/*
* Copyright (c) 2013-2019, Huawei Technologies Co., Ltd. All rights reserved.
* Copyright (c) 2020, Huawei Device Co., Ltd. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* @defgroup los_atomic Atomic
* @ingroup kernel
*/
#ifndef __LOS_ATOMIC_H__
#define __LOS_ATOMIC_H__
#include "los_typedef.h"
#ifdef __cplusplus
#if __cplusplus
extern "C" {
#endif /* __cplusplus */
#endif /* __cplusplus */
typedef volatile INT32 Atomic;
typedef volatile INT64 Atomic64;
/**
* @ingroup los_atomic
* @brief Atomic read.
*
* @par Description:
* This API is used to implement the atomic read and return the result value of the read.
* @attention
*
* - The pointer v must not be NULL.
*
*
* @param v [IN] The reading pointer.
*
* @retval #INT32 The result value of the read.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicRead(const Atomic *v)
{
return *(volatile INT32 *)v;
}
/**
* @ingroup los_atomic
* @brief Atomic setting.
*
* @par Description:
* This API is used to implement the atomic setting operation.
* @attention
*
* - The pointer v must not be NULL.
*
*
* @param v [IN] The variable pointer to be setting.
* @param setVal [IN] The value to be setting.
*
* @retval none.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE VOID LOS_AtomicSet(Atomic *v, INT32 setVal)
{
*(volatile INT32 *)v = setVal;
}
/**
* @ingroup los_atomic
* @brief Atomic addition.
*
* @par Description:
* This API is used to implement the atomic addition and return the result value of the augend.
* @attention
*
* - The pointer v must not be NULL.
* - If the addtion result is not in the range of representable values for 32-bit signed integer,
* an int integer overflow may occur to the return value
*
*
* @param v [IN] The augend pointer.
* @param addVal [IN] The addend.
*
* @retval #INT32 The result value of the augend.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicAdd(Atomic *v, INT32 addVal)
{
INT32 val;
UINT32 status;
do {
__asm__ __volatile__("ldrex %1, [%2]\n"
"add %1, %1, %3\n"
"strex %0, %1, [%2]"
: "=&r"(status), "=&r"(val)
: "r"(v), "r"(addVal)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic subtraction.
*
* @par Description:
* This API is used to implement the atomic subtraction and return the result value of the minuend.
* @attention
*
* - The pointer v must not be NULL.
* - If the subtraction result is not in the range of representable values for 32-bit signed integer,
* an int integer overflow may occur to the return value
*
*
* @param v [IN] The minuend pointer.
* @param subVal [IN] The subtrahend.
*
* @retval #INT32 The result value of the minuend.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicSub(Atomic *v, INT32 subVal)
{
INT32 val;
UINT32 status;
do {
__asm__ __volatile__("ldrex %1, [%2]\n"
"sub %1, %1, %3\n"
"strex %0, %1, [%2]"
: "=&r"(status), "=&r"(val)
: "r"(v), "r"(subVal)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic addSelf.
*
* @par Description:
* This API is used to implement the atomic addSelf.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT_MAX to avoid integer overflow after adding 1.
*
*
* @param v [IN] The addSelf variable pointer.
*
* @retval none.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE VOID LOS_AtomicInc(Atomic *v)
{
INT32 val;
UINT32 status;
do {
__asm__ __volatile__("ldrex %0, [%3]\n"
"add %0, %0, #1\n"
"strex %1, %0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
}
/**
* @ingroup los_atomic
* @brief Atomic addSelf.
*
* @par Description:
* This API is used to implement the atomic addSelf and return the result of addSelf.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT_MAX to avoid integer overflow after adding 1.
*
*
* @param v [IN] The addSelf variable pointer.
*
* @retval #INT32 The return value of variable addSelf.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicIncRet(Atomic *v)
{
INT32 val;
UINT32 status;
do {
__asm__ __volatile__("ldrex %0, [%3]\n"
"add %0, %0, #1\n"
"strex %1, %0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic auto-decrement.
*
* @par Description:
* This API is used to implementating the atomic auto-decrement.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT_MIN to avoid overflow after reducing 1.
*
*
* @param v [IN] The auto-decrement variable pointer.
*
* @retval none.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE VOID LOS_AtomicDec(Atomic *v)
{
INT32 val;
UINT32 status;
do {
__asm__ __volatile__("ldrex %0, [%3]\n"
"sub %0, %0, #1\n"
"strex %1, %0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
}
/**
* @ingroup los_atomic
* @brief Atomic auto-decrement.
*
* @par Description:
* This API is used to implementating the atomic auto-decrement and return the result of auto-decrement.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT_MIN to avoid overflow after reducing 1.
*
*
* @param v [IN] The auto-decrement variable pointer.
*
* @retval #INT32 The return value of variable auto-decrement.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicDecRet(Atomic *v)
{
INT32 val;
UINT32 status;
do {
__asm__ __volatile__("ldrex %0, [%3]\n"
"sub %0, %0, #1\n"
"strex %1, %0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic64 read.
