Re: [PATCH v6] hashtable: introduce a small and naive hashtable

From: Steven Rostedt
Date: Wed Sep 26 2012 - 09:59:53 EST


On Wed, 2012-09-26 at 14:45 +0100, David Laight wrote:
> Amazing how something simple gets lots of comments and versions :-)
>
> > ...
> > + * This has to be a macro since HASH_BITS() will not work on pointers since
> > + * it calculates the size during preprocessing.
> > + */
> > +#define hash_empty(hashtable) \
> > +({ \
> > + int __i; \
> > + bool __ret = true; \
> > + \
> > + for (__i = 0; __i < HASH_SIZE(hashtable); __i++) \
> > + if (!hlist_empty(&hashtable[__i])) \
> > + __ret = false; \
> > + \
> > + __ret; \
> > +})
>
> Actually you could have a #define that calls a function
> passing in the address and size.

Probably would be cleaner to do so.


> Also, should the loop have a 'break' in it?

Yeah it should, and could do:

for (i = 0; i < HASH_SIZE(hashtable); i++)
if (!hlist_empty(&hashtable[i]))
break;

return i < HASH_SIZE(hashtable);

-- Steve


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