[4/9] powerpc: inline ip_fast_csum()

Scott Wood oss at buserror.net
Sat Mar 5 14:50:54 AEDT 2016


On Tue, Sep 22, 2015 at 04:34:25PM +0200, Christophe Leroy wrote:
> @@ -137,6 +130,45 @@ static inline __wsum csum_add(__wsum csum, __wsum addend)
>  #endif
>  }
>  
> +/*
> + * This is a version of ip_compute_csum() optimized for IP headers,
> + * which always checksum on 4 octet boundaries.  ihl is the number
> + * of 32-bit words and is always >= 5.
> + */
> +static inline __wsum ip_fast_csum_nofold(const void *iph, unsigned int ihl)
> +{
> +	u32 *ptr = (u32 *)iph + 1;

const?

> +#ifdef __powerpc64__
> +	unsigned int i;
> +	u64 s = *(__force u32 *)iph;

const?
Why __force?

> +	s += (s >> 32);
> +	return (__force __wsum)s;
> +
> +#else
> +	__wsum sum, tmp;
> +
> +	asm("mtctr %3;"
> +	    "addc %0,%4,%5;"
> +	    "1:lwzu %1, 4(%2);"
> +	    "adde %0,%0,%1;"
> +	    "bdnz 1b;"
> +	    "addze %0,%0;"
> +	    : "=r"(sum), "=r"(tmp), "+b"(ptr)
> +	    : "r"(ihl - 2), "r"(*(u32 *)iph), "r"(*ptr)
> +	    : "ctr", "xer", "memory");

Space between " and (
Space after :
const in cast

I've fixed these up while applying.

-Scott


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