1 #ifndef JEMALLOC_INTERNAL_ATOMIC_H 2 #define JEMALLOC_INTERNAL_ATOMIC_H 3 4 #define ATOMIC_INLINE static inline 5 6 #if defined(JEMALLOC_GCC_ATOMIC_ATOMICS) 7 # include "jemalloc/internal/atomic_gcc_atomic.h" 8 #elif defined(JEMALLOC_GCC_SYNC_ATOMICS) 9 # include "jemalloc/internal/atomic_gcc_sync.h" 10 #elif defined(_MSC_VER) 11 # include "jemalloc/internal/atomic_msvc.h" 12 #elif defined(JEMALLOC_C11_ATOMICS) 13 # include "jemalloc/internal/atomic_c11.h" 14 #else 15 # error "Don't have atomics implemented on this platform." 16 #endif 17 18 /* 19 * This header gives more or less a backport of C11 atomics. The user can write 20 * JEMALLOC_GENERATE_ATOMICS(type, short_type, lg_sizeof_type); to generate 21 * counterparts of the C11 atomic functions for type, as so: 22 * JEMALLOC_GENERATE_ATOMICS(int *, pi, 3); 23 * and then write things like: 24 * int *some_ptr; 25 * atomic_pi_t atomic_ptr_to_int; 26 * atomic_store_pi(&atomic_ptr_to_int, some_ptr, ATOMIC_RELAXED); 27 * int *prev_value = atomic_exchange_pi(&ptr_to_int, NULL, ATOMIC_ACQ_REL); 28 * assert(some_ptr == prev_value); 29 * and expect things to work in the obvious way. 30 * 31 * Also included (with naming differences to avoid conflicts with the standard 32 * library): 33 * atomic_fence(atomic_memory_order_t) (mimics C11's atomic_thread_fence). 34 * ATOMIC_INIT (mimics C11's ATOMIC_VAR_INIT). 35 */ 36 37 /* 38 * Pure convenience, so that we don't have to type "atomic_memory_order_" 39 * quite so often. 40 */ 41 #define ATOMIC_RELAXED atomic_memory_order_relaxed 42 #define ATOMIC_ACQUIRE atomic_memory_order_acquire 43 #define ATOMIC_RELEASE atomic_memory_order_release 44 #define ATOMIC_ACQ_REL atomic_memory_order_acq_rel 45 #define ATOMIC_SEQ_CST atomic_memory_order_seq_cst 46 47 /* 48 * Not all platforms have 64-bit atomics. If we do, this #define exposes that 49 * fact. 50 */ 51 #if (LG_SIZEOF_PTR == 3 || LG_SIZEOF_INT == 3) 52 # define JEMALLOC_ATOMIC_U64 53 #endif 54 55 JEMALLOC_GENERATE_ATOMICS(void *, p, LG_SIZEOF_PTR) 56 57 /* 58 * There's no actual guarantee that sizeof(bool) == 1, but it's true on the only 59 * platform that actually needs to know the size, MSVC. 60 */ 61 JEMALLOC_GENERATE_ATOMICS(bool, b, 0) 62 63 JEMALLOC_GENERATE_INT_ATOMICS(unsigned, u, LG_SIZEOF_INT) 64 65 JEMALLOC_GENERATE_INT_ATOMICS(size_t, zu, LG_SIZEOF_PTR) 66 67 JEMALLOC_GENERATE_INT_ATOMICS(ssize_t, zd, LG_SIZEOF_PTR) 68 69 JEMALLOC_GENERATE_INT_ATOMICS(uint32_t, u32, 2) 70 71 #ifdef JEMALLOC_ATOMIC_U64 72 JEMALLOC_GENERATE_INT_ATOMICS(uint64_t, u64, 3) 73 #endif 74 75 #undef ATOMIC_INLINE 76 77 #endif /* JEMALLOC_INTERNAL_ATOMIC_H */ 78