Re: [PATCH] x86/split_lock: add split lock counter

[Maksim Davydov]

On 12/15/23 21:16, Dave Hansen wrote:
> On 12/15/23 06:01, Maksim Davydov wrote:
> > Provides per task split locks counter to monitor split locks rate
> > in the system. It can be helpful in split locks monitoring to get a clear
> > sense of which process causing split locks and how many of them have
> > happened by the moment. For instance, it might be used by cloud providers
> > who can't control guest executable code and want to make decisions based
> > on the rate value like ratelimiting or notifing the split lock origins.
> Have you considered doing this with tracing instead?
>
> It seems a _little_ silly for everyone to pay the cost of having that
> counter around.
No, it just seemed like a good idea to make a simple machine-readable
interface based on the existing flag (reported_split_lock).
What if this interface is made together with the appropriate CONFIG flag
(default false)? Thus it won't affect those who don't need it.

--
Best regards,
Maksim Davydov