Re: [RFC PATCH 00/13] x86 User Interrupts support

[Richard Henderson]

On 10/1/21 12:35 PM, Stefan Hajnoczi wrote:
> QEMU's TCG threads execute translated code. There are events that
> require interrupting these threads. Today a check is performed at the
> start of every translated block. Most of the time the check is false and
> it's a waste of CPU.
>
> User interrupts can eliminate the need for checks by interrupting TCG
> threads when events occur.

We used to use interrupts, and stopped because we need to wait until the guest is in a 
stable state.  The guest is always in a stable state at the beginning of each TB.

See 378df4b2375.


r~