Nie możesz wybrać więcej, niż 25 tematów
Tematy muszą się zaczynać od litery lub cyfry, mogą zawierać myślniki ('-') i mogą mieć do 35 znaków.
251 wiersze
7.3 KiB
251 wiersze
7.3 KiB
#ifndef __LIBS_ATOMIC_H__
|
|
#define __LIBS_ATOMIC_H__
|
|
|
|
/* Atomic operations that C can't guarantee us. Useful for resource counting etc.. */
|
|
|
|
typedef struct {
|
|
volatile int counter;
|
|
} atomic_t;
|
|
|
|
static inline int atomic_read(const atomic_t *v) __attribute__((always_inline));
|
|
static inline void atomic_set(atomic_t *v, int i) __attribute__((always_inline));
|
|
static inline void atomic_add(atomic_t *v, int i) __attribute__((always_inline));
|
|
static inline void atomic_sub(atomic_t *v, int i) __attribute__((always_inline));
|
|
static inline bool atomic_sub_test_zero(atomic_t *v, int i) __attribute__((always_inline));
|
|
static inline void atomic_inc(atomic_t *v) __attribute__((always_inline));
|
|
static inline void atomic_dec(atomic_t *v) __attribute__((always_inline));
|
|
static inline bool atomic_inc_test_zero(atomic_t *v) __attribute__((always_inline));
|
|
static inline bool atomic_dec_test_zero(atomic_t *v) __attribute__((always_inline));
|
|
static inline int atomic_add_return(atomic_t *v, int i) __attribute__((always_inline));
|
|
static inline int atomic_sub_return(atomic_t *v, int i) __attribute__((always_inline));
|
|
|
|
/* *
|
|
* atomic_read - read atomic variable
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically reads the value of @v.
|
|
* */
|
|
static inline int
|
|
atomic_read(const atomic_t *v) {
|
|
return v->counter;
|
|
}
|
|
|
|
/* *
|
|
* atomic_set - set atomic variable
|
|
* @v: pointer of type atomic_t
|
|
* @i: required value
|
|
*
|
|
* Atomically sets the value of @v to @i.
|
|
* */
|
|
static inline void
|
|
atomic_set(atomic_t *v, int i) {
|
|
v->counter = i;
|
|
}
|
|
|
|
/* *
|
|
* atomic_add - add integer to atomic variable
|
|
* @v: pointer of type atomic_t
|
|
* @i: integer value to add
|
|
*
|
|
* Atomically adds @i to @v.
|
|
* */
|
|
static inline void
|
|
atomic_add(atomic_t *v, int i) {
|
|
asm volatile ("addl %1, %0" : "+m" (v->counter) : "ir" (i));
|
|
}
|
|
|
|
/* *
|
|
* atomic_sub - subtract integer from atomic variable
|
|
* @v: pointer of type atomic_t
|
|
* @i: integer value to subtract
|
|
*
|
|
* Atomically subtracts @i from @v.
|
|
* */
|
|
static inline void
|
|
atomic_sub(atomic_t *v, int i) {
|
|
asm volatile("subl %1, %0" : "+m" (v->counter) : "ir" (i));
|
|
}
|
|
|
|
/* *
|
|
* atomic_sub_test_zero - subtract value from variable and test result
|
|
* @v: pointer of type atomic_t
|
|
* @i: integer value to subtract
|
|
*
|
|
* Atomically subtracts @i from @v and
|
|
* returns true if the result is zero, or false for all other cases.
|
|
* */
|
|
static inline bool
|
|
atomic_sub_test_zero(atomic_t *v, int i) {
|
|
unsigned char c;
|
|
asm volatile("subl %2, %0; sete %1" : "+m" (v->counter), "=qm" (c) : "ir" (i) : "memory");
|
|
return c != 0;
|
|
}
|
|
|
|
/* *
|
|
* atomic_inc - increment atomic variable
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically increments @v by 1.
|
|
* */
|
|
static inline void
|
|
atomic_inc(atomic_t *v) {
|
|
asm volatile("incl %0" : "+m" (v->counter));
|
|
}
|
|
|
|
/* *
|
|
* atomic_dec - decrement atomic variable
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically decrements @v by 1.
|
|
* */
|
|
static inline void
|
|
atomic_dec(atomic_t *v) {
|
|
asm volatile("decl %0" : "+m" (v->counter));
|
|
}
|
|
|
|
/* *
|
|
* atomic_inc_test_zero - increment and test
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically increments @v by 1 and
|
|
* returns true if the result is zero, or false for all other cases.
|
|
* */
|
|
static inline bool
|
|
atomic_inc_test_zero(atomic_t *v) {
|
|
unsigned char c;
|
|
asm volatile("incl %0; sete %1" : "+m" (v->counter), "=qm" (c) :: "memory");
|
|
return c != 0;
|
|
}
|
|
|
|
/* *
|
|
* atomic_dec_test_zero - decrement and test
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically decrements @v by 1 and
|
|
* returns true if the result is 0, or false for all other cases.
