f-stack/dpdk/lib/librte_eal/include/generic/rte_atomic.h

1117 lines
24 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2014 Intel Corporation
*/
#ifndef _RTE_ATOMIC_H_
#define _RTE_ATOMIC_H_
/**
* @file
* Atomic Operations
*
* This file defines a generic API for atomic operations.
*/
#include <stdint.h>
#include <rte_common.h>
#ifdef __DOXYGEN__
/** @name Memory Barrier
*/
///@{
/**
* General memory barrier.
*
* Guarantees that the LOAD and STORE operations generated before the
* barrier occur before the LOAD and STORE operations generated after.
*/
static inline void rte_mb(void);
/**
* Write memory barrier.
*
* Guarantees that the STORE operations generated before the barrier
* occur before the STORE operations generated after.
*/
static inline void rte_wmb(void);
/**
* Read memory barrier.
*
* Guarantees that the LOAD operations generated before the barrier
* occur before the LOAD operations generated after.
*/
static inline void rte_rmb(void);
///@}
/** @name SMP Memory Barrier
*/
///@{
/**
* General memory barrier between lcores
*
* Guarantees that the LOAD and STORE operations that precede the
* rte_smp_mb() call are globally visible across the lcores
* before the LOAD and STORE operations that follows it.
*/
static inline void rte_smp_mb(void);
/**
* Write memory barrier between lcores
*
* Guarantees that the STORE operations that precede the
* rte_smp_wmb() call are globally visible across the lcores
* before the STORE operations that follows it.
*/
static inline void rte_smp_wmb(void);
/**
* Read memory barrier between lcores
*
* Guarantees that the LOAD operations that precede the
* rte_smp_rmb() call are globally visible across the lcores
* before the LOAD operations that follows it.
*/
static inline void rte_smp_rmb(void);
///@}
/** @name I/O Memory Barrier
*/
///@{
/**
* General memory barrier for I/O device
*
* Guarantees that the LOAD and STORE operations that precede the
* rte_io_mb() call are visible to I/O device or CPU before the
* LOAD and STORE operations that follow it.
*/
static inline void rte_io_mb(void);
/**
* Write memory barrier for I/O device
*
* Guarantees that the STORE operations that precede the
* rte_io_wmb() call are visible to I/O device before the STORE
* operations that follow it.
*/
static inline void rte_io_wmb(void);
/**
* Read memory barrier for IO device
*
* Guarantees that the LOAD operations on I/O device that precede the
* rte_io_rmb() call are visible to CPU before the LOAD
* operations that follow it.
*/
static inline void rte_io_rmb(void);
///@}
#endif /* __DOXYGEN__ */
/**
* Compiler barrier.
*
* Guarantees that operation reordering does not occur at compile time
* for operations directly before and after the barrier.
*/
#define rte_compiler_barrier() do { \
asm volatile ("" : : : "memory"); \
} while(0)
/**
* Synchronization fence between threads based on the specified memory order.
*/
static inline void rte_atomic_thread_fence(int memorder);
/*------------------------- 16 bit atomic operations -------------------------*/
/**
* Atomic compare and set.
*
* (atomic) equivalent to:
* if (*dst == exp)
* *dst = src (all 16-bit words)
*
* @param dst
* The destination location into which the value will be written.
* @param exp
* The expected value.
* @param src
* The new value.
* @return
* Non-zero on success; 0 on failure.
*/
static inline int
rte_atomic16_cmpset(volatile uint16_t *dst, uint16_t exp, uint16_t src);
#ifdef RTE_FORCE_INTRINSICS
static inline int
rte_atomic16_cmpset(volatile uint16_t *dst, uint16_t exp, uint16_t src)
{
return __sync_bool_compare_and_swap(dst, exp, src);
}
#endif
/**
* Atomic exchange.
*
* (atomic) equivalent to:
* ret = *dst
* *dst = val;
* return ret;
*
* @param dst
* The destination location into which the value will be written.
* @param val
* The new value.
