/* Copyright (c) 2017 Red Hat, Inc. This file is part of GlusterFS. This file is licensed to you under your choice of the GNU Lesser General Public License, version 3 or any later version (LGPLv3 or later), or the GNU General Public License, version 2 (GPLv2), in all cases as published by the Free Software Foundation. */ #ifndef _ATOMIC_H #define _ATOMIC_H #include #include #include "glusterfs/locking.h" /* Macros used to join two arguments and generate a new macro name. */ #define GF_ATOMIC_MACRO_1(_macro) _macro #define GF_ATOMIC_MACRO(_base, _name) GF_ATOMIC_MACRO_1(_base##_name) /* There's a problem on 32-bit architectures when we try to use atomic * builtins with 64-bit types. Only way to solve the problem is to use * a mutex to protect the access to the atomic, but we don't want to * use mutexes for other smaller types that could work with the atomic * builtins. * * So on each atomic type we add a field for the mutex if atomic operation * is not supported and a dummy zero size field if it's supported. This way * we can have different atomic types, some with a mutex and some without. * * To define these types, we use two macros: * * GF_ATOMIC_MUTEX_FIELD_0 = char lk[0] * GF_ATOMIC_MUTEX_FILED_1 = gf_lock_t lk * * Both macros define the 'lk' field that will be used in the atomic * structure. One when the atomic is supported by the architecture and * another when not. We need to define the field even if it won't be * used. Otherwise the compiler will return an error. * * Now we need to take the mutex or not depending on the existence of * the mutex field in the structure. To do so we check the size of the * structure, and if it's bigger than uint64_t (all structures with a * mutex will be bigger), we use the mutex-based version. Otherwise we * use the atomic builtin. This check is easily optimized out by the * compiler, leaving a clean and efficient compiled code. */ #define GF_ATOMIC_MUTEX_FIELD_0 char lk[0] #define GF_ATOMIC_MUTEX_FIELD_1 gf_lock_t lk /* We'll use SIZEOF_LONG to determine the architecture. 32-bit machines * will have 4 here, while 64-bit machines will have 8. If additional * needs or restrictions appear on other platforms, these tests can be * extended to handle them. */ /* GF_ATOMIC_SIZE_X macros map each type size to one of the * GF_ATOMIC_MUTEX_FIELD_X macros, depending on detected conditions. */ #if defined(HAVE_ATOMIC_BUILTINS) || defined(HAVE_SYNC_BUILTINS) #define GF_ATOMIC_SIZE_1 GF_ATOMIC_MUTEX_FIELD_0 #define GF_ATOMIC_SIZE_2 GF_ATOMIC_MUTEX_FIELD_0 #define GF_ATOMIC_SIZE_4 GF_ATOMIC_MUTEX_FIELD_0 #if SIZEOF_LONG >= 8 #define GF_ATOMIC_SIZE_8 GF_ATOMIC_MUTEX_FIELD_0 #endif #endif /* HAVE_(ATOMIC|SYNC)_BUILTINS */ /* Any GF_ATOMIC_SIZE_X macro not yet defined will use the mutex version */ #ifndef GF_ATOMIC_SIZE_1 #define GF_ATOMIC_SIZE_1 GF_ATOMIC_MUTEX_FIELD_1 #endif #ifndef GF_ATOMIC_SIZE_2 #define GF_ATOMIC_SIZE_2 GF_ATOMIC_MUTEX_FIELD_1 #endif #ifndef GF_ATOMIC_SIZE_4 #define GF_ATOMIC_SIZE_4 GF_ATOMIC_MUTEX_FIELD_1 #endif #ifndef GF_ATOMIC_SIZE_8 #define GF_ATOMIC_SIZE_8 GF_ATOMIC_MUTEX_FIELD_1 #endif /* This macro is used to define all atomic types supported. First field * represents the size of the type in bytes, and the second one the name. */ #define GF_ATOMIC_TYPE(_size, _name) \ typedef struct _gf_atomic_##_name##_t { \ GF_ATOMIC_MACRO(GF_ATOMIC_SIZE_, _size); \ _name##_t value; \ } gf_atomic_##_name##_t /* The atomic types we support */ GF_ATOMIC_TYPE(1, int8); /* gf_atomic_int8_t */ GF_ATOMIC_TYPE(2, int16); /* gf_atomic_int16_t */ GF_ATOMIC_TYPE(4, int32); /* gf_atomic_int32_t */ GF_ATOMIC_TYPE(8, int64); /* gf_atomic_int64_t */ GF_ATOMIC_TYPE(SIZEOF_LONG, intptr); /* gf_atomic_intptr_t */ GF_ATOMIC_TYPE(1, uint8); /* gf_atomic_uint8_t */ GF_ATOMIC_TYPE(2, uint16); /* gf_atomic_uint16_t */ GF_ATOMIC_TYPE(4, uint32); /* gf_atomic_uint32_t */ GF_ATOMIC_TYPE(8, uint64); /* gf_atomic_uint64_t */ GF_ATOMIC_TYPE(SIZEOF_LONG, uintptr); /* gf_atomic_uintptr_t */ /* Define the default atomic type as int64_t */ #define gf_atomic_t gf_atomic_int64_t /* This macro will choose between the mutex based version and the atomic * builtin version depending on the size of the atomic structure. */ #define GF_ATOMIC_CHOOSE(_atomic, _op, _args...) \ ((sizeof(_atomic) > sizeof(uint64_t)) \ ? ({ \ GF_ATOMIC_MACRO(GF_ATOMIC_LOCK_, _op) \ (_atomic, ##_args); \ }) \ : ({ \ GF_ATOMIC_MACRO(GF_ATOMIC_BASE_, _op) \ (_atomic, ##_args); \ })) /* Macros to implement the mutex-based atomics. */ #define GF_ATOMIC_OP_PREPARE(_atomic, _name) \ typeof(_atomic) *__atomic = &(_atomic); \ gf_lock_t *__lock = (gf_lock_t *)&__atomic->lk; \ LOCK(__lock); \ typeof(__atomic->value) _name = __atomic->value #define GF_ATOMIC_OP_STORE(_value) (__atomic->value = (_value)) #define GF_ATOMIC_OP_RETURN(_value) \ ({ \ UNLOCK(__lock); \ _value; \ }) #define GF_ATOMIC_LOCK_INIT(_atomic, _value) \ do { \ typeof(_atomic) *__atomic = &(_atomic); \ LOCK_INIT((gf_lock_t *)&__atomic->lk); \ __atomic->value = (_value); \ } while (0) #define GF_ATOMIC_LOCK_GET(_atomic) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_ADD(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value += (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_SUB(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value -= (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_AND(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value &= (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_OR(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value |= (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_XOR(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value ^= (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_NAND(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value = ~(__value & (_value))); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_FETCH_ADD(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value + (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_FETCH_SUB(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value - (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_FETCH_AND(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value &(_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_FETCH_OR(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value | (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_FETCH_XOR(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(__value ^ (_value)); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_FETCH_NAND(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(~(__value & (_value))); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_SWAP(_atomic, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ GF_ATOMIC_OP_STORE(_value); \ GF_ATOMIC_OP_RETURN(__value); \ }) #define GF_ATOMIC_LOCK_CMP_SWAP(_atomic, _expected, _value) \ ({ \ GF_ATOMIC_OP_PREPARE(_atomic, __value); \ bool __ret = (__value == (_expected)); \ if (__ret) { \ GF_ATOMIC_OP_STORE(_value); \ } \ GF_ATOMIC_OP_RETURN(__ret); \ }) #if defined(HAVE_ATOMIC_BUILTINS) /* If