Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752075Ab0H3Fop (ORCPT ); Mon, 30 Aug 2010 01:44:45 -0400 Received: from freeflow.nu ([178.79.134.28]:49307 "EHLO freeflow.nu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750760Ab0H3Fop (ORCPT ); Mon, 30 Aug 2010 01:44:45 -0400 Message-ID: <4C7B454A.7050101@kernel.org> Date: Mon, 30 Aug 2010 08:44:42 +0300 From: Pekka Enberg User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.8) Gecko/20100802 Thunderbird/3.1.2 MIME-Version: 1.0 To: Brian Gerst CC: hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 10/11] x86: Remove unnecessary ifdefs from i387 code. References: <1283011478-27237-1-git-send-email-brgerst@gmail.com> <1283011478-27237-11-git-send-email-brgerst@gmail.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1219 Lines: 29 Hi Brian, On 8/30/10 2:38 AM, Brian Gerst wrote: > On Sun, Aug 29, 2010 at 3:00 PM, Pekka Enberg wrote: >> On Sat, Aug 28, 2010 at 7:04 PM, Brian Gerst wrote: >>> Remove ifdefs for code that the compiler can optimize away on 64-bit. >>> >>> Signed-off-by: Brian Gerst >>> @@ -74,10 +74,8 @@ static void __cpuinit init_thread_xstate(void) >>> >>> if (cpu_has_fxsr) >>> xstate_size = sizeof(struct i387_fxsave_struct); >>> -#ifdef CONFIG_X86_32 >>> else >>> xstate_size = sizeof(struct i387_fsave_struct); >>> -#endif >>> } >> I guess this is OK but keep in mind that cpu_has_fsxr is _not_ >> optimized by the compiler on 64-bit so the change probably increases >> kernel text by few bytes. > FXSR is a required feature on 64-bit, therefore cpu_has_fxsr is always true. Yes, I realize that but it will still read boot_cpu_data at runtime, no? Pekka -- 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/