| #ifndef _ASM_X86_ATOMIC_32_H |
| #define _ASM_X86_ATOMIC_32_H |
| |
| #include <linux/compiler.h> |
| #include <linux/types.h> |
| #include <asm/processor.h> |
| #include <asm/cmpxchg.h> |
| |
| /* |
| * Atomic operations that C can't guarantee us. Useful for |
| * resource counting etc.. |
| */ |
| |
| #define ATOMIC_INIT(i) { (i) } |
| |
| /** |
| * atomic_read - read atomic variable |
| * @v: pointer of type atomic_t |
| * |
| * Atomically reads the value of @v. |
| */ |
| #define atomic_read(v) ((v)->counter) |
| |
| /** |
| * atomic_set - set atomic variable |
| * @v: pointer of type atomic_t |
| * @i: required value |
| * |
| * Atomically sets the value of @v to @i. |
| */ |
| #define atomic_set(v, i) (((v)->counter) = (i)) |
| |
| /** |
| * atomic_add - add integer to atomic variable |
| * @i: integer value to add |
| * @v: pointer of type atomic_t |
| * |
| * Atomically adds @i to @v. |
| */ |
| static inline void atomic_add(int i, atomic_t *v) |
| { |
| asm volatile(LOCK_PREFIX "addl %1,%0" |
| : "+m" (v->counter) |
| : "ir" (i)); |
| } |
| |
| /** |
| * atomic_sub - subtract integer from atomic variable |
| * @i: integer value to subtract |
| * @v: pointer of type atomic_t |
| * |
| * Atomically subtracts @i from @v. |
| */ |
| static inline void atomic_sub(int i, atomic_t *v) |
| { |
| asm volatile(LOCK_PREFIX "subl %1,%0" |
| : "+m" (v->counter) |
| : "ir" (i)); |
| } |
| |
| /** |
| * atomic_sub_and_test - subtract value from variable and test result |
| * @i: integer value to subtract |
| * @v: pointer of type atomic_t |
| * |
| * Atomically subtracts @i from @v and returns |
| * true if the result is zero, or false for all |
| * other cases. |
| */ |
| static inline int atomic_sub_and_test(int i, atomic_t *v) |
| { |
| unsigned char c; |
| |
| asm volatile(LOCK_PREFIX "subl %2,%0; sete %1" |
| : "+m" (v->counter), "=qm" (c) |
| : "ir" (i) : "memory"); |
| return c; |
| } |
| |
| /** |
| * 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(LOCK_PREFIX "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(LOCK_PREFIX "decl %0" |
| : "+m" (v->counter)); |
| } |
| |
| /** |
| * atomic_dec_and_test - 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 int atomic_dec_and_test(atomic_t *v) |
| { |
| unsigned char c; |
| |
| asm volatile(LOCK_PREFIX "decl %0; sete %1" |
| : "+m" (v->counter), "=qm" (c) |
| : : "memory"); |
| return c != 0; |
| } |
| |
| /** |
| * atomic_inc_and_test - 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 int atomic_inc_and_test(atomic_t *v) |
| { |
| unsigned char c; |
| |
| asm volatile(LOCK_PREFIX "incl %0; sete %1" |
| : "+m" (v->counter), "=qm" (c) |
| : : "memory"); |
| return c != 0; |
| } |
| |
| /** |
| * atomic_add_negative - add and test if negative |
| * @v: pointer of type atomic_t |
| * @i: integer value to add |
| * |
| * Atomically adds @i to @v and returns true |
| * if the result is negative, or false when |
| * result is greater than or equal to zero. |
| */ |
| static inline int atomic_add_negative(int i, atomic_t *v) |
| { |
| unsigned char c; |
| |
| asm volatile(LOCK_PREFIX "addl %2,%0; sets %1" |
| : "+m" (v->counter), "=qm" (c) |
| : "ir" (i) : "memory"); |
| return c; |
| } |
| |
| /** |
| * atomic_add_return - add integer and return |
| * @v: pointer of type atomic_t |
| * @i: integer value to add |
| * |
| * Atomically adds @i to @v and returns @i + @v |
| */ |
| static inline int atomic_add_return(int i, atomic_t *v) |
| { |
| int __i; |
| #ifdef CONFIG_M386 |
| unsigned long flags; |
| if (unlikely(boot_cpu_data.x86 <= 3)) |
| goto no_xadd; |
| #endif |
| /* Modern 486+ processor */ |
| __i = i; |
| asm volatile(LOCK_PREFIX "xaddl %0, %1" |
| : "+r" (i), "+m" (v->counter) |
| : : "memory"); |
| return i + __i; |
| |
| #ifdef CONFIG_M386 |
| no_xadd: /* Legacy 386 processor */ |
| local_irq_save(flags); |
| __i = atomic_read(v); |
| atomic_set(v, i + __i); |