|
|
* */
|
|
static inline bool
|
|
atomic_dec_test_zero(atomic_t *v) {
|
|
unsigned char c;
|
|
asm volatile("decl %0; sete %1" : "+m" (v->counter), "=qm" (c) :: "memory");
|
|
return c != 0;
|
|
}
|
|
|
|
/* *
|
|
* atomic_add_return - add integer and return
|
|
* @i: integer value to add
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically adds @i to @v and returns @i + @v
|
|
* Requires Modern 486+ processor
|
|
* */
|
|
static inline int
|
|
atomic_add_return(atomic_t *v, int i) {
|
|
int __i = i;
|
|
asm volatile("xaddl %0, %1" : "+r" (i), "+m" (v->counter) :: "memory");
|
|
return i + __i;
|
|
}
|
|
|
|
/* *
|
|
* atomic_sub_return - subtract integer and return
|
|
* @v: pointer of type atomic_t
|
|
* @i: integer value to subtract
|
|
*
|
|
* Atomically subtracts @i from @v and returns @v - @i
|
|
* */
|
|
static inline int
|
|
atomic_sub_return(atomic_t *v, int i) {
|
|
return atomic_add_return(v, -i);
|
|
}
|
|
|
|
static inline void set_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
static inline void clear_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
static inline void change_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
static inline bool test_and_set_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
static inline bool test_and_clear_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
static inline bool test_and_change_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
static inline bool test_bit(int nr, volatile void *addr) __attribute__((always_inline));
|
|
|
|
/* *
|
|
* set_bit - Atomically set a bit in memory
|
|
* @nr: the bit to set
|
|
* @addr: the address to start counting from
|
|
*
|
|
* Note that @nr may be almost arbitrarily large; this function is not
|
|
* restricted to acting on a single-word quantity.
|
|
* */
|
|
static inline void
|
|
set_bit(int nr, volatile void *addr) {
|
|
asm volatile ("btsl %1, %0" :"=m" (*(volatile long *)addr) : "Ir" (nr));
|
|
}
|
|
|
|
/* *
|
|
* clear_bit - Atomically clears a bit in memory
|
|
* @nr: the bit to clear
|
|
* @addr: the address to start counting from
|
|
* */
|
|
static inline void
|
|
clear_bit(int nr, volatile void *addr) {
|
|
asm volatile ("btrl %1, %0" :"=m" (*(volatile long *)addr) : "Ir" (nr));
|
|
}
|
|
|
|
/* *
|
|
* change_bit - Atomically toggle a bit in memory
|
|
* @nr: the bit to change
|
|
* @addr: the address to start counting from
|
|
* */
|
|
static inline void
|
|
change_bit(int nr, volatile void *addr) {
|
|
asm volatile ("btcl %1, %0" :"=m" (*(volatile long *)addr) : "Ir" (nr));
|
|
}
|
|
|
|
/* *
|
|
* test_and_set_bit - Atomically set a bit and return its old value
|
|
* @nr: the bit to set
|
|
* @addr: the address to count from
|
|
* */
|
|
static inline bool
|
|
test_and_set_bit(int nr, volatile void *addr) {
|
|
int oldbit;
|
|
asm volatile ("btsl %2, %1; sbbl %0, %0" : "=r" (oldbit), "=m" (*(volatile long *)addr) : "Ir" (nr) : "memory");
|
|
return oldbit != 0;
|
|
}
|
|
|
|
/* *
|
|
* test_and_clear_bit - Atomically clear a bit and return its old value
|
|
* @nr: the bit to clear
|
|
* @addr: the address to count from
|
|
* */
|
|
static inline bool
|
|
test_and_clear_bit(int nr, volatile void *addr) {
|
|
int oldbit;
|
|
asm volatile ("btrl %2, %1; sbbl %0, %0" : "=r" (oldbit), "=m" (*(volatile long *)addr) : "Ir" (nr) : "memory");
|
|
return oldbit != 0;
|
|
}
|
|
|
|
/* *
|
|
* test_and_change_bit - Atomically change a bit and return its old value
|
|
* @nr: the bit to change
|
|
* @addr: the address to count from
|
|
* */
|
|
static inline bool
|
|
test_and_change_bit(int nr, volatile void *addr) {
|
|
int oldbit;
|
|
asm volatile ("btcl %2, %1; sbbl %0, %0" : "=r" (oldbit), "=m" (*(volatile long *)addr) : "Ir" (nr) : "memory");
|
|
return oldbit != 0;
|
|
}
|
|
|
|
/* *
|
|
* test_bit - Determine whether a bit is set
|
|
* @nr: the bit to test
|
|
* @addr: the address to count from
|
|
* */
|
|
static inline bool
|
|
test_bit(int nr, volatile void *addr) {
|
|
int oldbit;
|
|
asm volatile ("btl %2, %1; sbbl %0,%0" : "=r" (oldbit) : "m" (*(volatile long *)addr), "Ir" (nr));
|
|
return oldbit != 0;
|
|
}
|
|
|
|
#endif /* !__LIBS_ATOMIC_H__ */
|
|
|