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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 67474C2BB1D for ; Fri, 17 Apr 2020 20:48:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AA6520656 for ; Fri, 17 Apr 2020 20:48:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726396AbgDQUsj (ORCPT ); Fri, 17 Apr 2020 16:48:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725915AbgDQUsj (ORCPT ); Fri, 17 Apr 2020 16:48:39 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D389AC061A0C for ; Fri, 17 Apr 2020 13:48:38 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jPXuc-0006z8-UC; Fri, 17 Apr 2020 22:48:35 +0200 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id 6090C100C47; Fri, 17 Apr 2020 22:48:34 +0200 (CEST) From: Thomas Gleixner To: "Luck\, Tony" Cc: Ingo Molnar , Fenghua Yu , Borislav Petkov , H Peter Anvin , Ashok Raj , Ravi V Shankar , Sean Christopherson , Andy Lutomirski , linux-kernel@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH 2/3] x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural In-Reply-To: <20200417195601.GA22640@agluck-desk2.amr.corp.intel.com> References: <20200416205754.21177-1-tony.luck@intel.com> <20200416205754.21177-3-tony.luck@intel.com> <878siumnrf.fsf@nanos.tec.linutronix.de> <20200417170607.GA18267@agluck-desk2.amr.corp.intel.com> <87ftd1zzau.fsf@nanos.tec.linutronix.de> <20200417195601.GA22640@agluck-desk2.amr.corp.intel.com> Date: Fri, 17 Apr 2020 22:48:34 +0200 Message-ID: <877dydzvml.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "Luck, Tony" writes: > On Fri, Apr 17, 2020 at 09:29:13PM +0200, Thomas Gleixner wrote: >> "Luck, Tony" writes: >> > On Fri, Apr 17, 2020 at 12:04:36PM +0200, Thomas Gleixner wrote: >> > + if (!m->driver_data) >> > + goto setup; >> > + if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES)) >> > + return; >> > + rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps); >> > + if (!(ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT)) >> > + return; >> > +setup: >> > + split_lock_setup(); >> >> Which looks nicer w/o the goto: >> >> if (m->driver_data) { >> if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES)) >> return; >> rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps); >> if (!(ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT)) >> return; >> } >> >> Hmm? > > Swings and roundabouts ... getting rid of the goto makes for > deeper indentation. But if you really want to get rid of the > goto, then your version is fine with me. > > Do you want me to spin it into v3? Nah. I tweak it myself.