Re: RFC: turn kmalloc+memset(,0,) into kcalloc

From: Paulo Marques
Date: Wed Apr 06 2005 - 10:53:10 EST


Pekka Enberg wrote:
Hi,

On Apr 6, 2005 3:15 PM, Paulo Marques <pmarques@xxxxxxxxxxxx> wrote:

However "calloc" is the standard C interface for doing this, so it makes
some sense to use it here as well... :(


I initally submitted kcalloc() with just one parameter but Arjan
wanted it to be similar to standard calloc() so we could check for
overflows. I don't see any reason not to introduce kzalloc() for the
common case you mentioned (as suggested by Denis).

kzalloc it is, then.

By the way I did a quick measurement to see how much we could gain in kernel size by doing this. This is with a 2.6.11-rc2, defconfig kernel:

with kmalloc+memset:
vmlinuz: 5521614
bzImage: 2005274

with kzalloc:
vmlinuz: 5513422
bzImage: 2003927

So we gain 8kB on the uncompressed image and 1347 bytes on the compressed one. This was just a dumb test and actual results might be better due to smarter human cleanups.

Not a spectacular gain per se, but the increase in code readability is still worth it, IMHO.

--
Paulo Marques - www.grupopie.com

All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke (1729 - 1797)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/