Re: [PATCH 01/12] lib: create common ascii hex array

[Harvey Harrison <harvey.harrison@gmail.com>]

On Tue, 2008-05-13 at 12:55 +0300, Ilpo Järvinen wrote:
> On Mon, 12 May 2008, Harvey Harrison wrote:
> 
> > Add a common hex array in hexdump.c so everyone can use it.
> > 
> > Add a common hi/lo helper to avoid the shifting masking that is
> > done to get the upper and lower nibbles of a byte value.
> > 
> > Pull the pack_hex_byte helper from kgdb as it is opencoded many
> > places in the tree that will be consolidated.
> > 
> > Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
> > ---
> >  
> > -#define hex_asc(x)	"0123456789abcdef"[x]
> > +
> > +extern const char hex_asc[];
> > +#define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
> > +#define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
> > +
> > +static inline char *pack_hex_byte(char *buf, u8 byte)
> > +{
> > +	*buf++ = hex_asc_hi(byte);
> > +	*buf++ = hex_asc_lo(byte);
> > +	return buf;
> > +}
> 
> Any idea how much this will bloat kernel once it has, lets say 100 
> users? 5k, 10k?
> 

No more than the existing users do open-coding the same thing all over
the place.  If it becomes a problem, this can be out-of-lined, but
the savings are not much.

Harvey