Re: [PATCH] vmallocinfo: Add NUMA informations

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 9 Jun 2008 07:16:48 -0700 (PDT)
Christoph Lameter <clameter@sgi.com> wrote:

> On Tue, 3 Jun 2008, Andrew Morton wrote:
> 
> > > +	if (NUMA_BUILD) {
> > > +		unsigned int *counters, nr;
> > > +
> > > +		counters = kzalloc(nr_node_ids * sizeof(unsigned int),
> > 
> > This is kcalloc().  If you like that sorts of thing - I think kcalloc()
> > is pretty pointless personally.
> 
> Same here. I think its generally ignored. I tried to remove it at some 
> point in the past. If we want kcalloc then we also need kczalloc.

kcalloc() zeroes the returned memory - it's like calloc().

> It would 
> be best to keep the interface simple.

yup.  Oh well, it's not a big deal.

Except the inlined

        if (n != 0 && size > ULONG_MAX / n)
                return NULL;

is a bit bloaty/inefficient.  I expect that it's often the case that
one of `n' and `size' is not a compile-time constant.

otoh, there's one good thing about kcalloc: it actually checks for
multiplicative overflows, whereas the open-coded version often forgets
to do that.