Re: [PATCH] atomic: fix atomic_long_cmpxchg/xchg for 64 bit architectures

[Ingo Molnar <mingo@elte.hu>]

* Heiko Carstens <heiko.carstens@de.ibm.com> wrote:

> From: Heiko Carstens <heiko.carstens@de.ibm.com>
> 
> On a linux-next allyesconfig build:
> 
> kernel/trace/ring_buffer.c:1726:
> 	warning: passing argument 1 of 'atomic_cmpxchg' from incompatible pointer type
> linux-next/arch/s390/include/asm/atomic.h:112:
> 	note: expected 'struct atomic_t *' but argument is of type 'struct atomic64_t *'
> 
> atomic_long_cmpxchg and atomic_long_xchg are incorrectly defined for
> 64 bit architectures. They should be mapped to the atomic64_* variants.
> 
> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
> ---
>  include/asm-generic/atomic.h |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> Index: linux-next/include/asm-generic/atomic.h
> ===================================================================
> --- linux-next.orig/include/asm-generic/atomic.h
> +++ linux-next/include/asm-generic/atomic.h
> @@ -132,9 +132,9 @@ static inline long atomic_long_add_unles
>  #define atomic_long_inc_not_zero(l) atomic64_inc_not_zero((atomic64_t *)(l))
>  
>  #define atomic_long_cmpxchg(l, old, new) \
> -	(atomic_cmpxchg((atomic64_t *)(l), (old), (new)))
> +	(atomic64_cmpxchg((atomic64_t *)(l), (old), (new)))
>  #define atomic_long_xchg(v, new) \
> -	(atomic_xchg((atomic64_t *)(l), (new)))
> +	(atomic64_xchg((atomic64_t *)(l), (new)))

Acked-by: Ingo Molnar <mingo@elte.hu>

That's due to the local_cmpchg() use the tracing tree grew recently, 
right? It appears it was never used in generic code before.

	Ingo