lkml.org 
[lkml]   [2020]   [May]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH RFC 4/6] KVM: x86: acknowledgment mechanism for async pf page ready notifications
From
Date
On 05/05/20 10:51, Gavin Shan wrote:
>> How does the guest know if host has any pending events or not?
>
> One way would be through struct kvm_vcpu_pv_apf_data, which is visible
> to host and guest. In the host, the workers that have completed their
> work (GUP) are queued into vcpu->async_pf.done. So we need a bit in
> struct kvm_vcpu_pv_apf_data, written by host while read by guest to
> see if there pending work. I even don't think the writer/reader need
> to be synchronized.

No, this cannot work. The problem is that you need a way to tell the
host "you can give me another ready page", and a memory location is not
enough for that.

Paolo

\
 
 \ /
  Last update: 2020-05-05 11:55    [W:0.092 / U:0.584 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site