From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753457AbaIKJET (ORCPT ); Thu, 11 Sep 2014 05:04:19 -0400 Received: from mga14.intel.com ([192.55.52.115]:30409 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752964AbaIKIyI (ORCPT ); Thu, 11 Sep 2014 04:54:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,504,1406617200"; d="scan'208";a="589733169" From: Qiaowei Ren To: "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , Dave Hansen Cc: x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Qiaowei Ren Subject: [PATCH v8 03/10] x86, mpx: add macro cpu_has_mpx Date: Thu, 11 Sep 2014 16:46:43 +0800 Message-Id: <1410425210-24789-4-git-send-email-qiaowei.ren@intel.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1410425210-24789-1-git-send-email-qiaowei.ren@intel.com> References: <1410425210-24789-1-git-send-email-qiaowei.ren@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to do performance optimization, this patch adds macro cpu_has_mpx which will directly return 0 when MPX is not supported by kernel. Community gave a lot of comments on this macro cpu_has_mpx in previous version. Dave will introduce a patchset about disabled features to fix it later. In this code: if (cpu_has_mpx) do_some_mpx_thing(); The patch series from Dave will introduce a new macro cpu_feature_enabled() (if merged after this patchset) to replace the cpu_has_mpx. if (cpu_feature_enabled(X86_FEATURE_MPX)) do_some_mpx_thing(); Signed-off-by: Qiaowei Ren --- arch/x86/include/asm/cpufeature.h | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index bb9b258..82ec7ed 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -353,6 +353,12 @@ extern const char * const x86_bug_flags[NBUGINTS*32]; #define cpu_has_eager_fpu boot_cpu_has(X86_FEATURE_EAGER_FPU) #define cpu_has_topoext boot_cpu_has(X86_FEATURE_TOPOEXT) +#ifdef CONFIG_X86_INTEL_MPX +#define cpu_has_mpx boot_cpu_has(X86_FEATURE_MPX) +#else +#define cpu_has_mpx 0 +#endif /* CONFIG_X86_INTEL_MPX */ + #ifdef CONFIG_X86_64 #undef cpu_has_vme -- 1.7.1