compiler supports __atomic builtins, we use them. */ #define GF_ATOMIC_BASE_INIT(_atomic, _value) \ __atomic_store_n(&(_atomic).value, (_value), __ATOMIC_RELEASE) #define GF_ATOMIC_BASE_GET(_atomic) \ __atomic_load_n(&(_atomic).value, __ATOMIC_ACQUIRE) #define GF_ATOMIC_BASE_ADD(_atomic, _value) \ __atomic_add_fetch(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_SUB(_atomic, _value) \ __atomic_sub_fetch(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_AND(_atomic, _value) \ __atomic_and_fetch(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_OR(_atomic, _value) \ __atomic_or_fetch(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_XOR(_atomic, _value) \ __atomic_xor_fetch(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_NAND(_atomic, _value) \ __atomic_nand_fetch(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_FETCH_ADD(_atomic, _value) \ __atomic_fetch_add(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_FETCH_SUB(_atomic, _value) \ __atomic_fetch_sub(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_FETCH_AND(_atomic, _value) \ __atomic_fetch_and(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_FETCH_OR(_atomic, _value) \ __atomic_fetch_or(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_FETCH_XOR(_atomic, _value) \ __atomic_fetch_xor(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_FETCH_NAND(_atomic, _value) \ __atomic_fetch_nand(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_SWAP(_atomic, _value) \ __atomic_exchange_n(&(_atomic).value, (_value), __ATOMIC_ACQ_REL) #define GF_ATOMIC_BASE_CMP_SWAP(_atomic, _expected, _value) \ ({ \ typeof((_atomic).value) __expected = (_expected); \ __atomic_compare_exchange_n(&(_atomic).value, &__expected, (_value), \ 0, __ATOMIC_ACQ_REL, __ATOMIC_ACQUIRE); \ }) #elif defined(HAVE_SYNC_BUILTINS) /* If compiler doesn't support __atomic builtins but supports __sync builtins, * we use them. */ #define GF_ATOMIC_BASE_INIT(_atomic, _value) \ do { \ (_atomic).value = (_value); \ __sync_synchronize(); \ } while (0) #define GF_ATOMIC_BASE_ADD(_atomic, _value) \ __sync_add_and_fetch(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_SUB(_atomic, _value) \ __sync_sub_and_fetch(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_AND(_atomic, _value) \ __sync_and_and_fetch(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_OR(_atomic, _value) \ __sync_or_and_fetch(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_XOR(_atomic, _value) \ __sync_xor_and_fetch(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_NAND(_atomic, _value) \ __sync_nand_and_fetch(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_FETCH_ADD(_atomic, _value) \ __sync_fetch_and_add(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_FETCH_SUB(_atomic, _value) \ __sync_fetch_and_sub(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_FETCH_AND(_atomic, _value) \ __sync_fetch_and_and(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_FETCH_OR(_atomic, _value) \ __sync_fetch_and_or(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_FETCH_XOR(_atomic, _value) \ __sync_fetch_and_xor(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_FETCH_NAND(_atomic, _value) \ __sync_fetch_and_nand(&(_atomic).value, (_value)) #define GF_ATOMIC_BASE_SWAP(_atomic, _value) \ ({ \ __sync_synchronize(); \ __sync_lock_test_and_set(&(_atomic).value, (_value)); \ }) #define GF_ATOMIC_BASE_CMP_SWAP(_atomic, _expected, _value) \ __sync_bool_compare_and_swap(&(_atomic).value, (_expected), (_value)) #define