From mboxrd@z Thu Jan 1 00:00:00 1970 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 11E9EC433F5 for ; Wed, 23 Mar 2022 18:49:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344117AbiCWSv0 (ORCPT ); Wed, 23 Mar 2022 14:51:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344073AbiCWSvH (ORCPT ); Wed, 23 Mar 2022 14:51:07 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE1D260D8D for ; Wed, 23 Mar 2022 11:49:32 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id z10-20020a634c0a000000b0036c5eb39076so1091748pga.18 for ; Wed, 23 Mar 2022 11:49:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=c5fKyu9jH6XE+xJIVIS/L5W4c26nrxs3xWXA5jPM5YY=; b=C10LlrNWhm5bgZg0y2T/cSnRWn4NBv6Ijy73wn6fsYLtVEUL3MMaxw54JXOLlBTv5a rEp1JHZVuekBqV0GnPIZlSn42sL9jJxM5z2FiEMxawlv8e4IFUnLSht3LAgncURiXIv9 X03pTiQKbwSpWLbW/+uv9hfjxViNtYEzD9Q4TG5xr3CXpfkGhNIa9hYJQrjNuzueHEvb AmRBZAsmQpWTw5SkbcX5z4s1q7yCKJXgnGdcOnEiUi7GoBsWclCRnC1hxRxrFOOAAolz lC6jkplgy96DC+JPbcLIxIZLrEO9c7Lw65m4cw726nQuwRnrV++Y//AN7EwTVIB1HLcc 8ZBg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=c5fKyu9jH6XE+xJIVIS/L5W4c26nrxs3xWXA5jPM5YY=; b=7wL7TYpdPVTMSuRhrkGiujyzgaAjcZa1h9RHgC6p/A81mLM5kM+BYZgG0PAERcfkoc xQb0NUpX7/+l9uSKlr9p/1BtbLQ0WcKkY7A6M7bbsdtN0pphvRYLIl4Z49pZmzGdkjPs 1X3+CoCDY9VXbY1gZ6EoRZcLMxpZjqtLmTqCLYcPPcHzb/i2tHRi9FEAW4tOlduMM0u5 K7vfQqJpYRzk0go0+aSbVSlkHpmeCbmu44krzgzghAdAb84eyMa84i1huGrA5153bz3w UnHONr2fs7bPilZ8phIDyKvsz6caC/HNws+9SqC8EIszV3OVEKzZddV6sOunXiAj56we cO3A== X-Gm-Message-State: AOAM530DqN/hbfgFvcsyVh01PEBZPoLRSGMPklC4TCaa9Gf88V8PiaFZ fRKq4+AmN4UnvVi0zQg7421vXSgLdv+G X-Google-Smtp-Source: ABdhPJw3TuVBjn2xN6D1q57cS12a8wgK2abT8t4Ffi0TQtHWkk8eOzNArS5pVnsQWrxWouXWLqUKQflUznSt X-Received: from mizhang-super.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:1071]) (user=mizhang job=sendgmr) by 2002:a17:903:1d1:b0:154:61ec:749b with SMTP id e17-20020a17090301d100b0015461ec749bmr1495211plh.52.1648061372281; Wed, 23 Mar 2022 11:49:32 -0700 (PDT) Reply-To: Mingwei Zhang Date: Wed, 23 Mar 2022 18:49:15 +0000 In-Reply-To: <20220323184915.1335049-1-mizhang@google.com> Message-Id: <20220323184915.1335049-6-mizhang@google.com> Mime-Version: 1.0 References: <20220323184915.1335049-1-mizhang@google.com> X-Mailer: git-send-email 2.35.1.1021.g381101b075-goog Subject: [PATCH v2 4/4] selftests: KVM: use dirty logging to check if page stats work correctly From: Mingwei Zhang To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gardon , Mingwei Zhang , David Matlack , Jing Zhang , Peter Xu Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When dirty logging is enabled, KVM will remap all accessed pages in NPT/EPT at 4K. This property could be used to check if the page stats metrics work properly in KVM mmu. At the same time, this logic might be used the other way around: using page stats to verify if dirty logging really splits all huge pages. Moreover, when dirty logging is disabled, KVM zaps corresponding SPTEs and we could check whether the large pages come back when guest touches the pages again. So add page stats checking in dirty logging performance selftest. In particular, add checks in three locations: - just after vm is created; - after populating memory into vm but before enabling dirty logging; - finish dirty logging but before disabling it; - behind the final iteration after disabling dirty logging. Tested using commands: - ./dirty_log_perf_test -s anonymous_hugetlb_1gb - ./dirty_log_perf_test -s anonymous_hugetlb_2mb - ./dirty_log_perf_test -s anonymous_thp Cc: Sean Christopherson Cc: David Matlack Cc: Jing Zhang Cc: Peter Xu Suggested-by: Ben Gardon Signed-off-by: Mingwei Zhang --- .../selftests/kvm/dirty_log_perf_test.c | 53 +++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c index 1954b964d1cf..21431b0f5547 100644 --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c @@ -19,6 +19,10 @@ #include "perf_test_util.h" #include "guest_modes.h" +#ifdef __x86_64__ +#include "processor.h" +#endif + /* How many host loops to run by default (one KVM_GET_DIRTY_LOG for each loop)*/ #define TEST_HOST_LOOP_N 2UL @@ -185,6 +189,14 @@ static void run_test(enum vm_guest_mode mode, void *arg) p->slots, p->backing_src, p->partition_vcpu_memory_access); +#ifdef __x86_64__ + TEST_ASSERT(vm_get_single_stat(vm, "pages_4k") == 0, + "4K page is non zero"); + TEST_ASSERT(vm_get_single_stat(vm, "pages_2m") == 0, + "2M page is non zero"); + TEST_ASSERT(vm_get_single_stat(vm, "pages_1g") == 0, + "1G page is non zero"); +#endif perf_test_set_wr_fract(vm, p->wr_fract); guest_num_pages = (nr_vcpus * guest_percpu_mem_size) >> vm_get_page_shift(vm); @@ -222,6 +234,17 @@ static void run_test(enum vm_guest_mode mode, void *arg) pr_info("Populate memory time: %ld.%.9lds\n", ts_diff.tv_sec, ts_diff.tv_nsec); +#ifdef __x86_64__ + TEST_ASSERT(vm_get_single_stat(vm, "pages_4k") != 0, + "4K page is zero"); + if (p->backing_src == VM_MEM_SRC_ANONYMOUS_THP || + p->backing_src == VM_MEM_SRC_ANONYMOUS_HUGETLB_2MB) + TEST_ASSERT(vm_get_single_stat(vm, "pages_2m") != 0, + "2M page is zero"); + if (p->backing_src == VM_MEM_SRC_ANONYMOUS_HUGETLB_1GB) + TEST_ASSERT(vm_get_single_stat(vm, "pages_1g") != 0, + "1G page is zero"); +#endif /* Enable dirty logging */ clock_gettime(CLOCK_MONOTONIC, &start); enable_dirty_logging(vm, p->slots); @@ -267,6 +290,14 @@ static void run_test(enum vm_guest_mode mode, void *arg) iteration, ts_diff.tv_sec, ts_diff.tv_nsec); } } +#ifdef __x86_64__ + TEST_ASSERT(vm_get_single_stat(vm, "pages_4k") != 0, + "4K page is zero after dirty logging"); + TEST_ASSERT(vm_get_single_stat(vm, "pages_2m") == 0, + "2M page is non-zero after dirty logging"); + TEST_ASSERT(vm_get_single_stat(vm, "pages_1g") == 0, + "1G page is non-zero after dirty logging"); +#endif /* Disable dirty logging */ clock_gettime(CLOCK_MONOTONIC, &start); @@ -275,6 +306,28 @@ static void run_test(enum vm_guest_mode mode, void *arg) pr_info("Disabling dirty logging time: %ld.%.9lds\n", ts_diff.tv_sec, ts_diff.tv_nsec); + /* + * Increment iteration to run the vcpus again to ensure all pages come + * back. + */ + iteration++; + pr_info("Starting the final iteration to get all pages back.\n"); + for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { + while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) + != iteration) + ; + } + +#ifdef __x86_64__ + if (p->backing_src == VM_MEM_SRC_ANONYMOUS_THP || + p->backing_src == VM_MEM_SRC_ANONYMOUS_HUGETLB_2MB) + TEST_ASSERT(vm_get_single_stat(vm, "pages_2m") != 0, + "2M page is zero"); + if (p->backing_src == VM_MEM_SRC_ANONYMOUS_HUGETLB_1GB) + TEST_ASSERT(vm_get_single_stat(vm, "pages_1g") != 0, + "1G page is zero"); +#endif + /* Tell the vcpu thread to quit */ host_quit = true; perf_test_join_vcpu_threads(nr_vcpus); -- 2.35.1.1021.g381101b075-goog