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Diffstat (limited to 'arch/x86/include/asm/mutex_64.h')
-rw-r--r-- | arch/x86/include/asm/mutex_64.h | 127 |
1 files changed, 0 insertions, 127 deletions
diff --git a/arch/x86/include/asm/mutex_64.h b/arch/x86/include/asm/mutex_64.h deleted file mode 100644 index d9850758464e..000000000000 --- a/arch/x86/include/asm/mutex_64.h +++ /dev/null @@ -1,127 +0,0 @@ -/* - * Assembly implementation of the mutex fastpath, based on atomic - * decrement/increment. - * - * started by Ingo Molnar: - * - * Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> - */ -#ifndef _ASM_X86_MUTEX_64_H -#define _ASM_X86_MUTEX_64_H - -/** - * __mutex_fastpath_lock - decrement and call function if negative - * @v: pointer of type atomic_t - * @fail_fn: function to call if the result is negative - * - * Atomically decrements @v and calls <fail_fn> if the result is negative. - */ -#ifdef CC_HAVE_ASM_GOTO -static inline void __mutex_fastpath_lock(atomic_t *v, - void (*fail_fn)(atomic_t *)) -{ - asm_volatile_goto(LOCK_PREFIX " decl %0\n" - " jns %l[exit]\n" - : : "m" (v->counter) - : "memory", "cc" - : exit); - fail_fn(v); -exit: - return; -} -#else -#define __mutex_fastpath_lock(v, fail_fn) \ -do { \ - unsigned long dummy; \ - \ - typecheck(atomic_t *, v); \ - typecheck_fn(void (*)(atomic_t *), fail_fn); \ - \ - asm volatile(LOCK_PREFIX " decl (%%rdi)\n" \ - " jns 1f \n" \ - " call " #fail_fn "\n" \ - "1:" \ - : "=D" (dummy) \ - : "D" (v) \ - : "rax", "rsi", "rdx", "rcx", \ - "r8", "r9", "r10", "r11", "memory"); \ -} while (0) -#endif - -/** - * __mutex_fastpath_lock_retval - try to take the lock by moving the count - * from 1 to a 0 value - * @count: pointer of type atomic_t - * - * Change the count from 1 to a value lower than 1. This function returns 0 - * if the fastpath succeeds, or -1 otherwise. - */ -static inline int __mutex_fastpath_lock_retval(atomic_t *count) -{ - if (unlikely(atomic_dec_return(count) < 0)) - return -1; - else - return 0; -} - -/** - * __mutex_fastpath_unlock - increment and call function if nonpositive - * @v: pointer of type atomic_t - * @fail_fn: function to call if the result is nonpositive - * - * Atomically increments @v and calls <fail_fn> if the result is nonpositive. - */ -#ifdef CC_HAVE_ASM_GOTO -static inline void __mutex_fastpath_unlock(atomic_t *v, - void (*fail_fn)(atomic_t *)) -{ - asm_volatile_goto(LOCK_PREFIX " incl %0\n" - " jg %l[exit]\n" - : : "m" (v->counter) - : "memory", "cc" - : exit); - fail_fn(v); -exit: - return; -} -#else -#define __mutex_fastpath_unlock(v, fail_fn) \ -do { \ - unsigned long dummy; \ - \ - typecheck(atomic_t *, v); \ - typecheck_fn(void (*)(atomic_t *), fail_fn); \ - \ - asm volatile(LOCK_PREFIX " incl (%%rdi)\n" \ - " jg 1f\n" \ - " call " #fail_fn "\n" \ - "1:" \ - : "=D" (dummy) \ - : "D" (v) \ - : "rax", "rsi", "rdx", "rcx", \ - "r8", "r9", "r10", "r11", "memory"); \ -} while (0) -#endif - -#define __mutex_slowpath_needs_to_unlock() 1 - -/** - * __mutex_fastpath_trylock - try to acquire the mutex, without waiting - * - * @count: pointer of type atomic_t - * @fail_fn: fallback function - * - * Change the count from 1 to 0 and return 1 (success), or return 0 (failure) - * if it wasn't 1 originally. [the fallback function is never used on - * x86_64, because all x86_64 CPUs have a CMPXCHG instruction.] - */ -static inline int __mutex_fastpath_trylock(atomic_t *count, - int (*fail_fn)(atomic_t *)) -{ - if (likely(atomic_read(count) == 1 && atomic_cmpxchg(count, 1, 0) == 1)) - return 1; - - return 0; -} - -#endif /* _ASM_X86_MUTEX_64_H */ |