| local_irq_restore(flags); |
| return i + __i; |
| #endif |
| } |
| |
| /** |
| * 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(int i, atomic_t *v) |
| { |
| return atomic_add_return(-i, v); |
| } |
| |
| #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new))) |
| #define atomic_xchg(v, new) (xchg(&((v)->counter), (new))) |
| |
| /** |
| * atomic_add_unless - add unless the number is already a given value |
| * @v: pointer of type atomic_t |
| * @a: the amount to add to v... |
| * @u: ...unless v is equal to u. |
| * |
| * Atomically adds @a to @v, so long as @v was not already @u. |
| * Returns non-zero if @v was not @u, and zero otherwise. |
| */ |
| static inline int atomic_add_unless(atomic_t *v, int a, int u) |
| { |
| int c, old; |
| c = atomic_read(v); |
| for (;;) { |
| if (unlikely(c == (u))) |
| break; |
| old = atomic_cmpxchg((v), c, c + (a)); |
| if (likely(old == c)) |
| break; |
| c = old; |
| } |
| return c != (u); |
| } |
| |
| #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) |
| |
| #define atomic_inc_return(v) (atomic_add_return(1, v)) |
| #define atomic_dec_return(v) (atomic_sub_return(1, v)) |
| |
| /* These are x86-specific, used by some header files */ |
| #define atomic_clear_mask(mask, addr) \ |
| asm volatile(LOCK_PREFIX "andl %0,%1" \ |
| : : "r" (~(mask)), "m" (*(addr)) : "memory") |
| |
| #define atomic_set_mask(mask, addr) \ |
| asm volatile(LOCK_PREFIX "orl %0,%1" \ |
| : : "r" (mask), "m" (*(addr)) : "memory") |
| |
| /* Atomic operations are already serializing on x86 */ |
| #define smp_mb__before_atomic_dec() barrier() |
| #define smp_mb__after_atomic_dec() barrier() |
| #define smp_mb__before_atomic_inc() barrier() |
| #define smp_mb__after_atomic_inc() barrier() |
| |
| /* An 64bit atomic type */ |
| |
| typedef struct { |
| unsigned long long counter; |
| } atomic64_t; |
| |
| #define ATOMIC64_INIT(val) { (val) } |
| |
| /** |
| * atomic64_read - read atomic64 variable |
| * @v: pointer of type atomic64_t |
| * |
| * Atomically reads the value of @v. |
| * Doesn't imply a read memory barrier. |
| */ |
| #define __atomic64_read(ptr) ((ptr)->counter) |
| |
| static inline unsigned long long |
| cmpxchg8b(unsigned long long *ptr, unsigned long long old, unsigned long long new) |
| { |
| asm volatile( |
| |
| LOCK_PREFIX "cmpxchg8b (%[ptr])\n" |
| |
| : "=A" (old) |
| |
| : [ptr] "D" (ptr), |
| "A" (old), |
| "b" (ll_low(new)), |
| "c" (ll_high(new)) |
| |
| : "memory"); |
| |
| return old; |
| } |
| |
| static inline unsigned long long |
| atomic64_cmpxchg(atomic64_t *ptr, unsigned long long old_val, |
| unsigned long long new_val) |
| { |
| return cmpxchg8b(&ptr->counter, old_val, new_val); |
| } |
| |
| /** |
| * atomic64_xchg - xchg atomic64 variable |
| * @ptr: pointer to type atomic64_t |
| * @new_val: value to assign |
| * @old_val: old value that was there |
| * |
| * Atomically xchgs the value of @ptr to @new_val and returns |
| * the old value. |
| */ |
| |
| static inline unsigned long long |
| atomic64_xchg(atomic64_t *ptr, unsigned long long new_val) |
| { |
| unsigned long long old_val; |
| |
| do { |
| old_val = atomic_read(ptr); |
| } while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val); |
| |
| return old_val; |
| } |
| |
| /** |
| * atomic64_set - set atomic64 variable |
| * @ptr: pointer to type atomic64_t |
| * @new_val: value to assign |
| * |
| * Atomically sets the value of @ptr to @new_val. |
| */ |
| static inline void atomic64_set(atomic64_t *ptr, unsigned long long new_val) |
| { |
| atomic64_xchg(ptr, new_val); |
| } |
| |
| /** |
| * atomic64_read - read atomic64 variable |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically reads the value of @ptr and returns it. |
| */ |
| static inline unsigned long long atomic64_read(atomic64_t *ptr) |
| { |
| unsigned long long curr_val; |
| |
| do { |
| curr_val = __atomic64_read(ptr); |