*
* @par Description:
* This API is used to implement the atomic64 read and return the result value of the read.
* @attention
*
* - The pointer v must not be NULL.
*
*
* @param v [IN] The reading pointer.
*
* @retval #INT64 The result value of the read.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT64 LOS_Atomic64Read(const Atomic64 *v)
{
INT64 val;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%1]"
: "=&r"(val)
: "r"(v)
: "cc");
} while (0);
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic64 setting.
*
* @par Description:
* This API is used to implement the atomic64 setting operation.
* @attention
*
* - The pointer v must not be NULL.
*
*
* @param v [IN] The variable pointer to be setting.
* @param setVal [IN] The value to be setting.
*
* @retval none.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE VOID LOS_Atomic64Set(Atomic64 *v, INT64 setVal)
{
INT64 tmp;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %1, %H1, [%2]\n"
"strexd %0, %3, %H3, [%2]"
: "=&r"(status), "=&r"(tmp)
: "r"(v), "r"(setVal)
: "cc");
} while (__builtin_expect(status != 0, 0));
}
/**
* @ingroup los_atomic
* @brief Atomic64 addition.
*
* @par Description:
* This API is used to implement the atomic64 addition and return the result value of the augend.
* @attention
*
* - The pointer v must not be NULL.
* - If the addtion result is not in the range of representable values for 64-bit signed integer,
* an int integer overflow may occur to the return value
*
*
* @param v [IN] The augend pointer.
* @param addVal [IN] The addend.
*
* @retval #INT64 The result value of the augend.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT64 LOS_Atomic64Add(Atomic64 *v, INT64 addVal)
{
INT64 val;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %1, %H1, [%2]\n"
"adds %Q1, %Q1, %Q3\n"
"adc %R1, %R1, %R3\n"
"strexd %0, %1, %H1, [%2]"
: "=&r"(status), "=&r"(val)
: "r"(v), "r"(addVal)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic64 subtraction.
*
* @par Description:
* This API is used to implement the atomic64 subtraction and return the result value of the minuend.
* @attention
*
* - The pointer v must not be NULL.
* - If the subtraction result is not in the range of representable values for 64-bit signed integer,
* an int integer overflow may occur to the return value
*
*
* @param v [IN] The minuend pointer.
* @param subVal [IN] The subtrahend.
*
* @retval #INT64 The result value of the minuend.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT64 LOS_Atomic64Sub(Atomic64 *v, INT64 subVal)
{
INT64 val;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %1, %H1, [%2]\n"
"subs %Q1, %Q1, %Q3\n"
"sbc %R1, %R1, %R3\n"
"strexd %0, %1, %H1, [%2]"
: "=&r"(status), "=&r"(val)
: "r"(v), "r"(subVal)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic64 addSelf.
*
* @par Description:
* This API is used to implement the atomic64 addSelf .
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT64_MAX to avoid integer overflow after adding 1.
*
*
* @param v [IN] The addSelf variable pointer.
*
* @retval none.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE VOID LOS_Atomic64Inc(Atomic64 *v)
{
INT64 val;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%3]\n"
"adds %Q0, %Q0, #1\n"
"adc %R0, %R0, #0\n"
"strexd %1, %0, %H0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
}
/**
* @ingroup los_atomic
* @brief Atomic64 addSelf.
*
* @par Description:
* This API is used to implement the atomic64 addSelf and return the result of addSelf.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT64_MAX to avoid integer overflow after adding 1.
*
*
* @param v [IN] The addSelf variable pointer.
*
* @retval #INT64 The return value of variable addSelf.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT64 LOS_Atomic64IncRet(Atomic64 *v)
{
INT64 val;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%3]\n"
"adds %Q0, %Q0, #1\n"
"adc %R0, %R0, #0\n"
"strexd %1, %0, %H0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic64 auto-decrement.
*
* @par Description:
* This API is used to implementating the atomic64 auto-decrement.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT64_MIN to avoid overflow after reducing 1.
*
*
* @param v [IN] The auto-decrement variable pointer.
*
* @retval none.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE VOID LOS_Atomic64Dec(Atomic64 *v)
{
INT64 val;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%3]\n"
"subs %Q0, %Q0, #1\n"
"sbc %R0, %R0, #0\n"
"strexd %1, %0, %H0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
}
/**
* @ingroup los_atomic
* @brief Atomic64 auto-decrement.
*
* @par Description:
* This API is used to implementating the atomic64 auto-decrement and return the result of auto-decrement.
* @attention
*
* - The pointer v must not be NULL.
* - The value which v point to must not be INT64_MIN to avoid overflow after reducing 1.
*
*
* @param v [IN] The auto-decrement variable pointer.
*
* @retval #INT64 The return value of variable auto-decrement.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT64 LOS_Atomic64DecRet(Atomic64 *v)
{
INT64 val;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%3]\n"
"subs %Q0, %Q0, #1\n"
"sbc %R0, %R0, #0\n"
"strexd %1, %0, %H0, [%3]"
: "=&r"(val), "=&r"(status), "+m"(*v)
: "r"(v)
: "cc");
} while (__builtin_expect(status != 0, 0));
return val;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 8-bit variable.
