Re: [Qemu-devel] [PATCH v6 1/4] spapr: Implement dispatch tracking for tcg

[Greg Kurz]

On Thu, 18 Jul 2019 13:42:11 +1000
Nicholas Piggin <address@hidden> wrote:

> Implement cpu_exec_enter/exit on ppc which calls into new methods of
> the same name in PPCVirtualHypervisorClass. These are used by spapr
> to implement the splpar VPA dispatch counter initially.
> 
> Signed-off-by: Nicholas Piggin <address@hidden>
> ---
> Changes since v5:
> - Move 'prod' into next patch.
> - Use uint32_t type for dispatch counter.
> - Add guest error message for incorrect dispatch counter.
> - Conditionally compile away if CONFIG_USER_ONLY
> - Small cleanups
> 
> Changes since v4:
> - Store to VPA on the way out as well.
> - Increment the dispatch counter directly in the VPA, which means it will
>   migrate with guest memory the same as KVM.
> - Prod need not be migrated, add a comment.
> 
>  hw/ppc/spapr.c                  | 52 +++++++++++++++++++++++++++++++++
>  hw/ppc/spapr_hcall.c            |  5 ----
>  include/hw/ppc/spapr.h          |  7 +++++
>  target/ppc/cpu.h                |  4 +++
>  target/ppc/translate_init.inc.c | 27 +++++++++++++++++
>  5 files changed, 90 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index 821f0d4a49..3e5678d467 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -4302,6 +4302,54 @@ PowerPCCPU *spapr_find_cpu(int vcpu_id)
>      return NULL;
>  }
>  
> +#ifndef CONFIG_USER_ONLY

This file is for system emulation only, no need to guard here.

This is minor and rest looks good.

