Re: [PATCH] s390: Hypervisor File System

["Jörn Engel" <joern@wohnheim.fh-wedel.de>]

On Fri, 28 April 2006 11:22:25 +0200, Michael Holzheu wrote:
> +
> +static inline int info_blk_hdr__size(enum diag204_format type)
> +{
> +	if (type == INFO_SIMPLE)
> +		return sizeof(struct info_blk_hdr);
> +	else /* INFO_EXT */
> +		return sizeof(struct x_info_blk_hdr);
> +}
> +
> +static inline __u8 info_blk_hdr__npar(enum diag204_format type, void *hdr)
> +{
> +	if (type == INFO_SIMPLE)
> +		return ((struct info_blk_hdr *)hdr)->npar;
> +	else /* INFO_EXT */
> +		return ((struct x_info_blk_hdr *)hdr)->npar;
> +}
> +
> +static inline __u8 info_blk_hdr__flags(enum diag204_format type, void *hdr)
> +{
> +	if (type == INFO_SIMPLE)
> +		return ((struct info_blk_hdr *)hdr)->flags;
> +	else /* INFO_EXT */
> +		return ((struct x_info_blk_hdr *)hdr)->flags;
> +}
> +
> +static inline __u16 info_blk_hdr__pcpus(enum diag204_format type, void *hdr)
> +{
> +	if (type == INFO_SIMPLE)
> +		return ((struct info_blk_hdr *)hdr)->phys_cpus;
> +	else /* INFO_EXT */
> +		return ((struct x_info_blk_hdr *)hdr)->phys_cpus;
> +}

Hmm.  Another possible approach would be to create a small struct with
a couple of functions, have one function each for type==INFO_SIMPLE
and type==INFO_EXT and fill the struct either with one set of
functions or the other.

Whether that would make more sense than your current approach, I
cannot judge.  Iirc, function calls are still fairly expensive on
s390, so maybe not.

Jörn

-- 
Courage is not the absence of fear, but rather the judgement that
something else is more important than fear.
-- Ambrose Redmoon