From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935971AbXJQCaK (ORCPT ); Tue, 16 Oct 2007 22:30:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758607AbXJQC35 (ORCPT ); Tue, 16 Oct 2007 22:29:57 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:37192 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754103AbXJQC34 (ORCPT ); Tue, 16 Oct 2007 22:29:56 -0400 Date: Tue, 16 Oct 2007 19:23:38 -0700 (PDT) From: Linus Torvalds To: Dipankar Sarma cc: Gautham R Shenoy , Andrew Morton , linux-kernel@vger.kernel.org, Srivatsa Vaddagiri , Rusty Russel , Oleg Nesterov , Ingo Molnar , Paul E McKenney Subject: Re: [RFC PATCH 0/4] Refcount Based Cpu-Hotplug Revisit. In-Reply-To: <20071017021112.GA15895@in.ibm.com> Message-ID: References: <20071016103308.GA9907@in.ibm.com> <20071017021112.GA15895@in.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 17 Oct 2007, Dipankar Sarma wrote: > > Unless I am reading the patch wrongly, it seems cpu_hotplug_begin() is called > while holding the cpu_add_remove_lock mutex. So, another CPU cannot come in > and do the same until _cpu_down() is over. Ahh, in that case I take back that objection, although maybe a comment about the required nesting within the other mutex is in order? Or maybe it's there and I just missed it (blush). Linus