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From: Andrew Murray <andrew.murray@arm.com>
To: Marc Zyngier <marc.zyngier@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>,
	kvmarm@lists.cs.columbia.edu,
	linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org,
	linux-kernel@vger.kernel.org, Mark Rutland <mark.rutland@arm.com>
Subject: [PATCH v2 06/18] arm64: KVM: split debug save restore across vm/traps activation
Date: Fri, 20 Dec 2019 14:30:13 +0000
Message-ID: <20191220143025.33853-7-andrew.murray@arm.com> (raw)
In-Reply-To: <20191220143025.33853-1-andrew.murray@arm.com>

From: Sudeep Holla <sudeep.holla@arm.com>

If we enable profiling buffer controls at EL1 generate a trap exception
to EL2, it also changes profiling buffer to use EL1&0 stage 1 translation
regime in case of VHE. To support SPE both in the guest and host, we
need to first stop profiling and flush the profiling buffers before
we activate/switch vm or enable/disable the traps.

In prepartion to do that, lets split the debug save restore functionality
into 4 steps:
1. debug_save_host_context - saves the host context
2. debug_restore_guest_context - restore the guest context
3. debug_save_guest_context - saves the guest context
4. debug_restore_host_context - restores the host context

Lets rename existing __debug_switch_to_{host,guest} to make sure it's
aligned to the above and just add the place holders for new ones getting
added here as we need them to support SPE in guests.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
---
 arch/arm64/include/asm/kvm_hyp.h |  6 ++++--
 arch/arm64/kvm/hyp/debug-sr.c    | 25 ++++++++++++++++---------
 arch/arm64/kvm/hyp/switch.c      | 12 ++++++++----
 3 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 97f21cc66657..011e7963f772 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -69,8 +69,10 @@ void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt);
 void __sysreg32_save_state(struct kvm_vcpu *vcpu);
 void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
 
-void __debug_switch_to_guest(struct kvm_vcpu *vcpu);
-void __debug_switch_to_host(struct kvm_vcpu *vcpu);
+void __debug_save_host_context(struct kvm_vcpu *vcpu);
+void __debug_restore_guest_context(struct kvm_vcpu *vcpu);
+void __debug_save_guest_context(struct kvm_vcpu *vcpu);
+void __debug_restore_host_context(struct kvm_vcpu *vcpu);
 
 void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
 void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);
diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
index 98be2f11c16c..c803daebd596 100644
--- a/arch/arm64/kvm/hyp/debug-sr.c
+++ b/arch/arm64/kvm/hyp/debug-sr.c
@@ -168,20 +168,13 @@ static void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
 	write_sysreg(ctxt->sys_regs[MDCCINT_EL1], mdccint_el1);
 }
 
-void __hyp_text __debug_switch_to_guest(struct kvm_vcpu *vcpu)
+void __hyp_text __debug_restore_guest_context(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpu_context *host_ctxt;
 	struct kvm_cpu_context *guest_ctxt;
 	struct kvm_guest_debug_arch *host_dbg;
 	struct kvm_guest_debug_arch *guest_dbg;
 
-	/*
-	 * Non-VHE: Disable and flush SPE data generation
-	 * VHE: The vcpu can run, but it can't hide.
-	 */
-	if (!has_vhe())
-		__debug_save_spe_nvhe(&vcpu->arch.host_debug_state.pmscr_el1);
-
 	if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
 		return;
 
@@ -194,7 +187,7 @@ void __hyp_text __debug_switch_to_guest(struct kvm_vcpu *vcpu)
 	__debug_restore_state(vcpu, guest_dbg, guest_ctxt);
 }
 
-void __hyp_text __debug_switch_to_host(struct kvm_vcpu *vcpu)
+void __hyp_text __debug_restore_host_context(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpu_context *host_ctxt;
 	struct kvm_cpu_context *guest_ctxt;
@@ -218,6 +211,20 @@ void __hyp_text __debug_switch_to_host(struct kvm_vcpu *vcpu)
 	vcpu->arch.flags &= ~KVM_ARM64_DEBUG_DIRTY;
 }
 
