linux* *-*-solaris* *-*-cygwin *-*-darwin* alpha*-*-osf* mips-sgi-irix6* } }
// { dg-options "-pthread -std=gnu++0x" { target *-*-freebsd* *-*-netbsd* *-*-linux* alpha*-*-osf* mips-sgi-irix6* } }
// { dg-options "-pthreads -std=gnu++0x" { target *-*-solaris* } }
// { dg-options " -std=gnu++0x " { target *-*-cygwin *-*-darwin* } }
#include <memory>
#include <random>
#include <vector>
#include <assert.h>
#define VERIFY assert
#include <iostream>
#include <cstdlib>
#include <pthread.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 _Atomic_word counter;
A()
{
__gnu_cxx::__atomic_add(&counter, 1);
}
~A()
{
__gnu_cxx::__atomic_add(&counter, -1);
}
};
_Atomic_word A::counter = 0;
typedef std::shared_ptr<A> sp_A_t;
typedef std::weak_ptr<A> 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(void* opaque_pools)
{
shared_and_weak_pools& pools = *static_cast<shared_and_weak_pools*>(opaque_pools);
// Using the same parameters as in the RNG test cases.
std::mersenne_twister_engine<
unsigned long, 32, 624, 397, 31,
0x9908b0dful, 11,
0xfffffffful, 7,
0x9d2c5680ul, 15,
0xefc60000ul, 18, 1812433253ul> rng;
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 (rng() % KILL_ONE_IN == 0)
{
cur_shared->reset();
++cur_shared;
}
}
return 0;
}
void* thread_hammer(void* opaque_weak)
{
wp_vector_t& weak_pool = *static_cast<wp_vector_t*>(opaque_weak);
// Using the same parameters as in the RNG test cases.
std::mersenne_twister_engine<
unsigned long, 32, 624, 397, 31,
0x9908b0dful, 11,
0xfffffffful, 7,
0x9d2c5680ul, 15,
0xefc60000ul, 18, 1812433253ul> rng;
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;
}
}
return 0;
}
int
test01()
{
bool test __attribute__((unused)) = true;
sp_vector_t obj_pool(POOL_SIZE);
for(sp_vector_t::iterator cur = obj_pool.begin(); cur != obj_pool.end(); ++cur)
{
cur->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.
pthread_t threads[HAMMER_MAX_THREADS];
#if defined(__sun) && defined(__svr4__) && _XOPEN_VERSION >= 500
pthread_setconcurrency (HAMMER_MAX_THREADS);
#endif
pthread_attr_t tattr;
pthread_attr_init(&tattr);
shared_and_weak_pools pools(obj_pool, weak_pool[0]);
pthread_create(threads, &tattr, thread_hammer_and_kill, static_cast<void*>(&pools));
for (unsigned int worker = 1; worker < HAMMER_MAX_THREADS; worker++)
{
if (pthread_create(&threads[worker], &tattr,
thread_hammer, static_cast<void*>(&weak_pool[worker])))
std::abort();
}
// Wait for threads to complete, then check integrity of reference.
void* status;
for (unsigned int worker = 0; worker < HAMMER_MAX_THREADS; worker++)
{
if (pthread_join(threads[worker], &status))
std::abort();
}
obj_pool.clear();
VERIFY( A::counter == 0 );
return 0;
}
int
main()
{
test01();
return 0;
}