Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752819AbaJTGtm (ORCPT ); Mon, 20 Oct 2014 02:49:42 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:48471 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752726AbaJTGtj (ORCPT ); Mon, 20 Oct 2014 02:49:39 -0400 Date: Mon, 20 Oct 2014 14:48:26 +0800 From: Greg KH To: Neil Zhang Cc: "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] drivers: base: update cpu offline info when do hotplug Message-ID: <20141020064826.GA4064@kroah.com> References: <1413775748-22478-1-git-send-email-zhangwm@marvell.com> <20141020044340.GA9589@kroah.com> <9034CBD80F070943B59700D7F8149ED9024EB81CAF@SC-VEXCH4.marvell.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9034CBD80F070943B59700D7F8149ED9024EB81CAF@SC-VEXCH4.marvell.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Oct 19, 2014 at 11:39:23PM -0700, Neil Zhang wrote: >> How much noise is this going to cause on a big/little system that >> constantly hot unplug/plugs processors all of the time? > > Can you explain more what kind of noise will be introduced on a big/little system? Have you tested this on such a machine? > As I know IKS on arm will use cpu_suspend way to power down a core. Are you sure that it also doesn't use that same functionality to drop a processor to save power? Why do you need/want this notification? What are you going to do with this information that you don't already have? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/