From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754032AbYJCIVl (ORCPT ); Fri, 3 Oct 2008 04:21:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751978AbYJCIVZ (ORCPT ); Fri, 3 Oct 2008 04:21:25 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:56113 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751949AbYJCIVY (ORCPT ); Fri, 3 Oct 2008 04:21:24 -0400 Date: Fri, 3 Oct 2008 01:20:03 -0700 From: Andrew Morton To: Pekka Enberg Cc: Christoph Lameter , linux-kernel@vger.kernel.org, linux-mm@kvack.org, rusty@rustcorp.com.au, jeremy@goop.org, ebiederm@xmission.com, travis@sgi.com, herbert@gondor.apana.org.au, xemul@openvz.org Subject: Re: [patch 3/4] cpu alloc: The allocator Message-Id: <20081003012003.f1f84937.akpm@linux-foundation.org> In-Reply-To: <1223019811.30285.12.camel@penberg-laptop> References: <20080929193500.470295078@quilx.com> <20080929193516.278278446@quilx.com> <20081003003342.4d592c1f.akpm@linux-foundation.org> <1223019811.30285.12.camel@penberg-laptop> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 03 Oct 2008 10:43:31 +0300 Pekka Enberg wrote: > Hi Andrew, > > On Fri, 2008-10-03 at 00:33 -0700, Andrew Morton wrote: > > > +static void set_map(int start, int length) > > > +{ > > > + while (length-- > 0) > > > + __set_bit(start++, cpu_alloc_map); > > > +} > > > > Can we use bitmap_fill() here? > > But bitmap_fill() assumes that the starting offset is aligned to > unsigned long (which is not the case here), doesn't it? umm, yeah, the whole bitmap interface is busted from that POV. > ___On Fri, 2008-10-03 at 00:33 -0700, Andrew Morton wrote: > > But I'd have though that it would be possible to only allocate the > > storage for online CPUs. That would be a pretty significant win for > > some system configurations? > > Maybe, but then you'd have to deal with CPU hotplug... iik. Of course. From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 3 Oct 2008 01:20:03 -0700 From: Andrew Morton Subject: Re: [patch 3/4] cpu alloc: The allocator Message-Id: <20081003012003.f1f84937.akpm@linux-foundation.org> In-Reply-To: <1223019811.30285.12.camel@penberg-laptop> References: <20080929193500.470295078@quilx.com> <20080929193516.278278446@quilx.com> <20081003003342.4d592c1f.akpm@linux-foundation.org> <1223019811.30285.12.camel@penberg-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Pekka Enberg Cc: Christoph Lameter , linux-kernel@vger.kernel.org, linux-mm@kvack.org, rusty@rustcorp.com.au, jeremy@goop.org, ebiederm@xmission.com, travis@sgi.com, herbert@gondor.apana.org.au, xemul@openvz.org List-ID: On Fri, 03 Oct 2008 10:43:31 +0300 Pekka Enberg wrote: > Hi Andrew, > > On Fri, 2008-10-03 at 00:33 -0700, Andrew Morton wrote: > > > +static void set_map(int start, int length) > > > +{ > > > + while (length-- > 0) > > > + __set_bit(start++, cpu_alloc_map); > > > +} > > > > Can we use bitmap_fill() here? > > But bitmap_fill() assumes that the starting offset is aligned to > unsigned long (which is not the case here), doesn't it? umm, yeah, the whole bitmap interface is busted from that POV. > ___On Fri, 2008-10-03 at 00:33 -0700, Andrew Morton wrote: > > But I'd have though that it would be possible to only allocate the > > storage for online CPUs. That would be a pretty significant win for > > some system configurations? > > Maybe, but then you'd have to deal with CPU hotplug... iik. Of course. -- 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