From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King Subject: Re: [BUG] cpufreq on SMP with CPUs present but not online Date: Tue, 18 Jan 2005 19:08:09 +0000 Message-ID: <20050118190809.C18102@flint.arm.linux.org.uk> References: <20050117223827.D31178@flint.arm.linux.org.uk> <20050118180630.GB24734@dominikbrodowski.de> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <20050118180630.GB24734@dominikbrodowski.de>; from linux@dominikbrodowski.de on Tue, Jan 18, 2005 at 07:06:30PM +0100 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=gmane.org@lists.linux.org.uk Content-Type: text/plain; charset="iso-8859-1" To: Dominik Brodowski , Alan Cox Cc: cpufreq@zenII.linux.org.uk On Tue, Jan 18, 2005 at 07:06:30PM +0100, Dominik Brodowski wrote: > On Mon, Jan 17, 2005 at 10:38:27PM +0000, Russell King wrote: > > ... causes the cpufreq driver init method to be called for each CPU. > > However, this causes something of a dilema on ARM/SMP - if the CPU > > is not online (because we failed to bring it up via __cpu_up which > > correctly returned an error), we can't read the current clock rate > > settings, so we can't initialise policy->{cur,min,max} fields. >=20 > Do I understand you correctly that this CPU will be brought up later? Possibly - though I'm wondering whether it's really correct to register the struct cpu for not-currently-online but possible CPUs.=A0 I think this may make sense, but I'd want to get it confirmed by some SMP folk first. > > Returning an error from the cpufreq driver init method means that > > cpufreq completely forgets about this particular CPU, which also > > isn't desirable. > >=20 > > Ideas? >=20 > Yes. I had tried to integrate cpufreq better with the CPU hotplug core a = few > months ago, but got delayed because of other hotplug-related issues which > hopefully will be sorted out very soon. Stay tuned. >=20 > Dominik >=20 > PS: should we all use cpufreq@zenII.linux.org.uk or @lists.linux.org.uk? lists.linux.org.uk please. Unfortunately, when mailservers see the CNAME for lists.linux.org.uk, they rewrite all addresses to the result of the CNAME. Alan - can you change CNAME into: lists IN A 195.92.249.252 IN AAAA 2002:c35c:f9fc::1 please? Thanks. --=20 Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core