diff options
Diffstat (limited to 'libs/atomic/src/lockpool.cpp')
| -rw-r--r-- | libs/atomic/src/lockpool.cpp | 69 |
1 files changed, 38 insertions, 31 deletions
diff --git a/libs/atomic/src/lockpool.cpp b/libs/atomic/src/lockpool.cpp index 13269a160..0e059c2ca 100644 --- a/libs/atomic/src/lockpool.cpp +++ b/libs/atomic/src/lockpool.cpp @@ -40,46 +40,49 @@ namespace { // 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 > -struct padding -{ - char data[N]; -}; -template< > -struct padding< 0 > +#if defined(BOOST_ATOMIC_USE_PTHREAD) +typedef pthread_mutex_t lock_type; +#else +typedef atomics::detail::operations< 1u, false > lock_operations; +typedef lock_operations::storage_type lock_type; +#endif + +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)) }; +template< unsigned int PaddingSize > struct BOOST_ALIGNMENT(BOOST_ATOMIC_CACHE_LINE_SIZE) padded_lock { -#if defined(BOOST_ATOMIC_USE_PTHREAD) - typedef pthread_mutex_t lock_type; -#else - typedef atomics::detail::operations< 1u, false > operations; - typedef operations::storage_type lock_type; -#endif - lock_type lock; // The additional padding is needed to avoid false sharing between locks - 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; + char padding[PaddingSize]; }; -static padded_lock g_lock_pool[41] +template< > +struct BOOST_ALIGNMENT(BOOST_ATOMIC_CACHE_LINE_SIZE) padded_lock< 0u > +{ + lock_type lock; +}; + +typedef padded_lock< padding_size > padded_lock_t; + +static padded_lock_t g_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 + { 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 ; @@ -93,15 +96,19 @@ static padded_lock g_lock_pool[41] BOOST_ATOMIC_DECL lockpool::scoped_lock::scoped_lock(const volatile void* addr) BOOST_NOEXCEPT : m_lock(&g_lock_pool[reinterpret_cast< std::size_t >(addr) % (sizeof(g_lock_pool) / sizeof(*g_lock_pool))].lock) { - while (padded_lock::operations::test_and_set(*static_cast< padded_lock::lock_type* >(m_lock), memory_order_acquire)) + while (lock_operations::test_and_set(*static_cast< lock_type* >(m_lock), memory_order_acquire)) { - atomics::detail::pause(); + do + { + atomics::detail::pause(); + } + while (!!lock_operations::load(*static_cast< lock_type* >(m_lock), memory_order_relaxed)); } } BOOST_ATOMIC_DECL lockpool::scoped_lock::~scoped_lock() BOOST_NOEXCEPT { - padded_lock::operations::clear(*static_cast< padded_lock::lock_type* >(m_lock), memory_order_release); + lock_operations::clear(*static_cast< lock_type* >(m_lock), memory_order_release); } BOOST_ATOMIC_DECL void signal_fence() BOOST_NOEXCEPT; |