From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F296FC00A89 for ; Mon, 2 Nov 2020 19:54:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77C7822268 for ; Mon, 2 Nov 2020 19:54:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604346874; bh=XSKqsn3P2/pXv/MCbKfRw59VxuoIrUSEkA+QHvC1urI=; h=From:To:Cc:Subject:Date:List-ID:From; b=mPdGwwibbm4DtBmBuxjYBUvJo6DzvtYuqEF5gQ5ySwdYFhguQsZNBye+LYd67rFx5 uO6OmKirg5groKe8m2nxQi+JqvsF222i+d2N9ACWUImmpdtxz10QH+9bM7KxFEr4Z9 rlW9MbeEAQzfIQIDCTkoh2uzVlJ55EO5tNIOrZ8U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727150AbgKBTyd (ORCPT ); Mon, 2 Nov 2020 14:54:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:39330 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727145AbgKBTyF (ORCPT ); Mon, 2 Nov 2020 14:54:05 -0500 Received: from localhost (c-67-180-165-146.hsd1.ca.comcast.net [67.180.165.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7A9052225E; Mon, 2 Nov 2020 19:54:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604346844; bh=XSKqsn3P2/pXv/MCbKfRw59VxuoIrUSEkA+QHvC1urI=; h=From:To:Cc:Subject:Date:From; b=C65vDUFHBMWfeWycrASThmwyc1A4ZuKeBz9o7K1SMK8F6XuZTnJKsdQWUBnmdEscZ Owae24HwhDTm8OvKN08Z+833e1Y+yWXQS6WkXj8PJ5tlPbrv+W6BmuE67o6QqWuS6c 1OAO1fyJQwLeJcxMFr/6shNzfDPfnElEC/ij8E+o= From: Andy Lutomirski To: x86@kernel.org Cc: LKML , Andy Lutomirski Subject: [PATCH] selftests/x86: Use __builtin_ia32_read/writeeflags Date: Mon, 2 Nov 2020 11:54:02 -0800 Message-Id: X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The asm to read and write EFLAGS from userspace is horrible. The compiler builtins are now available on all supported compilers, so use them instead. (The compiler builtins are also unnecessarily ugly, but that's a more manageable level of ugliness.) Signed-off-by: Andy Lutomirski --- tools/testing/selftests/x86/helpers.h | 24 ++++-------------------- 1 file changed, 4 insertions(+), 20 deletions(-) diff --git a/tools/testing/selftests/x86/helpers.h b/tools/testing/selftests/x86/helpers.h index f5ff2a2615df..4ef42c4559a9 100644 --- a/tools/testing/selftests/x86/helpers.h +++ b/tools/testing/selftests/x86/helpers.h @@ -6,36 +6,20 @@ static inline unsigned long get_eflags(void) { - unsigned long eflags; - - asm volatile ( #ifdef __x86_64__ - "subq $128, %%rsp\n\t" - "pushfq\n\t" - "popq %0\n\t" - "addq $128, %%rsp" + return __builtin_ia32_readeflags_u64(); #else - "pushfl\n\t" - "popl %0" + return __builtin_ia32_readeflags_u32(); #endif - : "=r" (eflags) :: "memory"); - - return eflags; } static inline void set_eflags(unsigned long eflags) { - asm volatile ( #ifdef __x86_64__ - "subq $128, %%rsp\n\t" - "pushq %0\n\t" - "popfq\n\t" - "addq $128, %%rsp" + __builtin_ia32_writeeflags_u64(eflags); #else - "pushl %0\n\t" - "popfl" + __builtin_ia32_writeeflags_u32(eflags); #endif - :: "r" (eflags) : "flags", "memory"); } #endif /* __SELFTESTS_X86_HELPERS_H */ -- 2.28.0