Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751985Ab2BUCcg (ORCPT ); Mon, 20 Feb 2012 21:32:36 -0500 Received: from terminus.zytor.com ([198.137.202.10]:39740 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751501Ab2BUCcf (ORCPT ); Mon, 20 Feb 2012 21:32:35 -0500 Message-ID: <4F430230.1010505@zytor.com> Date: Mon, 20 Feb 2012 18:32:16 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0) Gecko/20120131 Thunderbird/10.0 MIME-Version: 1.0 To: Linus Torvalds CC: Josh Boyer , Jongman Heo , Thomas Gleixner , Ingo Molnar , x86@kernel.org, Linux Kernel Mailing List Subject: Re: [PATCH v2 3/3] i387: support lazy restore of FPU state References: In-Reply-To: X-Enigmail-Version: 1.3.5 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1120 Lines: 32 On 02/20/2012 06:18 PM, Linus Torvalds wrote: > >> Although I do wonder if we should just make kernel_fpu_begin() be a >> real function instead of inlining it. I'm not sure it makes sense to >> inline that thing, and it might be better to export that one instead. > > I do think that would be better in the long run, but for now here's an > updated "trivial" patch to fix it. > There is actually another very good reason for out-of-lining kernel_fpu_begin/_end: it will act as a compiler barrier i we ever do compiler-generated SSE or AVX code, which we may very well want to do. In fact, there may even be good reason for something like: kernel_fpu_use(void (*func)(void *), void *arg); ... where the FPU-using stuff is actively embedded in the call. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/