From patchwork Fri Nov 18 21:15:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Upton X-Patchwork-Id: 13048783 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 6BF5DC43219 for ; Fri, 18 Nov 2022 21:15:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230271AbiKRVP1 (ORCPT ); Fri, 18 Nov 2022 16:15:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230131AbiKRVP0 (ORCPT ); Fri, 18 Nov 2022 16:15:26 -0500 Received: from out2.migadu.com (out2.migadu.com [IPv6:2001:41d0:2:aacc::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 450D492B52; Fri, 18 Nov 2022 13:15:25 -0800 (PST) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1668806123; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xCYUGaupX5cvs453r6y2KLObby9QVEfhtajAIprPxEc=; b=Fx49S7ywYMGdFD/E2m89wuPcBkOOaNariIsk6xwrf0cC8m9A1le4R7byvtN8e9Zws+iYs4 PFX0XSDRyjA9eUO3YO0WryXgbm9Y/7dQX3OuDzGoihEHDD+vQVGQFlxiokm4Edj+bLtO/k TRm4SvgtwTlNem4WVM9PGCB4mGf+ZC4= From: Oliver Upton To: Marc Zyngier , James Morse , Alexandru Elisei , Paolo Bonzini , Shuah Khan Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kvmarm@lists.linux.dev, Sean Christopherson , Gavin Shan , Oliver Upton , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/2] KVM: selftests: Have perf_test_util signal when to stop vCPUs Date: Fri, 18 Nov 2022 21:15:02 +0000 Message-Id: <20221118211503.4049023-2-oliver.upton@linux.dev> In-Reply-To: <20221118211503.4049023-1-oliver.upton@linux.dev> References: <20221118211503.4049023-1-oliver.upton@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Signal that a test run is complete through perf_test_args instead of having tests open code a similar solution. Ensure that the field resets to false at the beginning of a test run as the structure is reused between test runs, eliminating a couple of bugs: access_tracking_perf_test hangs indefinitely on a subsequent test run, as 'done' remains true. The bug doesn't amount to much right now, as x86 supports a single guest mode. However, this is a precondition of enabling the test for other architectures with >1 guest mode, like arm64. memslot_modification_stress_test has the exact opposite problem, where subsequent test runs complete immediately as 'run_vcpus' remains false. Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson [oliver: added commit message, preserve spin_wait_for_next_iteration()] Signed-off-by: Oliver Upton Reviewed-by: Gavin Shan --- tools/testing/selftests/kvm/access_tracking_perf_test.c | 8 +------- tools/testing/selftests/kvm/include/perf_test_util.h | 3 +++ tools/testing/selftests/kvm/lib/perf_test_util.c | 3 +++ .../selftests/kvm/memslot_modification_stress_test.c | 6 +----- 4 files changed, 8 insertions(+), 12 deletions(-) diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c index 76c583a07ea2..942370d57392 100644 --- a/tools/testing/selftests/kvm/access_tracking_perf_test.c +++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c @@ -58,9 +58,6 @@ static enum { ITERATION_MARK_IDLE, } iteration_work; -/* Set to true when vCPU threads should exit. */ -static bool done; - /* The iteration that was last completed by each vCPU. */ static int vcpu_last_completed_iteration[KVM_MAX_VCPUS]; @@ -211,7 +208,7 @@ static bool spin_wait_for_next_iteration(int *current_iteration) int last_iteration = *current_iteration; do { - if (READ_ONCE(done)) + if (READ_ONCE(perf_test_args.stop_vcpus)) return false; *current_iteration = READ_ONCE(iteration); @@ -321,9 +318,6 @@ static void run_test(enum vm_guest_mode mode, void *arg) mark_memory_idle(vm, nr_vcpus); access_memory(vm, nr_vcpus, ACCESS_READ, "Reading from idle memory"); - /* Set done to signal the vCPU threads to exit */ - done = true; - perf_test_join_vcpu_threads(nr_vcpus); perf_test_destroy_vm(vm); } diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h index eaa88df0555a..536d7c3c3f14 100644 --- a/tools/testing/selftests/kvm/include/perf_test_util.h +++ b/tools/testing/selftests/kvm/include/perf_test_util.h @@ -40,6 +40,9 @@ struct perf_test_args { /* Run vCPUs in L2 instead of L1, if the architecture supports it. */ bool nested; + /* Test is done, stop running vCPUs. */ + bool stop_vcpus; + struct perf_test_vcpu_args vcpu_args[KVM_MAX_VCPUS]; }; diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c index 9618b37c66f7..ee3f499ccbd2 100644 --- a/tools/testing/selftests/kvm/lib/perf_test_util.c +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c @@ -267,6 +267,7 @@ void perf_test_start_vcpu_threads(int nr_vcpus, vcpu_thread_fn = vcpu_fn; WRITE_ONCE(all_vcpu_threads_running, false); + WRITE_ONCE(perf_test_args.stop_vcpus, false); for (i = 0; i < nr_vcpus; i++) { struct vcpu_thread *vcpu = &vcpu_threads[i]; @@ -289,6 +290,8 @@ void perf_test_join_vcpu_threads(int nr_vcpus) { int i; + WRITE_ONCE(perf_test_args.stop_vcpus, true); + for (i = 0; i < nr_vcpus; i++) pthread_join(vcpu_threads[i].thread, NULL); } diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c index bb1d17a1171b..3a5e4518307c 100644 --- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c +++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c @@ -34,8 +34,6 @@ static int nr_vcpus = 1; static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE; -static bool run_vcpus = true; - static void vcpu_worker(struct perf_test_vcpu_args *vcpu_args) { struct kvm_vcpu *vcpu = vcpu_args->vcpu; @@ -45,7 +43,7 @@ static void vcpu_worker(struct perf_test_vcpu_args *vcpu_args) run = vcpu->run; /* Let the guest access its memory until a stop signal is received */ - while (READ_ONCE(run_vcpus)) { + while (!READ_ONCE(perf_test_args.stop_vcpus)) { ret = _vcpu_run(vcpu); TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret); @@ -110,8 +108,6 @@ static void run_test(enum vm_guest_mode mode, void *arg) add_remove_memslot(vm, p->memslot_modification_delay, p->nr_memslot_modifications); - run_vcpus = false; - perf_test_join_vcpu_threads(nr_vcpus); pr_info("All vCPU threads joined\n");