From nobody Fri Apr 3 08:56:33 2026 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 1935EC54EE9 for ; Fri, 16 Sep 2022 04:52:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229938AbiIPEwu (ORCPT ); Fri, 16 Sep 2022 00:52:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229852AbiIPEw1 (ORCPT ); Fri, 16 Sep 2022 00:52:27 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B8C18A033A for ; Thu, 15 Sep 2022 21:52:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1663303942; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4hBSESNIRTX2l3ycxY+A1LVUqR6O1lHB2wRbQ2GxcqA=; b=GufWPRw+k/oovfXbzhEgzsBWtD+IarANjuZhAR2L6UFHmGhMe7+2kBYjDv2uBOz/su9kyz 42ysrb+nGQ0tTzkSUWHE70K98qwj8OIFNLDlQfd1Tth+PKJ1x5ehGVuKiIergyaGtNEgBk 5sHguopKUa+FS0WtCcN4k+ZXROPzgD4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-634-hod3l5eFNme1a9N10jnV7w-1; Fri, 16 Sep 2022 00:52:19 -0400 X-MC-Unique: hod3l5eFNme1a9N10jnV7w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E607785A583; Fri, 16 Sep 2022 04:52:17 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-126.bne.redhat.com [10.64.54.126]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A2131140EBF3; Fri, 16 Sep 2022 04:52:11 +0000 (UTC) From: Gavin Shan To: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org, linux-doc@vger.kernel.org, catalin.marinas@arm.com, linux-kselftest@vger.kernel.org, bgardon@google.com, shuah@kernel.org, corbet@lwn.net, maz@kernel.org, drjones@redhat.com, will@kernel.org, zhenyzha@redhat.com, dmatlack@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, peterx@redhat.com, oliver.upton@linux.dev, shan.gavin@gmail.com Subject: [PATCH v2 4/5] KVM: selftests: Clear dirty ring states between two modes in dirty_log_test Date: Fri, 16 Sep 2022 12:51:34 +0800 Message-Id: <20220916045135.154505-5-gshan@redhat.com> In-Reply-To: <20220916045135.154505-1-gshan@redhat.com> References: <20220916045135.154505-1-gshan@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" There are two states, which need to be cleared before next mode is executed. Otherwise, we will hit failure as the following messages indicate. - The variable 'dirty_ring_vcpu_ring_full' shared by main and vcpu thread. It's indicating if the vcpu exit due to full ring buffer. The value can be carried from previous mode (VM_MODE_P40V48_4K) to current one (VM_MODE_P40V48_64K) when VM_MODE_P40V48_16K isn't supported. - The current ring buffer index needs to be reset before next mode (VM_MODE_P40V48_64K) is executed. Otherwise, the stale value is carried from previous mode (VM_MODE_P40V48_4K). # ./dirty_log_test -M dirty-ring Setting log mode to: 'dirty-ring' Test iterations: 32, interval: 10 (ms) Testing guest mode: PA-bits:40, VA-bits:48, 4K pages guest physical test memory offset: 0xffbfffc000 : Dirtied 995328 pages Total bits checked: dirty (1012434), clear (7114123), track_next (966700) Testing guest mode: PA-bits:40, VA-bits:48, 64K pages guest physical test memory offset: 0xffbffc0000 vcpu stops because vcpu is kicked out... vcpu continues now. Notifying vcpu to continue Iteration 1 collected 0 pages vcpu stops because dirty ring is full... vcpu continues now. vcpu stops because dirty ring is full... vcpu continues now. vcpu stops because dirty ring is full... =3D=3D=3D=3D Test Assertion Failure =3D=3D=3D=3D dirty_log_test.c:369: cleared =3D=3D count pid=3D10541 tid=3D10541 errno=3D22 - Invalid argument 1 0x0000000000403087: dirty_ring_collect_dirty_pages at dirty_log_test= .c:369 2 0x0000000000402a0b: log_mode_collect_dirty_pages at dirty_log_test.c= :492 3 (inlined by) run_test at dirty_log_test.c:795 4 (inlined by) run_test at dirty_log_test.c:705 5 0x0000000000403a37: for_each_guest_mode at guest_modes.c:100 6 0x0000000000401ccf: main at dirty_log_test.c:938 7 0x0000ffff9ecd279b: ?? ??:0 8 0x0000ffff9ecd286b: ?? ??:0 