Re: [PATCH 3/23] make atomic_read() and atomic_set() behavior consistent on arm

[Russell King]

On Mon, Aug 13, 2007 at 07:09:46AM -0400, Chris Snook wrote:
> From: Chris Snook <csnook@xxxxxxxxxx>
> 
> Use volatile consistently in atomic.h on arm.
> 
> Signed-off-by: Chris Snook <csnook@xxxxxxxxxx>
> 
> --- linux-2.6.23-rc3-orig/include/asm-arm/atomic.h	2007-07-08 19:32:17.000000000 -0400
> +++ linux-2.6.23-rc3/include/asm-arm/atomic.h	2007-08-13 04:44:50.000000000 -0400
> @@ -14,13 +14,16 @@
>  #include <linux/compiler.h>
>  #include <asm/system.h>
>  
> -typedef struct { volatile int counter; } atomic_t;
> +typedef struct { int counter; } atomic_t;
>  
>  #define ATOMIC_INIT(i)	{ (i) }
>  
>  #ifdef __KERNEL__
>  
> -#define atomic_read(v)	((v)->counter)
> +static inline int atomic_read(atomic_t *v)
> +{
> +        return *(volatile int *)&v->counter;
> +}
>  
>  #if __LINUX_ARM_ARCH__ >= 6
>  

...
In the first email of the series:
> By popular demand, I've redone the patchset to include volatile casts in
> atomic_set as well.  I've also converted the macros to inline functions, to
> help catch type mismatches at compile time.

and in the rest of include/asm-arm/atomic.h:

#else /* ARM_ARCH_6 */

#include <asm/system.h>

#ifdef CONFIG_SMP
#error SMP not supported on pre-ARMv6 CPUs
#endif

#define atomic_set(v,i) (((v)->counter) = (i))

Seems you missed that.  Grep is a wonderful tool.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:
-
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