Re: [PATCH v15 10/11] KVM: arm/arm64: Enable Dirty Page logging for ARMv8

[Mario Smarduch <m.smarduch@samsung.com>]

On 01/08/2015 02:56 AM, Christoffer Dall wrote:
> On Wed, Jan 07, 2015 at 05:51:15PM -0800, Mario Smarduch wrote:
>> On 01/07/2015 04:47 AM, Christoffer Dall wrote:
>>> On Sun, Dec 14, 2014 at 11:28:07PM -0800, Mario Smarduch wrote:
>>>> This patch enables ARMv8 ditry page logging support. Plugs ARMv8 into generic
>>>
>>>                            dirty
>> yeah.
>>>
>>>> layer through Kconfig symbol, and drops earlier ARM64 constraints to enable
>>>> logging at architecture layer.
>>>>
>>>> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
>>>> ---
>>>>  arch/arm/include/asm/kvm_host.h | 12 ------------
>>>>  arch/arm/kvm/arm.c              |  4 ----
>>>>  arch/arm/kvm/mmu.c              | 19 +++++++++++--------
>>>>  arch/arm64/kvm/Kconfig          |  2 ++
>>>>  4 files changed, 13 insertions(+), 24 deletions(-)
>>>>
>>>> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
>>>> index b138431..088ea87 100644
>>>> --- a/arch/arm/include/asm/kvm_host.h
>>>> +++ b/arch/arm/include/asm/kvm_host.h
>>>> @@ -223,18 +223,6 @@ static inline void __cpu_init_hyp_mode(phys_addr_t boot_pgd_ptr,
>>>>  	kvm_call_hyp((void*)hyp_stack_ptr, vector_ptr, pgd_ptr);
>>>>  }
>>>>  
>>>> -/**
>>>> - * kvm_flush_remote_tlbs() - flush all VM TLB entries
>>>> - * @kvm:	pointer to kvm structure.
>>>> - *
>>>> - * Interface to HYP function to flush all VM TLB entries without address
>>>> - * parameter.
>>>> - */
>>>> -static inline void kvm_flush_remote_tlbs(struct kvm *kvm)
>>>> -{
>>>> -	kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
>>>> -}
>>>> -
>>>>  static inline int kvm_arch_dev_ioctl_check_extension(long ext)
>>>>  {
>>>>  	return 0;
>>>> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
>>>> index 6e4290c..1b6577c 100644
>>>> --- a/arch/arm/kvm/arm.c
>>>> +++ b/arch/arm/kvm/arm.c
>>>> @@ -740,7 +740,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
>>>>   */
>>>>  int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
>>>>  {
>>>> -#ifdef CONFIG_ARM
>>>>  	bool is_dirty = false;
>>>>  	int r;
>>>>  
>>>> @@ -753,9 +752,6 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
>>>>  
>>>>  	mutex_unlock(&kvm->slots_lock);
>>>>  	return r;
>>>> -#else /* arm64 */
>>>> -	return -EINVAL;
>>>> -#endif
>>>>  }
>>>>  
>>>>  static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
>>>> diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
>>>> index dc763bb..59003df 100644
>>>> --- a/arch/arm/kvm/mmu.c
>>>> +++ b/arch/arm/kvm/mmu.c
>>>> @@ -52,11 +52,18 @@ static phys_addr_t hyp_idmap_vector;
>>>>  
>>>>  static bool kvm_get_logging_state(struct kvm_memory_slot *memslot)
>>>>  {
>>>> -#ifdef CONFIG_ARM
>>>>  	return !!memslot->dirty_bitmap;
>>>> -#else
>>>> -	return false;
>>>> -#endif
>>>> +}
>>>> +
>>>> +/**
>>>> + * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8
>>>> + * @kvm:	pointer to kvm structure.
>>>> + *
>>>> + * Interface to HYP function to flush all VM TLB entries
>>>> + */
>>>> +inline void kvm_flush_remote_tlbs(struct kvm *kvm)
>>>
>>> did you intend for a non-staic inline here?
>>
>> Yes it's used in arm.c and mmu.c
> 
> then why inline?
> 
> I'm not a compiler expert by any measure, but poking around I'm pretty
> sure the inline keyword in this context is useless.  See for example:
> http://www.cs.nyu.edu/~xiaojian/bookmark/c_programming/Inline_Functions.htm
> 
> So I suggest either make it a normal stand-alone function or keep it as
> duplicate static inlines in the header files if you're adamant about
> this being inlined.

Sorry about that, should have given this a closer look, this
shouldn't require a turnaround from you.

> 
> -Christoffer
>