summaryrefslogtreecommitdiffstats
path: root/arch/sh/include/asm/mutex-llsc.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sh/include/asm/mutex-llsc.h')
-rw-r--r--arch/sh/include/asm/mutex-llsc.h109
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 */