From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arun R Bharadwaj Subject: Re: [v6 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER. Date: Thu, 24 Sep 2009 10:42:41 +0530 Message-ID: <20090924051238.GA5963@linux.vnet.ibm.com> References: <20090922112526.GA7788@linux.vnet.ibm.com> Reply-To: arun@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20090922112526.GA7788@linux.vnet.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+glppd-linuxppc64-dev=m.gmane.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+glppd-linuxppc64-dev=m.gmane.org@lists.ozlabs.org To: Len Brown , Peter Zijlstra , Joel Schopp , Benjamin Herrenschmidt , Paul Mackerras Cc: linux-acpi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org List-Id: linux-acpi@vger.kernel.org * Arun R Bharadwaj [2009-09-22 16:55:27]: Hi Len, (or other acpi folks), I had a question regarding ACPI-cpuidle interaction in the current implementation. Currently, every cpu (i.e. acpi_processor) registers to cpuidle as a cpuidle_device. So every cpu has to go through the process of setting up the idle states and then registering as a cpuidle device. What exactly is the reason behind this? Is this really necessary or can we have a system-wide one-time registering to cpuidle by ACPI? I'm currently in the process of enabling cpuidle for POWER systems and find that having a system-wide registering mechanism to be a cleaner design. --arun From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp08.au.ibm.com (e23smtp08.au.ibm.com [202.81.31.141]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp08.au.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 64B94B7B78 for ; Thu, 24 Sep 2009 15:13:08 +1000 (EST) Received: from d23relay02.au.ibm.com (d23relay02.au.ibm.com [202.81.31.244]) by e23smtp08.au.ibm.com (8.14.3/8.13.1) with ESMTP id n8O56O0s014775 for ; Thu, 24 Sep 2009 15:06:24 +1000 Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay02.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id n8O5D5KJ1077326 for ; Thu, 24 Sep 2009 15:13:05 +1000 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n8O5D3Km029978 for ; Thu, 24 Sep 2009 15:13:04 +1000 Date: Thu, 24 Sep 2009 10:42:41 +0530 From: Arun R Bharadwaj To: Len Brown , Peter Zijlstra , Joel Schopp , Benjamin Herrenschmidt , Paul Mackerras , Ingo Molnar , Vaidyanathan Srinivasan , Dipankar Sarma , Balbir Singh , Gautham R Shenoy , Shaohua Li , Venkatesh Pallipadi , Arun Bharadwaj Subject: Re: [v6 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER. Message-ID: <20090924051238.GA5963@linux.vnet.ibm.com> References: <20090922112526.GA7788@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 In-Reply-To: <20090922112526.GA7788@linux.vnet.ibm.com> Cc: linux-acpi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Reply-To: arun@linux.vnet.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , * Arun R Bharadwaj [2009-09-22 16:55:27]: Hi Len, (or other acpi folks), I had a question regarding ACPI-cpuidle interaction in the current implementation. Currently, every cpu (i.e. acpi_processor) registers to cpuidle as a cpuidle_device. So every cpu has to go through the process of setting up the idle states and then registering as a cpuidle device. What exactly is the reason behind this? Is this really necessary or can we have a system-wide one-time registering to cpuidle by ACPI? I'm currently in the process of enabling cpuidle for POWER systems and find that having a system-wide registering mechanism to be a cleaner design. --arun From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752628AbZIXFNG (ORCPT ); Thu, 24 Sep 2009 01:13:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751849AbZIXFNE (ORCPT ); Thu, 24 Sep 2009 01:13:04 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:58325 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751837AbZIXFNC (ORCPT ); Thu, 24 Sep 2009 01:13:02 -0400 Date: Thu, 24 Sep 2009 10:42:41 +0530 From: Arun R Bharadwaj To: Len Brown , Peter Zijlstra , Joel Schopp , Benjamin Herrenschmidt , Paul Mackerras , Ingo Molnar , Vaidyanathan Srinivasan , Dipankar Sarma , Balbir Singh , Gautham R Shenoy , Shaohua Li , Venkatesh Pallipadi , Arun Bharadwaj Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org Subject: Re: [v6 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER. Message-ID: <20090924051238.GA5963@linux.vnet.ibm.com> Reply-To: arun@linux.vnet.ibm.com References: <20090922112526.GA7788@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20090922112526.GA7788@linux.vnet.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Arun R Bharadwaj [2009-09-22 16:55:27]: Hi Len, (or other acpi folks), I had a question regarding ACPI-cpuidle interaction in the current implementation. Currently, every cpu (i.e. acpi_processor) registers to cpuidle as a cpuidle_device. So every cpu has to go through the process of setting up the idle states and then registering as a cpuidle device. What exactly is the reason behind this? Is this really necessary or can we have a system-wide one-time registering to cpuidle by ACPI? I'm currently in the process of enabling cpuidle for POWER systems and find that having a system-wide registering mechanism to be a cleaner design. --arun