Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935103AbXHNXFd (ORCPT ); Tue, 14 Aug 2007 19:05:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752462AbXHNXFS (ORCPT ); Tue, 14 Aug 2007 19:05:18 -0400 Received: from shawidc-mo1.cg.shawcable.net ([24.71.223.10]:10221 "EHLO pd2mo3so.prod.shaw.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752060AbXHNXFQ (ORCPT ); Tue, 14 Aug 2007 19:05:16 -0400 Date: Tue, 14 Aug 2007 17:05:04 -0600 From: Robert Hancock Subject: Re: kfree(0) - ok? In-reply-to: To: Tim Bird Cc: linux kernel Message-id: <46C23520.2070805@shaw.ca> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit References: User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 960 Lines: 27 Tim Bird wrote: > Hi all, > > I have a quick question. > > I'm trying to resurrect a patch from the Linux-tiny patch suite, > to do accounting of kmalloc memory allocations. In testing it > with Linux 2.6.22, I've found a large number of kfrees of > NULL pointers. > > Is this considered OK? Or should I examine the offenders > to see if something is coded badly? It's perfectly correct to do it - though, if it's done very frequently in certain cases, it might be more efficient to check for null before the kfree, to avoid the function call overhead into kfree.. -- Robert Hancock Saskatoon, SK, Canada To email, remove "nospam" from hancockr@nospamshaw.ca Home Page: http://www.roberthancock.com/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/