Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751298AbWCTSv4 (ORCPT ); Mon, 20 Mar 2006 13:51:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751297AbWCTSv4 (ORCPT ); Mon, 20 Mar 2006 13:51:56 -0500 Received: from warden-p.diginsite.com ([208.29.163.248]:59033 "HELO warden.diginsite.com") by vger.kernel.org with SMTP id S1751281AbWCTSvz (ORCPT ); Mon, 20 Mar 2006 13:51:55 -0500 Date: Mon, 20 Mar 2006 10:44:00 -0800 (PST) From: David Lang X-X-Sender: dlang@dlang.diginsite.com To: Pekka Enberg cc: Benjamin LaHaise , Oliver Neukum , linux-kernel@vger.kernel.org, Adrian Bunk Subject: Re: [PATCH]micro optimization of kcalloc In-Reply-To: <84144f020603200815o66cb689cv239cbe190f9e6f30@mail.gmail.com> Message-ID: References: <20060320151433.GE16108@kvack.org> <84144f020603200815o66cb689cv239cbe190f9e6f30@mail.gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1312 Lines: 35 On Mon, 20 Mar 2006, Pekka Enberg wrote: > Hi, > > On Mon, Mar 20, 2006 at 03:45:23PM +0100, Oliver Neukum wrote: >>> static inline void *kcalloc(size_t n, size_t size, gfp_t flags) >>> { >>> - if (n != 0 && size > INT_MAX / n) >>> + if (unlikely(size != 0 && n > INT_MAX / size )) >>> return NULL; >>> return kzalloc(n * size, flags); >>> } > > On 3/20/06, Benjamin LaHaise wrote: >> This function shouldn't be inlined. We have no need to optimize the >> unlikely case like this. > > IIRC, I made it static inline in the first place because that actually > reduced kernel text size. (And I think it was Adrian who made me do it > :-). I wonder if this is still needed with the new inline changes that were made to allow GCC to make the decision (for recent GCC's) David Lang -- There are two ways of constructing a software design. One way is to make it so simple that there are obviously no deficiencies. And the other way is to make it so complicated that there are no obvious deficiencies. -- C.A.R. Hoare - 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/