From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8E659185B4C for ; Wed, 11 Sep 2024 09:30:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726047062; cv=none; b=XmuMeibYomtiCRsPjcz+gkSLNUDadPVqrvkI8Oyo3BXLUewWnCeOctcprTg8S7XLa1BMRmDngcieScRdF711TTVmaE/n5ORKArAsu/3YQ1oQa1noVAfwtwswRC1lA4uMG5npJz125bFU+akoOSwSCOeArhEC4VPgbtXbBrpDkEs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726047062; c=relaxed/simple; bh=ercdJaF3u/T3mJulQVQrQ+CziDme01YfrcmkWJ0mHnY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Du4CmXtOaHPW7uqfgw1QLpfLNF72buYTeWaGuXszhKc3z8q5NALNXwPL7exv21GBJqJWEiaUN7YiQwdfj/6Rzpwpj6LuiZ6X5xytgE2BwrLChURXFml/cfg8Sa8hpk5YXF6SfvtcINvJGM2ECLe7G2nfXl5udR6YruqfzN/eHV0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=h1qTWCAb; arc=none smtp.client-ip=209.85.128.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="h1qTWCAb" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-6d6b2b9a534so42450567b3.2 for ; Wed, 11 Sep 2024 02:30:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1726047058; x=1726651858; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=cRuTUcBMWLC1zDDkXV5OT7FrBuwwjdnt5cv0szV7Wso=; b=h1qTWCAbznTWXVOBz8eE+DoK+gVymbzbiqqJPMgdIv8a4uCqaFEf0s//VKz379EBnc dhQV8Ls+TdbmuAxa/AM681dBNbDj5npItIkd+LwSsalzfgXJDSYQV55UZivzQ7cWzbaJ I8R2ZifquhAePL3sx75YTCCT5mMDkOlWVJy0U2/YQTh+2+ur4O5BJBGUaXcdm7LcaUKH /YivlG1qKKLuQ+72b2xfVk2SfcZZSvuFF3Ze042KVAYIRVmmZOHxmek5gA1/nmwMunb4 U/lgdli4Fv7t6qAMQlqeVdeYutSHLg3rep/k6kzmCvbRINAF0NsG8XU+sncRsh5/gYbP 1tRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726047058; x=1726651858; 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=cRuTUcBMWLC1zDDkXV5OT7FrBuwwjdnt5cv0szV7Wso=; b=oVYDPft8hGfM6f+hLW5R+2iEINYIhXm7DqDJYt7RLy6OF4KTR0vGn8XWorq6I3uXQt xUyqPsZc3QLTjR+uPG2Mx7B0SlCUsVCMh6ljBOUd/1YFC1lLiUJlrvWDFnFBPg73nXxm Rw688SM1jUvnYtv6IuKR+xGs8N+rciI0jaZmMZ05bHvVY/fBD6PzA+kZ8smCej4vkKMr Wc3H4wdwzYiSwkPBShjIG8GQrA4eRqeY+mAgEEynrDwQbWnJpjqsIo9vn6T1T8xCWQ77 xXMz6Yza4nsNlzXXcFEo+C56T9iHrwSPADoQNkhVmSMjVe9bGtN34WBxPYQL/4ap/Nk4 guRQ== X-Gm-Message-State: AOJu0YyxIrJFa9zLodKiwNqh7ue550aIoSE/G3jjAGhESApC+9RX8VOW JCcxGKFeC4xIQ+fwdSUp0eYv6yKYyqxM6ido4k94Muh88FIzWGpg0+j0kXdmd0qkMc3N3AxTJMk VlxKvzO3PtjzcFLlNaA== X-Google-Smtp-Source: AGHT+IHHGSLQ/I9Luq2ns4pz84GK3ZlHzaoiQmxweyshiJGssvJJAZ8RAzx7lLonh1t0WfuSRuHaXXVsKioBQ4E1 X-Received: from vdonnefort.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:2eea]) (user=vdonnefort job=sendgmr) by 2002:a05:690c:2c12:b0:66a:764f:e57f with SMTP id 00721157ae682-6dba6e28b59mr343267b3.7.1726047058573; Wed, 11 Sep 2024 02:30:58 -0700 (PDT) Date: Wed, 11 Sep 2024 10:30:22 +0100 In-Reply-To: <20240911093029.3279154-1-vdonnefort@google.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240911093029.3279154-1-vdonnefort@google.com> X-Mailer: git-send-email 2.46.0.598.g6f2099f65c-goog Message-ID: <20240911093029.3279154-7-vdonnefort@google.com> Subject: [PATCH 06/13] KVM: arm64: Add clock support in the nVHE hyp From: Vincent Donnefort To: rostedt@goodmis.org, mhiramat@kernel.org, linux-trace-kernel@vger.kernel.org, maz@kernel.org, oliver.upton@linux.dev Cc: kvmarm@lists.linux.dev, will@kernel.org, qperret@google.com, kernel-team@android.com, linux-kernel@vger.kernel.org, Vincent