GF_ATOMIC_BASE_GET(_atomic) GF_ATOMIC_BASE_ADD(_atomic, 0) #else /* !HAVE_ATOMIC_BUILTINS && !HAVE_SYNC_BUILTINS */ /* The compiler doesn't support any atomic builtin. We fallback to the * mutex-based implementation. */ #define GF_ATOMIC_BASE_INIT(_atomic, _value) \ GF_ATOMIC_LOCK_INIT(_atomic, _value) #define GF_ATOMIC_BASE_GET(_atomic) GF_ATOMIC_LOCK_GET(_atomic) #define GF_ATOMIC_BASE_ADD(_atomic, _value) GF_ATOMIC_LOCK_ADD(_atomic, _value) #define GF_ATOMIC_BASE_SUB(_atomic, _value) GF_ATOMIC_LOCK_SUB(_atomic, _value) #define GF_ATOMIC_BASE_AND(_atomic, _value) GF_ATOMIC_LOCK_AND(_atomic, _value) #define GF_ATOMIC_BASE_OR(_atomic, _value) GF_ATOMIC_LOCK_OR(_atomic, _value) #define GF_ATOMIC_BASE_XOR(_atomic, _value) GF_ATOMIC_LOCK_XOR(_atomic, _value) #define GF_ATOMIC_BASE_NAND(_atomic, _value) \ GF_ATOMIC_LOCK_NAND(_atomic, _value) #define GF_ATOMIC_BASE_FETCH_ADD(_atomic, _value) \ GF_ATOMIC_LOCK_FETCH_ADD(_atomic, _value) #define GF_ATOMIC_BASE_FETCH_SUB(_atomic, _value) \ GF_ATOMIC_LOCK_FETCH_SUB(_atomic, _value) #define GF_ATOMIC_BASE_FETCH_AND(_atomic, _value) \ GF_ATOMIC_LOCK_FETCH_AND(_atomic, _value) #define GF_ATOMIC_BASE_FETCH_OR(_atomic, _value) \ GF_ATOMIC_LOCK_FETCH_OR(_atomic, _value) #define GF_ATOMIC_BASE_FETCH_XOR(_atomic, _value) \ GF_ATOMIC_LOCK_FETCH_XOR(_atomic, _value) #define GF_ATOMIC_BASE_FETCH_NAND(_atomic, _value) \ GF_ATOMIC_LOCK_FETCH_NAND(_atomic, _value) #define GF_ATOMIC_BASE_SWAP(_atomic, _value) \ GF_ATOMIC_LOCK_SWAP(_atomic, _value) #define GF_ATOMIC_BASE_CMP_SWAP(_atomic, _expected, _value) \ GF_ATOMIC_LOCK_CMP_SWAP(_atomic, _expected, _value) #endif /* HAVE_(ATOMIC|SYNC)_BUILTINS */ /* Here we declare the real atomic macros available to the user. */ /* All macros have a 'gf_atomic_xxx' as 1st argument */ #define GF_ATOMIC_INIT(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, INIT, _value) #define GF_ATOMIC_GET(_atomic) GF_ATOMIC_CHOOSE(_atomic, GET) #define GF_ATOMIC_ADD(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, ADD, _value) #define GF_ATOMIC_SUB(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, SUB, _value) #define GF_ATOMIC_AND(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, AND, _value) #define GF_ATOMIC_OR(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, OR, _value) #define GF_ATOMIC_XOR(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, XOR, _value) #define GF_ATOMIC_NAND(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, NAND, _value) #define GF_ATOMIC_FETCH_ADD(_atomic, _value) \ GF_ATOMIC_CHOOSE(_atomic, FETCH_ADD, _value) #define GF_ATOMIC_FETCH_SUB(_atomic, _value) \ GF_ATOMIC_CHOOSE(_atomic, FETCH_SUB, _value) #define GF_ATOMIC_FETCH_AND(_atomic, _value) \ GF_ATOMIC_CHOOSE(_atomic, FETCH_AND, _value) #define GF_ATOMIC_FETCH_OR(_atomic, _value) \ GF_ATOMIC_CHOOSE(_atomic, FETCH_OR, _value) #define GF_ATOMIC_FETCH_XOR(_atomic, _value) \ GF_ATOMIC_CHOOSE(_atomic, FETCH_XOR, _value) #define GF_ATOMIC_FETCH_NAND(_atomic, _value) \ GF_ATOMIC_CHOOSE(_atomic, FETCH_NAND, _value) #define GF_ATOMIC_SWAP(_atomic, _value) GF_ATOMIC_CHOOSE(_atomic, SWAP, _value) #define GF_ATOMIC_CMP_SWAP(_atomic, _expected, _value) \ GF_ATOMIC_CHOOSE(_atomic, CMP_SWAP, _expected, _value) #define GF_ATOMIC_INC(_atomic) GF_ATOMIC_ADD(_atomic, 1) #define GF_ATOMIC_DEC(_atomic) GF_ATOMIC_SUB(_atomic, 1) #define GF_ATOMIC_FETCH_INC(_atomic) GF_ATOMIC_FETCH_ADD(_atomic, 1) #define GF_ATOMIC_FETCH_DEC(_atomic) GF_ATOMIC_FETCH_SUB(_atomic, 1) #endif /* _ATOMIC_H */