On 17/07/2019 07:39, Nicholas Piggin 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 these splpar elements, used in subsequent changes.
>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
This is nice. I am thinking of using these handlers to push/pull
the XIVE OS CAM line and escalate to QEMU when a vCPU being notified
is not dispatched.
Some minor comments below.
Reviewed-by: Cédric Le Goater <c...@kaod.org>
Thanks,
C.
> ---
> 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 | 41 +++++++++++++++++++++++++++++++++
> hw/ppc/spapr_cpu_core.c | 4 +++-
> hw/ppc/spapr_hcall.c | 5 ----
> include/hw/ppc/spapr.h | 7 ++++++
> include/hw/ppc/spapr_cpu_core.h | 1 +
> target/ppc/cpu.h | 2 ++
> target/ppc/translate_init.inc.c | 25 ++++++++++++++++++++
> 7 files changed, 79 insertions(+), 6 deletions(-)
>
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index 821f0d4a49..13c423347e 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -4302,6 +4302,45 @@ PowerPCCPU *spapr_find_cpu(int vcpu_id)
> return NULL;
> }
>
> +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 */
> +
> + spapr_cpu->prod = false;
I would have kept this prod bool for the next patch as we don't use it here.
> + if (spapr_cpu->vpa_addr) {
> + CPUState *cs = CPU(cpu);
> + unsigned int dispatch;
> +
> + dispatch = ldl_be_phys(cs->as,
> + spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER);
> + dispatch++;
> + if ((dispatch & 1) != 0) /* guest set the "wrong" value */
> + dispatch++;
You might want to add :
qemu_log_mask(LOG_GUEST_ERROR, ...);
when the yield value is wrong.
> + 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);
> + unsigned int dispatch;
> +
> + dispatch = ldl_be_phys(cs->as,
> + spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER);
> + dispatch++;
> + if ((dispatch & 1) != 1) /* guest set the "wrong" value */
> + dispatch++;
> + stl_be_phys(cs->as,
> + spapr_cpu->vpa_addr + VPA_DISPATCH_COUNTER, dispatch);
> + }
> +}
> +
> static void spapr_machine_class_init(ObjectClass *oc, void *data)
> {
> MachineClass *mc = MACHINE_CLASS(oc);
> @@ -4358,6 +4397,8 @@ 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;
> + vhc->cpu_exec_enter = spapr_cpu_exec_enter;
> + vhc->cpu_exec_exit = spapr_cpu_exec_exit;
> xic->ics_get = spapr_ics_get;
> xic->ics_resend = spapr_ics_resend;
> xic->icp_get = spapr_icp_get;
> diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
> index 5621fb9a3d..54abf5308c 100644
> --- a/hw/ppc/spapr_cpu_core.c
> +++ b/hw/ppc/spapr_cpu_core.c
> @@ -261,6 +261,7 @@ error:
> static PowerPCCPU *spapr_create_vcpu(SpaprCpuCore *sc, int i, Error **errp)
> {
> SpaprCpuCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(sc);
> + SpaprCpuState *spapr_cpu;
> CPUCore *cc = CPU_CORE(sc);
> Object *obj;
> char *id;
> @@ -287,7 +288,8 @@ static PowerPCCPU *spapr_create_vcpu(SpaprCpuCore *sc,
> int i, Error **errp)
> goto err;
> }
>
> - cpu->machine_data = g_new0(SpaprCpuState, 1);
> + spapr_cpu = g_new0(SpaprCpuState, 1);
> + cpu->machine_data = spapr_cpu;
>
> object_unref(obj);
> return cpu;
> 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/include/hw/ppc/spapr_cpu_core.h b/include/hw/ppc/spapr_cpu_core.h
> index f9645a7290..a40cd08ea0 100644
> --- a/include/hw/ppc/spapr_cpu_core.h
> +++ b/include/hw/ppc/spapr_cpu_core.h
> @@ -46,6 +46,7 @@ typedef struct SpaprCpuState {
> uint64_t vpa_addr;
> uint64_t slb_shadow_addr, slb_shadow_size;
> uint64_t dtl_addr, dtl_size;
> + bool prod; /* not migrated, only used to improve dispatch latencies */
> struct ICPState *icp;
> struct XiveTCTX *tctx;
> } SpaprCpuState;
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index c9beba2a5c..78d6504acb 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -1224,6 +1224,8 @@ 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);
> + void (*cpu_exec_enter)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu);
> + void (*cpu_exec_exit)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu);
> };
>
> #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..58d4a93b23 100644
> --- a/target/ppc/translate_init.inc.c
> +++ b/target/ppc/translate_init.inc.c
> @@ -10473,6 +10473,28 @@ static bool ppc_cpu_is_big_endian(CPUState *cs)
> }
> #endif
>
> +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);
> + }
> +}
> +
> static void ppc_cpu_instance_init(Object *obj)
> {
> PowerPCCPU *cpu = POWERPC_CPU(obj);
> @@ -10624,6 +10646,9 @@ static void ppc_cpu_class_init(ObjectClass *oc, void
> *data)
> cc->tcg_initialize = ppc_translate_init;
> cc->tlb_fill = ppc_cpu_tlb_fill;
> #endif
> + cc->cpu_exec_enter = ppc_cpu_exec_enter;
> + cc->cpu_exec_exit = ppc_cpu_exec_exit;
> +
> cc->disas_set_info = ppc_disas_set_info;
>
> dc->fw_name = "PowerPC,UNKNOWN";
>