Donnefort Content-Type: text/plain; charset="UTF-8" By default, the arm64 host kernel is using the arch timer as a source for sched_clock. Conveniently, EL2 has access to that same counter, allowing to generate clock values that are synchronized. The clock needs nonetheless to be setup with the same slope values as the kernel. Introducing at the same time trace_clock() which is expected to be later configured by the hypervisor tracing. Signed-off-by: Vincent Donnefort diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index c838309e4ec4..355bae0056f0 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -144,5 +144,4 @@ extern u64 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val); extern unsigned long kvm_nvhe_sym(__icache_flags); extern unsigned int kvm_nvhe_sym(kvm_arm_vmid_bits); extern unsigned int kvm_nvhe_sym(kvm_host_sve_max_vl); - #endif /* __ARM64_KVM_HYP_H__ */ diff --git a/arch/arm64/kvm/hyp/include/nvhe/clock.h b/arch/arm64/kvm/hyp/include/nvhe/clock.h new file mode 100644 index 000000000000..2bd05b3b89f9 --- /dev/null +++ b/arch/arm64/kvm/hyp/include/nvhe/clock.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ARM64_KVM_HYP_NVHE_CLOCK_H +#define __ARM64_KVM_HYP_NVHE_CLOCK_H +#include + +#include + +#ifdef CONFIG_TRACING +void trace_clock_update(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc); +u64 trace_clock(void); +#else +static inline void +trace_clock_update(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc) { } +static inline u64 trace_clock(void) { return 0; } +#endif +#endif diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index b43426a493df..323e992089bd 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -28,6 +28,7 @@ hyp-obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o hyp-obj-$(CONFIG_LIST_HARDENED) += list_debug.o +hyp-obj-$(CONFIG_TRACING) += clock.o hyp-obj-y += $(lib-objs) ## diff --git a/arch/arm64/kvm/hyp/nvhe/clock.c b/arch/arm64/kvm/hyp/nvhe/clock.c new file mode 100644 index 000000000000..0d1f74bc2e11 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/clock.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2024 Google LLC + * Author: Vincent Donnefort + */ + +#include + +#include +#include + +static struct clock_data { + struct { + u32 mult; + u32 shift; + u64 epoch_ns; + u64 epoch_cyc; + } data[2]; + u64 cur; +} trace_clock_data; + +/* Does not guarantee no reader on the modified bank. */ +void trace_clock_update(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc) +{ + struct clock_data *clock = &trace_clock_data; + u64 bank = clock->cur ^ 1; + + clock->data[bank].mult = mult; + clock->data[bank].shift = shift; + clock->data[bank].epoch_ns = epoch_ns; + clock->data[bank].epoch_cyc = epoch_cyc; + + smp_store_release(&clock->cur, bank); +} + +/* Using host provided data. Do not use for anything else than debugging. */ +u64 trace_clock(void) +{ + struct clock_data *clock = &trace_clock_data; + u64 bank = smp_load_acquire(&clock->cur); + u64 cyc, ns; + + cyc = __arch_counter_get_cntpct() - clock->data[bank].epoch_cyc; + + ns = cyc * clock->data[bank].mult; + ns >>= clock->data[bank].shift; + + return (u64)ns + clock->data[bank].epoch_ns; +} -- 2.46.0.598.g6f2099f65c-goog