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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67976C433E0 for ; Tue, 30 Jun 2020 19:35:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 416302067D for ; Tue, 30 Jun 2020 19:35:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728179AbgF3Tfm (ORCPT ); Tue, 30 Jun 2020 15:35:42 -0400 Received: from mga05.intel.com ([192.55.52.43]:60496 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727883AbgF3Tfl (ORCPT ); Tue, 30 Jun 2020 15:35:41 -0400 IronPort-SDR: ZOJF+aLkFEpwJNP5Iz+/2Bki/OVwdNWpBnaFVd9aml5iHWUZaJzP7YFoJ91KjtZvkSlUOZDtd4 7bnzqBI8XXXA== X-IronPort-AV: E=McAfee;i="6000,8403,9668"; a="231232347" X-IronPort-AV: E=Sophos;i="5.75,298,1589266800"; d="scan'208";a="231232347" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jun 2020 12:35:41 -0700 IronPort-SDR: elbEF66KLsqgAltHscLNUbIrO614kmKeO9ANNqNxowpTqxofml1+JQC7FYMP2gbu3Ke22j3lmR a1ViNNSipw2g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,298,1589266800"; d="scan'208";a="321019680" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.152]) by FMSMGA003.fm.intel.com with ESMTP; 30 Jun 2020 12:35:40 -0700 Date: Tue, 30 Jun 2020 12:35:40 -0700 From: Sean Christopherson To: Aaron Lewis Cc: Krish Sadhukhan , Paolo Bonzini , kvm@vger.kernel.org, Nadav Amit Subject: Re: [kvm-unit-tests PATCH] x86: nVMX: Print more (accurate) info if RDTSC diff test fails Message-ID: <20200630193540.GH7733@linux.intel.com> References: <20200124234608.10754-1-sean.j.christopherson@intel.com> <705151e0-6a8b-1e15-934d-dd96f419dcd8@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Ping. On Mon, Jan 27, 2020 at 06:30:11AM -0800, Aaron Lewis wrote: > On Sat, Jan 25, 2020 at 11:16 PM Krish Sadhukhan > wrote: > > > > > > On 1/24/20 3:46 PM, Sean Christopherson wrote: > > > Snapshot the delta of the last run and display it in the report if the > > > test fails. Abort the run loop as soon as the threshold is reached so > > > that the displayed delta is guaranteed to a failed delta. Displaying > > > the delta helps triage failures, e.g. is my system completely broken or > > > did I get unlucky, and aborting the loop early saves 99900 runs when > > > the system is indeed broken. > > > > > > Cc: Nadav Amit > > > Cc: Aaron Lewis > > > Signed-off-by: Sean Christopherson > > > --- > > > x86/vmx_tests.c | 11 ++++++----- > > > 1 file changed, 6 insertions(+), 5 deletions(-) > > > > > > diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c > > > index b31c360..4049dec 100644 > > > --- a/x86/vmx_tests.c > > > +++ b/x86/vmx_tests.c > > > @@ -9204,6 +9204,7 @@ static unsigned long long rdtsc_vmexit_diff_test_iteration(void) > > > > > > static void rdtsc_vmexit_diff_test(void) > > > { > > > + unsigned long long delta; > > > int fail = 0; > > > int i; > > > > > > @@ -9226,17 +9227,17 @@ static void rdtsc_vmexit_diff_test(void) > > > vmcs_write(EXI_MSR_ST_CNT, 1); > > > vmcs_write(EXIT_MSR_ST_ADDR, virt_to_phys(exit_msr_store)); > > > > > > - for (i = 0; i < RDTSC_DIFF_ITERS; i++) { > > > - if (rdtsc_vmexit_diff_test_iteration() >= > > > - HOST_CAPTURED_GUEST_TSC_DIFF_THRESHOLD) > > > + for (i = 0; i < RDTSC_DIFF_ITERS && fail < RDTSC_DIFF_FAILS; i++) { > > > + delta = rdtsc_vmexit_diff_test_iteration(); > > > + if (delta >= HOST_CAPTURED_GUEST_TSC_DIFF_THRESHOLD) > > > fail++; > > > } > > > > > > enter_guest(); > > > > > > report(fail < RDTSC_DIFF_FAILS, > > > - "RDTSC to VM-exit delta too high in %d of %d iterations", > > > - fail, RDTSC_DIFF_ITERS); > > > + "RDTSC to VM-exit delta too high in %d of %d iterations, last = %llu", > > > + fail, i, delta); > > > } > > > > > > static int invalid_msr_init(struct vmcs *vmcs) > > Reviewed-by: Krish Sadhukhan > > Reviewed-by: Aaron Lewis