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Diffstat (limited to 'libglusterfs/src/glusterfs/atomic.h')
| -rw-r--r-- | libglusterfs/src/glusterfs/atomic.h | 459 |
1 files changed, 459 insertions, 0 deletions
diff --git a/libglusterfs/src/glusterfs/atomic.h b/libglusterfs/src/glusterfs/atomic.h new file mode 100644 index 00000000000..ced81748218 --- /dev/null +++ b/libglusterfs/src/glusterfs/atomic.h @@ -0,0 +1,459 @@ +/* + Copyright (c) 2017 Red Hat, Inc. <http://www.redhat.com> + 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 <inttypes.h> +#include <stdbool.h> + +#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 */ |