From patchwork Fri Jun 2 16:09:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vipin Sharma X-Patchwork-Id: 13265580 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 4DBDAC77B7A for ; Fri, 2 Jun 2023 16:09:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236489AbjFBQJc (ORCPT ); Fri, 2 Jun 2023 12:09:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35000 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236507AbjFBQJ3 (ORCPT ); Fri, 2 Jun 2023 12:09:29 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55751E40 for ; Fri, 2 Jun 2023 09:09:26 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id 41be03b00d2f7-53fa457686eso2055225a12.0 for ; Fri, 02 Jun 2023 09:09:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1685722166; x=1688314166; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=U16a7SsqQ7yjyv5J8Y2N4u7Ylkl11H9qatwpuhmZUgo=; b=636YoGkhL1EaD07rsMfPK9rB926Ht76M8pVZszNcRp8cSFBaHFxW4ESJErvKH1m1wQ b8SVVb+49Lm4c7lpuGUxvabzksatMUh3aHtTfXuucGjqsfAbB7x8jB5X+IIkfWd/B+pM hI1Jypk91JlkfEFB2dbGzi8Bjd9QmphZBvbPzeFfXopwyd64oFIEk7hcFeTi49fzsYb0 jMhjapC0h8n44W4QCQ7q/RI4lKIJPywJjobPFbGliUK4+jwpyLj3v9rdAbRrHTavotzv jSbTLKdo3Rd++6WRrKKX3ZluUSmLDy9wL6sxwwb/x/fXUrLPPNX7BCJ2JivFRXiwGY+V XR9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685722166; x=1688314166; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=U16a7SsqQ7yjyv5J8Y2N4u7Ylkl11H9qatwpuhmZUgo=; b=b1fXsAJ3c3wNtmk2wdeyiBUE8Xv1/5mOSaA/6sRTP7MV5ts14kbI741ny4er2A9Vzi +MCdNFv1pH0iHWy0IDIe6KGk8DKlJJhmtyfdQ1IZwZzDC0umQLHFof8I2bQSfNiX2Vpc cSYlJwj+SvXGEIX8LBVo1LcC8/dhNTYZ6Ax8SR2cDi1jOUk7n9wi0ov6geQ4Dph1He2P 7MEHYEPiFNMcjTmQnLERAwJrsFbVJ1qSOyWFT5yZS4fWfjGmuNF7gazmucxe9Wqzi9ui MaEUqsQVrExMCYw8rlqQjs3Tn7q3/GYasK590wtwqnJ79+MXj4jk3ZvUa4JBqMhnYxci /Z3g== X-Gm-Message-State: AC+VfDwK9AotbQ32NJlEyGutXQ+VLgpZAbEbxtb3uYJCWbk4VGCQd6eY XpEytz0eGHOeqNqVDcOqprvhdA6nqw0y X-Google-Smtp-Source: ACHHUZ5ZPLDaNjdv6ql0/d9oDMUgHRd2fE1fBqzKriMYD3yXbiA53bpGux4rVDyMUkeRamgRC/kjMfQm5qU6 X-Received: from vipin.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:479f]) (user=vipinsh job=sendgmr) by 2002:a17:90a:de04:b0:24e:18ff:5bad with SMTP id m4-20020a17090ade0400b0024e18ff5badmr42850pjv.0.1685722165847; Fri, 02 Jun 2023 09:09:25 -0700 (PDT) Date: Fri, 2 Jun 2023 09:09:01 -0700 In-Reply-To: <20230602160914.4011728-1-vipinsh@google.com> Mime-Version: 1.0 References: <20230602160914.4011728-1-vipinsh@google.com> X-Mailer: git-send-email 2.41.0.rc0.172.g3f132b7071-goog Message-ID: <20230602160914.4011728-4-vipinsh@google.com> Subject: [PATCH v2 03/16] KVM: selftests: Pass the count of read and write accesses from guest to host From: Vipin Sharma To: maz@kernel.org, oliver.upton@linux.dev, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, chenhuacai@kernel.org, aleksandar.qemu.devel@gmail.com, tsbogend@alpha.franken.de, anup@brainfault.org, atishp@atishpatra.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, seanjc@google.com, pbonzini@redhat.com, dmatlack@google.com, ricarkol@google.com Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Vipin Sharma Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Pass the number of read and write accesses done in the memstress guest code to userspace. These counts will provide a way to measure vCPUs performance during memstress and dirty logging related tests. For example, in dirty_log_perf_test this can be used to measure how much progress vCPUs are able to do while VMM is getting and clearing dirty logs. In dirty_log_perf_test, each vCPU runs once and then waits until iteration value is incremented by main thread, therefore, these access counts will not provide much useful information except for observing read vs write counts. However, in future commits, dirty_log_perf_test behavior will be changed to allow vCPUs to execute independent of userspace iterations. This will mimic real world workload where guest keeps on executing while VMM is collecting and clearing dirty logs separately. With read and write accesses known for each vCPU, impact of get and clear dirty log APIs can be quantified. Note that access counts will not be 100% reliable in knowing vCPUs performances. Few things which can affect vCPU progress: 1. vCPUs are scheduled less by host 2. Userspace operations run for longer time which end up giving vCPUs more time to execute. Signed-off-by: Vipin Sharma --- tools/testing/selftests/kvm/lib/memstress.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/memstress.c b/tools/testing/selftests/kvm/lib/memstress.c index 5f1d3173c238..ac53cc6e36d7 100644 --- a/tools/testing/selftests/kvm/lib/memstress.c +++ b/tools/testing/selftests/kvm/lib/memstress.c @@ -49,6 +49,8 @@ void memstress_guest_code(uint32_t vcpu_idx) struct memstress_args *args = &memstress_args; struct memstress_vcpu_args *vcpu_args = &args->vcpu_args[vcpu_idx]; struct guest_random_state rand_state; + uint64_t write_access; + uint64_t read_access; uint64_t gva; uint64_t pages; uint64_t addr; @@ -64,6 +66,8 @@ void memstress_guest_code(uint32_t vcpu_idx) GUEST_ASSERT(vcpu_args->vcpu_idx == vcpu_idx); while (true) { + write_access = 0; + read_access = 0; for (i = 0; i < pages; i++) { if (args->random_access) page = guest_random_u32(&rand_state) % pages; @@ -72,13 +76,16 @@ void memstress_guest_code(uint32_t vcpu_idx) addr = gva + (page * args->guest_page_size); - if (guest_random_u32(&rand_state) % 100 < args->write_percent) + if (guest_random_u32(&rand_state) % 100 < args->write_percent) { *(uint64_t *)addr = 0x0123456789ABCDEF; - else + write_access++; + } else { READ_ONCE(*(uint64_t *)addr); + read_access++; + } } - GUEST_SYNC(1); + GUEST_SYNC_ARGS(1, read_access, write_access, 0, 0); } }