| } while (atomic64_cmpxchg(ptr, curr_val, curr_val) != curr_val); |
| |
| return curr_val; |
| } |
| |
| /** |
| * atomic64_add_return - add and return |
| * @delta: integer value to add |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically adds @delta to @ptr and returns @delta + *@ptr |
| */ |
| static inline unsigned long long |
| atomic64_add_return(unsigned long long delta, atomic64_t *ptr) |
| { |
| unsigned long long old_val, new_val; |
| |
| do { |
| old_val = atomic_read(ptr); |
| new_val = old_val + delta; |
| |
| } while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val); |
| |
| return new_val; |
| } |
| |
| static inline long atomic64_sub_return(unsigned long long delta, atomic64_t *ptr) |
| { |
| return atomic64_add_return(-delta, ptr); |
| } |
| |
| static inline long atomic64_inc_return(atomic64_t *ptr) |
| { |
| return atomic64_add_return(1, ptr); |
| } |
| |
| static inline long atomic64_dec_return(atomic64_t *ptr) |
| { |
| return atomic64_sub_return(1, ptr); |
| } |
| |
| /** |
| * atomic64_add - add integer to atomic64 variable |
| * @delta: integer value to add |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically adds @delta to @ptr. |
| */ |
| static inline void atomic64_add(unsigned long long delta, atomic64_t *ptr) |
| { |
| atomic64_add_return(delta, ptr); |
| } |
| |
| /** |
| * atomic64_sub - subtract the atomic64 variable |
| * @delta: integer value to subtract |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically subtracts @delta from @ptr. |
| */ |
| static inline void atomic64_sub(unsigned long long delta, atomic64_t *ptr) |
| { |
| atomic64_add(-delta, ptr); |
| } |
| |
| /** |
| * atomic64_sub_and_test - subtract value from variable and test result |
| * @delta: integer value to subtract |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically subtracts @delta from @ptr and returns |
| * true if the result is zero, or false for all |
| * other cases. |
| */ |
| static inline int |
| atomic64_sub_and_test(unsigned long long delta, atomic64_t *ptr) |
| { |
| unsigned long long old_val = atomic64_sub_return(delta, ptr); |
| |
| return old_val == 0; |
| } |
| |
| /** |
| * atomic64_inc - increment atomic64 variable |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically increments @ptr by 1. |
| */ |
| static inline void atomic64_inc(atomic64_t *ptr) |
| { |
| atomic64_add(1, ptr); |
| } |
| |
| /** |
| * atomic64_dec - decrement atomic64 variable |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically decrements @ptr by 1. |
| */ |
| static inline void atomic64_dec(atomic64_t *ptr) |
| { |
| atomic64_sub(1, ptr); |
| } |
| |
| /** |
| * atomic64_dec_and_test - decrement and test |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically decrements @ptr by 1 and |
| * returns true if the result is 0, or false for all other |
| * cases. |
| */ |
| static inline int atomic64_dec_and_test(atomic64_t *ptr) |
| { |
| return atomic64_sub_and_test(1, ptr); |
| } |
| |
| /** |
| * atomic64_inc_and_test - increment and test |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically increments @ptr by 1 |
| * and returns true if the result is zero, or false for all |
| * other cases. |
| */ |
| static inline int atomic64_inc_and_test(atomic64_t *ptr) |
| { |
| return atomic64_sub_and_test(-1, ptr); |
| } |
| |
| /** |
| * atomic64_add_negative - add and test if negative |
| * @delta: integer value to add |
| * @ptr: pointer to type atomic64_t |
| * |
| * Atomically adds @delta to @ptr and returns true |
| * if the result is negative, or false when |
| * result is greater than or equal to zero. |
| */ |
| static inline int |
| atomic64_add_negative(unsigned long long delta, atomic64_t *ptr) |
| { |
| long long old_val = atomic64_add_return(delta, ptr); |
| |
| return old_val < 0; |
| } |
| |
| #include <asm-generic/atomic-long.h> |
| #endif /* _ASM_X86_ATOMIC_32_H */ |