From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C0CE036C581; Mon, 29 Jun 2026 11:00:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782730811; cv=none; b=VbOno/DsiIyFEMR+N59GkzYw0nd3imgBvx7GVvjvv/SqcXcJvS7TVbgHBfDpmv7ir/KVYtRBH6O1yvyvh8ol+iztTYe3+Q7FlFJ/ukil836y9oPVoqMW0kLV8eODR7KCYOHXsbOuFf8gUq7ypEiH+ci5uCsAOybKy2A9mI5lNhQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782730811; c=relaxed/simple; bh=vD5t4myi9oJDJdNcFVXUTZXWYgyBoCs4Pw49UWZH2P4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t4FNdeZS/oCJz+uyuQbcHi7pTpSOGuhp+X/q3nXU3uEdBsi6Q40YR2Bx+RE0qfUzmc9mfo1faMQgPL7gQ6+DI2EAdrNeH7Et12+0zgUY3fQSOfBMT19fs9fx1Lfirmu23r2DSgRNdd72ykUfm51WymgUMpPyI+m4Z88HaK70g3w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=rBxQ0+1k; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="rBxQ0+1k" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A5C861A00; Mon, 29 Jun 2026 04:00:04 -0700 (PDT) Received: from LeoBrasDK.cambridge.arm.com (LeoBrasDK.cambridge.arm.com [10.2.212.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6EED73F836; Mon, 29 Jun 2026 04:00:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782730809; bh=vD5t4myi9oJDJdNcFVXUTZXWYgyBoCs4Pw49UWZH2P4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rBxQ0+1k4eFDX4eFuvS2U7Rtida71YLSUJaFn5YwrkaLVrh/oG3PC6Zkkhwl/jETN dD28HKYwTTZaTHXZvmX9wQU2RfGdxLGJXBKmMEgbELta+D9Acllx3z3hJsBGbSVfqL 89zsBZAdPDIUkZYAHfO8YFXqqSd24XLlT7v8I4E4= From: Leonardo Bras To: Paolo Bonzini , Shuah Khan , Sean Christopherson , David Matlack , Leonardo Bras , Ackerley Tng , Oliver Upton , Marc Zyngier , Wu Fei , Steffen Eiden , Claudio Imbrenda Cc: kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH v2 1/3] KVM: selftests: memstress: Add option to enable dirty-ring on VM creation Date: Mon, 29 Jun 2026 11:59:40 +0100 Message-ID: <20260629105950.1790259-2-leo.bras@arm.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260629105950.1790259-1-leo.bras@arm.com> References: <20260629105950.1790259-1-leo.bras@arm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=10663; i=leo.bras@arm.com; h=from:subject; bh=vD5t4myi9oJDJdNcFVXUTZXWYgyBoCs4Pw49UWZH2P4=; b=owGbwMvMwCX2pizjszvTwvWMp9WSGLKc/CtuLFqc/qtDOSds52+t3Ls/5Som7D+0vSDlXEShz n/VhacFOkpZGMS4GGTFFFlkH81fxfN9SsaRKz8WwMxhZQIZwsDFKQATiTdlZNjB5h3HPbXlzNfs vmf9wS7qsz3V5Z7Ll7kV+bvmre/38Wf4K/Lpd+AMd63AySdaQ249P7XgVb50VXjW3nb7MLGs//y dTAA= X-Developer-Key: i=leo.bras@arm.com; a=openpgp; fpr=36E6C95AE0F111CC5B6F4D2E688C33F8A0C5B0C5 Content-Transfer-Encoding: 8bit Dirty-ring should be enabled after the VM is created, but before the creation of any cpu. To to so, add an option on memstress_create_vm() that takes dirty-ring size, and enables it at the correct moment. This required a new function memstress_vm_create_with_vcpus() to be created based on the previously used __vm_create_with_vcpus(); Signed-off-by: Leonardo Bras --- .../testing/selftests/kvm/include/memstress.h | 3 +- .../selftests/kvm/access_tracking_perf_test.c | 2 +- .../selftests/kvm/demand_paging_test.c | 2 +- .../selftests/kvm/dirty_log_perf_test.c | 2 +- tools/testing/selftests/kvm/lib/memstress.c | 34 ++++++++++++++++--- .../kvm/memslot_modification_stress_test.c | 2 +- .../kvm/x86/dirty_log_page_splitting_test.c | 2 +- 7 files changed, 37 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/kvm/include/memstress.h b/tools/testing/selftests/kvm/include/memstress.h index 0d1d6230cc05..e17f344978af 100644 --- a/tools/testing/selftests/kvm/include/memstress.h +++ b/tools/testing/selftests/kvm/include/memstress.h @@ -51,21 +51,22 @@ struct memstress_args { bool stop_vcpus; struct memstress_vcpu_args vcpu_args[KVM_MAX_VCPUS]; }; extern struct memstress_args memstress_args; struct kvm_vm *memstress_create_vm(enum vm_guest_mode mode, int nr_vcpus, u64 vcpu_memory_bytes, int slots, enum vm_mem_backing_src_type backing_src, - bool partition_vcpu_memory_access); + bool partition_vcpu_memory_access, + u32 dirty_ring_size); void memstress_destroy_vm(struct