[PATCH v5 01/19] arm/arm64: KVM: rework MPIDR assignment and add accessors
Andre Przywara
andre.przywara at arm.com
Mon Dec 8 04:37:36 PST 2014
The virtual MPIDR registers (containing topology information) for the
guest are currently mapped linearily to the vcpu_id. Improve this
mapping for arm64 by using three levels to not artificially limit the
number of vCPUs.
To help this, change and rename the kvm_vcpu_get_mpidr() function to
mask off the non-affinity bits in the MPIDR register.
Also add an accessor to later allow easier access to a vCPU with a
given MPIDR. Use this new accessor in the PSCI emulation.
Signed-off-by: Andre Przywara <andre.przywara at arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>
---
Changelog v4...v5:
(add Reviewed-by:)
Changelog v3...v4:
- rename kvm_vcpu_get_mpidr() to kvm_vcpu_get_mpidr_aff()
- simplify kvm_mpidr_to_vcpu()
- fixup comment
arch/arm/include/asm/kvm_emulate.h | 5 +++--
arch/arm/include/asm/kvm_host.h | 2 ++
arch/arm/kvm/arm.c | 13 +++++++++++++
arch/arm/kvm/psci.c | 17 +++++------------
arch/arm64/include/asm/kvm_emulate.h | 5 +++--
arch/arm64/include/asm/kvm_host.h | 2 ++
arch/arm64/kvm/sys_regs.c | 13 +++++++++++--
7 files changed, 39 insertions(+), 18 deletions(-)
diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
index b9db269..3ae88ac 100644
--- a/arch/arm/include/asm/kvm_emulate.h
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -23,6 +23,7 @@
#include <asm/kvm_asm.h>
#include <asm/kvm_mmio.h>
#include <asm/kvm_arm.h>
+#include <asm/cputype.h>
unsigned long *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num);
unsigned long *vcpu_spsr(struct kvm_vcpu *vcpu);
@@ -162,9 +163,9 @@ static inline u32 kvm_vcpu_hvc_get_imm(struct kvm_vcpu *vcpu)
return kvm_vcpu_get_hsr(vcpu) & HSR_HVC_IMM_MASK;
}
-static inline unsigned long kvm_vcpu_get_mpidr(struct kvm_vcpu *vcpu)
+static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
{
- return vcpu->arch.cp15[c0_MPIDR];
+ return vcpu->arch.cp15[c0_MPIDR] & MPIDR_HWID_BITMASK;
}
static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 53036e2..b443dfe 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -236,6 +236,8 @@ static inline void vgic_arch_setup(const struct vgic_params *vgic)
int kvm_perf_init(void);
int kvm_perf_teardown(void);
+struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);
+
static inline void kvm_arch_hardware_disable(void) {}
static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 9e193c8..c2a5c69 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -977,6 +977,19 @@ static void check_kvm_target_cpu(void *ret)
*(int *)ret = kvm_target_cpu();
}
+struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
+{
+ struct kvm_vcpu *vcpu;
+ int i;
+
+ mpidr &= MPIDR_HWID_BITMASK;
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
+ return vcpu;
+ }
+ return NULL;
+}
+
/**
* Initialize Hyp-mode and memory mappings on all CPUs.
*/
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
index 09cf377..84121b2 100644
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -21,6 +21,7 @@
#include <asm/cputype.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_psci.h>
+#include <asm/kvm_host.h>
/*
* This is an implementation of the Power State Coordination Interface
@@ -65,25 +66,17 @@ static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu)
static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
{
struct kvm *kvm = source_vcpu->kvm;
- struct kvm_vcpu *vcpu = NULL, *tmp;
+ struct kvm_vcpu *vcpu = NULL;
wait_queue_head_t *wq;
unsigned long cpu_id;
unsigned long context_id;
- unsigned long mpidr;
phys_addr_t target_pc;
- int i;
- cpu_id = *vcpu_reg(source_vcpu, 1);
+ cpu_id = *vcpu_reg(source_vcpu, 1) & MPIDR_HWID_BITMASK;
if (vcpu_mode_is_32bit(source_vcpu))
cpu_id &= ~((u32) 0);
- kvm_for_each_vcpu(i, tmp, kvm) {
- mpidr = kvm_vcpu_get_mpidr(tmp);
- if ((mpidr & MPIDR_HWID_BITMASK) == (cpu_id & MPIDR_HWID_BITMASK)) {
- vcpu = tmp;
- break;
- }
- }
+ vcpu = kvm_mpidr_to_vcpu(kvm, cpu_id);
/*
* Make sure the caller requested a valid CPU and that the CPU is
@@ -154,7 +147,7 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
* then ON else OFF
*/
kvm_for_each_vcpu(i, tmp, kvm) {
- mpidr = kvm_vcpu_get_mpidr(tmp);
+ mpidr = kvm_vcpu_get_mpidr_aff(tmp);
if (((mpidr & target_affinity_mask) == target_affinity) &&
!tmp->arch.pause) {
return PSCI_0_2_AFFINITY_LEVEL_ON;
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 5674a55..d4daaa5 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -27,6 +27,7 @@
#include <asm/kvm_arm.h>
#include <asm/kvm_mmio.h>
#include <asm/ptrace.h>
+#include <asm/cputype.h>
unsigned long *vcpu_reg32(const struct kvm_vcpu *vcpu, u8 reg_num);
unsigned long *vcpu_spsr32(const struct kvm_vcpu *vcpu);
@@ -182,9 +183,9 @@ static inline u8 kvm_vcpu_trap_get_fault_type(const struct kvm_vcpu *vcpu)
return kvm_vcpu_get_hsr(vcpu) & ESR_EL2_FSC_TYPE;
}
-static inline unsigned long kvm_vcpu_get_mpidr(struct kvm_vcpu *vcpu)
+static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
{
- return vcpu_sys_reg(vcpu, MPIDR_EL1);
+ return vcpu_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
}
static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 2012c4b..286bb61 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -207,6 +207,8 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
int kvm_perf_init(void);
int kvm_perf_teardown(void);
+struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);
+
static inline void __cpu_init_hyp_mode(phys_addr_t boot_pgd_ptr,
phys_addr_t pgd_ptr,
unsigned long hyp_stack_ptr,
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 3d7c2df..136e679 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -252,10 +252,19 @@ static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
+ u64 mpidr;
+
/*
- * Simply map the vcpu_id into the Aff0 field of the MPIDR.
+ * Map the vcpu_id into the first three affinity level fields of
+ * the MPIDR. We limit the number of VCPUs in level 0 due to a
+ * limitation to 16 CPUs in that level in the ICC_SGIxR registers
+ * of the GICv3 to be able to address each CPU directly when
+ * sending IPIs.
*/
- vcpu_sys_reg(vcpu, MPIDR_EL1) = (1UL << 31) | (vcpu->vcpu_id & 0xff);
+ mpidr = (vcpu->vcpu_id & 0x0f) << MPIDR_LEVEL_SHIFT(0);
+ mpidr |= ((vcpu->vcpu_id >> 4) & 0xff) << MPIDR_LEVEL_SHIFT(1);
+ mpidr |= ((vcpu->vcpu_id >> 12) & 0xff) << MPIDR_LEVEL_SHIFT(2);
+ vcpu_sys_reg(vcpu, MPIDR_EL1) = (1ULL << 31) | mpidr;
}
/* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
--
1.7.9.5
More information about the linux-arm-kernel
mailing list