From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 88031600068 for ; Mon, 4 Jan 2010 01:06:56 -0500 (EST) Received: by pzk27 with SMTP id 27so8460182pzk.12 for ; Sun, 03 Jan 2010 22:06:55 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <4B417A37.7060001@gmail.com> References: <1262571730-2778-1-git-send-email-shijie8@gmail.com> <20100104122138.f54b7659.minchan.kim@barrios-desktop> <4B416A28.70806@gmail.com> <20100104134827.ce642c11.minchan.kim@barrios-desktop> <4B417A37.7060001@gmail.com> Date: Mon, 4 Jan 2010 15:06:54 +0900 Message-ID: <28c262361001032206m6b102f85wed64ae31fd5b06d5@mail.gmail.com> Subject: Re: [PATCH] mm : add check for the return value From: Minchan Kim Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org To: Huang Shijie Cc: akpm@linux-foundation.org, mel@csn.ul.ie, linux-mm@kvack.org, KOSAKI Motohiro List-ID: On Mon, Jan 4, 2010 at 2:18 PM, Huang Shijie wrote: > >> I think the branch itself could not a big deal but 'likely'. >> >> Why I suggest is that now 'if (!page)' don't have 'likely'. >> As you know, 'likely' make the code relocate for reducing code footprint. >> >> Why? It was just mistake or doesn't need it? >> >> > > I think the CPU will CACHE the `likely' code, and make it runs fast. I think so. > > IMHO, "if (unlikely(page == NULL)) " is better then "if (!page)" ,just like > the > code in rmqueue_bulk(). >> I think Mel does know it. >> >> > > wait for Mel's response. Yes. Regardless of Kosaki's patch, there is a issue about likely/unlinkely usage. > -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org