From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161287AbaKNQUV (ORCPT ); Fri, 14 Nov 2014 11:20:21 -0500 Received: from mout.kundenserver.de ([212.227.17.24]:54184 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161247AbaKNQUT (ORCPT ); Fri, 14 Nov 2014 11:20:19 -0500 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Cc: Andre Przywara , will.deacon@arm.com, catalin.marinas@arm.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/6] arm64: alternatives runtime patching Date: Fri, 14 Nov 2014 17:20:10 +0100 Message-ID: <2041011.PXfvHs4Xp7@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1415980452-20366-1-git-send-email-andre.przywara@arm.com> References: <1415980452-20366-1-git-send-email-andre.przywara@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V02:K0:hqFlDF9kxop4/kzhLVg2a2/jB55yrZNO1IcrK3yZFRS QZnJzvc6XsMfADfchI7jNzcDaarZB/Xn1ESy+ZkHwLqz5x0GUD W6c96Qg9gStRkA2MJmUqLGB+zF9XJrDJN+2nNfgFtjugpVpvB+ Uc/bRVg72YpZd9mroXA5MHBIxhEqlMe6Sr9bG2dj5AwgR+EHuA GNEGLwlYBUXtCIb6j8uAnK76mQjuO/yBqaaiwmUzU17LMN+IzY +uLYNMDeaxKAzT6NSbRY9xLtIw7KrLuSbNys0yHsjsSC3JnXja lwe7INlQaM7ISd0O9WJnXcz+GiuVM9RskDYHRX6KVxOtOyQfeN IDR2ADOVqLINk+GfVrUQ= X-UI-Out-Filterresults: notjunk:1; Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday 14 November 2014 15:54:06 Andre Przywara wrote: > This series introduces alternatives runtime patching to arm64. > This allows to patch assembly instruction at runtime to either > fix hardware bugs or optimize for certain hardware features. Look > at patch 5/6 for an example on how to use this. > Does it provide a measurable performance benefit? The implementation seems ok, but we should only add the complexity for things that actually need it and can't be handled just as well with a run-time conditional. Arnd