From patchwork Sat Mar 2 11:19:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13579506 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D3DEE168D8; Sat, 2 Mar 2024 11:19:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709378398; cv=none; b=t8U2tVHMj4/SY/HYGXt1mmvyohjzOtGTFMKGmfocHZw51serE5SxHHn8rNJQPbVWSEV/+4TkQ6HZpziHhq1rVCB61urVGvSkYyGkx+7QX8uOw5Zxa4fwVtD4fjcI/2+UJ0pFCYoUVsCn+GHHyh/YsFis72e56q3zo4J0lOL62yE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709378398; c=relaxed/simple; bh=r0mktLW7jDEDvJmWTx/LH4hadWAZnlm8ra3Bsfknlag=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=OeVy9HOCn0Ul/B8kAjJvDeNQh453Wyxj44vqK3682fqOe9wDCOGIR5hB8kezagfJQd8k0wZ1rtttHP07AAmnlfjaHtgh6k+FvqMMcDtT7WsTs8qZZk5ghMf3gKV+ks6b2xNzP9kOFcAiE0VN4nHWAayyl4JAiCwRxTaOA13U+yE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n0BGogjT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="n0BGogjT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6CBB4C43390; Sat, 2 Mar 2024 11:19:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709378398; bh=r0mktLW7jDEDvJmWTx/LH4hadWAZnlm8ra3Bsfknlag=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n0BGogjTU3TLw3obiQ39mOAjeweYyJaHY+5zEph8wukV8aLpXcGcNzQbllTWKGdT4 m7Tc0dPnKr5ln2b8O//s5fmd8YvJBxSznAsz118R+YgMd3sp++A4XrOXHcp3gM3iJx N/Ng0LsDqnsucmLGOvDtCNkSoJ97rmdgOQkZQmRqq2bVl6uq11Cbl6L3yg29aXPs8M eeCyv8mGl/Swp4knW/PxTuC3I+Ej2ofLvX9k0D3fWpWOpzg8611KaH9z0h0/ecD6HC cAY0b0i3stm0ek6uDJijiaGqaevZ6+hERLVUN8PiZNgmZH72LvRf9D/vOlAnpHoF4R SNL+fMGXGP20Q== 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 1rgNPI-008lLw-BR; Sat, 02 Mar 2024 11:19:56 +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 Subject: [PATCH 2/5] KVM: arm64: Exclude host_debug_data from vcpu_arch Date: Sat, 2 Mar 2024 11:19:32 +0000 Message-Id: <20240302111935.129994-3-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240302111935.129994-1-maz@kernel.org> References: <20240302111935.129994-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false 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 --- 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 3ca2a9444f21..90ea5524c545 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -505,6 +505,19 @@ 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 { @@ -598,11 +611,10 @@ 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. @@ -614,15 +626,6 @@ 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 4558c02eb352..d89eaeae1c2a 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)