+void __hyp_text __debug_save_host_context(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * Non-VHE: Disable and flush SPE data generation
+	 * VHE: The vcpu can run, but it can't hide.
+	 */
+	if (!has_vhe())
+		__debug_save_spe_nvhe(&vcpu->arch.host_debug_state.pmscr_el1);
+}
+
+void __hyp_text __debug_save_guest_context(struct kvm_vcpu *vcpu)
+{
+}
+
 u32 __hyp_text __kvm_get_mdcr_el2(void)
 {
 	return read_sysreg(mdcr_el2);
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 250f13910882..67b7c160f65b 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -626,6 +626,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	guest_ctxt = &vcpu->arch.ctxt;
 
 	sysreg_save_host_state_vhe(host_ctxt);
+	__debug_save_host_context(vcpu);
 
 	/*
 	 * ARM erratum 1165522 requires us to configure both stage 1 and
@@ -642,7 +643,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	__activate_traps(vcpu);
 
 	sysreg_restore_guest_state_vhe(guest_ctxt);
-	__debug_switch_to_guest(vcpu);
+	__debug_restore_guest_context(vcpu);
 
 	__set_guest_arch_workaround_state(vcpu);
 
@@ -656,6 +657,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	__set_host_arch_workaround_state(vcpu);
 
 	sysreg_save_guest_state_vhe(guest_ctxt);
+	__debug_save_guest_context(vcpu);
 
 	__deactivate_traps(vcpu);
 
@@ -664,7 +666,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED)
 		__fpsimd_save_fpexc32(vcpu);
 
-	__debug_switch_to_host(vcpu);
+	__debug_restore_host_context(vcpu);
 
 	return exit_code;
 }
@@ -698,6 +700,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	pmu_switch_needed = __pmu_switch_to_guest(host_ctxt);
 
 	__sysreg_save_state_nvhe(host_ctxt);
+	__debug_save_host_context(vcpu);
 
 	/*
 	 * We must restore the 32-bit state before the sysregs, thanks
@@ -716,7 +719,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	__hyp_vgic_restore_state(vcpu);
 	__timer_enable_traps(vcpu);
 
-	__debug_switch_to_guest(vcpu);
+	__debug_restore_guest_context(vcpu);
 
 	__set_guest_arch_workaround_state(vcpu);
 
@@ -730,6 +733,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	__set_host_arch_workaround_state(vcpu);
 
 	__sysreg_save_state_nvhe(guest_ctxt);
+	__debug_save_guest_context(vcpu);
 	__sysreg32_save_state(vcpu);
 	__timer_disable_traps(vcpu);
 	__hyp_vgic_save_state(vcpu);
@@ -746,7 +750,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	 * This must come after restoring the host sysregs, since a non-VHE
 	 * system may enable SPE here and make use of the TTBRs.
 	 */
-	__debug_switch_to_host(vcpu);
+	__debug_restore_host_context(vcpu);
 
