RE: [PATCH 2/2] x86/resctrl: Don't workqueue local event counter reads

[Luck, Tony]

> I think this change already undoes the motivation for 09909e098113
> ("x86/resctrl: Queue mon_event_read() instead of sending an IPI")? As you mention in
> changelog the goal of that work was to enable resctrl_arch_rmid_read() to sleep.
> This change will call resctrl_arch_rmid_read() with preemption disabled if
> it happens to be called on CPU in monitoring domain. Would that not cause
> MPAM monitor count reads from CPU in domain to be a bug?
>
> Could you please try out this patch with CONFIG_DEBUG_ATOMIC_SLEEP=y?

How is this all going to look after the split into fs/resctrl and arch/* ?

Is the file system code going to have implementation choices that prevent
performance sensitive users like Peter from optimizing monitor event
reads by binding the monitor process to a CPU in the right domain
to avoid IPI?

-Tony