From patchwork Thu Nov 11 02:07:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12613851 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1C7BC433EF for ; Thu, 11 Nov 2021 02:08:27 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7F65D61073 for ; Thu, 11 Nov 2021 02:08:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7F65D61073 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.224513.387894 (Exim 4.92) (envelope-from ) id 1mkzVP-0006P6-Ak; Thu, 11 Nov 2021 02:07:59 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 224513.387894; Thu, 11 Nov 2021 02:07:59 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mkzVP-0006Ot-6U; Thu, 11 Nov 2021 02:07:59 +0000 Received: by outflank-mailman (input) for mailman id 224513; Thu, 11 Nov 2021 02:07:57 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mkzVN-0006EI-Ay for xen-devel@lists.xenproject.org; Thu, 11 Nov 2021 02:07:57 +0000 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [2607:f8b0:4864:20::44a]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 2e6bffdd-4294-11ec-a9d2-d9f7a1cc8784; Thu, 11 Nov 2021 03:07:55 +0100 (CET) Received: by mail-pf1-x44a.google.com with SMTP id m26-20020a62a21a000000b0041361973ba7so3025890pff.15 for ; Wed, 10 Nov 2021 18:07:55 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 2e6bffdd-4294-11ec-a9d2-d9f7a1cc8784 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=cLIsvkhrGBYnUpSNCNJBNYz6Cxw5ol9DR3GtAyee4XM=; b=UWY+I67x4udh62C37NhqjaJRirQ82H+O8Bapb8N9xQXR1hTzdZo/K1xEJqAq9rNDj8 /CEXnNB19mzJdGDaFjKWaLdtvzi33ZGiaWh3BQRjYo8B5CDiTZRBGviZpr9x+UfVIAkb sjbJ+B7yuNB9hFQXxpGBYeTQX2mmrHCcHAZg/4OVsnXBQaBdxMTg813r2Ch/7TjbpqY0 z8EX0rkQUlsj71pyKJ/d7eA5S4lz3YcnQAl7M8ewTb9Ej6PUeF4YEby2nGyPc1sOivTc CcHqA8McmQsBqqjCAzz1GDv/VgvIqfIMFjVh/1Y17Uc0kgMdlXYJzuPodkBR/eP+VOOR EOoA== 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=cLIsvkhrGBYnUpSNCNJBNYz6Cxw5ol9DR3GtAyee4XM=; b=uBD4w/+9P6A2Tjh22SNVlMolFIdjWxqM/UWKHeLJ6PtIUfXLAZ/n1+dKvUzqx3CINf grwoF0eZ8rz0AoJLOX7OB/dipiGlqopRLtznoSQVcpUrOmh4Ex2JIvhVfYWiHoLx4JcS GBiS/X+gbUG0c1obFKNoj8vICM61f+sv6sl15Yu4C7X1iZ2VT8H/Px+gRuPUpu2zZyeG DFQY3JuGltqc1alBgq1iIefDC2QyhJ6gra+JKODhTm8SLf2yWgFUxMplcZIZqkP6PQF8 BaIaqZol/6ioaHrqMRZKkCvJzKAsRubURRgfiyEq9PnF36L0UBr/rKsyxGlpoR16MLp4 yiOg== X-Gm-Message-State: AOAM532NPl9LLUphZLr1ywq0FVvL3z7fnws2QUgwaRjFVDIPTdiU2qGk o7f+kVNEEtSPs6WsOLXvLd8j4bDFptk= X-Google-Smtp-Source: ABdhPJyA+FPl1GrpuJCEY1SbbkGaO/jmn8V2FSIoEOOofvc+yyStyKbXUIFhESdIZSXyIeRcJnfvlG5Y2FI= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a17:90a:284f:: with SMTP id p15mr145050pjf.1.1636596472324; Wed, 10 Nov 2021 18:07:52 -0800 (PST) Reply-To: Sean Christopherson Date: Thu, 11 Nov 2021 02:07:28 +0000 In-Reply-To: <20211111020738.2512932-1-seanjc@google.com> Message-Id: <20211111020738.2512932-8-seanjc@google.com> Mime-Version: 1.0 References: <20211111020738.2512932-1-seanjc@google.com> X-Mailer: git-send-email 2.34.0.rc0.344.g81b53c2807-goog Subject: [PATCH v4 07/17] perf: Add wrappers for invoking guest callbacks From: Sean Christopherson To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Will Deacon , Mark Rutland , Russell King , Marc Zyngier , Catalin Marinas , Guo Ren , Nick Hu , Greentime Hu , Vincent Chen , Paul Walmsley , Palmer Dabbelt , Albert Ou , Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, Paolo Bonzini , Boris Ostrovsky , Juergen Gross Cc: Alexander Shishkin , Jiri Olsa , Namhyung Kim , James Morse , Alexandru Elisei , Suzuki K Poulose , "H. Peter Anvin" , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Stefano Stabellini , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-csky@vger.kernel.org, linux-riscv@lists.infradead.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, Artem Kashkanov , Like Xu , Like Xu , Zhu Lingshan Add helpers for the guest callbacks to prepare for burying the callbacks behind a Kconfig (it's a lot easier to provide a few stubs than to #ifdef piles of code), and also to prepare for converting the callbacks to static_call(). perf_instruction_pointer() in particular will have subtle semantics with static_call(), as the "no callbacks" case will return 0 if the callbacks are unregistered between querying guest state and getting the IP. Implement the change now to avoid a functional change when adding static_call() support, and because the new helper needs to return _something_ in this case. Reviewed-by: Paolo Bonzini Signed-off-by: Sean Christopherson --- arch/arm64/kernel/perf_callchain.c | 16 +++++----------- arch/x86/events/core.c | 15 +++++---------- arch/x86/events/intel/core.c | 5 +---- include/linux/perf_event.h | 24 ++++++++++++++++++++++++ 