Re: [PATCH v9 01/15] asm-generic: add barrier smp_cond_load_relaxed_timeout()

From: Christoph Lameter (Ampere)
Date: Tue Nov 12 2024 - 12:23:11 EST


On Fri, 8 Nov 2024, Ankur Arora wrote:

> > For power saving most arches have special instructions like ARMS
> > WFE/WFET. These are then causing more accurate wait times than the looping
> > thing?
>
> Definitely true for WFET. The WFE can still overshoot because the
> eventstream has a period of 100us.

We can only use the event stream if we need to wait more than 100us.

The rest of the wait period can be coverd by a busy loop. Thus we are
accurate.