* @return
* The original value at that location
*/
static inline uint16_t
rte_atomic16_exchange(volatile uint16_t *dst, uint16_t val);
#ifdef RTE_FORCE_INTRINSICS
static inline uint16_t
rte_atomic16_exchange(volatile uint16_t *dst, uint16_t val)
{
#if defined(__clang__)
return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
#else
return __atomic_exchange_2(dst, val, __ATOMIC_SEQ_CST);
#endif
}
#endif
/**
* The atomic counter structure.
*/
typedef struct {
volatile int16_t cnt; /**< An internal counter value. */
} rte_atomic16_t;
/**
* Static initializer for an atomic counter.
*/
#define RTE_ATOMIC16_INIT(val) { (val) }
/**
* Initialize an atomic counter.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic16_init(rte_atomic16_t *v)
{
v->cnt = 0;
}
/**
* Atomically read a 16-bit value from a counter.
*
* @param v
* A pointer to the atomic counter.
* @return
* The value of the counter.
*/
static inline int16_t
rte_atomic16_read(const rte_atomic16_t *v)
{
return v->cnt;
}
/**
* Atomically set a counter to a 16-bit value.
*
* @param v
* A pointer to the atomic counter.
* @param new_value
* The new value for the counter.
*/
static inline void
rte_atomic16_set(rte_atomic16_t *v, int16_t new_value)
{
v->cnt = new_value;
}
/**
* Atomically add a 16-bit value to an atomic counter.
*
* @param v
* A pointer to the atomic counter.
* @param inc
* The value to be added to the counter.
*/
static inline void
rte_atomic16_add(rte_atomic16_t *v, int16_t inc)
{
__sync_fetch_and_add(&v->cnt, inc);
}
/**
* Atomically subtract a 16-bit value from an atomic counter.
*
* @param v
* A pointer to the atomic counter.
* @param dec
* The value to be subtracted from the counter.
*/
static inline void
rte_atomic16_sub(rte_atomic16_t *v, int16_t dec)
{
__sync_fetch_and_sub(&v->cnt, dec);
}
/**
* Atomically increment a counter by one.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic16_inc(rte_atomic16_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic16_inc(rte_atomic16_t *v)
{
rte_atomic16_add(v, 1);
}
#endif
/**
* Atomically decrement a counter by one.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic16_dec(rte_atomic16_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic16_dec(rte_atomic16_t *v)
{
rte_atomic16_sub(v, 1);
}
#endif
/**
* Atomically add a 16-bit value to a counter and return the result.
*
* Atomically adds the 16-bits value (inc) to the atomic counter (v) and
* returns the value of v after addition.
*
* @param v
* A pointer to the atomic counter.
* @param inc
* The value to be added to the counter.
* @return
* The value of v after the addition.
*/
static inline int16_t
rte_atomic16_add_return(rte_atomic16_t *v, int16_t inc)
{
return __sync_add_and_fetch(&v->cnt, inc);
}
/**
* Atomically subtract a 16-bit value from a counter and return
* the result.
*
* Atomically subtracts the 16-bit value (inc) from the atomic counter
* (v) and returns the value of v after the subtraction.
*
* @param v
* A pointer to the atomic counter.
* @param dec
* The value to be subtracted from the counter.
* @return
* The value of v after the subtraction.
*/
static inline int16_t
rte_atomic16_sub_return(rte_atomic16_t *v, int16_t dec)
{
return __sync_sub_and_fetch(&v->cnt, dec);
}
/**
* Atomically increment a 16-bit counter by one and test.
*
* Atomically increments the atomic counter (v) by one and returns true if
* the result is 0, or false in all other cases.
*
* @param v
* A pointer to the atomic counter.
* @return
* True if the result after the increment operation is 0; false otherwise.
*/
static inline int rte_atomic16_inc_and_test(rte_atomic16_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic16_inc_and_test(rte_atomic16_t *v)
{
return __sync_add_and_fetch(&v->cnt, 1) == 0;
}
#endif
/**
* Atomically decrement a 16-bit counter by one and test.
*
* Atomically decrements the atomic counter (v) by one and returns true if
* the result is 0, or false in all other cases.
*
* @param v
* A pointer to the atomic counter.
* @return
* True if the result after the decrement operation is 0; false otherwise.
