From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753130AbcFCVU0 (ORCPT ); Fri, 3 Jun 2016 17:20:26 -0400 Received: from mail-by2on0107.outbound.protection.outlook.com ([207.46.100.107]:46865 "EHLO na01-by2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752084AbcFCVUZ (ORCPT ); Fri, 3 Jun 2016 17:20:25 -0400 Authentication-Results: linux.vnet.ibm.com; dkim=none (message not signed) header.d=none;linux.vnet.ibm.com; dmarc=none action=none header.from=hpe.com; Message-ID: <5751F48A.6090508@hpe.com> Date: Fri, 3 Jun 2016 17:20:10 -0400 From: Waiman Long User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130109 Thunderbird/10.0.12 MIME-Version: 1.0 To: Pan Xinhui CC: , , Subject: Re: [PATCH] locking/qspinlock: Use this_cpu_ptr instead of this_cpu_dec References: <1464947330-3568-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> In-Reply-To: <1464947330-3568-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> Content-Type: text/plain; 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> + this_cpu_ptr(&mcs_nodes[0])->count--; > } > EXPORT_SYMBOL(queued_spin_lock_slowpath); > Is this going to generate better code for PPC? For x86, I think it will cause more instruction to be issued. Cheers, Longman