Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758053AbXKGJSL (ORCPT ); Wed, 7 Nov 2007 04:18:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756120AbXKGJRy (ORCPT ); Wed, 7 Nov 2007 04:17:54 -0500 Received: from sa14.bezeqint.net ([192.115.104.29]:46365 "EHLO sa14.bezeqint.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758071AbXKGJRu (ORCPT ); Wed, 7 Nov 2007 04:17:50 -0500 Message-ID: <47318298.2030903@panasas.com> Date: Wed, 07 Nov 2007 11:17:12 +0200 From: Boaz Harrosh User-Agent: Thunderbird 2.0.0.6 (X11/20070728) MIME-Version: 1.0 To: "Robert P. J. Day" CC: Linux Kernel Mailing List Subject: Re: [PATCH] Add the macro to test if "exactly_one_bit_set" to log2.h. References: <4730AE66.6030501@panasas.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1335 Lines: 40 On Tue, Nov 06 2007 at 20:53 +0200, "Robert P. J. Day" wrote: > On Tue, 6 Nov 2007, Boaz Harrosh wrote: > >> On Tue, Nov 06 2007 at 18:38 +0200, "Robert P. J. Day" wrote: >>> While this macro is defined in terms of "is_power_of_2" and is >>> therefore functionally equivalent, the visual semantics are sometimes >>> more appropriate for what is actually being tested. >>> >>> Signed-off-by: Robert P. J. Day >>> >>> --- >>> >>> diff --git a/include/linux/log2.h b/include/linux/log2.h >>> index c8cf5e8..d0d324e 100644 >>> --- a/include/linux/log2.h >>> +++ b/include/linux/log2.h >>> @@ -55,6 +55,12 @@ bool is_power_of_2(unsigned long n) >>> } >>> >>> /* >>> + * And for folks who want slightly different semantics ... >>> + */ >>> + >>> +#define exactly_one_bit_set is_power_of_2 >> at_most_one_bit_set No? > > no, it really is *exactly* one bit set. zero is not considered a > power of two. > > rday Yes, Sorry for the noise it was late and I should have returned to the kids instead of reading lkml. Boaz - 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/