*/
static inline int rte_atomic16_dec_and_test(rte_atomic16_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic16_dec_and_test(rte_atomic16_t *v)
{
return __sync_sub_and_fetch(&v->cnt, 1) == 0;
}
#endif
/**
* Atomically test and set a 16-bit atomic counter.
*
* If the counter value is already set, return 0 (failed). Otherwise, set
* the counter value to 1 and return 1 (success).
*
* @param v
* A pointer to the atomic counter.
* @return
* 0 if failed; else 1, success.
*/
static inline int rte_atomic16_test_and_set(rte_atomic16_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic16_test_and_set(rte_atomic16_t *v)
{
return rte_atomic16_cmpset((volatile uint16_t *)&v->cnt, 0, 1);
}
#endif
/**
* Atomically set a 16-bit counter to 0.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void rte_atomic16_clear(rte_atomic16_t *v)
{
v->cnt = 0;
}
/*------------------------- 32 bit atomic operations -------------------------*/
/**
* Atomic compare and set.
*
* (atomic) equivalent to:
* if (*dst == exp)
* *dst = src (all 32-bit words)
*
* @param dst
* The destination location into which the value will be written.
* @param exp
* The expected value.
* @param src
* The new value.
* @return
* Non-zero on success; 0 on failure.
*/
static inline int
rte_atomic32_cmpset(volatile uint32_t *dst, uint32_t exp, uint32_t src);
#ifdef RTE_FORCE_INTRINSICS
static inline int
rte_atomic32_cmpset(volatile uint32_t *dst, uint32_t exp, uint32_t src)
{
return __sync_bool_compare_and_swap(dst, exp, src);
}
#endif
/**
* Atomic exchange.
*
* (atomic) equivalent to:
* ret = *dst
* *dst = val;
* return ret;
*
* @param dst
* The destination location into which the value will be written.
* @param val
* The new value.
* @return
* The original value at that location
*/
static inline uint32_t
rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val);
#ifdef RTE_FORCE_INTRINSICS
static inline uint32_t
rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val)
{
#if defined(__clang__)
return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
#else
return __atomic_exchange_4(dst, val, __ATOMIC_SEQ_CST);
#endif
}
#endif
/**
* The atomic counter structure.
*/
typedef struct {
volatile int32_t cnt; /**< An internal counter value. */
} rte_atomic32_t;
/**
* Static initializer for an atomic counter.
*/
#define RTE_ATOMIC32_INIT(val) { (val) }
/**
* Initialize an atomic counter.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic32_init(rte_atomic32_t *v)
{
v->cnt = 0;
}
/**
* Atomically read a 32-bit value from a counter.
*
* @param v
* A pointer to the atomic counter.
* @return
* The value of the counter.
*/
static inline int32_t
rte_atomic32_read(const rte_atomic32_t *v)
{
return v->cnt;
}
/**
* Atomically set a counter to a 32-bit value.
*
* @param v
* A pointer to the atomic counter.
* @param new_value
* The new value for the counter.
*/
static inline void
rte_atomic32_set(rte_atomic32_t *v, int32_t new_value)
{
v->cnt = new_value;
}
/**
* Atomically add a 32-bit value to an atomic counter.
*
* @param v
* A pointer to the atomic counter.
* @param inc
* The value to be added to the counter.
*/
static inline void
rte_atomic32_add(rte_atomic32_t *v, int32_t inc)
{
__sync_fetch_and_add(&v->cnt, inc);
}
/**
* Atomically subtract a 32-bit value from an atomic counter.
*
* @param v
* A pointer to the atomic counter.
* @param dec
* The value to be subtracted from the counter.
*/
static inline void
rte_atomic32_sub(rte_atomic32_t *v, int32_t dec)
{
__sync_fetch_and_sub(&v->cnt, dec);
}
/**
* Atomically increment a counter by one.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic32_inc(rte_atomic32_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic32_inc(rte_atomic32_t *v)
{
rte_atomic32_add(v, 1);
}
#endif
/**
* Atomically decrement a counter by one.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic32_dec(rte_atomic32_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic32_dec(rte_atomic32_t *v)
{
rte_atomic32_sub(v,1);
}
#endif
/**
* Atomically add a 32-bit value to a counter and return the result.
*
* Atomically adds the 32-bits value (inc) to the atomic counter (v) and
* returns the value of v after addition.
*
* @param v
* A pointer to the atomic counter.
* @param inc
* The value to be added to the counter.
* @return
* The value of v after the addition.
*/
static inline int32_t
rte_atomic32_add_return(rte_atomic32_t *v, int32_t inc)
{
return __sync_add_and_fetch(&v->cnt, inc);
}
/**
* Atomically subtract a 32-bit value from a counter and return
* the result.
*
* Atomically subtracts the 32-bit value (inc) from the atomic counter
* (v) and returns the value of v after the subtraction.
*
* @param v
* A pointer to the atomic counter.
* @param dec
* The value to be subtracted from the counter.
* @return
* The value of v after the subtraction.
*/
static inline int32_t
rte_atomic32_sub_return(rte_atomic32_t *v, int32_t dec)
{
return __sync_sub_and_fetch(&v->cnt, dec);
}
/**
* Atomically increment a 32-bit counter by one and test.
*
* Atomically increments the atomic counter (v) by one and returns true if
* the result is 0, or false in all other cases.
*
* @param v
* A pointer to the atomic counter.
* @return
* True if the result after the increment operation is 0; false otherwise.
*/
static inline int rte_atomic32_inc_and_test(rte_atomic32_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic32_inc_and_test(rte_atomic32_t *v)
{
return __sync_add_and_fetch(&v->cnt, 1) == 0;
}
#endif
/**
* Atomically decrement a 32-bit counter by one and test.
*
* Atomically decrements the atomic counter (v) by one and returns true if
* the result is 0, or false in all other cases.
*
* @param v
* A pointer to the atomic counter.
* @return
* True if the result after the decrement operation is 0; false otherwise.
*/
static inline int rte_atomic32_dec_and_test(rte_atomic32_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic32_dec_and_test(rte_atomic32_t *v)
{
return __sync_sub_and_fetch(&v->cnt, 1) == 0;
}
#endif
/**
* Atomically test and set a 32-bit atomic counter.
*
* If the counter value is already set, return 0 (failed). Otherwise, set
* the counter value to 1 and return 1 (success).
*
* @param v
* A pointer to the atomic counter.
* @return
* 0 if failed; else 1, success.
*/
static inline int rte_atomic32_test_and_set(rte_atomic32_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic32_test_and_set(rte_atomic32_t *v)
{
return rte_atomic32_cmpset((volatile uint32_t *)&v->cnt, 0, 1);
}
#endif
/**
* Atomically set a 32-bit counter to 0.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void rte_atomic32_clear(rte_atomic32_t *v)
{
v->cnt = 0;
}
/*------------------------- 64 bit atomic operations -------------------------*/
/**
* An atomic compare and set function used by the mutex functions.
* (atomic) equivalent to:
* if (*dst == exp)
* *dst = src (all 64-bit words)
*
* @param dst
* The destination into which the value will be written.
* @param exp
* The expected value.
* @param src
* The new value.
* @return
* Non-zero on success; 0 on failure.
*/
static inline int
rte_atomic64_cmpset(volatile uint64_t *dst, uint64_t exp, uint64_t src);
#ifdef RTE_FORCE_INTRINSICS
static inline int
rte_atomic64_cmpset(volatile uint64_t *dst, uint64_t exp, uint64_t src)
{
return __sync_bool_compare_and_swap(dst, exp, src);
}
#endif
/**
* Atomic exchange.
*
* (atomic) equivalent to:
* ret = *dst
* *dst = val;
* return ret;
*
* @param dst
* The destination location into which the value will be written.
* @param val
* The new value.
* @return
* The original value at that location
*/
static inline uint64_t
rte_atomic64_exchange(volatile uint64_t *dst, uint64_t val);
#ifdef RTE_FORCE_INTRINSICS
static inline uint64_t
rte_atomic64_exchange(volatile uint64_t *dst, uint64_t val)
{
#if defined(__clang__)
return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
#else
return __atomic_exchange_8(dst, val, __ATOMIC_SEQ_CST);
#endif
}
#endif
/**
* The atomic counter structure.
*/
typedef struct {
volatile int64_t cnt; /**< Internal counter value. */
} rte_atomic64_t;
/**
* Static initializer for an atomic counter.
*/
#define RTE_ATOMIC64_INIT(val) { (val) }
/**
* Initialize the atomic counter.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic64_init(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic64_init(rte_atomic64_t *v)
{
#ifdef __LP64__
v->cnt = 0;
#else
int success = 0;
uint64_t tmp;
while (success == 0) {
tmp = v->cnt;
success = rte_atomic64_cmpset((volatile uint64_t *)&v->cnt,
tmp, 0);
}
#endif
}
#endif
/**
* Atomically read a 64-bit counter.
*
* @param v
* A pointer to the atomic counter.
* @return
* The value of the counter.
*/
static inline int64_t
rte_atomic64_read(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int64_t
rte_atomic64_read(rte_atomic64_t *v)
{
#ifdef __LP64__
return v->cnt;
#else
int success = 0;
uint64_t tmp;
while (success == 0) {
tmp = v->cnt;
/* replace the value by itself */
success = rte_atomic64_cmpset((volatile uint64_t *)&v->cnt,
tmp, tmp);
}
return tmp;
#endif
}
#endif
/**
* Atomically set a 64-bit counter.
*
* @param v
* A pointer to the atomic counter.
* @param new_value
* The new value of the counter.
*/
static inline void
rte_atomic64_set(rte_atomic64_t *v, int64_t new_value);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic64_set(rte_atomic64_t *v, int64_t new_value)
{
#ifdef __LP64__
v->cnt = new_value;
#else
int success = 0;
uint64_t tmp;
while (success == 0) {
tmp = v->cnt;
success = rte_atomic64_cmpset((volatile uint64_t *)&v->cnt,
tmp, new_value);
}
#endif
}
#endif
/**
* Atomically add a 64-bit value to a counter.
*
* @param v
* A pointer to the atomic counter.
* @param inc
* The value to be added to the counter.
*/
static inline void
rte_atomic64_add(rte_atomic64_t *v, int64_t inc);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic64_add(rte_atomic64_t *v, int64_t inc)
{
__sync_fetch_and_add(&v->cnt, inc);
}
#endif
/**
* Atomically subtract a 64-bit value from a counter.
*
* @param v
* A pointer to the atomic counter.
* @param dec
* The value to be subtracted from the counter.
*/
static inline void
rte_atomic64_sub(rte_atomic64_t *v, int64_t dec);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic64_sub(rte_atomic64_t *v, int64_t dec)
{
__sync_fetch_and_sub(&v->cnt, dec);
}
#endif
/**
* Atomically increment a 64-bit counter by one and test.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic64_inc(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic64_inc(rte_atomic64_t *v)
{
rte_atomic64_add(v, 1);
}
#endif
/**
* Atomically decrement a 64-bit counter by one and test.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void
rte_atomic64_dec(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void
rte_atomic64_dec(rte_atomic64_t *v)
{
rte_atomic64_sub(v, 1);
}
#endif
/**
* Add a 64-bit value to an atomic counter and return the result.
*
* Atomically adds the 64-bit value (inc) to the atomic counter (v) and
* returns the value of v after the addition.
*
* @param v
* A pointer to the atomic counter.
* @param inc
* The value to be added to the counter.
* @return
* The value of v after the addition.
*/
static inline int64_t
rte_atomic64_add_return(rte_atomic64_t *v, int64_t inc);
#ifdef RTE_FORCE_INTRINSICS
static inline int64_t
rte_atomic64_add_return(rte_atomic64_t *v, int64_t inc)
{
return __sync_add_and_fetch(&v->cnt, inc);
}
#endif
/**
* Subtract a 64-bit value from an atomic counter and return the result.
*
* Atomically subtracts the 64-bit value (dec) from the atomic counter (v)
* and returns the value of v after the subtraction.
*
* @param v
* A pointer to the atomic counter.
* @param dec
* The value to be subtracted from the counter.
