From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 29 May 2012 08:53:15 +0200 (CEST) Received: from mail-vb0-f49.google.com ([209.85.212.49]:45978 "EHLO mail-vb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S1903544Ab2E2GxI (ORCPT ); Tue, 29 May 2012 08:53:08 +0200 Received: by vbbfo1 with SMTP id fo1so2695292vbb.36 for ; Mon, 28 May 2012 23:53:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:reply-to:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=ioR/RRJR6ly/G5UOpXKQQXnLe/VttkoAA+qBXXfV9KU=; b=lG8W8udH+AwGM6uaXrg1KFHsDZ6PxPsOOG877H/wB4Kdf/Kwhbv9akCaAz6/YWT6SA mxkGuFUr919KJD/JwGzHi6tCdZFKyabVSl3K2nvNzI6FiYwxeunMgciFL+AmkDIZ092U /3vcF3Qpod0HdU/8JVjdKjlJIPwLH6WtJV0aUYWyhldt3B/4I4iCipBJTDUp17lcySzZ saD82HuIiPoQt4wX841jRV6AICrNaOStY6N4Gav3CtSZsX5rDUKyIvJJvXT87zETF+vC bjvdYvE/u+AYShOswIFO1KprKuzrQLEKqteihbdLNO3FCbv3yg5IvIjX/XiGoU4QAofN MwQw== Received: by 10.220.214.8 with SMTP id gy8mr11607686vcb.45.1338274382107; Mon, 28 May 2012 23:53:02 -0700 (PDT) Received: from localhost ([61.148.56.138]) by mx.google.com with ESMTPS id bj6sm22888431vdc.12.2012.05.28.23.52.53 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 28 May 2012 23:52:59 -0700 (PDT) Date: Tue, 29 May 2012 14:52:48 +0800 From: Yong Zhang To: "Srivatsa S. Bhat" Cc: linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, ralf@linux-mips.org, sshtylyov@mvista.com, david.daney@cavium.com, Nikunj A Dadhania , "Paul E. McKenney" , axboe@kernel.dk, jeremy.fitzhardinge@citrix.com, Ingo Molnar , Thomas Gleixner Subject: Re: [PATCH 6/8] MIPS: call set_cpu_online() on the uping cpu with irq disabled Message-ID: <20120529065248.GA2597@zhy> Reply-To: Yong Zhang References: <1337580008-7280-1-git-send-email-yong.zhang0@gmail.com> <1337580008-7280-7-git-send-email-yong.zhang0@gmail.com> <4FBA1B54.3@linux.vnet.ibm.com> <20120522062126.GB12098@zhy> <4FC369E3.1030901@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <4FC369E3.1030901@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-archive-position: 33473 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: yong.zhang0@gmail.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips Return-Path: On Mon, May 28, 2012 at 05:34:51PM +0530, Srivatsa S. Bhat wrote: > No, I think you are right. Sorry for the delay in replying. > It indeed looks like we need not use ipi_call_lock/unlock() in CPU bringup > code.. > > However, it does make me wonder about this: > commit 3d4422332 introduced the generic ipi helpers, and reduced the scope > of call_function.lock and also added the check in > generic_smp_call_function_interrupt() to proceed only if the cpu is present > in data->cpumask. > > Then, commit 3b16cf8748 converted x86 to the generic ipi helpers, but while > doing that, it explicitly retained ipi_call_lock/unlock(), which is kind of > surprising.. I guess it was a mistake rather than intentional. Agree. I think it's a mistake(or leftover) too :) Anyway, let me cook a patch to throw a stone to clear the road. Thanks, Yong