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The lock pool mutexes are now statically initialized. Fixes #9466.

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This commit is contained in:
Andrey Semashev
2013-12-14 19:44:23 +04:00
parent 6ef10a2d40
commit 9ded906200
2 changed files with 64 additions and 24 deletions
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64
src/lockpool.cpp
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@@ -1,8 +1,18 @@
#include <cstddef>
#include <boost/config.hpp>
#include <boost/assert.hpp>
#include <boost/atomic.hpp>
#if !defined(BOOST_ATOMIC_FLAG_LOCK_FREE) || BOOST_ATOMIC_FLAG_LOCK_FREE != 2
#if !defined(BOOST_HAS_PTHREADS)
#error Boost.Atomic: Unsupported target platform, POSIX threads are required when native atomic operations are not available
#endif
#include <pthread.h>
#define BOOST_ATOMIC_USE_PTHREAD
#endif
// Copyright (c) 2011 Helge Bahmann
// Copyright (c) 2013 Andrey Semashev
//
// Distributed under the Boost Software License, Version 1.0.
// See accompanying file LICENSE_1_0.txt or copy at
@@ -15,7 +25,7 @@ namespace detail {
namespace {
// This seems to be the maximum across all modern CPUs
// NOTE: This constant is made as a macro because some compilers (gcc 4.4 for one) don't allow enums or regular constants in alignment attributes
// NOTE: This constant is made as a macro because some compilers (gcc 4.4 for one) don't allow enums or namespace scope constants in alignment attributes
#define BOOST_ATOMIC_CACHE_LINE_SIZE 64
template< unsigned int N >
@@ -30,26 +40,64 @@ struct padding< 0 >
struct BOOST_ALIGNMENT(BOOST_ATOMIC_CACHE_LINE_SIZE) padded_lock
{
lockpool::lock_type lock;
#if defined(BOOST_ATOMIC_USE_PTHREAD)
typedef pthread_mutex_t lock_type;
#else
typedef lockpool::lock_type lock_type;
#endif
lock_type lock;
// The additional padding is needed to avoid false sharing between locks
enum { padding_size = (sizeof(lockpool::lock_type) <= BOOST_ATOMIC_CACHE_LINE_SIZE ?
(BOOST_ATOMIC_CACHE_LINE_SIZE - sizeof(lockpool::lock_type)) :
(BOOST_ATOMIC_CACHE_LINE_SIZE - sizeof(lockpool::lock_type) % BOOST_ATOMIC_CACHE_LINE_SIZE)) };
enum { padding_size = (sizeof(lock_type) <= BOOST_ATOMIC_CACHE_LINE_SIZE ?
(BOOST_ATOMIC_CACHE_LINE_SIZE - sizeof(lock_type)) :
(BOOST_ATOMIC_CACHE_LINE_SIZE - sizeof(lock_type) % BOOST_ATOMIC_CACHE_LINE_SIZE)) };
padding< padding_size > pad;
};
static padded_lock lock_pool_[41];
static padded_lock lock_pool_[41]
#if defined(BOOST_ATOMIC_USE_PTHREAD)
=
{
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, PTHREAD_MUTEX_INITIALIZER,
PTHREAD_MUTEX_INITIALIZER
}
#endif
;
} // namespace
#if !defined(BOOST_ATOMIC_USE_PTHREAD)
// NOTE: This function must NOT be inline. Otherwise MSVC 9 will sometimes generate broken code for modulus operation which result in crashes.
BOOST_ATOMIC_DECL lockpool::lock_type& lockpool::get_lock_for(const volatile void* addr)
{
std::size_t index = reinterpret_cast<std::size_t>(addr) % (sizeof(lock_pool_) / sizeof(*lock_pool_));
std::size_t index = reinterpret_cast< std::size_t >(addr) % (sizeof(lock_pool_) / sizeof(*lock_pool_));
return lock_pool_[index].lock;
}
#else // !defined(BOOST_ATOMIC_USE_PTHREAD)
BOOST_ATOMIC_DECL lockpool::scoped_lock::scoped_lock(const volatile void* addr) :
lock_(&lock_pool_[reinterpret_cast< std::size_t >(addr) % (sizeof(lock_pool_) / sizeof(*lock_pool_))].lock)
{
BOOST_VERIFY(pthread_mutex_lock(static_cast< pthread_mutex_t* >(lock_)) == 0);
}
BOOST_ATOMIC_DECL lockpool::scoped_lock::~scoped_lock()
{
BOOST_VERIFY(pthread_mutex_unlock(static_cast< pthread_mutex_t* >(lock_)) == 0);
}
}
#endif // !defined(BOOST_ATOMIC_USE_PTHREAD)
} // namespace detail
} // namespace atomics
} // namespace boost