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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 08/18] arm64: KVM: add support to save/restore SPE profiling buffer controls
Date: Fri, 20 Dec 2019 14:30:15 +0000
Message-ID: <20191220143025.33853-9-andrew.murray@arm.com> (raw)
In-Reply-To: <20191220143025.33853-1-andrew.murray@arm.com>

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

Currently since we don't support profiling using SPE in the guests,
we just save the PMSCR_EL1, flush the profiling buffers and disable
sampling. However in order to support simultaneous sampling both in
the host and guests, we need to save and reatore the complete SPE
profiling buffer controls' context.

Let's add the support for the same and keep it disabled for now.
We can enable it conditionally only if guests are allowed to use
SPE.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
[ Clear PMBSR bit when saving state to prevent spurious interrupts ]
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
---
 arch/arm64/kvm/hyp/debug-sr.c | 51 +++++++++++++++++++++++++++++------
 1 file changed, 43 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
index 8a70a493345e..12429b212a3a 100644
--- a/arch/arm64/kvm/hyp/debug-sr.c
+++ b/arch/arm64/kvm/hyp/debug-sr.c
@@ -85,7 +85,8 @@
 	default:	write_debug(ptr[0], reg, 0);			\
 	}
 
-static void __hyp_text __debug_save_spe_nvhe(struct kvm_cpu_context *ctxt)
+static void __hyp_text
+__debug_save_spe_nvhe(struct kvm_cpu_context *ctxt, bool full_ctxt)
 {
 	u64 reg;
 
@@ -102,22 +103,46 @@ static void __hyp_text __debug_save_spe_nvhe(struct kvm_cpu_context *ctxt)
 	if (reg & BIT(SYS_PMBIDR_EL1_P_SHIFT))
 		return;
 
-	/* No; is the host actually using the thing? */
-	reg = read_sysreg_s(SYS_PMBLIMITR_EL1);
-	if (!(reg & BIT(SYS_PMBLIMITR_EL1_E_SHIFT)))
+	/* Save the control register and disable data generation */
+	ctxt->sys_regs[PMSCR_EL1] = read_sysreg_el1(SYS_PMSCR);
+
+	if (!ctxt->sys_regs[PMSCR_EL1])
 		return;
 
 	/* Yes; save the control register and disable data generation */
-	ctxt->sys_regs[PMSCR_EL1] = read_sysreg_el1(SYS_PMSCR);
 	write_sysreg_el1(0, SYS_PMSCR);
 	isb();
 
 	/* Now drain all buffered data to memory */
 	psb_csync();
 	dsb(nsh);
+
+	if (!full_ctxt)
+		return;
+
+	ctxt->sys_regs[PMBLIMITR_EL1] = read_sysreg_s(SYS_PMBLIMITR_EL1);
+	write_sysreg_s(0, SYS_PMBLIMITR_EL1);
+
+	/*
+	 * As PMBSR is conditionally restored when returning to the host we
+	 * must ensure the service bit is unset here to prevent a spurious
+	 * host SPE interrupt from being raised.
+	 */
+	ctxt->sys_regs[PMBSR_EL1] = read_sysreg_s(SYS_PMBSR_EL1);
+	write_sysreg_s(0, SYS_PMBSR_EL1);
+
+	isb();
+
+	ctxt->sys_regs[PMSICR_EL1] = read_sysreg_s(SYS_PMSICR_EL1);
+	ctxt->sys_regs[PMSIRR_EL1] = read_sysreg_s(SYS_PMSIRR_EL1);
+	ctxt->sys_regs[PMSFCR_EL1] = read_sysreg_s(SYS_PMSFCR_EL1);
+	ctxt->sys_regs[PMSEVFR_EL1] = read_sysreg_s(SYS_PMSEVFR_EL1);
+	ctxt->sys_regs[PMSLATFR_EL1] = read_sysreg_s(SYS_PMSLATFR_EL1);
+	ctxt->sys_regs[PMBPTR_EL1] = read_sysreg_s(SYS_PMBPTR_EL1);
 }
 
-static void __hyp_text __debug_restore_spe_nvhe(struct kvm_cpu_context *ctxt)
+static void __hyp_text
+__debug_restore_spe_nvhe(struct kvm_cpu_context *ctxt, bool full_ctxt)
 {
 	if (!ctxt->sys_regs[PMSCR_EL1])
 		return;
@@ -126,6 +151,16 @@ static void __hyp_text __debug_restore_spe_nvhe(struct kvm_cpu_context *ctxt)
 	isb();
 
 	/* Re-enable data generation */
+	if (full_ctxt) {
+		write_sysreg_s(ctxt->sys_regs[PMBPTR_EL1], SYS_PMBPTR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMBLIMITR_EL1], SYS_PMBLIMITR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMSFCR_EL1], SYS_PMSFCR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMSEVFR_EL1], SYS_PMSEVFR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMSLATFR_EL1], SYS_PMSLATFR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMSIRR_EL1], SYS_PMSIRR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMSICR_EL1], SYS_PMSICR_EL1);
+		write_sysreg_s(ctxt->sys_regs[PMBSR_EL1], SYS_PMBSR_EL1);
+	}
 	write_sysreg_el1(ctxt->sys_regs[PMSCR_EL1], SYS_PMSCR);
 }
 
@@ -198,7 +233,7 @@ void __hyp_text __debug_restore_host_context(struct kvm_vcpu *vcpu)
 	guest_ctxt = &vcpu->arch.ctxt;
 
 	if (!has_vhe())
-		__debug_restore_spe_nvhe(host_ctxt);
+		__debug_restore_spe_nvhe(host_ctxt, false);
 
 	if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
 		return;
@@ -222,7 +257,7 @@ void __hyp_text __debug_save_host_context(struct kvm_vcpu *vcpu)
 
 	host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
 	if (!has_vhe())
-		__debug_save_spe_nvhe(host_ctxt);
+		__debug_save_spe_nvhe(host_ctxt, false);
 }
 
 void __hyp_text __debug_save_guest_context(struct kvm_vcpu *vcpu)
-- 
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 ` [PATCH v2 06/18] arm64: KVM: split debug save restore across vm/traps activation Andrew Murray
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 ` Andrew Murray [this message]
2019-12-21 13:57   ` [PATCH v2 08/18] arm64: KVM: add support to save/restore SPE profiling buffer controls 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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