On 08/12/15 12:47, Shannon Zhao wrote:
> From: Shannon Zhao
>
> Add reset handler which gets host value of PMCEID0 or PMCEID1. Since
> write action to PMCEID0 or PMCEID1 is ignored, add a new case for this.
>
> Signed-off-by: Shannon Zhao
> ---
> arch/arm64/kvm/sys_regs.c | 29 +
> 1 file changed, 25 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index d81f7ac..1bcb2b7 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -452,6 +452,19 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const
> struct sys_reg_desc *r)
> vcpu_sys_reg(vcpu, r->reg) = val;
> }
>
> +static void reset_pmceid(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
> +{
> + u64 pmceid;
> +
> + if (r->reg == PMCEID0_EL0)
> + asm volatile("mrs %0, pmceid0_el0\n" : "=r" (pmceid));
> + else
> + /* PMCEID1_EL0 */
> + asm volatile("mrs %0, pmceid1_el0\n" : "=r" (pmceid));
> +
> + vcpu_sys_reg(vcpu, r->reg) = pmceid;
> +}
> +
> /* PMU registers accessor. */
> static bool access_pmu_regs(struct kvm_vcpu *vcpu,
> struct sys_reg_params *p,
> @@ -469,6 +482,9 @@ static bool access_pmu_regs(struct kvm_vcpu *vcpu,
> vcpu_sys_reg(vcpu, r->reg) = val;
> break;
> }
> + case PMCEID0_EL0:
> + case PMCEID1_EL0:
> + return ignore_write(vcpu, p);
> default:
> vcpu_sys_reg(vcpu, r->reg) = p->regval;
> break;
> @@ -693,10 +709,10 @@ static const struct sys_reg_desc sys_reg_descs[] = {
> access_pmu_regs, reset_unknown, PMSELR_EL0 },
> /* PMCEID0_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b110),
> - trap_raz_wi },
> + access_pmu_regs, reset_pmceid, PMCEID0_EL0 },
> /* PMCEID1_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b111),
> - trap_raz_wi },
> + access_pmu_regs, reset_pmceid, PMCEID1_EL0 },
> /* PMCCNTR_EL0 */
> { Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
> trap_raz_wi },
> @@ -926,6 +942,9 @@ static bool access_pmu_cp15_regs(struct kvm_vcpu *vcpu,
> vcpu_cp15(vcpu, r->reg) = val;
> break;
> }
> + case c9_PMCEID0:
> + case c9_PMCEID1:
> + return ignore_write(vcpu, p);
> default:
> vcpu_cp15(vcpu, r->reg) = p->regval;
> break;
> @@ -983,8 +1002,10 @@ static const struct sys_reg_desc cp15_regs[] = {
> { Op1( 0), CRn( 9), CRm(12), Op2( 3), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(12), Op2( 5), access_pmu_cp15_regs,
> NULL, c9_PMSELR },
> - { Op1( 0), CRn( 9), CRm(12), Op2( 6), trap_raz_wi },
> - { Op1( 0), CRn( 9), CRm(12), Op2( 7), trap_raz_wi },
> + { Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmu_cp15_regs,
> + NULL, c9_PMCEID0 },
> + { Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmu_cp15_regs,
> + NULL, c9_PMCEID1 },
> { Op1( 0), CRn( 9), CRm(13), Op2( 0), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(13), Op2( 1), trap_raz_wi },
> { Op1( 0), CRn( 9), CRm(13), Op2( 2), trap_raz_wi },
>
That's a lot of infrastructure for something that is essentially a
constant that doesn't need to be stored in the sysreg array.
I suggest you drop the constants for PMCEID{0,1}_EL0 and
c9_PMCEID{0,1}, and turn the code into something like this:
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 251d517..09c38d0 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -453,17 +453,22 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const
struct sys_reg_desc *r)
vcpu_sys_reg(vcpu, r->reg) = val;
}
-static void reset_pmceid(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+static bool access_pmceid(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r)
{
u64 pmceid;
- if (r->reg == PMCEID0_EL0)
+ if (p->is_write)
+ return ignore_write(vcpu, p);
+
+ if (!(p->Op2 & 1))
asm volatile("mrs %0, pmceid0_el0\n" : "=r" (pmceid));
else
- /* PMCEID1_EL0 */
asm volatile("mrs %0, pmceid1_el0\n" : "=r" (pmceid));
- vcpu_sys_reg(vcpu, r->reg) = pmceid;
+ p->regval = pmceid;
+ return true;
}
static bool pmu_counter_idx_valid(u64 pmcr, u64 idx)
@@ -624,9 +629,6 @@ static bool access_pmu_regs(struct kvm_vcpu *vcpu,
kvm_pmu_handle_pmcr(vcpu, val);
break;
}
- case PMCEID0_EL0:
- case PMCEID1_EL0:
- return ignore_write(vcpu,
