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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 4AB4EC432BE for ; Mon, 23 Aug 2021 19:37:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2EFEB61378 for ; Mon, 23 Aug 2021 19:37:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232289AbhHWTiW (ORCPT ); Mon, 23 Aug 2021 15:38:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45198 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232169AbhHWTiN (ORCPT ); Mon, 23 Aug 2021 15:38:13 -0400 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 628F4C061575 for ; Mon, 23 Aug 2021 12:37:30 -0700 (PDT) Received: by mail-qv1-xf4a.google.com with SMTP id bo13-20020a05621414adb029035561c68664so13194926qvb.1 for ; Mon, 23 Aug 2021 12:37:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=rmYIpDdU3QK7p6S3HsrzN12lySY7VGfi8e7ewdZ2wvA=; b=wJL7Xz9VU1rOK6hlGPydrdtHKr/VbFayeoZuxgI/pClqesV+XUtE4QUu6XbrrGKUZV ITPHTHT20kry0avyUfIqLBA5JQIDxHabRE0taMXo5NdR5kv+wryPWEN84fvWo+bgfMCk gsHovFqh4jAGff4gsw+zhuTuVahcourpbCDWAlPWtNjHNgrYonayLLqtPlPy7tWmSIYj SV2v2u/HMZREXghd0Hpq/8lks5BDnj089jgrDv/KYMCPEauxiUC5forh8V9GGgO1yjGr oWDhGoeu9Dc2hqnIrJJb0hakosarXIXsCuDxJGiDyZkJO4UhCloFjVRUdM2sYTUdJq/C CGng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=rmYIpDdU3QK7p6S3HsrzN12lySY7VGfi8e7ewdZ2wvA=; b=I/vA1bpgYMKldXpfHoE/6SWmUuqWi6ea4YxTppKSiFmrzUbejPo2R/cbpgq5xmgFSX OqVcA6Z+EYN4uBWcHt14/aKcMBQSpxsNfyzFMdLIOda0wkBReFHRYA3nWiSOEtFOZS6J UEtWe1jGC13008waHCAl7hnG1fdBufAfwhY/+x1PYdEW+huBzRH/kxPr6IpqJCKB/gXp ELFSc2K2G2R53L3H7RLMFlXb8ntByBfKZXt91HZ7++fBXbzSs1A9IePQVc+k37DLG3h8 YHUNpDjxX3k8KmP9x2HJCq/IRRKZZ5FWP4O+q/s/ATHEzrnZgyL8mAUnNkLsw50LPRXT CYCA== X-Gm-Message-State: AOAM531kvv7kQkEXTj/stVe+ltTIJKuvo7Eu4/V9HgNe66Z6sJ/6gOqt wenrIo00ju5p/JacFTPfQSiWbXjT2/Y= X-Google-Smtp-Source: ABdhPJxMughRTeNGSfkS7sQ5RCx/BDaAhNO0JOHhWF1MAuK3EB9WU/08l/gP2MCeN22B+W0LyWkDmS1X6TU= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:90:200:109c:7eb8:d5ed:2e59]) (user=seanjc job=sendgmr) by 2002:a05:6214:312:: with SMTP id i18mr2221144qvu.48.1629747449581; Mon, 23 Aug 2021 12:37:29 -0700 (PDT) Reply-To: Sean Christopherson Date: Mon, 23 Aug 2021 12:37:09 -0700 In-Reply-To: <20210823193709.55886-1-seanjc@google.com> Message-Id: <20210823193709.55886-4-seanjc@google.com> Mime-Version: 1.0 References: <20210823193709.55886-1-seanjc@google.com> X-Mailer: git-send-email 2.33.0.rc2.250.ged5fa647cd-goog Subject: [PATCH 3/3] perf/x86/intel: Fold current_vcpu check into KVM's PT intr handler From: Sean Christopherson To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Paolo Bonzini Cc: Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Artem Kashkanov Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Move the check for a non-NULL current_vcpu into KVM's PT intr handler instead of relying on the caller to perform the check. In addition to ensuring KVM's handler won't dereference a NULL pointer (and making it obvious that it can't), this avoids a reptoline when KVM is configured to run PT in "system mode", in which case handle_intel_pt_intr will be NULL. No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/events/intel/core.c | 7 +++---- arch/x86/kvm/pmu.h | 2 +- arch/x86/kvm/x86.c | 6 +++++- include/linux/perf_event.h | 2 +- 4 files changed, 10 insertions(+), 7 deletions(-) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index fca7a6e2242f..060f1f1ebe15 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2852,10 +2852,9 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status) */ if (__test_and_clear_bit(GLOBAL_STATUS_TRACE_TOPAPMI_BIT, (unsigned long *)&status)) { handled++; - if (unlikely(perf_guest_cbs && perf_guest_cbs->is_in_guest() && - perf_guest_cbs->handle_intel_pt_intr)) - perf_guest_cbs->handle_intel_pt_intr(); - else + if (likely(!perf_guest_cbs || + !perf_guest_cbs->handle_intel_pt_intr || + perf_guest_cbs->handle_intel_pt_intr())) intel_pt_interrupt(); } diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h index b06dbbd7eeeb..4e8a38eca72b 100644 --- a/arch/x86/kvm/pmu.h +++ b/arch/x86/kvm/pmu.h @@ -41,7 +41,7 @@ struct kvm_pmu_ops { void (*reset)(struct kvm_vcpu *vcpu); void (*deliver_pmi)(struct kvm_vcpu *vcpu); void (*cleanup)(struct kvm_vcpu *vcpu); - void (*handle_intel_pt_intr)(void); + int (*handle_intel_pt_intr)(void); }; static inline u64 pmc_bitmask(struct kvm_pmc *pmc) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b5ade47dad9c..3f289192f25f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8292,13 +8292,17 @@ static unsigned long kvm_get_guest_ip(void) return ip; } -static void kvm_handle_intel_pt_intr(void) +static int kvm_handle_intel_pt_intr(void) { struct kvm_vcpu *vcpu = __this_cpu_read(current_vcpu); + if (!vcpu) + return -ENXIO; + kvm_make_request(KVM_REQ_PMI, vcpu); __set_bit(MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI_BIT, (unsigned long *)&vcpu->arch.pmu.global_status); + return 0; } static struct perf_guest_info_callbacks kvm_guest_cbs = { diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 2d510ad750ed..f812c2570285 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -30,7 +30,7 @@ struct perf_guest_info_callbacks { int (*is_in_guest)(void); int (*is_user_mode)(void); unsigned long (*get_guest_ip)(void); - void (*handle_intel_pt_intr)(void); + int (*handle_intel_pt_intr)(void); }; #ifdef CONFIG_HAVE_HW_BREAKPOINT -- 2.33.0.rc2.250.ged5fa647cd-goog