From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935058AbYD1O6v (ORCPT ); Mon, 28 Apr 2008 10:58:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750993AbYD1O6o (ORCPT ); Mon, 28 Apr 2008 10:58:44 -0400 Received: from out4.smtp.messagingengine.com ([66.111.4.28]:35801 "EHLO out4.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933507AbYD1O6n (ORCPT ); Mon, 28 Apr 2008 10:58:43 -0400 Message-Id: <1209394723.22937.1250267923@webmail.messagingengine.com> X-Sasl-Enc: 2O3UWmgyH7QBggOJU0zS+djJRvg/8XJP7iGTbW9sXWyP 1209394723 From: "Alexander van Heukelum" To: "Linus Torvalds" , "Harvey Harrison" , "David S. Miller" Cc: "Ingo Molnar" , "Andrew Morton" , "LKML" Content-Disposition: inline Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="ISO-8859-1" MIME-Version: 1.0 X-Mailer: MessagingEngine.com Webmail Interface References: <1209327591.14173.74.camel@brick> Subject: Re: [PATCH] bitops: simplify generic bit finding functions In-Reply-To: Date: Mon, 28 Apr 2008 16:58:43 +0200 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 27 Apr 2008 13:26:34 -0700 (PDT), "Linus Torvalds" said: > On Sun, 27 Apr 2008, Harvey Harrison wrote: > > > > No need for a sentinal if we explicitly catch the no bits/all bits set > > cases, make it clear they are special cases returning size/BITS_PER_LONG. > > These things need to be re-done anyway. David already complained that the > thing inlines to something much much too big. > > Let's just make it not be an inline at all. Hello, I think that's the wrong way to go about it. The problem that David Miller pointed out was that the small-bitmap optimization caused an inliningdisaster. Apparently, the generic version of __ffs is very big on sparc64. In my opinion the implementation of __ffs should be made out of line. If you move the wrapper of find_first_bit etc out of line, all possibilities of optimization will be destroyed. Better to remove them completely, then. Greetings, Alexander > Linus > -- > 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/ > > -- Alexander van Heukelum heukelum@fastmail.fm -- http://www.fastmail.fm - Accessible with your email software or over the web