kvm_vm *vm); void memstress_set_write_percent(struct kvm_vm *vm, u32 write_percent); void memstress_set_random_access(struct kvm_vm *vm, bool random_access); void memstress_start_vcpu_threads(int vcpus, void (*vcpu_fn)(struct memstress_vcpu_args *)); void memstress_join_vcpu_threads(int vcpus); void memstress_guest_code(u32 vcpu_id); u64 memstress_nested_pages(int nr_vcpus); diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c index 4415c94b2866..f78d56265d89 100644 --- a/tools/testing/selftests/kvm/access_tracking_perf_test.c +++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c @@ -402,21 +402,21 @@ static void mark_memory_idle(struct kvm_vm *vm, int nr_vcpus) run_iteration(vm, nr_vcpus, "Mark memory idle (page_idle)"); } static void run_test(enum vm_guest_mode mode, void *arg) { struct test_params *params = arg; struct kvm_vm *vm; int nr_vcpus = params->nr_vcpus; vm = memstress_create_vm(mode, nr_vcpus, params->vcpu_memory_bytes, 1, - params->backing_src, !overlap_memory_access); + params->backing_src, !overlap_memory_access, 0); /* * If guest_page_size is larger than the host's page size, the * guest (memstress) will only fault in a subset of the host's pages. */ test_pages = params->nr_vcpus * params->vcpu_memory_bytes / max(memstress_args.guest_page_size, (u64)getpagesize()); memstress_start_vcpu_threads(nr_vcpus, vcpu_thread_main); diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c index 302c4923d093..92246e27ef74 100644 --- a/tools/testing/selftests/kvm/demand_paging_test.c +++ b/tools/testing/selftests/kvm/demand_paging_test.c @@ -155,21 +155,21 @@ static void run_test(enum vm_guest_mode mode, void *arg) struct test_params *p = arg; struct uffd_desc **uffd_descs = NULL; u64 uffd_region_size; struct timespec start; struct timespec ts_diff; double vcpu_paging_rate; struct kvm_vm *vm; int i, num_uffds = 0; vm = memstress_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 1, - p->src_type, p->partition_vcpu_memory_access); + p->src_type, p->partition_vcpu_memory_access, 0); demand_paging_size = get_backing_src_pagesz(p->src_type); guest_data_prototype = malloc(demand_paging_size); TEST_ASSERT(guest_data_prototype, "Failed to allocate buffer for guest data pattern"); memset(guest_data_prototype, 0xAB, demand_paging_size); if (p->uffd_mode == UFFDIO_REGISTER_MODE_MINOR) { num_uffds = p->single_uffd ? 1 : nr_vcpus; diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c index ef779fa91827..69b38791440e 100644 --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c @@ -112,21 +112,21 @@ static void run_test(enum vm_guest_mode mode, void *arg) struct timespec start; struct timespec ts_diff; struct timespec get_dirty_log_total = (struct timespec){0}; struct timespec vcpu_dirty_total = (struct timespec){0}; struct timespec avg; struct timespec clear_dirty_log_total = (struct timespec){0}; int i; vm = memstress_create_vm(mode, nr_vcpus, guest_percpu_mem_size, p->slots, p->backing_src, - p->partition_vcpu_memory_access); + p->partition_vcpu_memory_access, 0); memstress_set_write_percent(vm, p->write_percent); guest_num_pages = (nr_vcpus * guest_percpu_mem_size) >> vm->page_shift; guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages); host_num_pages = vm_num_host_pages(mode, guest_num_pages); pages_per_slot = host_num_pages / p->slots; bitmaps = memstress_alloc_bitmaps(p->slots, pages_per_slot); diff --git a/tools/testing/selftests/kvm/lib/memstress.c b/tools/testing/selftests/kvm/lib/memstress.c index 6dcd15910a06..c9f85533ffff 100644 --- a/tools/testing/selftests/kvm/lib/memstress.c +++ b/tools/testing/selftests/kvm/lib/memstress.c @@ -114,24 +114,49 @@ void memstress_setup_vcpus(struct kvm_vm *vm, int nr_vcpus, } vcpu_args_set(vcpus[i], 1, i); pr_debug("Added VCPU %d with test mem gpa [%lx, %lx)\n", i, vcpu_args->gpa, vcpu_args->gpa + (vcpu_args->pages * args->guest_page_size)); } } +static struct kvm_vm *memstress_vm_create_with_vcpus(struct vm_shape shape, + u32 nr_vcpus, + u64 