 	if (pmu_switch_needed)
 		__pmu_switch_to_host(host_ctxt);
-- 
2.21.0


  parent reply index

Thread overview: 78+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-12-20 14:30 [PATCH v2 00/18] arm64: KVM: add SPE profiling support Andrew Murray
2019-12-20 14:30 ` [PATCH v2 01/18] dt-bindings: ARM SPE: highlight the need for PPI partitions on heterogeneous systems Andrew Murray
2019-12-20 14:30 ` [PATCH v2 02/18] arm64: KVM: reset E2PB correctly in MDCR_EL2 when exiting the guest(VHE) Andrew Murray
2019-12-21 13:12   ` Marc Zyngier
2019-12-24 10:29     ` Andrew Murray
2020-01-02 16:21       ` Andrew Murray
2019-12-20 14:30 ` [PATCH v2 03/18] arm64: KVM: define SPE data structure for each vcpu Andrew Murray
2019-12-21 13:19   ` Marc Zyngier
2019-12-24 12:01     ` Andrew Murray
2019-12-20 14:30 ` [PATCH v2 04/18] arm64: KVM: add SPE system registers to sys_reg_descs Andrew Murray
2019-12-20 14:30 ` [PATCH v2 05/18] arm64: KVM/VHE: enable the use PMSCR_EL12 on VHE systems Andrew Murray
2019-12-20 14:30 ` Andrew Murray [this message]
2019-12-20 14:30 ` [PATCH v2 07/18] arm64: KVM/debug: drop pmscr_el1 and use sys_regs[PMSCR_EL1] in kvm_cpu_context Andrew Murray
2019-12-20 14:30 ` [PATCH v2 08/18] arm64: KVM: add support to save/restore SPE profiling buffer controls Andrew Murray
2019-12-21 13:57   ` Marc Zyngier
2019-12-24 10:49     ` Andrew Murray
2019-12-24 15:17       ` Andrew Murray
2019-12-24 15:48         ` Marc Zyngier
2019-12-20 14:30 ` [PATCH v2 09/18] arm64: KVM: enable conditional save/restore full " Andrew Murray
2019-12-20 18:06   ` Mark Rutland
2019-12-24 12:15     ` Andrew Murray
2019-12-21 14:13   ` Marc Zyngier
2020-01-07 15:13     ` Andrew Murray
2020-01-08 11:17       ` Marc Zyngier
2020-01-08 11:58         ` Will Deacon
2020-01-08 12:36           ` Marc Zyngier
2020-01-08 13:10             ` Will Deacon
2020-01-09 11:23               ` Andrew Murray
2020-01-09 11:25                 ` Andrew Murray
2020-01-09 12:01                   ` Will Deacon
2020-01-10 10:54     ` Andrew Murray
2020-01-10 11:04       ` Andrew Murray
2020-01-10 11:51         ` Marc Zyngier
2020-01-10 12:12           ` Andrew Murray
2020-01-10 11:18       ` Marc Zyngier
2020-01-10 12:12         ` Andrew Murray
2020-01-10 13:34           ` Marc Zyngier
2019-12-20 14:30 ` [PATCH v2 10/18] arm64: KVM/debug: use EL1&0 stage 1 translation regime Andrew Murray
2019-12-22 10:34   ` Marc Zyngier
2019-12-24 11:11     ` Andrew Murray
2020-01-13 16:31     ` Andrew Murray
2020-01-15 14:03       ` Marc Zyngier
2019-12-20 14:30 ` [PATCH v2 11/18] KVM: arm64: don't trap Statistical Profiling controls to EL2 Andrew Murray
2019-12-20 18:08   ` Mark Rutland
2019-12-22 10:42   ` Marc Zyngier
2019-12-23 11:56     ` Andrew Murray
2019-12-23 12:05       ` Marc Zyngier
2019-12-23 12:10         ` Andrew Murray
2020-01-09 17:25           ` Andrew Murray
2020-01-09 17:42             ` Mark Rutland
2020-01-09 17:46               ` Andrew Murray
2019-12-20 14:30 ` [PATCH v2 12/18] KVM: arm64: add a new vcpu device control group for SPEv1 Andrew Murray
2019-12-22 11:03   ` Marc Zyngier
2019-12-24 12:30     ` Andrew Murray
2019-12-20 14:30 ` [PATCH v2 13/18] perf: arm_spe: Add KVM structure for obtaining IRQ info Andrew Murray
2019-12-22 11:24   ` Marc Zyngier
2019-12-24 12:35     ` Andrew Murray
2019-12-20 14:30 ` [PATCH v2 14/18] KVM: arm64: spe: Provide guest virtual interrupts for SPE Andrew Murray
2019-12-22 12:07   ` Marc Zyngier
2019-12-24 11:50     ` Andrew Murray
2019-12-24 12:42       ` Marc Zyngier
2019-12-24 13:08         ` Andrew Murray
2019-12-24 13:22           ` Marc Zyngier
2019-12-24 13:36             ` Andrew Murray
2019-12-24 13:46               ` Marc Zyngier
2019-12-20 14:30 ` [PATCH v2 15/18] perf: arm_spe: Handle guest/host exclusion flags Andrew Murray
2019-12-20 18:10   ` Mark Rutland
2019-12-22 12:10   ` Marc Zyngier
2019-12-23 12:10     ` Andrew Murray
2019-12-23 12:18       ` Marc Zyngier
2019-12-20 14:30 ` [PATCH v2 16/18] KVM: arm64: enable SPE support Andrew Murray
2019-12-20 14:30 ` [PATCH v2 17/18, KVMTOOL] update_headers: Sync kvm UAPI headers with linux v5.5-rc2 Andrew Murray
2019-12-20 14:30 ` [PATCH v2 18/18, KVMTOOL] kvm: add a vcpu feature for SPEv1 support Andrew Murray
2019-12-20 17:55 ` [PATCH v2 00/18] arm64: KVM: add SPE profiling support Mark Rutland
2019-12-24 12:54   ` Andrew Murray
2019-12-21 10:48 ` Marc Zyngier
2019-12-22 12:22   ` Marc Zyngier
2019-12-24 12:56     ` Andrew Murray

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