From patchwork Mon Oct 9 09:32:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nico Boehr X-Patchwork-Id: 13413209 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 003D3E95A91 for ; Mon, 9 Oct 2023 09:33:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345778AbjJIJdR (ORCPT ); Mon, 9 Oct 2023 05:33:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38654 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345801AbjJIJdN (ORCPT ); Mon, 9 Oct 2023 05:33:13 -0400 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3423D6; Mon, 9 Oct 2023 02:33:10 -0700 (PDT) Received: from pps.filterd (m0356516.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3999KKi0010556; Mon, 9 Oct 2023 09:33:10 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=GsAqcjRhOdbINkMlShceUBTTxT/OYQCO13amGLaXTq8=; b=mbYqLPBcAyV+dWJEIebsEE51QHC41LtmbMfbh2QBWy0s6wxQNK9AAg1kCOjHjC8+19M2 FSI4IW3fV7CgsIFnZEtkTgOc7bvk0ElDm8U/mdbmb1LSahkie7zLzcpgwnRV67Nss7QM b4HRfmwpLyjO0S7dCtZN3mxwulYDKSqWDLQETpatRKkH3VmcsoOMeFoCmZDj0OP9zfeu nWUmktyOsezsLHYTzcxHqqzIjltX1aar48Oh1V7vLC9M0Y3Bh8ZdSV7qB91xfomwFAu7 5gJlefed2BNi8Sw+XayFQ1xc1ByZ3ZRxssw5PLUTRGtBZg9+9I3fPiwWALDOB5W0HRJ/ 6Q== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3tmesv0b6j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Oct 2023 09:33:09 +0000 Received: from m0356516.ppops.net (m0356516.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3999LIE5012300; Mon, 9 Oct 2023 09:33:09 GMT Received: from ppma21.wdc07v.mail.ibm.com (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3tmesv0b60-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Oct 2023 09:33:09 +0000 Received: from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1]) by ppma21.wdc07v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 39995WlK026364; Mon, 9 Oct 2023 09:33:08 GMT Received: from smtprelay07.fra02v.mail.ibm.com ([9.218.2.229]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 3tkjnmyyad-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Oct 2023 09:33:08 +0000 Received: from smtpav03.fra02v.mail.ibm.com (smtpav03.fra02v.mail.ibm.com [10.20.54.102]) by smtprelay07.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3999X5bh13107746 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 9 Oct 2023 09:33:05 GMT Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 07D4820040; Mon, 9 Oct 2023 09:33:05 +0000 (GMT) Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C7FF12004D; Mon, 9 Oct 2023 09:33:04 +0000 (GMT) Received: from t35lp63.lnxne.boe (unknown [9.152.108.100]) by smtpav03.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 9 Oct 2023 09:33:04 +0000 (GMT) From: Nico Boehr To: borntraeger@linux.ibm.com, frankja@linux.ibm.com, imbrenda@linux.ibm.com, david@redhat.com Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org Subject: [PATCH v4 1/2] KVM: s390: add stat counter for shadow gmap events Date: Mon, 9 Oct 2023 11:32:52 +0200 Message-ID: <20231009093304.2555344-2-nrb@linux.ibm.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231009093304.2555344-1-nrb@linux.ibm.com> References: <20231009093304.2555344-1-nrb@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: pWoxjNQxLrBI20JSa4CWVFkTxaVWPwyN X-Proofpoint-GUID: 1aFz4AGrsWTq88VeE7S3pSqlxTQ7wcy5 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-10-09_07,2023-10-06_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 suspectscore=0 impostorscore=0 phishscore=0 adultscore=0 priorityscore=1501 spamscore=0 clxscore=1015 mlxlogscore=999 lowpriorityscore=0 bulkscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2310090078 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The shadow gmap tracks memory of nested guests (guest-3). In certain scenarios, the shadow gmap needs to be rebuilt, which is a costly operation since it involves a SIE exit into guest-1 for every entry in the respective shadow level. Add kvm stat counters when new shadow structures are created at various levels. Also add a counter gmap_shadow_create when a completely fresh shadow gmap is created as well as a counter gmap_shadow_reuse when an existing gmap is being reused. Note that when several levels are shadowed at once, counters on all affected levels will be increased. Also note that not all page table levels need to be present and a ASCE can directly point to e.g. a segment table. In this case, a new segment table will always be equivalent to a new shadow gmap and hence will be counted as gmap_shadow_create and not as gmap_shadow_segment. Signed-off-by: Nico Boehr Reviewed-by: David Hildenbrand Reviewed-by: Claudio Imbrenda Reviewed-by: Janosch Frank --- arch/s390/include/asm/kvm_host.h | 7 +++++++ arch/s390/kvm/gaccess.c | 7 +++++++ arch/s390/kvm/kvm-s390.c | 9 ++++++++- arch/s390/kvm/vsie.c | 5 ++++- 4 files changed, 26 insertions(+), 2 deletions(-) diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 427f9528a7b6..67a298b6cf6e 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -777,6 +777,13 @@ struct kvm_vm_stat { u64 inject_service_signal; u64 inject_virtio; u64 aen_forward; + u64 gmap_shadow_create; + u64 gmap_shadow_reuse; + u64 gmap_shadow_r1_entry; + u64 gmap_shadow_r2_entry; + u64 gmap_shadow_r3_entry; + u64 gmap_shadow_sg_entry; + u64 gmap_shadow_pg_entry; }; struct kvm_arch_memory_slot { diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 6d6bc19b37dc..ff8349d17b33 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -1382,6 +1382,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, unsigned long *pgt, int *dat_protection, int *fake) { + struct kvm *kvm; struct gmap *parent; union asce asce; union vaddress vaddr; @@ -1390,6 +1391,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, *fake = 0; *dat_protection = 0; + kvm = sg->private; parent = sg->parent; vaddr.addr = saddr; asce.val = sg->orig_asce; @@ -1450,6 +1452,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, rc = gmap_shadow_r2t(sg, saddr, rfte.val, *fake); if (rc) return rc; + kvm->stat.gmap_shadow_r1_entry++; } fallthrough; case ASCE_TYPE_REGION2: { @@ -1478,6 +1481,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, rc = gmap_shadow_r3t(sg, saddr, rste.val, *fake); if (rc) return rc; + kvm->stat.gmap_shadow_r2_entry++; } fallthrough; case ASCE_TYPE_REGION3: { @@ -1515,6 +1519,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, rc = gmap_shadow_sgt(sg, saddr, rtte.val, *fake); if (rc) return rc; + kvm->stat.gmap_shadow_r3_entry++; } fallthrough; case ASCE_TYPE_SEGMENT: { @@ -1548,6 +1553,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, rc = gmap_shadow_pgt(sg, saddr, ste.val, *fake); if (rc) return rc; + kvm->stat.gmap_shadow_sg_entry++; } } /* Return the parent address of the page table */ @@ -1618,6 +1624,7 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg, pte.p |= dat_protection; if (!rc) rc = gmap_shadow_page(sg, saddr, __pte(pte.val)); + vcpu->kvm->stat.gmap_shadow_pg_entry++; ipte_unlock(vcpu->kvm); mmap_read_unlock(sg->mm); return rc; diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index b3f17e014cab..b42493110d76 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -66,7 +66,14 @@ const struct _kvm_stats_desc kvm_vm_stats_desc[] = { STATS_DESC_COUNTER(VM, inject_pfault_done), STATS_DESC_COUNTER(VM, inject_service_signal), STATS_DESC_COUNTER(VM, inject_virtio), - STATS_DESC_COUNTER(VM, aen_forward) + STATS_DESC_COUNTER(VM, aen_forward), + STATS_DESC_COUNTER(VM, gmap_shadow_reuse), + STATS_DESC_COUNTER(VM, gmap_shadow_create), + STATS_DESC_COUNTER(VM, gmap_shadow_r1_entry), + STATS_DESC_COUNTER(VM, gmap_shadow_r2_entry), + STATS_DESC_COUNTER(VM, gmap_shadow_r3_entry), + STATS_DESC_COUNTER(VM, gmap_shadow_sg_entry), + STATS_DESC_COUNTER(VM, gmap_shadow_pg_entry), }; const struct kvm_stats_header kvm_vm_stats_header = { diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 61499293c2ac..02dcbe82a8e5 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -1214,8 +1214,10 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, * we're holding has been unshadowed. If the gmap is still valid, * we can safely reuse it. */ - if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) + if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) { + vcpu->kvm->stat.gmap_shadow_reuse++; return 0; + } /* release the old shadow - if any, and mark the prefix as unmapped */ release_gmap_shadow(vsie_page); @@ -1223,6 +1225,7 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, if (IS_ERR(gmap)) return PTR_ERR(gmap); gmap->private = vcpu->kvm; + vcpu->kvm->stat.gmap_shadow_create++; WRITE_ONCE(vsie_page->gmap, gmap); return 0; }