* @return
* The value of v after the subtraction.
*/
static inline int64_t
rte_atomic64_sub_return(rte_atomic64_t *v, int64_t dec);
#ifdef RTE_FORCE_INTRINSICS
static inline int64_t
rte_atomic64_sub_return(rte_atomic64_t *v, int64_t dec)
{
return __sync_sub_and_fetch(&v->cnt, dec);
}
#endif
/**
* Atomically increment a 64-bit counter by one and test.
*
* Atomically increments the atomic counter (v) by one and returns
* true if the result is 0, or false in all other cases.
*
* @param v
* A pointer to the atomic counter.
* @return
* True if the result after the addition is 0; false otherwise.
*/
static inline int rte_atomic64_inc_and_test(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic64_inc_and_test(rte_atomic64_t *v)
{
return rte_atomic64_add_return(v, 1) == 0;
}
#endif
/**
* Atomically decrement a 64-bit counter by one and test.
*
* Atomically decrements the atomic counter (v) by one and returns true if
* the result is 0, or false in all other cases.
*
* @param v
* A pointer to the atomic counter.
* @return
* True if the result after subtraction is 0; false otherwise.
*/
static inline int rte_atomic64_dec_and_test(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic64_dec_and_test(rte_atomic64_t *v)
{
return rte_atomic64_sub_return(v, 1) == 0;
}
#endif
/**
* Atomically test and set a 64-bit atomic counter.
*
* If the counter value is already set, return 0 (failed). Otherwise, set
* the counter value to 1 and return 1 (success).
*
* @param v
* A pointer to the atomic counter.
* @return
* 0 if failed; else 1, success.
*/
static inline int rte_atomic64_test_and_set(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline int rte_atomic64_test_and_set(rte_atomic64_t *v)
{
return rte_atomic64_cmpset((volatile uint64_t *)&v->cnt, 0, 1);
}
#endif
/**
* Atomically set a 64-bit counter to 0.
*
* @param v
* A pointer to the atomic counter.
*/
static inline void rte_atomic64_clear(rte_atomic64_t *v);
#ifdef RTE_FORCE_INTRINSICS
static inline void rte_atomic64_clear(rte_atomic64_t *v)
{
rte_atomic64_set(v, 0);
}
#endif
/*------------------------ 128 bit atomic operations -------------------------*/
/**
* 128-bit integer structure.
*/
RTE_STD_C11
typedef struct {
RTE_STD_C11
union {
uint64_t val[2];
#ifdef RTE_ARCH_64
__extension__ __int128 int128;
#endif
};
} __rte_aligned(16) rte_int128_t;
#ifdef __DOXYGEN__
/**
* An atomic compare and set function used by the mutex functions.
* (Atomically) Equivalent to:
* @code
* if (*dst == *exp)
* *dst = *src
* else
* *exp = *dst
* @endcode
*
* @note This function is currently available for the x86-64 and aarch64
* platforms.
*
* @note The success and failure arguments must be one of the __ATOMIC_* values
* defined in the C++11 standard. For details on their behavior, refer to the
* standard.
*
* @param dst
* The destination into which the value will be written.
* @param exp
* Pointer to the expected value. If the operation fails, this memory is
* updated with the actual value.
* @param src
* Pointer to the new value.
* @param weak
* A value of true allows the comparison to spuriously fail and allows the
* 'exp' update to occur non-atomically (i.e. a torn read may occur).
* Implementations may ignore this argument and only implement the strong
* variant.
* @param success
* If successful, the operation's memory behavior conforms to this (or a
* stronger) model.
* @param failure
* If unsuccessful, the operation's memory behavior conforms to this (or a
* stronger) model. This argument cannot be __ATOMIC_RELEASE,
* __ATOMIC_ACQ_REL, or a stronger model than success.
* @return
* Non-zero on success; 0 on failure.
*/
__rte_experimental
static inline int
rte_atomic128_cmp_exchange(rte_int128_t *dst,
rte_int128_t *exp,
const rte_int128_t *src,
unsigned int weak,
int success,
int failure);
#endif /* __DOXYGEN__ */
#endif /* _RTE_ATOMIC_H_ */