From patchwork Mon Sep 4 13:01:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nico Boehr X-Patchwork-Id: 13373886 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 9368CC71153 for ; Mon, 4 Sep 2023 13:31:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350304AbjIDNbN (ORCPT ); Mon, 4 Sep 2023 09:31:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231185AbjIDNbM (ORCPT ); Mon, 4 Sep 2023 09:31:12 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 689FCCD5; Mon, 4 Sep 2023 06:31:08 -0700 (PDT) Received: from pps.filterd (m0353729.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 384C7Zdx016984; Mon, 4 Sep 2023 13:31:08 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=MNs0+dXUJXtLRzWXB96kKWiutdZWmFuySVe7ddzp05M=; b=j4ZpO40RFZicRfTPKky5kW+6Cpu88+4o19YkBnb5QoMkJEwCEO8ALob9WJMNgGuF0vJL TUPPjpoM00b6GxKP2K+r+qRCtb2znK8wZSLOh0u6cm9jkHAxWK0qVhIoECtKAk1lpWn7 8Cy1my7tX0X/CIRuqPSHYmXUsAftQ4052yBdNhVXnN5O8AIuNiL49cj12sGc97G+Qsq4 YWa+FvRO/lL0g/0knowthLJHZWv1aAdEkage1SMPaSC8Uc0fMzhoj6pTzxzjJ1XJN8WB GS0VYdqmbktxHdDFJavaJ+nVz9GRUkTImlM5328B/0YN5e3aZmw2s9CeZ+vXs8N4twlE bQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3sw80jbqhy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 04 Sep 2023 13:31:07 +0000 Received: from m0353729.ppops.net (m0353729.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 384DQYn4005890; Mon, 4 Sep 2023 13:31:07 GMT Received: from ppma11.dal12v.mail.ibm.com (db.9e.1632.ip4.static.sl-reverse.com [50.22.158.219]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3sw80jbqdk-11 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 04 Sep 2023 13:31:07 +0000 Received: from pps.filterd (ppma11.dal12v.mail.ibm.com [127.0.0.1]) by ppma11.dal12v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 384BWeZx011121; Mon, 4 Sep 2023 13:01:44 GMT Received: from smtprelay01.fra02v.mail.ibm.com ([9.218.2.227]) by ppma11.dal12v.mail.ibm.com (PPS) with ESMTPS id 3svj31a6uy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 04 Sep 2023 13:01:44 +0000 Received: from smtpav03.fra02v.mail.ibm.com (smtpav03.fra02v.mail.ibm.com [10.20.54.102]) by smtprelay01.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 384D1fr06554172 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 4 Sep 2023 13:01:41 GMT Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 868092004D; Mon, 4 Sep 2023 13:01:41 +0000 (GMT) Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4B87A2004E; Mon, 4 Sep 2023 13:01:41 +0000 (GMT) Received: from t35lp63.lnxne.boe (unknown [9.152.108.100]) by smtpav03.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 4 Sep 2023 13:01:41 +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 v3 1/2] KVM: s390: add stat counter for shadow gmap events Date: Mon, 4 Sep 2023 15:01:38 +0200 Message-ID: <20230904130140.22006-2-nrb@linux.ibm.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230904130140.22006-1-nrb@linux.ibm.com> References: <20230904130140.22006-1-nrb@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: rIhFc5ItFPibY9MYN3tp2OGnzo0RPyy1 X-Proofpoint-ORIG-GUID: eNwbZ5EteVcfoiGBhr7nFgIKE7xaqHMF X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.957,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-04_07,2023-08-31_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 bulkscore=0 mlxlogscore=999 suspectscore=0 spamscore=0 mlxscore=0 impostorscore=0 priorityscore=1501 adultscore=0 clxscore=1015 malwarescore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309040117 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 --- 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 91bfecb91321..5243cbd57e2f 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 d1e768bcfe1d..9379471081fa 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; }