Re: [PATCH v11 for-xen-4.5 17/20] x86/VPMU: Merge vpmu_rdmsr and vpmu_wrmsr

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Sep 22, 2014 at 07:57:58PM -0400, Boris Ostrovsky wrote:
> The two routines share most of their logic.
> 
> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> Acked-by: Kevin Tian <kevin.tian@intel.com>

Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>


> ---
>  xen/arch/x86/hvm/vpmu.c        | 69 +++++++++++++++++-------------------------
>  xen/include/asm-x86/hvm/vpmu.h | 15 +++++++--
>  2 files changed, 40 insertions(+), 44 deletions(-)
> 
> diff --git a/xen/arch/x86/hvm/vpmu.c b/xen/arch/x86/hvm/vpmu.c
> index 018221d..4a98a31 100644
> --- a/xen/arch/x86/hvm/vpmu.c
> +++ b/xen/arch/x86/hvm/vpmu.c
> @@ -90,57 +90,42 @@ void vpmu_lvtpc_update(uint32_t val)
>          apic_write(APIC_LVTPC, vpmu->hw_lapic_lvtpc);
>  }
>  
> -int vpmu_do_wrmsr(unsigned int msr, uint64_t msr_content, uint64_t supported)
> +int vpmu_do_msr(unsigned int msr, uint64_t *msr_content,
> +                uint64_t supported, bool_t is_write)
>  {
> -    struct vcpu *curr = current;
> -    struct vpmu_struct *vpmu = vcpu_vpmu(curr);
> +    struct vcpu *curr;
> +    struct vpmu_struct *vpmu;
> +    struct arch_vpmu_ops *ops;
> +    int ret = 0;
>  
>      if ( !(vpmu_mode & (XENPMU_MODE_SELF | XENPMU_MODE_HV)) )
>          return 0;
>  
> -    if ( vpmu->arch_vpmu_ops && vpmu->arch_vpmu_ops->do_wrmsr )
> -    {
> -        int ret = vpmu->arch_vpmu_ops->do_wrmsr(msr, msr_content, supported);
> -
> -        /*
> -         * We may have received a PMU interrupt during WRMSR handling
> -         * and since do_wrmsr may load VPMU context we should save
> -         * (and unload) it again.
> -         */
> -        if ( !is_hvm_domain(curr->domain) &&
> -             vpmu->xenpmu_data && (vpmu->xenpmu_data->pmu_flags & PMU_CACHED) )
> -        {
> -            vpmu_set(vpmu, VPMU_CONTEXT_SAVE);
> -            vpmu->arch_vpmu_ops->arch_vpmu_save(curr);
> -            vpmu_reset(vpmu, VPMU_CONTEXT_SAVE | VPMU_CONTEXT_LOADED);
> -        }
> -        return ret;
> -    }
> -    return 0;
> -}
> -
> -int vpmu_do_rdmsr(unsigned int msr, uint64_t *msr_content)
> -{
> -    struct vcpu *curr = current;
> -    struct vpmu_struct *vpmu = vcpu_vpmu(curr);
> -
> -    if ( !(vpmu_mode & (XENPMU_MODE_SELF | XENPMU_MODE_HV)) )
> +    curr = current;
> +    vpmu = vcpu_vpmu(curr);
> +    ops = vpmu->arch_vpmu_ops;
> +    if ( !ops )
>          return 0;
>  
> -    if ( vpmu->arch_vpmu_ops && vpmu->arch_vpmu_ops->do_rdmsr )
> -    {
> -        int ret = vpmu->arch_vpmu_ops->do_rdmsr(msr, msr_content);
> +    if ( is_write && ops->do_wrmsr )
> +        ret = ops->do_wrmsr(msr, *msr_content, supported);
> +    else if ( !is_write && ops->do_rdmsr )
> +        ret = ops->do_rdmsr(msr, msr_content);
>  
> -        if ( !is_hvm_domain(curr->domain) &&
> -             vpmu->xenpmu_data && (vpmu->xenpmu_data->pmu_flags & PMU_CACHED) )
> -        {
> -            vpmu_set(vpmu, VPMU_CONTEXT_SAVE);
> -            vpmu->arch_vpmu_ops->arch_vpmu_save(curr);
> -            vpmu_reset(vpmu, VPMU_CONTEXT_SAVE | VPMU_CONTEXT_LOADED);
> -        }
> -        return ret;
> +    /*
> +     * We may have received a PMU interrupt while handling MSR access
> +     * and since do_wr/rdmsr may load VPMU context we should save
> +     * (and unload) it again.
> +     */
> +    if ( !is_hvm_domain(curr->domain) &&
> +         vpmu->xenpmu_data && (vpmu->xenpmu_data->pmu_flags & PMU_CACHED) )
> +    {
> +        vpmu_set(vpmu, VPMU_CONTEXT_SAVE);
> +        ops->arch_vpmu_save(curr);
> +        vpmu_reset(vpmu, VPMU_CONTEXT_SAVE | VPMU_CONTEXT_LOADED);
>      }
> -    return 0;
> +
> +    return ret;
>  }
>  
>  static struct vcpu *choose_hwdom_vcpu(void)
> diff --git a/xen/include/asm-x86/hvm/vpmu.h b/xen/include/asm-x86/hvm/vpmu.h
> index 93f1fc2..a6e7934 100644
> --- a/xen/include/asm-x86/hvm/vpmu.h
> +++ b/xen/include/asm-x86/hvm/vpmu.h
> @@ -96,8 +96,8 @@ static inline bool_t vpmu_are_all_set(const struct vpmu_struct *vpmu,
>  }
>  
>  void vpmu_lvtpc_update(uint32_t val);
> -int vpmu_do_wrmsr(unsigned int msr, uint64_t msr_content, uint64_t supported);
> -int vpmu_do_rdmsr(unsigned int msr, uint64_t *msr_content);
> +int vpmu_do_msr(unsigned int msr, uint64_t *msr_content,
> +                uint64_t supported, bool_t is_write);
>  int vpmu_do_interrupt(struct cpu_user_regs *regs);
>  void vpmu_do_cpuid(unsigned int input, unsigned int *eax, unsigned int *ebx,
>                                         unsigned int *ecx, unsigned int *edx);
> @@ -107,6 +107,17 @@ void vpmu_save(struct vcpu *v);
>  void vpmu_load(struct vcpu *v);
>  void vpmu_dump(struct vcpu *v);
>  
> +static inline int vpmu_do_wrmsr(unsigned int msr, uint64_t msr_content,
> +                                uint64_t supported)
> +{
> +    uint64_t val = msr_content;
> +    return vpmu_do_msr(msr, &val, supported, 1);
> +}
> +static inline int vpmu_do_rdmsr(unsigned int msr, uint64_t *msr_content)
> +{
> +    return vpmu_do_msr(msr, msr_content, 0, 0);
> +}
> +
>  extern int acquire_pmu_ownership(int pmu_ownership);
>  extern void release_pmu_ownership(int pmu_ownership);
>  
> -- 
> 1.8.1.4
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel