From patchwork Fri Mar 22 17:09:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13600332 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 35903C54E71 for ; Fri, 22 Mar 2024 17:10:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=V5PsJmtMLYvTAecoW73G90BiLX9w2DMZz87qVArzDGU=; b=CBjqBwRR1/EADW lLDbpIIVP3pgl5OeybSD+sCA5gvbQQDhPrcscVkgmn0zF7B7yottStp/2D5C9EGMC3/0NTLoPkKsk hj6O1w0PT6sajob3SKfPTa0+7e/kRWTipGnAADeIPvU4cS4UOQ5+8ZhsDGReA0TF13jv4ADfxL9dg LQ1YZozCK35c/alPZyWsTc9asyv9JUH1FD0NSb5Xm1C1I12rDlFXAJbNHCjmm6E2wYR0aL/d+oOEy jr/sZeo7lbtfmEug/tw4nVRC2fO8LD1UJ3t7ZvgxTfQvHcby6ALNuUMfQEjPYkvYTt9wHD1NlvkXU af5CHp8yFSOWpys9lvtw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rniPF-000000086fx-3OYv; Fri, 22 Mar 2024 17:10:13 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rniPC-000000086cq-1NdC for linux-arm-kernel@lists.infradead.org; Fri, 22 Mar 2024 17:10:12 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id B6A5B6148B; Fri, 22 Mar 2024 17:10:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5831AC433B1; Fri, 22 Mar 2024 17:10:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711127409; bh=cEH2I6cJrwITa9Xq6BXzrY044eCA7MlALrT8LCNqqvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=taIzpTuTk5pRQhCfPJjpty9PjFR0idaZXzegyUARAc/GTSBj/u/EvY9Rovm9C0bDo cyMEO2XYq/sq5TO0tXueiy9WgCVGGmekCG6myxrGH/S5k7uJKxcCMdL5tc6F+9JPfx HMZyQEQzfKuhCVsOkdHKfqM8LHxXN03w+Pqa187FWN0caXeinQjPSYyY8lv5P/BbwU DyRTRo1+wMQSMsIeF0a9ko6JDBmtyJ4vLR1FFXMsk1GrldsGLLYy6cag6ZfuwGSqQz L4i+xn8A8lyubCVjP7LaS0wBYByZ/dGSpW+G8l3tvRcQhV47Pv9P5hPVfxeKoDX/BL xylcEkrUohz+Q== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1rniP9-00EZPz-CI; Fri, 22 Mar 2024 17:10:07 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , James Clark , Anshuman Khandual , Mark Brown , Dongli Zhang Subject: [PATCH v2 2/5] KVM: arm64: Exclude host_debug_data from vcpu_arch Date: Fri, 22 Mar 2024 17:09:42 +0000 Message-Id: <20240322170945.3292593-3-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240322170945.3292593-1-maz@kernel.org> References: <20240322170945.3292593-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, james.clark@arm.com, anshuman.khandual@arm.com, broonie@kernel.org, dongli.zhang@oracle.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240322_101010_567406_9C7081A9 X-CRM114-Status: GOOD ( 21.35 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Keeping host_debug_state on a per-vcpu basis is completely pointless. The lifetime of this data is only that of the inner run-loop, which means it is never accessed outside of the core EL2 code. Move the structure into kvm_host_data, and save over 500 bytes per vcpu. Signed-off-by: Marc Zyngier Reviewed-by: Suzuki K Poulose --- arch/arm64/include/asm/kvm_host.h | 31 +++++++++++++---------- arch/arm64/kvm/hyp/include/hyp/debug-sr.h | 4 +-- arch/arm64/kvm/hyp/nvhe/debug-sr.c | 8 +++--- 3 files changed, 23 insertions(+), 20 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index ca6ef663950d..8c149e4ae99d 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -543,6 +543,19 @@ struct kvm_cpu_context { */ struct kvm_host_data { struct kvm_cpu_context host_ctxt; + + /* + * host_debug_state contains the host registers which are + * saved and restored during world switches. + */ + struct { + /* {Break,watch}point registers */ + struct kvm_guest_debug_arch regs; + /* Statistical profiling extension */ + u64 pmscr_el1; + /* Self-hosted trace */ + u64 trfcr_el1; + } host_debug_state; }; struct kvm_host_psci_config { @@ -637,11 +650,10 @@ struct kvm_vcpu_arch { * We maintain more than a single set of debug registers to support * debugging the guest from the host and to maintain separate host and * guest state during world switches. vcpu_debug_state are the debug - * registers of the vcpu as the guest sees them. host_debug_state are - * the host registers which are saved and restored during - * world switches. external_debug_state contains the debug - * values we want to debug the guest. This is set via the - * KVM_SET_GUEST_DEBUG ioctl. + * registers of the vcpu as the guest sees them. + * + * external_debug_state contains the debug values we want to debug the + * guest. This is set via the KVM_SET_GUEST_DEBUG ioctl. * * debug_ptr points to the set of debug registers that should be loaded * onto the hardware when running the guest. @@ -653,15 +665,6 @@ struct kvm_vcpu_arch { struct user_fpsimd_state *host_fpsimd_state; /* hyp VA */ struct task_struct *parent_task; - struct { - /* {Break,watch}point registers */ - struct kvm_guest_debug_arch regs; - /* Statistical profiling extension */ - u64 pmscr_el1; - /* Self-hosted trace */ - u64 trfcr_el1; - } host_debug_state; - /* VGIC state */ struct vgic_cpu vgic_cpu; struct arch_timer_cpu timer_cpu; diff --git a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h index eec0f8ccda56..d00093699aaf 100644 --- a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h @@ -137,7 +137,7 @@ static inline void __debug_switch_to_guest_common(struct kvm_vcpu *vcpu) host_ctxt = host_data_ptr(host_ctxt); guest_ctxt = &vcpu->arch.ctxt; - host_dbg = &vcpu->arch.host_debug_state.regs; + host_dbg = host_data_ptr(host_debug_state.regs); guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr); __debug_save_state(host_dbg, host_ctxt); @@ -156,7 +156,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu) host_ctxt = host_data_ptr(host_ctxt); guest_ctxt = &vcpu->arch.ctxt; - host_dbg = &vcpu->arch.host_debug_state.regs; + host_dbg = host_data_ptr(host_debug_state.regs); guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr); __debug_save_state(guest_dbg, guest_ctxt); diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c index 7746ea507b6f..53efda0235cf 100644 --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c @@ -83,10 +83,10 @@ void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu) { /* Disable and flush SPE data generation */ if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE)) - __debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1); + __debug_save_spe(host_data_ptr(host_debug_state.pmscr_el1)); /* Disable and flush Self-Hosted Trace generation */ if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE)) - __debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1); + __debug_save_trace(host_data_ptr(host_debug_state.trfcr_el1)); } void __debug_switch_to_guest(struct kvm_vcpu *vcpu) @@ -97,9 +97,9 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu) void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu) { if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE)) - __debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1); + __debug_restore_spe(*host_data_ptr(host_debug_state.pmscr_el1)); if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE)) - __debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1); + __debug_restore_trace(*host_data_ptr(host_debug_state.trfcr_el1)); } void __debug_switch_to_host(struct kvm_vcpu *vcpu)