extra_mem_pages, + void *guest_code, + struct kvm_vcpu *vcpus[], + u32 dirty_ring_size) +{ + struct kvm_vm *vm; + int i; + + TEST_ASSERT(!nr_vcpus || vcpus, "Must provide vCPU array"); + + vm = __vm_create(shape, nr_vcpus, extra_mem_pages); + + if (dirty_ring_size) + vm_enable_dirty_ring(vm, dirty_ring_size); + + for (i = 0; i < nr_vcpus; ++i) + vcpus[i] = vm_vcpu_add(vm, i, guest_code); + + kvm_arch_vm_finalize_vcpus(vm); + return vm; +} + struct kvm_vm *memstress_create_vm(enum vm_guest_mode mode, int nr_vcpus, u64 vcpu_memory_bytes, int slots, enum vm_mem_backing_src_type backing_src, - bool partition_vcpu_memory_access) + bool partition_vcpu_memory_access, + u32 dirty_ring_size) { struct memstress_args *args = &memstress_args; struct kvm_vm *vm; u64 guest_num_pages, slot0_pages = 0; u64 backing_src_pagesz = get_backing_src_pagesz(backing_src); u64 region_end_gfn; int i; pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode)); @@ -160,23 +185,24 @@ struct kvm_vm *memstress_create_vm(enum vm_guest_mode mode, int nr_vcpus, * in-memory data structures. */ if (args->nested) slot0_pages += memstress_nested_pages(nr_vcpus); /* * Pass guest_num_pages to populate the page tables for test memory. * The memory is also added to memslot 0, but that's a benign side * effect as KVM allows aliasing HVAs in meslots. */ - vm = __vm_create_with_vcpus(VM_SHAPE(mode), nr_vcpus, - slot0_pages + guest_num_pages, - memstress_guest_code, vcpus); + vm = memstress_vm_create_with_vcpus(VM_SHAPE(mode), nr_vcpus, + slot0_pages + guest_num_pages, + memstress_guest_code, vcpus, + dirty_ring_size); args->vm = vm; /* Put the test region at the top guest physical memory. */ region_end_gfn = vm->max_gfn + 1; #ifdef __x86_64__ /* * When running vCPUs in L2, restrict the test region to 48 bits to * avoid needing 5-level page tables to identity map L2. diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c index 9c7578a098c3..3a1be9b75e01 100644 --- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c +++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c @@ -83,21 +83,21 @@ struct test_params { bool disable_slot_zap_quirk; }; static void run_test(enum vm_guest_mode mode, void *arg) { struct test_params *p = arg; struct kvm_vm *vm; vm = memstress_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 1, VM_MEM_SRC_ANONYMOUS, - p->partition_vcpu_memory_access); + p->partition_vcpu_memory_access, 0); #ifdef __x86_64__ if (p->disable_slot_zap_quirk) vm_enable_cap(vm, KVM_CAP_DISABLE_QUIRKS2, KVM_X86_QUIRK_SLOT_ZAP_ALL); pr_info("Memslot zap quirk %s\n", p->disable_slot_zap_quirk ? "disabled" : "enabled"); #endif pr_info("Finished creating vCPUs\n"); diff --git a/tools/testing/selftests/kvm/x86/dirty_log_page_splitting_test.c b/tools/testing/selftests/kvm/x86/dirty_log_page_splitting_test.c index 388ba4101f97..661e9abfb439 100644 --- a/tools/testing/selftests/kvm/x86/dirty_log_page_splitting_test.c +++ b/tools/testing/selftests/kvm/x86/dirty_log_page_splitting_test.c @@ -94,21 +94,21 @@ static void run_test(enum vm_guest_mode mode, void *unused) u64 pages_per_slot; int i; struct kvm_page_stats stats_populated; struct kvm_page_stats stats_dirty_logging_enabled; struct kvm_page_stats stats_dirty_pass[ITERATIONS]; struct kvm_page_stats stats_clear_pass[ITERATIONS]; struct kvm_page_stats stats_dirty_logging_disabled; struct kvm_page_stats stats_repopulated; vm = memstress_create_vm(mode, VCPUS, guest_percpu_mem_size, - SLOTS, backing_src, false); + SLOTS, backing_src, false, 0); guest_num_pages = (VCPUS * guest_percpu_mem_size) >> vm->page_shift; guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages); host_num_pages = vm_num_host_pages(mode, guest_num_pages); pages_per_slot = host_num_pages / SLOTS; TEST_ASSERT_EQ(host_num_pages, pages_per_slot * SLOTS); TEST_ASSERT(!(host_num_pages % 512), "Number of pages, '%lu' not a multiple of 2MiB", host_num_pages); bitmaps = memstress_alloc_bitmaps(SLOTS, pages_per_slot); -- 2.54.0