*
* @par Description:
* This API is used to implement the atomic exchange for 8-bit variable and
* return the previous value of the atomic variable.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The exchange value.
*
* @retval #INT32 The previous value of the atomic variable
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicXchgByte(volatile INT8 *v, INT32 val)
{
INT32 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrexb %0, [%3]\n"
"strexb %1, %4, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 16-bit variable.
*
* @par Description:
* This API is used to implement the atomic exchange for 16-bit variable and
* return the previous value of the atomic variable.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The exchange value.
*
* @retval #INT32 The previous value of the atomic variable
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicXchg16bits(volatile INT16 *v, INT32 val)
{
INT32 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrexh %0, [%3]\n"
"strexh %1, %4, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 32-bit variable.
*
* @par Description:
* This API is used to implement the atomic exchange for 32-bit variable
* and return the previous value of the atomic variable.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The exchange value.
*
* @retval #INT32 The previous value of the atomic variable
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT32 LOS_AtomicXchg32bits(Atomic *v, INT32 val)
{
INT32 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrex %0, [%3]\n"
"strex %1, %4, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 64-bit variable.
*
* @par Description:
* This API is used to implement the atomic exchange for 64-bit variable
* and return the previous value of the atomic variable.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The exchange value.
*
* @retval #INT64 The previous value of the atomic variable
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE INT64 LOS_AtomicXchg64bits(Atomic64 *v, INT64 val)
{
INT64 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%3]\n"
"strexd %1, %4, %H4, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 8-bit variable with compare.
*
* @par Description:
* This API is used to implement the atomic exchange for 8-bit variable, if the value of variable is equal to oldVal.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The new value.
* @param oldVal [IN] The old value.
*
* @retval TRUE The previous value of the atomic variable is not equal to oldVal.
* @retval FALSE The previous value of the atomic variable is equal to oldVal.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE BOOL LOS_AtomicCmpXchgByte(volatile INT8 *v, INT32 val, INT32 oldVal)
{
INT32 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrexb %0, [%3]\n"
"mov %1, #0\n"
"teq %0, %4\n"
"strexbeq %1, %5, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(oldVal), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal != oldVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 16-bit variable with compare.
*
* @par Description:
* This API is used to implement the atomic exchange for 16-bit variable, if the value of variable is equal to oldVal.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The new value.
* @param oldVal [IN] The old value.
*
* @retval TRUE The previous value of the atomic variable is not equal to oldVal.
* @retval FALSE The previous value of the atomic variable is equal to oldVal.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE BOOL LOS_AtomicCmpXchg16bits(volatile INT16 *v, INT32 val, INT32 oldVal)
{
INT32 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrexh %0, [%3]\n"
"mov %1, #0\n"
"teq %0, %4\n"
"strexheq %1, %5, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(oldVal), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal != oldVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 32-bit variable with compare.
*
* @par Description:
* This API is used to implement the atomic exchange for 32-bit variable, if the value of variable is equal to oldVal.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The new value.
* @param oldVal [IN] The old value.
*
* @retval TRUE The previous value of the atomic variable is not equal to oldVal.
* @retval FALSE The previous value of the atomic variable is equal to oldVal.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE BOOL LOS_AtomicCmpXchg32bits(Atomic *v, INT32 val, INT32 oldVal)
{
INT32 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrex %0, [%3]\n"
"mov %1, #0\n"
"teq %0, %4\n"
"strexeq %1, %5, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(oldVal), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal != oldVal;
}
/**
* @ingroup los_atomic
* @brief Atomic exchange for 64-bit variable with compare.
*
* @par Description:
* This API is used to implement the atomic exchange for 64-bit variable, if the value of variable is equal to oldVal.
* @attention
* The pointer v must not be NULL.
*
* @param v [IN] The variable pointer.
* @param val [IN] The new value.
* @param oldVal [IN] The old value.
*
* @retval TRUE The previous value of the atomic variable is not equal to oldVal.
* @retval FALSE The previous value of the atomic variable is equal to oldVal.
* @par Dependency:
* - los_atomic.h: the header file that contains the API declaration.
* @see
*/
STATIC INLINE BOOL LOS_AtomicCmpXchg64bits(Atomic64 *v, INT64 val, INT64 oldVal)
{
INT64 prevVal;
UINT32 status;
do {
__asm__ __volatile__("ldrexd %0, %H0, [%3]\n"
"mov %1, #0\n"
"teq %0, %4\n"
"teqeq %H0, %H4\n"
"strexdeq %1, %5, %H5, [%3]"
: "=&r"(prevVal), "=&r"(status), "+m"(*v)
: "r"(v), "r"(oldVal), "r"(val)
: "cc");
} while (__builtin_expect(status != 0, 0));
return prevVal != oldVal;
}
#ifdef __cplusplus
#if __cplusplus
}
#endif /* __cplusplus */
#endif /* __cplusplus */
#endif /* __LOS_ATOMIC_H__ */