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author | Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> | 2008-02-07 00:16:13 -0800 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-07 08:42:31 -0800 |
commit | 10b8827068377a11ed0e396248f7d02751fe5f17 (patch) | |
tree | 2ca6e89cc47354ac2cec717e186ede7f24e0b8fd | |
parent | 5e86c11d3eb4662000f3ced7344352b2ca319d03 (diff) | |
download | op-kernel-dev-10b8827068377a11ed0e396248f7d02751fe5f17.zip op-kernel-dev-10b8827068377a11ed0e396248f7d02751fe5f17.tar.gz |
Add cmpxchg_local to blackfin, replace __cmpxchg by generic cmpxchg
Use the new generic cmpxchg_local (disables interrupt). Also use the generic
cmpxchg as fallback if SMP is not set since nobody seems to know why __cmpxchg
has been implemented in assembly in the first place thather than in plain C.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Michael Frysinger <michael.frysinger@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | include/asm-blackfin/system.h | 57 |
1 files changed, 11 insertions, 46 deletions
diff --git a/include/asm-blackfin/system.h b/include/asm-blackfin/system.h index 4a92737..51494ef 100644 --- a/include/asm-blackfin/system.h +++ b/include/asm-blackfin/system.h @@ -183,55 +183,20 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, return tmp; } +#include <asm-generic/cmpxchg-local.h> + /* - * Atomic compare and exchange. Compare OLD with MEM, if identical, - * store NEW in MEM. Return the initial value in MEM. Success is - * indicated by comparing RETURN with OLD. + * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make + * them available. */ -static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, - unsigned long new, int size) -{ - unsigned long tmp = 0; - unsigned long flags = 0; - - local_irq_save(flags); - - switch (size) { - case 1: - __asm__ __volatile__ - ("%0 = b%3 (z);\n\t" - "CC = %1 == %0;\n\t" - "IF !CC JUMP 1f;\n\t" - "b%3 = %2;\n\t" - "1:\n\t" - : "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory"); - break; - case 2: - __asm__ __volatile__ - ("%0 = w%3 (z);\n\t" - "CC = %1 == %0;\n\t" - "IF !CC JUMP 1f;\n\t" - "w%3 = %2;\n\t" - "1:\n\t" - : "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory"); - break; - case 4: - __asm__ __volatile__ - ("%0 = %3;\n\t" - "CC = %1 == %0;\n\t" - "IF !CC JUMP 1f;\n\t" - "%3 = %2;\n\t" - "1:\n\t" - : "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory"); - break; - } - local_irq_restore(flags); - return tmp; -} +#define cmpxchg_local(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ + (unsigned long)(n), sizeof(*(ptr)))) +#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) -#define cmpxchg(ptr,o,n)\ - ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ - (unsigned long)(n),sizeof(*(ptr)))) +#ifndef CONFIG_SMP +#include <asm-generic/cmpxchg.h> +#endif #define prepare_to_switch() do { } while(0) |