Reviewed-by: Greg Kurz <address@hidden>

> +static void spapr_cpu_exec_enter(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu)
> +{
> +    SpaprCpuState *spapr_cpu = spapr_cpu_state(cpu);
> +
> +    /* These are only called by TCG, KVM maintains dispatch state */
> +
> +    if (spapr_cpu->vpa_addr) {
> +        CPUState *cs = CPU(cpu);
> +        uint32_t dispatch;
> +
> +        dispatch = ldl_be_phys(cs->as,
> +                               spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER);
> +        dispatch++;
> +        if ((dispatch & 1) != 0) {
> +            qemu_log_mask(LOG_GUEST_ERROR,
> +                          "VPA: incorrect dispatch counter value for "
> +                          "dispatched partition %u, correcting.\n", 
> dispatch);
> +            dispatch++;
> +        }
> +        stl_be_phys(cs->as,
> +                    spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER, dispatch);
> +    }
> +}
> +
> +static void spapr_cpu_exec_exit(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu)
> +{
> +    SpaprCpuState *spapr_cpu = spapr_cpu_state(cpu);
> +
> +    if (spapr_cpu->vpa_addr) {
> +        CPUState *cs = CPU(cpu);
> +        uint32_t dispatch;
> +
> +        dispatch = ldl_be_phys(cs->as,
> +                               spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER);
> +        dispatch++;
> +        if ((dispatch & 1) != 1) {
> +            qemu_log_mask(LOG_GUEST_ERROR,
> +                          "VPA: incorrect dispatch counter value for "
> +                          "preempted partition %u, correcting.\n", dispatch);
> +            dispatch++;
> +        }
> +        stl_be_phys(cs->as,
> +                    spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER, dispatch);
> +    }
> +}
> +#endif
> +
>  static void spapr_machine_class_init(ObjectClass *oc, void *data)
>  {
>      MachineClass *mc = MACHINE_CLASS(oc);
> @@ -4358,6 +4406,10 @@ static void spapr_machine_class_init(ObjectClass *oc, 
> void *data)
>      vhc->hpte_set_r = spapr_hpte_set_r;
>      vhc->get_pate = spapr_get_pate;
>      vhc->encode_hpt_for_kvm_pr = spapr_encode_hpt_for_kvm_pr;
> +#ifndef CONFIG_USER_ONLY
> +    vhc->cpu_exec_enter = spapr_cpu_exec_enter;
> +    vhc->cpu_exec_exit = spapr_cpu_exec_exit;
> +#endif
>      xic->ics_get = spapr_ics_get;
>      xic->ics_resend = spapr_ics_resend;
>      xic->icp_get = spapr_icp_get;
> diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> index 6808d4cda8..e615881ac4 100644
> --- a/hw/ppc/spapr_hcall.c
> +++ b/hw/ppc/spapr_hcall.c
> @@ -874,11 +874,6 @@ unmap_out:
>  #define FLAGS_DEREGISTER_DTL       0x0000c00000000000ULL
>  #define FLAGS_DEREGISTER_SLBSHADOW 0x0000e00000000000ULL
>  
> -#define VPA_MIN_SIZE           640
> -#define VPA_SIZE_OFFSET        0x4
> -#define VPA_SHARED_PROC_OFFSET 0x9
> -#define VPA_SHARED_PROC_VAL    0x2
> -
>  static target_ulong register_vpa(PowerPCCPU *cpu, target_ulong vpa)
>  {
>      CPUState *cs = CPU(cpu);
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 60553d32c4..5d36eec9d0 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -525,6 +525,13 @@ void spapr_register_hypercall(target_ulong opcode, 
> spapr_hcall_fn fn);
>  target_ulong spapr_hypercall(PowerPCCPU *cpu, target_ulong opcode,
>                               target_ulong *args);
>  
> +/* Virtual Processor Area structure constants */
> +#define VPA_MIN_SIZE           640
> +#define VPA_SIZE_OFFSET        0x4
> +#define VPA_SHARED_PROC_OFFSET 0x9
> +#define VPA_SHARED_PROC_VAL    0x2
> +#define VPA_DISPATCH_COUNTER   0x100
> +
>  /* ibm,set-eeh-option */
>  #define RTAS_EEH_DISABLE                 0
>  #define RTAS_EEH_ENABLE                  1
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index c9beba2a5c..9e8fd3c621 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -1224,6 +1224,10 @@ struct PPCVirtualHypervisorClass {
>      void (*hpte_set_r)(PPCVirtualHypervisor *vhyp, hwaddr ptex, uint64_t 
> pte1);
>      void (*get_pate)(PPCVirtualHypervisor *vhyp, ppc_v3_pate_t *entry);
>      target_ulong (*encode_hpt_for_kvm_pr)(PPCVirtualHypervisor *vhyp);
> +#ifndef CONFIG_USER_ONLY
> +    void (*cpu_exec_enter)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu);
> +    void (*cpu_exec_exit)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu);
> +#endif
>  };
>  
>  #define TYPE_PPC_VIRTUAL_HYPERVISOR "ppc-virtual-hypervisor"
> diff --git a/target/ppc/translate_init.inc.c b/target/ppc/translate_init.inc.c
> index 86fc8f2e31..bae4820503 100644
> --- a/target/ppc/translate_init.inc.c
> +++ b/target/ppc/translate_init.inc.c
> @@ -10471,6 +10471,28 @@ static bool ppc_cpu_is_big_endian(CPUState *cs)
>  
>      return !msr_le;
>  }
> +
> +static void ppc_cpu_exec_enter(CPUState *cs)
> +{
> +    PowerPCCPU *cpu = POWERPC_CPU(cs);
> +
> +    if (cpu->vhyp) {
> +        PPCVirtualHypervisorClass *vhc =
> +            PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp);
> +        vhc->cpu_exec_enter(cpu->vhyp, cpu);
> +    }
> +}
> +
> +static void ppc_cpu_exec_exit(CPUState *cs)
> +{
> +    PowerPCCPU *cpu = POWERPC_CPU(cs);
> +
> +    if (cpu->vhyp) {
> +        PPCVirtualHypervisorClass *vhc =
> +            PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp);
> +        vhc->cpu_exec_exit(cpu->vhyp, cpu);
> +    }
> +}
>  #endif
>  
>  static void ppc_cpu_instance_init(Object *obj)
> @@ -10624,6 +10646,11 @@ static void ppc_cpu_class_init(ObjectClass *oc, void 
> *data)
>      cc->tcg_initialize = ppc_translate_init;
>      cc->tlb_fill = ppc_cpu_tlb_fill;
>  #endif
> +#ifndef CONFIG_USER_ONLY
> +    cc->cpu_exec_enter = ppc_cpu_exec_enter;
> +    cc->cpu_exec_exit = ppc_cpu_exec_exit;
> +#endif
> +
>      cc->disas_set_info = ppc_disas_set_info;
>  
>      dc->fw_name = "PowerPC,UNKNOWN";