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Diffstat (limited to 'arch/sh/include/asm/mutex-llsc.h')
-rw-r--r-- | arch/sh/include/asm/mutex-llsc.h | 109 |
1 files changed, 0 insertions, 109 deletions
diff --git a/arch/sh/include/asm/mutex-llsc.h b/arch/sh/include/asm/mutex-llsc.h deleted file mode 100644 index dad29b687bd3..000000000000 --- a/arch/sh/include/asm/mutex-llsc.h +++ /dev/null @@ -1,109 +0,0 @@ -/* - * arch/sh/include/asm/mutex-llsc.h - * - * SH-4A optimized mutex locking primitives - * - * Please look into asm-generic/mutex-xchg.h for a formal definition. - */ -#ifndef __ASM_SH_MUTEX_LLSC_H -#define __ASM_SH_MUTEX_LLSC_H - -/* - * Attempting to lock a mutex on SH4A is done like in ARMv6+ architecure. - * with a bastardized atomic decrement (it is not a reliable atomic decrement - * but it satisfies the defined semantics for our purpose, while being - * smaller and faster than a real atomic decrement or atomic swap. - * The idea is to attempt decrementing the lock value only once. If once - * decremented it isn't zero, or if its store-back fails due to a dispute - * on the exclusive store, we simply bail out immediately through the slow - * path where the lock will be reattempted until it succeeds. - */ -static inline void -__mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *)) -{ - int __done, __res; - - __asm__ __volatile__ ( - "movli.l @%2, %0 \n" - "add #-1, %0 \n" - "movco.l %0, @%2 \n" - "movt %1 \n" - : "=&z" (__res), "=&r" (__done) - : "r" (&(count)->counter) - : "t"); - - if (unlikely(!__done || __res != 0)) - fail_fn(count); -} - -static inline int -__mutex_fastpath_lock_retval(atomic_t *count) -{ - int __done, __res; - - __asm__ __volatile__ ( - "movli.l @%2, %0 \n" - "add #-1, %0 \n" - "movco.l %0, @%2 \n" - "movt %1 \n" - : "=&z" (__res), "=&r" (__done) - : "r" (&(count)->counter) - : "t"); - - if (unlikely(!__done || __res != 0)) - __res = -1; - - return __res; -} - -static inline void -__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) -{ - int __done, __res; - - __asm__ __volatile__ ( - "movli.l @%2, %0 \n\t" - "add #1, %0 \n\t" - "movco.l %0, @%2 \n\t" - "movt %1 \n\t" - : "=&z" (__res), "=&r" (__done) - : "r" (&(count)->counter) - : "t"); - - if (unlikely(!__done || __res <= 0)) - fail_fn(count); -} - -/* - * If the unlock was done on a contended lock, or if the unlock simply fails - * then the mutex remains locked. - */ -#define __mutex_slowpath_needs_to_unlock() 1 - -/* - * For __mutex_fastpath_trylock we do an atomic decrement and check the - * result and put it in the __res variable. - */ -static inline int -__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) -{ - int __res, __orig; - - __asm__ __volatile__ ( - "1: movli.l @%2, %0 \n\t" - "dt %0 \n\t" - "movco.l %0,@%2 \n\t" - "bf 1b \n\t" - "cmp/eq #0,%0 \n\t" - "bt 2f \n\t" - "mov #0, %1 \n\t" - "bf 3f \n\t" - "2: mov #1, %1 \n\t" - "3: " - : "=&z" (__orig), "=&r" (__res) - : "r" (&count->counter) - : "t"); - - return __res; -} -#endif /* __ASM_SH_MUTEX_LLSC_H */ |