On 27 February 2017 at 17:37, Andrew Jones <drjo...@redhat.com> wrote:
> If KVM supports user provided MPIDRs for the vcpus, then provide
> them. This simplifies management of vcpus as we can be sure of
> the identity of a vcpu even before it's been instantiated.
>
> Cc: Igor Mammedov <imamm...@redhat.com>
> Signed-off-by: Andrew Jones <drjo...@redhat.com>
> ---
> target/arm/cpu.c | 3 +--
> target/arm/kvm32.c | 22 ++++++++++++++--------
> target/arm/kvm64.c | 22 ++++++++++++++--------
> 3 files changed, 29 insertions(+), 18 deletions(-)
>
> diff --git a/target/arm/cpu.c b/target/arm/cpu.c
> index f7157dc0e59d..83cd5eefbef8 100644
> --- a/target/arm/cpu.c
> +++ b/target/arm/cpu.c
> @@ -741,8 +741,7 @@ static void arm_cpu_realizefn(DeviceState *dev, Error
> **errp)
> return;
> }
>
> - /* This cpu-id-to-MPIDR affinity is used only for TCG; KVM will override
> it.
> - * We don't support setting cluster ID ([16..23]) (known as Aff2
> + /* We don't currently support setting cluster ID ([16..23]) (known as
> Aff2
> * in later ARM ARM versions), or any of the higher affinity level
> fields,
> * so these bits always RAZ.
> */
> diff --git a/target/arm/kvm32.c b/target/arm/kvm32.c
> index 069da0c5fd10..5ad732498e5c 100644
> --- a/target/arm/kvm32.c
> +++ b/target/arm/kvm32.c
> @@ -186,7 +186,6 @@ int kvm_arch_init_vcpu(CPUState *cs)
> {
> int ret;
> uint64_t v;
> - uint32_t mpidr;
> struct kvm_one_reg r;
> ARMCPU *cpu = ARM_CPU(cs);
>
> @@ -223,16 +222,23 @@ int kvm_arch_init_vcpu(CPUState *cs)
> return -EINVAL;
> }
>
> - /*
> - * When KVM is in use, PSCI is emulated in-kernel and not by qemu.
> - * Currently KVM has its own idea about MPIDR assignment, so we
> - * override our defaults with what we get from KVM.
> - */
> - ret = kvm_get_one_reg(cs, ARM_CP15_REG32(ARM_CPU_ID_MPIDR), &mpidr);
> + if (kvm_check_extension(cs->kvm_state, KVM_CAP_ARM_USER_MPIDR)) {
> + ret = kvm_set_one_reg(cs, ARM_CP15_REG32(ARM_CPU_ID_MPIDR),
> + &cpu->mp_affinity);
mp_affinity is only the affinity bits of the MPIDR. I would expect
the kernel set_one_reg interface for the MPIDR to want a complete
MPIDR value with M, U and MT bits.
(compare the way that when we set mp_affinity from the kernel
reg. value we mask out the bits we don't care about).
Similarly with the 64-bit version of this code.
> + } else {
> + /* If we can't set the MPIDR, then KVM will generate one. We must
> + * update our copy to that one in order to stay synchronized.
> + */
> + uint32_t mpidr;
> +
> + ret = kvm_get_one_reg(cs, ARM_CP15_REG32(ARM_CPU_ID_MPIDR), &mpidr);
> + if (!ret) {
> + cpu->mp_affinity = mpidr & ARM32_AFFINITY_MASK;
> + }
> + }
> if (ret) {
> return ret;
> }
> - cpu->mp_affinity = mpidr & ARM32_AFFINITY_MASK;
>
> return kvm_arm_init_cpreg_list(cpu);
Otherwise this looks fine to me.
PS: I assume we are targeting 2.10 (or whatever we call it) with this.
thanks
-- PMM
