From patchwork Fri Apr 1 07:14:34 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 8721331 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 7AFF59F38C for ; Fri, 1 Apr 2016 07:18:08 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 034BF203B6 for ; Fri, 1 Apr 2016 07:18:03 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2834D203AE for ; Fri, 1 Apr 2016 07:18:02 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1altJ4-0007nU-8F; Fri, 01 Apr 2016 07:15:46 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1altJ3-0007mQ-9V for xen-devel@lists.xenproject.org; Fri, 01 Apr 2016 07:15:45 +0000 Received: from [85.158.137.68] by server-8.bemta-3.messagelabs.com id 42/34-04050-0202EF65; Fri, 01 Apr 2016 07:15:44 +0000 X-Env-Sender: jgross@suse.com X-Msg-Ref: server-10.tower-31.messagelabs.com!1459494943!32410611!1 X-Originating-IP: [195.135.220.15] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 8.11; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25711 invoked from network); 1 Apr 2016 07:15:43 -0000 Received: from mx2.suse.de (HELO mx2.suse.de) (195.135.220.15) by server-10.tower-31.messagelabs.com with DHE-RSA-CAMELLIA256-SHA encrypted SMTP; 1 Apr 2016 07:15:43 -0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 74FB2AC64; Fri, 1 Apr 2016 07:14:39 +0000 (UTC) From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Date: Fri, 1 Apr 2016 09:14:34 +0200 Message-Id: <1459494874-12194-7-git-send-email-jgross@suse.com> X-Mailer: git-send-email 2.6.2 In-Reply-To: <1459494874-12194-1-git-send-email-jgross@suse.com> References: <1459494874-12194-1-git-send-email-jgross@suse.com> Cc: Juergen Gross , jeremy@goop.org, jdelvare@suse.com, peterz@infradead.org, hpa@zytor.com, akataria@vmware.com, x86@kernel.org, rusty@rustcorp.com.au, virtualization@lists.linux-foundation.org, chrisw@sous-sol.org, mingo@redhat.com, david.vrabel@citrix.com, Douglas_Warzecha@dell.com, pali.rohar@gmail.com, boris.ostrovsky@oracle.com, tglx@linutronix.de, linux@roeck-us.net Subject: [Xen-devel] [PATCH v3 6/6] xen: add xen_pin_vcpu() to support calling functions on a dedicated pcpu X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 Some hardware models (e.g. Dell Studio 1555 laptops) require calls to the firmware to be issued on cpu 0 only. As Dom0 might have to use these calls, add xen_pin_vcpu() to achieve this functionality. In case either the domain doesn't have the privilege to make the related hypercall or the hypervisor isn't supporting it, issue a warning once and disable further pinning attempts. Signed-off-by: Juergen Gross --- arch/x86/xen/enlighten.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 880862c..7907bcf8 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1885,6 +1885,45 @@ static void xen_set_cpu_features(struct cpuinfo_x86 *c) } } +static void xen_pin_vcpu(int cpu) +{ + static bool disable_pinning; + struct sched_pin_override pin_override; + int ret; + + if (disable_pinning) + return; + + pin_override.pcpu = cpu; + ret = HYPERVISOR_sched_op(SCHEDOP_pin_override, &pin_override); + if (cpu < 0) + return; + + switch (ret) { + case -ENOSYS: + pr_warn("The kernel tried to call a function on physical cpu %d, but Xen isn't\n" + "supporting this. In case of problems you might consider vcpu pinning.\n", + cpu); + disable_pinning = true; + break; + case -EPERM: + WARN(1, "Trying to pin vcpu without having privilege to do so\n"); + disable_pinning = true; + break; + case -EINVAL: + case -EBUSY: + pr_warn("The kernel tried to call a function on physical cpu %d, but this cpu\n" + "seems not to be available. Please check your Xen cpu configuration.\n", + cpu); + break; + case 0: + break; + default: + WARN(1, "rc %d while trying to pin vcpu\n", ret); + disable_pinning = true; + } +} + const struct hypervisor_x86 x86_hyper_xen = { .name = "Xen", .detect = xen_platform, @@ -1893,6 +1932,7 @@ const struct hypervisor_x86 x86_hyper_xen = { #endif .x2apic_available = xen_x2apic_para_available, .set_cpu_features = xen_set_cpu_features, + .pin_vcpu = xen_pin_vcpu, }; EXPORT_SYMBOL(x86_hyper_xen);