diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/internal/refcount.h | 73 |
1 files changed, 62 insertions, 11 deletions
diff --git a/include/internal/refcount.h b/include/internal/refcount.h index c1663a0f83..75d70a6418 100644 --- a/include/internal/refcount.h +++ b/include/internal/refcount.h @@ -1,5 +1,5 @@ /* - * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy @@ -18,26 +18,36 @@ # if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \ && !defined(__STDC_NO_ATOMICS__) -# include <stdatomic.h> -# define HAVE_C11_ATOMICS +# include <stdatomic.h> +# define HAVE_C11_ATOMICS # endif # if defined(HAVE_C11_ATOMICS) && defined(ATOMIC_INT_LOCK_FREE) \ && ATOMIC_INT_LOCK_FREE > 0 -# define HAVE_ATOMICS 1 +# define HAVE_ATOMICS 1 typedef _Atomic int CRYPTO_REF_COUNT; -static ossl_inline int CRYPTO_UP_REF(_Atomic int *val, int *ret, void *lock) +static inline int CRYPTO_UP_REF(_Atomic int *val, int *ret, void *lock) { *ret = atomic_fetch_add_explicit(val, 1, memory_order_relaxed) + 1; return 1; } -static ossl_inline int CRYPTO_DOWN_REF(_Atomic int *val, int *ret, void *lock) +/* + * Changes to shared structure other than reference counter have to be + * serialized. And any kind of serialization implies a release fence. This + * means that by the time reference counter is decremented all other + * changes are visible on all processors. Hence decrement itself can be + * relaxed. In case it hits zero, object will be destructed. Since it's + * last use of the object, destructor programmer might reason that access + * to mutable members doesn't have to be serialized anymore, which would + * otherwise imply an acquire fence. Hence conditional acquire fence... + */ +static inline int CRYPTO_DOWN_REF(_Atomic int *val, int *ret, void *lock) { - *ret = atomic_fetch_sub_explicit(val, 1, memory_order_release) - 1; + *ret = atomic_fetch_sub_explicit(val, 1, memory_order_relaxed) - 1; if (*ret == 0) atomic_thread_fence(memory_order_acquire); return 1; @@ -45,24 +55,65 @@ static ossl_inline int CRYPTO_DOWN_REF(_Atomic int *val, int *ret, void *lock) # elif defined(__GNUC__) && defined(__ATOMIC_RELAXED) && __GCC_ATOMIC_INT_LOCK_FREE > 0 -# define HAVE_ATOMICS 1 +# define HAVE_ATOMICS 1 typedef int CRYPTO_REF_COUNT; -static ossl_inline int CRYPTO_UP_REF(int *val, int *ret, void *lock) +static __inline__ int CRYPTO_UP_REF(int *val, int *ret, void *lock) { *ret = __atomic_fetch_add(val, 1, __ATOMIC_RELAXED) + 1; return 1; } -static ossl_inline int CRYPTO_DOWN_REF(int *val, int *ret, void *lock) +static __inline__ int CRYPTO_DOWN_REF(int *val, int *ret, void *lock) { - *ret = __atomic_fetch_sub(val, 1, __ATOMIC_RELEASE) - 1; + *ret = __atomic_fetch_sub(val, 1, __ATOMIC_RELAXED) - 1; if (*ret == 0) __atomic_thread_fence(__ATOMIC_ACQUIRE); return 1; } +# elif defined(_MSC_VER) && _MSC_VER>=1200 + +# define HAVE_ATOMICS 1 + +typedef volatile int CRYPTO_REF_COUNT; + +# if (defined(_M_ARM) && _M_ARM>=7) || defined(_M_ARM64) +# include <intrin.h> +# if defined(_M_ARM64) && !defined(_ARM_BARRIER_ISH) +# define _ARM_BARRIER_ISH _ARM64_BARRIER_ISH +# endif + +static __inline int CRYPTO_UP_REF(volatile int *val, int *ret, void *lock) +{ + *ret = _InterlockedExchangeAdd_nf(val, 1) + 1; + return 1; +} + +static __inline int CRYPTO_DOWN_REF(volatile int *val, int *ret, void *lock) +{ + *ret = _InterlockedExchangeAdd_nf(val, -1) - 1; + if (*ret == 0) + __dmb(_ARM_BARRIER_ISH); + return 1; +} +# else +# pragma intrinsic(_InterlockedExchangeAdd) + +static __inline int CRYPTO_UP_REF(volatile int *val, int *ret, void *lock) +{ + *ret = _InterlockedExchangeAdd(val, 1) + 1; + return 1; +} + +static __inline int CRYPTO_DOWN_REF(volatile int *val, int *ret, void *lock) +{ + *ret = _InterlockedExchangeAdd(val, -1) - 1; + return 1; +} +# endif + # else typedef int CRYPTO_REF_COUNT; |