9 0x0000000000401def: _start at ??:? Reset dirty pages (0) mismatch with collected (35566) Fix the issues by clearing 'dirty_ring_vcpu_ring_full' and the ring buffer index before next new mode is to be executed. Signed-off-by: Gavin Shan --- tools/testing/selftests/kvm/dirty_log_test.c | 27 ++++++++++++-------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/s= elftests/kvm/dirty_log_test.c index 9c883c94d478..7d91df7e036f 100644 --- a/tools/testing/selftests/kvm/dirty_log_test.c +++ b/tools/testing/selftests/kvm/dirty_log_test.c @@ -225,13 +225,15 @@ static void clear_log_create_vm_done(struct kvm_vm *v= m) } =20 static void dirty_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot, - void *bitmap, uint32_t num_pages) + void *bitmap, uint32_t num_pages, + uint32_t *unused) { kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap); } =20 static void clear_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot, - void *bitmap, uint32_t num_pages) + void *bitmap, uint32_t num_pages, + uint32_t *unused) { kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap); kvm_vm_clear_dirty_log(vcpu->vm, slot, bitmap, 0, num_pages); @@ -327,10 +329,9 @@ static void dirty_ring_continue_vcpu(void) } =20 static void dirty_ring_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot, - void *bitmap, uint32_t num_pages) + void *bitmap, uint32_t num_pages, + uint32_t *ring_buf_idx) { - /* We only have one vcpu */ - static uint32_t fetch_index =3D 0; uint32_t count =3D 0, cleared; bool continued_vcpu =3D false; =20 @@ -347,7 +348,8 @@ static void dirty_ring_collect_dirty_pages(struct kvm_v= cpu *vcpu, int slot, =20 /* Only have one vcpu */ count =3D dirty_ring_collect_one(vcpu_map_dirty_ring(vcpu), - slot, bitmap, num_pages, &fetch_index); + slot, bitmap, num_pages, + ring_buf_idx); =20 cleared =3D kvm_vm_reset_dirty_ring(vcpu->vm); =20 @@ -404,7 +406,8 @@ struct log_mode { void (*create_vm_done)(struct kvm_vm *vm); /* Hook to collect the dirty pages into the bitmap provided */ void (*collect_dirty_pages) (struct kvm_vcpu *vcpu, int slot, - void *bitmap, uint32_t num_pages); + void *bitmap, uint32_t num_pages, + uint32_t *ring_buf_idx); /* Hook to call when after each vcpu run */ void (*after_vcpu_run)(struct kvm_vcpu *vcpu, int ret, int err); void (*before_vcpu_join) (void); @@ -469,13 +472,14 @@ static void log_mode_create_vm_done(struct kvm_vm *vm) } =20 static void log_mode_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot, - void *bitmap, uint32_t num_pages) + void *bitmap, uint32_t num_pages, + uint32_t *ring_buf_idx) { struct log_mode *mode =3D &log_modes[host_log_mode]; =20 TEST_ASSERT(mode->collect_dirty_pages !=3D NULL, "collect_dirty_pages() is required for any log mode!"); - mode->collect_dirty_pages(vcpu, slot, bitmap, num_pages); + mode->collect_dirty_pages(vcpu, slot, bitmap, num_pages, ring_buf_idx); } =20 static void log_mode_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int er= r) @@ -694,6 +698,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) struct kvm_vcpu *vcpu; struct kvm_vm *vm; unsigned long *bmap; + uint32_t ring_buf_idx =3D 0; =20 if (!log_mode_supported()) { print_skip("Log mode '%s' not supported", @@ -769,6 +774,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) host_dirty_count =3D 0; host_clear_count =3D 0; host_track_next_count =3D 0; + WRITE_ONCE(dirty_ring_vcpu_ring_full, false); =20 pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu); =20 @@ -776,7 +782,8 @@ static void run_test(enum vm_guest_mode mode, void *arg) /* Give the vcpu thread some time to dirty some pages */ usleep(p->interval * 1000); log_mode_collect_dirty_pages(vcpu, TEST_MEM_SLOT_INDEX, - bmap, host_num_pages); + bmap, host_num_pages, + &ring_buf_idx); =20 /* * See vcpu_sync_stop_requested definition for details on why --=20 2.23.0