From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id ED8B86B023F for ; Tue, 4 May 2010 13:36:15 -0400 (EDT) Received: by bwz9 with SMTP id 9so2385189bwz.29 for ; Tue, 04 May 2010 10:36:12 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20100420230719.GB1432@n2100.arm.linux.org.uk> References: <20100420155122.6f2c26eb.akpm@linux-foundation.org> <20100420230719.GB1432@n2100.arm.linux.org.uk> From: Marcelo Jimenez Date: Tue, 4 May 2010 14:35:50 -0300 Message-ID: Subject: Re: Suspicious compilation warning Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: Russell King - ARM Linux Cc: Andrew Morton , Stephen Rothwell , Christoph Lameter , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Minchan Kim , KOSAKI Motohiro , "H. Peter Anvin" , Yinghai Lu , linux-arm-kernel@lists.infradead.org List-ID: Hi, On Tue, Apr 20, 2010 at 20:07, Russell King - ARM Linux wrote: > > Well, it'll be about this number on everything using sparsemem extreme: > > #define SECTIONS_PER_ROOT =A0 =A0 =A0 (PAGE_SIZE / sizeof (struct mem_sec= tion)) > > and with only 32 sections, this is going to give a NR_SECTION_ROOTS value > of zero. =A0I think the calculation of NR_SECTIONS_ROOTS is wrong. > > #define NR_SECTION_ROOTS =A0 =A0 =A0 =A0(NR_MEM_SECTIONS / SECTIONS_PER_R= OOT) > > Clearly if we have 1 mem section, we want to have one section root, so > I think this division should round up any fractional part, thusly: > > #define NR_SECTION_ROOTS =A0 =A0 =A0 =A0((NR_MEM_SECTIONS + SECTIONS_PER_= ROOT - 1) / SECTIONS_PER_ROOT) Seems correct to me, Is there any idea when this gets committed? Regards, Marcelo. -- 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