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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 1CA9CC47255 for ; Fri, 8 May 2020 18:22:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F0D06208CA for ; Fri, 8 May 2020 18:22:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="FxsJIw9N" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727826AbgEHSWy (ORCPT ); Fri, 8 May 2020 14:22:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726636AbgEHSWx (ORCPT ); Fri, 8 May 2020 14:22:53 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D6F4C05BD09 for ; Fri, 8 May 2020 11:22:52 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id s8so3061261ybj.9 for ; Fri, 08 May 2020 11:22:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=36cGNYe6ShNCgmX+2LiEk2mbNEtHey09nCarODUPKds=; b=FxsJIw9Nqt2of5gMxoaFw1W5hQiw5NOsyI94lqgC266bKDNILq19UgSG5w7PXgRrbE tEnk/LbN8OeWhjwpNc3yIX06DHU3sX6I2Z6qayc2vyGJItJmHiv9Aw+67amIEZKFoEtI nLqj/LPIDOfTuflYf8wkrXz+YzA+NP9Lxq+KFL2UwshmYHeqUA97Qdzrgk8lN03yFNNI yRfLGzrUGvnWMf3zG/6CgdxABRGaZERY2CqLmrgb+FVZ8uM8VPR0a49PWW3gzC0rrfBD 70/ixtsW+4oHQDTfIW8regY68iFqpFaraMprEo+4jwC7Cc5Mkf4zD3ahYoo734Bbcq4v AgzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=36cGNYe6ShNCgmX+2LiEk2mbNEtHey09nCarODUPKds=; b=iBCNJsgqkjPsOK+DJcq1i45gx6WNvmobsluFNnykQKBo9Y+7FmdJWo9wSlLs15n72U 6feoWsudHgm4eomSmdATIHG6P2eLLAFMlBzq0M27aw67QFmNTVb4IQIVhWmNuxOV/CZq VGUGMzJuDaLPmB2tUA2/XExSgC1CG4l9kJWTpb2tufPXViSZKEGu9Wew78r9eLbnO+/N ceEAVgxijzRCSfbZLYwhq4aEMq7fR32D03nVRs23hoA1BKCsBQPiAb2eweGWubJA7d2a 8PtK9/IU6cPVd6h0r0m3nfHlmvLoSfQp6AL1yw32c0OVsw0phYIVOQFIdK/SoVzE9mAT J90A== X-Gm-Message-State: AGi0PuavD723RMO62+mcSnv1hRsLtZ60/mKVKCgcaZlBAfJP0CWj7GaT 3zX85oVor843Ik8bTIQIcMbRvtLgk5jScA== X-Google-Smtp-Source: APiQypKHnac9ibG0+zijqvOKATCu+FaUpuVnT1jlsq4K4eTgwmg4aYoNgIvp73R9IMCdQXmZuESLz5iLNgpzhw== X-Received: by 2002:a25:b9c5:: with SMTP id y5mr6305255ybj.421.1588962171430; Fri, 08 May 2020 11:22:51 -0700 (PDT) Date: Fri, 8 May 2020 11:22:40 -0700 Message-Id: <20200508182240.68440-1-jcargill@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.26.2.645.ge9eca65c58-goog Subject: [PATCH] kvm: add halt-polling cpu usage stats From: Jon Cargille To: Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: David Matlack , Jon Cargille Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Matlack Two new stats for exposing halt-polling cpu usage: halt_poll_success_ns halt_poll_fail_ns Thus sum of these 2 stats is the total cpu time spent polling. "success" means the VCPU polled until a virtual interrupt was delivered. "fail" means the VCPU had to schedule out (either because the maximum poll time was reached or it needed to yield the CPU). To avoid touching every arch's kvm_vcpu_stat struct, only update and export halt-polling cpu usage stats if we're on x86. Exporting cpu usage as a u64 and in nanoseconds means we will overflow at ~500 years, which seems reasonably large. Signed-off-by: David Matlack Signed-off-by: Jon Cargille Reviewed-by: Jim Mattson --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/x86.c | 2 ++ virt/kvm/kvm_main.c | 20 +++++++++++++++++--- 3 files changed, 21 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index a239a297be33..3287159ab15b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1032,6 +1032,8 @@ struct kvm_vcpu_stat { u64 irq_injections; u64 nmi_injections; u64 req_event; + u64 halt_poll_success_ns; + u64 halt_poll_fail_ns; }; struct x86_instruction_info; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8c0b77ac8dc6..9736d91ce877 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -217,6 +217,8 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { VCPU_STAT("nmi_injections", nmi_injections), VCPU_STAT("req_event", req_event), VCPU_STAT("l1d_flush", l1d_flush), + VCPU_STAT( "halt_poll_success_ns", halt_poll_success_ns), + VCPU_STAT( "halt_poll_fail_ns", halt_poll_fail_ns), VM_STAT("mmu_shadow_zapped", mmu_shadow_zapped), VM_STAT("mmu_pte_write", mmu_pte_write), VM_STAT("mmu_pte_updated", mmu_pte_updated), diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 33e1eee96f75..348b4a6bde53 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2664,19 +2664,30 @@ static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu) return ret; } +static inline void +update_halt_poll_stats(struct kvm_vcpu *vcpu, u64 poll_ns, bool waited) +{ +#ifdef CONFIG_X86 + if (waited) + vcpu->stat.halt_poll_fail_ns += poll_ns; + else + vcpu->stat.halt_poll_success_ns += poll_ns; +#endif +} + /* * The vCPU has executed a HLT instruction with in-kernel mode enabled. */ void kvm_vcpu_block(struct kvm_vcpu *vcpu) { - ktime_t start, cur; + ktime_t start, cur, poll_end; DECLARE_SWAITQUEUE(wait); bool waited = false; u64 block_ns; kvm_arch_vcpu_blocking(vcpu); - start = cur = ktime_get(); + start = cur = poll_end = ktime_get(); if (vcpu->halt_poll_ns && !kvm_arch_no_poll(vcpu)) { ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns); @@ -2692,7 +2703,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) ++vcpu->stat.halt_poll_invalid; goto out; } - cur = ktime_get(); + poll_end = cur = ktime_get(); } while (single_task_running() && ktime_before(cur, stop)); } @@ -2712,6 +2723,9 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) kvm_arch_vcpu_unblocking(vcpu); block_ns = ktime_to_ns(cur) - ktime_to_ns(start); + update_halt_poll_stats( + vcpu, ktime_to_ns(ktime_sub(poll_end, start)), waited); + if (!kvm_arch_no_poll(vcpu)) { if (!vcpu_valid_wakeup(vcpu)) { shrink_halt_poll_ns(vcpu); -- 2.26.2.303.gf8c07b1a785-goog