4 files changed, 35 insertions(+), 25 deletions(-) diff --git a/arch/arm64/kernel/perf_callchain.c b/arch/arm64/kernel/perf_callchain.c index 274dc3e11b6d..db04a55cee7e 100644 --- a/arch/arm64/kernel/perf_callchain.c +++ b/arch/arm64/kernel/perf_callchain.c @@ -102,9 +102,7 @@ compat_user_backtrace(struct compat_frame_tail __user *tail, void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); - - if (guest_cbs && guest_cbs->state()) { + if (perf_guest_state()) { /* We don't support guest os callchain now */ return; } @@ -149,10 +147,9 @@ static bool callchain_trace(void *data, unsigned long pc) void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); struct stackframe frame; - if (guest_cbs && guest_cbs->state()) { + if (perf_guest_state()) { /* We don't support guest os callchain now */ return; } @@ -163,18 +160,15 @@ void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, unsigned long perf_instruction_pointer(struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); - - if (guest_cbs && guest_cbs->state()) - return guest_cbs->get_ip(); + if (perf_guest_state()) + return perf_guest_get_ip(); return instruction_pointer(regs); } unsigned long perf_misc_flags(struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); - unsigned int guest_state = guest_cbs ? guest_cbs->state() : 0; + unsigned int guest_state = perf_guest_state(); int misc = 0; if (guest_state) { diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index e29312a1003a..620347398027 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2768,11 +2768,10 @@ static bool perf_hw_regs(struct pt_regs *regs) void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); struct unwind_state state; unsigned long addr; - if (guest_cbs && guest_cbs->state()) { + if (perf_guest_state()) { /* TODO: We don't support guest os callchain now */ return; } @@ -2872,11 +2871,10 @@ perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry_ctx *ent void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); struct stack_frame frame; const struct stack_frame __user *fp; - if (guest_cbs && guest_cbs->state()) { + if (perf_guest_state()) { /* TODO: We don't support guest os callchain now */ return; } @@ -2953,18 +2951,15 @@ static unsigned long code_segment_base(struct pt_regs *regs) unsigned long perf_instruction_pointer(struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); - - if (guest_cbs && guest_cbs->state()) - return guest_cbs->get_ip(); + if (perf_guest_state()) + return perf_guest_get_ip(); return regs->ip + code_segment_base(regs); } unsigned long perf_misc_flags(struct pt_regs *regs) { - struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); - unsigned int guest_state = guest_cbs ? guest_cbs->state() : 0; + unsigned int guest_state = perf_guest_state(); int misc = 0; if (guest_state) { diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 24adbd6282d4..a5fb247a6a27 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2837,7 +2837,6 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status) { struct perf_sample_data data; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - struct perf_guest_info_callbacks *guest_cbs; int bit; int handled = 0; u64 intel_ctrl = hybrid(cpuc->pmu, intel_ctrl); @@ -2904,9 +2903,7 @@ 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++; - - guest_cbs = perf_get_guest_cbs(); - if (likely(!guest_cbs || !guest_cbs->handle_intel_pt_intr())) + if (!perf_guest_handle_intel_pt_intr()) intel_pt_interrupt(); } diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 5e6b346d62a7..346d5aff5804 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1254,6 +1254,30 @@ static inline struct perf_guest_info_callbacks *perf_get_guest_cbs(void) */ return rcu_dereference(perf_guest_cbs); } +static inline unsigned int perf_guest_state(void) +{ + struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); + + return guest_cbs ? guest_cbs->state() : 0; +} +static inline unsigned long perf_guest_get_ip(void) +{ + struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); + + /* + * Arbitrarily return '0' in the unlikely scenario that the callbacks + * are unregistered between checking guest state and getting the IP. + */ + return guest_cbs ? guest_cbs->get_ip() : 0; +} +static inline unsigned int perf_guest_handle_intel_pt_intr(void) +{ + struct perf_guest_info_callbacks *guest_cbs = perf_get_guest_cbs(); + + if (guest_cbs && guest_cbs->handle_intel_pt_intr) + return guest_cbs->handle_intel_pt_intr(); + return 0; +} extern void perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs); extern void perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs);