Re: [PATCH 09/11 v2] RDMA/cxgb4: Support on-chip SQs.

[Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>]

On 09/28/2010 12:57 PM, Roland Dreier wrote:
> As I said, I applied this, but I wonder:
>
>   >  +static inline pgprot_t t4_pgprot_wc(pgprot_t prot)
>   >  +{
>   >  +#if defined(__i386__) || defined(__x86_64__)
>   >  +	return pgprot_writecombine(prot);
>   >  +#elif defined(CONFIG_PPC64)
>   >  +	return __pgprot((pgprot_val(prot) | _PAGE_NO_CACHE)&
>   >  +			~(pgprot_t)_PAGE_GUARDED);
>   >  +#else
>   >  +	return pgprot_noncached(prot);
>   >  +#endif
>   >  +}
>   >  +
>   >  +static inline int t4_ocqp_supported(void)
>   >  +{
>   >  +#if defined(__i386__) || defined(__x86_64__) || defined(CONFIG_PPC64)
>   >  +	return 1;
>   >  +#else
>   >  +	return 0;
>   >  +#endif
>   >  +}
>
> Is there any way to avoid this ifdef-ery?  It seems at least the powerpc
> case should be wrapped up in an arch/powerpc version of pgprot_writecombine.
> Also doing this by hand as here leaves out for example ia64, which seems
> to have a definition of pgrprot_writecombine.
>
>    

We would remove it I guess.   I see that mlx4 assumes 
pgprot_writecombine() exists and works correctly across all platforms.  
See mlx4_ib_mmap().

> However I don't know what (if anything) we should do for the
> ocqp_supported test ...
>    

If all platforms support pgprot_writecombine() correctly, then we don't 
need ocqp_supported().

Steve.
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html