On 2016年03月10日 23:26, Paolo Bonzini wrote:
>
>
> On 10/03/2016 15:40, Xiao Guangrong wrote:
>> long dirty_count = kvm->tlbs_dirty;
>>
>> + /*
>> + * read tlbs_dirty before doing tlb flush to make sure not tlb
>> request is
>> + * lost.
>> + */
>> smp_mb();
>> +
>> if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
>> ++kvm->stat.remote_tlb_flush;
>> cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
>>
>>
>> Any comment?
>
> Compared to smp_load_acquire(), smp_mb() adds an ordering between stores
> and loads. Is the
>
> The load of kvm->tlbs_dirty should then be
>
> /*
> * Read tlbs_dirty before setting KVM_REQ_TLB_FLUSH in
> * kvm_make_all_cpus_request. This
> */
> long dirty_count = smp_load_acquire(kvm->tlbs_dirty);
>
> Tianyu, I think Xiao provided the information that I was missing. Would
> you like to prepare the patch?
Paolo:
Sure. I will do that.
Guangrong:
Thanks a lot for your input.
--
Best regards
Tianyu Lan
