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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28BA1C433EF for ; Fri, 6 May 2022 09:21:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1390437AbiEFJYu (ORCPT ); Fri, 6 May 2022 05:24:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241918AbiEFJYm (ORCPT ); Fri, 6 May 2022 05:24:42 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06F6F63519; Fri, 6 May 2022 02:20:35 -0700 (PDT) Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 2468H6Zb040135; Fri, 6 May 2022 09:20:35 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=XEeW7SkkfqHkJZkTeoDfscRJfoW2dvyrjFvMW1PWUmw=; b=eSkRsj2GjIOxuasMbotgPEITze1e9iqPvbJ1KJIfA7eBVxQJ2euchTlmj/P76AxzfzOM c9VQ6fTFkp3eFghlmdt3jG1c8eogCAfFcF+vR+U9JvqOc+bz6Wm0K1ndfvIxiK6IXwbh 5s6WfFqj/sNy2mA3bJPGzVW3VUolGfUqjNh6lQGDU2bppQk4AhBdru0VjpyaNJyt9HJQ s2uvlXK3b/oc/RChNu7UZJ4LCU3/cH/upSru5puGsncGnMwlwQHpHmpXskflEt02dGWc owCuXKreKwKpTavra/vQ8z5QgUG37djCCEjJUEFvR2+EQg0kb8sXU6+2UXVp8HZ779ym Mw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3fw0179at7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 06 May 2022 09:20:35 +0000 Received: from m0187473.ppops.net (m0187473.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 2469DRlc001898; Fri, 6 May 2022 09:20:34 GMT Received: from ppma03ams.nl.ibm.com (62.31.33a9.ip4.static.sl-reverse.com [169.51.49.98]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3fw0179asj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 06 May 2022 09:20:34 +0000 Received: from pps.filterd (ppma03ams.nl.ibm.com [127.0.0.1]) by ppma03ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 2469DkWS021130; Fri, 6 May 2022 09:20:32 GMT Received: from b06avi18878370.portsmouth.uk.ibm.com (b06avi18878370.portsmouth.uk.ibm.com [9.149.26.194]) by ppma03ams.nl.ibm.com with ESMTP id 3ftp7fw874-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 06 May 2022 09:20:32 +0000 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 2469KMhV21561646 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 6 May 2022 09:20:22 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4856711C04C; Fri, 6 May 2022 09:20:29 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 879B311C04A; Fri, 6 May 2022 09:20:28 +0000 (GMT) Received: from li-c6ac47cc-293c-11b2-a85c-d421c8e4747b.ibm.com.com (unknown [9.171.62.79]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 6 May 2022 09:20:28 +0000 (GMT) From: Pierre Morel To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, borntraeger@de.ibm.com, frankja@linux.ibm.com, cohuck@redhat.com, david@redhat.com, thuth@redhat.com, imbrenda@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, pmorel@linux.ibm.com, wintera@linux.ibm.com, seiden@linux.ibm.com, nrb@linux.ibm.com Subject: [PATCH v9 0/3] s390x: KVM: CPU Topology Date: Fri, 6 May 2022 11:24:00 +0200 Message-Id: <20220506092403.47406-1-pmorel@linux.ibm.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: RvDBeqAdxUJi9e8CM5nI5Bk_2XxsrhYA X-Proofpoint-ORIG-GUID: tYw0nMt7WSgjZGyyOsmHyvKuim5yjyF1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-05-06_03,2022-05-05_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 phishscore=0 clxscore=1011 priorityscore=1501 mlxscore=0 mlxlogscore=999 bulkscore=0 spamscore=0 suspectscore=0 malwarescore=0 impostorscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2205060049 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, This new spin adds bug correction and simplification of ipte_lock to the series for the implementation of interpretation for the PTF instruction and the handling of the STSI instruction. The series provides: 1- interception of the STSI instruction forwarding the CPU topology 2- interpretation of the PTF instruction 3- a KVM capability for the userland hypervisor to ask KVM to setup PTF interpretation. 