From patchwork Wed Oct 28 01:39:57 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 7506101 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 390EBBEEA4 for ; Wed, 28 Oct 2015 01:40:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4FDF4205E1 for ; Wed, 28 Oct 2015 01:40:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 58BEA205DD for ; Wed, 28 Oct 2015 01:40:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755142AbbJ1Bkl (ORCPT ); Tue, 27 Oct 2015 21:40:41 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:34252 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755055AbbJ1BkT (ORCPT ); Tue, 27 Oct 2015 21:40:19 -0400 Received: by wikq8 with SMTP id q8so235449906wik.1; Tue, 27 Oct 2015 18:40:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=I9XotUVEVA8r1shibAsWF7sXEpD18oUYq1quHlirqrQ=; b=oga+w82J5MIvqBxXMa8KzXu/LEjvKQ+W/RwaAOI5PtB1K3RuevsE8SrggRsohsgX7A 92HAHcF86pEkRXBRI86peONSUNIKGg5zGhaMm0AGNQN5R9aPzOXTo/tZ+QFRuv45JdkZ KaFu/b+f1pVEeKTGGLXKpb1M2QMv4M0p/yRpQcfVhPkZUoUBJ2ysW154ezLseqNiH/Xu hLOC8kNvGuk9njaZwJo2tFEqEKajlb7Gf71Lkb3Tj19eo/bb+HKDsvUqhOGdYvi+Yb6n WKaCbA7u3mH5ku+kNHr975Vfd6jCnzzIxO+3OaXPZua1oaPSS4DPMvlrfeI/rOcyXuxx 2BWw== X-Received: by 10.180.205.145 with SMTP id lg17mr184744wic.67.1445996418112; Tue, 27 Oct 2015 18:40:18 -0700 (PDT) Received: from donizetti.redhat.com ([58.123.138.250]) by smtp.gmail.com with ESMTPSA id pi5sm19666087wic.3.2015.10.27.18.40.15 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 27 Oct 2015 18:40:17 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Andy Lutomirski , Frederic Weisbecker , Rik van Riel , Paul McKenney Subject: [PATCH 3/3] x86: context_tracking: avoid irq_save/irq_restore on kernel entry and exit Date: Wed, 28 Oct 2015 02:39:57 +0100 Message-Id: <1445996397-32703-4-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1445996397-32703-1-git-send-email-pbonzini@redhat.com> References: <1445996397-32703-1-git-send-email-pbonzini@redhat.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP x86 always calls user_enter and user_exit with interrupt disabled. Therefore, it is not necessary to check for exceptions, nor to save/restore the IRQ state, when context tracking functions are called by guest_enter and guest_exit. Use the previously introduced __context_tracking_entry and __context_tracking_exit. Cc: Andy Lutomirski Cc: Frederic Weisbecker Cc: Rik van Riel Cc: Paul McKenney Signed-off-by: Paolo Bonzini --- arch/x86/entry/common.c | 4 ++-- include/linux/context_tracking.h | 42 ++++++++++++++++++++++++++-------------- 2 files changed, 30 insertions(+), 16 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 80dcc9261ca3..ba707c6da818 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -33,7 +33,7 @@ __visible void enter_from_user_mode(void) { CT_WARN_ON(ct_state() != CONTEXT_USER); - user_exit(); + __user_exit(); } #endif @@ -262,7 +262,7 @@ __visible void prepare_exit_to_usermode(struct pt_regs *regs) local_irq_disable(); } - user_enter(); + __user_enter(); } /* diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index 68b575afe5f5..d36a5c8085b7 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -19,18 +19,6 @@ extern void context_tracking_exit(enum ctx_state state); extern void context_tracking_user_enter(void); extern void context_tracking_user_exit(void); -static inline void user_enter(void) -{ - if (context_tracking_is_enabled()) - context_tracking_enter(CONTEXT_USER); - -} -static inline void user_exit(void) -{ - if (context_tracking_is_enabled()) - context_tracking_exit(CONTEXT_USER); -} - static inline enum ctx_state exception_enter(void) { enum ctx_state prev_ctx; @@ -67,13 +55,39 @@ static inline enum ctx_state ct_state(void) this_cpu_read(context_tracking.state) : CONTEXT_DISABLED; } #else -static inline void user_enter(void) { } -static inline void user_exit(void) { } +static inline void __context_tracking_enter(enum ctx_state state) { } +static inline void __context_tracking_exit(enum ctx_state state) { } +static inline void context_tracking_enter(enum ctx_state state) { } +static inline void context_tracking_exit(enum ctx_state state) { } static inline enum ctx_state exception_enter(void) { return 0; } static inline void exception_exit(enum ctx_state prev_ctx) { } static inline enum ctx_state ct_state(void) { return CONTEXT_DISABLED; } #endif /* !CONFIG_CONTEXT_TRACKING */ +static inline void __user_enter(void) +{ + if (context_tracking_is_enabled()) + __context_tracking_enter(CONTEXT_USER); + +} +static inline void __user_exit(void) +{ + if (context_tracking_is_enabled()) + __context_tracking_exit(CONTEXT_USER); +} + +static inline void user_enter(void) +{ + if (context_tracking_is_enabled()) + context_tracking_enter(CONTEXT_USER); + +} +static inline void user_exit(void) +{ + if (context_tracking_is_enabled()) + context_tracking_exit(CONTEXT_USER); +} + #define CT_WARN_ON(cond) WARN_ON(context_tracking_is_enabled() && (cond)) #ifdef CONFIG_CONTEXT_TRACKING_FORCE