diff options
| author | Aoi Shinkai <shinkoi2005@gmail.com> | 2009-06-10 16:15:42 +0000 |
|---|---|---|
| committer | Paul Mundt <lethal@linux-sh.org> | 2009-06-11 09:31:55 +0300 |
| commit | 4c7c99788631bab177bd51e15e893be4689bb085 (patch) | |
| tree | 52e50e0b2a30b31dc8c6460e98279b3c1b47c476 /arch | |
| parent | f168dd00a9440a6f644db73bda47718fd12008e4 (diff) | |
sh: Fix sh4a llsc-based cmpxchg()
This fixes up a typo in the ll/sc based cmpxchg code which apparently
wasn't getting a lot of testing due to the swapped old/new pair. With
that fixed up, the ll/sc code also starts using it and provides its own
atomic_add_unless().
Signed-off-by: Aoi Shinkai <shinkoi2005@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/sh/include/asm/atomic-llsc.h | 27 | ||||
| -rw-r--r-- | arch/sh/include/asm/atomic.h | 4 | ||||
| -rw-r--r-- | arch/sh/include/asm/cmpxchg-llsc.h | 2 | ||||
| -rw-r--r-- | arch/sh/include/asm/spinlock.h | 2 |
4 files changed, 31 insertions, 4 deletions
diff --git a/arch/sh/include/asm/atomic-llsc.h b/arch/sh/include/asm/atomic-llsc.h index 4b00b78e3f4..b040e1e0861 100644 --- a/arch/sh/include/asm/atomic-llsc.h +++ b/arch/sh/include/asm/atomic-llsc.h @@ -104,4 +104,31 @@ static inline void atomic_set_mask(unsigned int mask, atomic_t *v) : "t"); } +#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) + +/** + * atomic_add_unless - add unless the number is 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 it was not @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); +} + #endif /* __ASM_SH_ATOMIC_LLSC_H */ diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h index 6327ffbb199..978b58efb1e 100644 --- a/arch/sh/include/asm/atomic.h +++ b/arch/sh/include/asm/atomic.h @@ -45,7 +45,7 @@ #define atomic_inc(v) atomic_add(1,(v)) #define atomic_dec(v) atomic_sub(1,(v)) -#ifndef CONFIG_GUSA_RB +#if !defined(CONFIG_GUSA_RB) && !defined(CONFIG_CPU_SH4A) static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { int ret; @@ -73,7 +73,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) return ret != u; } -#endif +#endif /* !CONFIG_GUSA_RB && !CONFIG_CPU_SH4A */ #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) diff --git a/arch/sh/include/asm/cmpxchg-llsc.h b/arch/sh/include/asm/cmpxchg-llsc.h index 0fac3da536c..47136661a20 100644 --- a/arch/sh/include/asm/cmpxchg-llsc.h +++ b/arch/sh/include/asm/cmpxchg-llsc.h @@ -55,7 +55,7 @@ __cmpxchg_u32(volatile int *m, unsigned long old, unsigned long new) "mov %0, %1 \n\t" "cmp/eq %1, %3 \n\t" "bf 2f \n\t" - "mov %3, %0 \n\t" + "mov %4, %0 \n\t" "2: \n\t" "movco.l %0, @%2 \n\t" "bf 1b \n\t" diff --git a/arch/sh/include/asm/spinlock.h b/arch/sh/include/asm/spinlock.h index 60283565f89..a28c9f0053f 100644 --- a/arch/sh/include/asm/spinlock.h +++ b/arch/sh/include/asm/spinlock.h @@ -26,7 +26,7 @@ #define __raw_spin_is_locked(x) ((x)->lock <= 0) #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock) #define __raw_spin_unlock_wait(x) \ - do { cpu_relax(); } while ((x)->lock) + do { while (__raw_spin_is_locked(x)) cpu_relax(); } while (0) /* * Simple spin lock operations. There are two variants, one clears IRQ's |