0- Foreword The S390 CPU topology is reported using two instructions: - PTF, to get information if the CPU topology did change since last PTF instruction or a subsystem reset. - STSI, to get the topology information, consisting of the topology of the CPU inside the sockets, of the sockets inside the books etc. The PTF(2) instruction report a change if the STSI(15.1.2) instruction will report a difference with the last STSI(15.1.2) instruction*. With the SIE interpretation, the PTF(2) instruction will report a change to the guest if the host sets the SCA.MTCR bit. *The STSI(15.1.2) instruction reports: - The cores address within a socket - The polarization of the cores - The CPU type of the cores - If the cores are dedicated or not We decided to implement the CPU topology for S390 in several steps: - first we report CPU hotplug - modification of the CPU mask inside sockets In future development we will provide: - handling of shared CPUs - reporting of the CPU Type - reporting of the polarization 1- Interception of STSI To provide Topology information to the guest through the STSI instruction, we forward STSI with Function Code 15 to the userland hypervisor which will take care to provide the right information to the guest. To let the guest use both the PTF instruction to check if a topology change occurred and sthe STSI_15.x.x instruction we add a new KVM capability to enable the topology facility. 2- Interpretation of PTF with FC(2) The PTF instruction will report a topology change if there is any change with a previous STSI(15.1.2) SYSIB. Changes inside a STSI(15.1.2) SYSIB occur if CPU bits are set or clear inside the CPU Topology List Entry CPU mask field, which happens with changes in CPU polarization, dedication, CPU types and adding or removing CPUs in a socket. The reporting to the guest is done using the Multiprocessor Topology-Change-Report (MTCR) bit of the utility entry of the guest's SCA which will be cleared during the interpretation of PTF. To check if the topology has been modified we use a new field of the arch vCPU prev_cpu, to save the previous real CPU ID at the end of a schedule and verify on next schedule that the CPU used is in the same socket, this field is initialized to -1 on vCPU creation. Regards, Pierre Pierre Morel (3): s390x: KVM: ipte lock for SCA access should be contained in KVM s390x: KVM: guest support for topology function s390x: KVM: resetting the Topology-Change-Report Documentation/virt/kvm/api.rst | 16 ++++ arch/s390/include/asm/kvm_host.h | 12 ++- arch/s390/include/uapi/asm/kvm.h | 5 ++ arch/s390/kvm/gaccess.c | 96 +++++++++++------------ arch/s390/kvm/gaccess.h | 6 +- arch/s390/kvm/kvm-s390.c | 128 ++++++++++++++++++++++++++++++- arch/s390/kvm/kvm-s390.h | 25 ++++++ arch/s390/kvm/priv.c | 20 +++-- arch/s390/kvm/vsie.c | 3 + include/uapi/linux/kvm.h | 1 + 10 files changed, 250 insertions(+), 62 deletions(-) -- 2.27.0 Changelog: from v8 to v9 - bug correction in kvm_s390_topology_changed (Heiko) - simplification for ipte_lock/unlock to use kvm as arg instead of vcpu and test on sclp.has_siif instead of the SIE ECA_SII. (David) - use of a single value for reporting if the topology changed instead of a structure (David) from v7 to v8 - implement reset handling (Janosch) - change the way to check if the topology changed (Nico, Heiko) from v6 to v7 - rebase from v5 to v6 - make the subject more accurate (Claudio) - Change the kvm_s390_set_mtcr() function to have vcpu in the name (Janosch) - Replace the checks on ECB_PTF wit the check of facility 11 (Janosch) - modify kvm_arch_vcpu_load, move the check in a function in the header file (Janosh) - No magical number replace the "new cpu value" of -1 with a define (Janosch) - Make the checks for STSI validity clearer (Janosch) from v4 tp v5 - modify the way KVM_CAP is tested to be OK with vsie (David) from v3 to v4 - squatch both patches (David) - Added Documentation (David) - Modified the detection for new vCPUs (Pierre) from v2 to v3 - use PTF interpretation (Christian) - optimize arch_update_cpu_topology using PTF (Pierre) from v1 to v2: - Add a KVM capability to let QEMU know we support PTF and STSI 15 (David) - check KVM facility 11 before accepting STSI fc 15 (David) - handle all we can in userland (David) - add tracing to STSI fc 15 (Connie)