From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030285AbWGZAKZ (ORCPT ); Tue, 25 Jul 2006 20:10:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030286AbWGZAKZ (ORCPT ); Tue, 25 Jul 2006 20:10:25 -0400 Received: from ra.tuxdriver.com ([70.61.120.52]:34317 "EHLO ra.tuxdriver.com") by vger.kernel.org with ESMTP id S1030285AbWGZAKY (ORCPT ); Tue, 25 Jul 2006 20:10:24 -0400 Date: Tue, 25 Jul 2006 20:06:12 -0400 From: Neil Horman To: Segher Boessenkool Cc: Paul Mackerras , "H. Peter Anvin" , linux-kernel@vger.kernel.org, a.zummo@towertech.it, jg@freedesktop.org Subject: Re: [PATCH] RTC: Add mmap method to rtc character driver Message-ID: <20060726000612.GC5147@localhost.localdomain> References: <20060725174100.GA4608@hmsreliant.homelinux.net> <03BCDC7F-13D9-42FC-86FC-30C76FD3B3B8@kernel.crashing.org> <20060725182833.GE4608@hmsreliant.homelinux.net> <44C66C91.8090700@zytor.com> <17606.31023.273943.551848@cargo.ozlabs.ibm.com> <5F730DDA-7A1C-4514-873F-9EB37CB7719E@kernel.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5F730DDA-7A1C-4514-873F-9EB37CB7719E@kernel.crashing.org> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 26, 2006 at 01:27:46AM +0200, Segher Boessenkool wrote: > >It's not that bad; if userspace is running, the cpu isn't idle, so > >there isn't the motivation to go tickless on that cpu. In other > >words, if every cpu has suspended ticks, then no cpu can be running > >stuff that needs to look at this page. > > If I read the patch correctly, none of those legacy RTC ticks > can ever be suspended though? > Of course they can. See rtc_do_ioctl, specifically the RTC_UIE_OFF and RTC_PIE_OFF cases. Neil > > Segher