Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756729AbcCXOhB (ORCPT ); Thu, 24 Mar 2016 10:37:01 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:53236 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751989AbcCXOgv (ORCPT ); Thu, 24 Mar 2016 10:36:51 -0400 Subject: Re: [PATCH 1/2] ARM64:VDSO: Improve gettimeofday, don't use udiv To: Andrew Pinski , pinskia@gmail.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <1457898620-1867-1-git-send-email-apinski@cavium.com> <1457898620-1867-2-git-send-email-apinski@cavium.com> Cc: Mark Rutland , Ard Biesheuvel From: Christopher Covington Message-ID: <56F3FB80.50402@codeaurora.org> Date: Thu, 24 Mar 2016 10:36:48 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:43.0) Gecko/20100101 Thunderbird/43.0 MIME-Version: 1.0 In-Reply-To: <1457898620-1867-2-git-send-email-apinski@cavium.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 459 Lines: 15 On 03/13/2016 03:50 PM, Andrew Pinski wrote: > On many cores, udiv with a large value is slow, expand instead > the division out to be what GCC would have generated for the > divide by 1000. This like checking object code into version control. Why not write in C and let GCC perform the generation? Thanks, Cov -- Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project