Re: [PATCH v2] ACPI: Replace msleep() with usleep_range() in acpi_os_sleep().

[Arjan van de Ven <arjan@linux.intel.com>]

On 11/20/2024 10:49 AM, Rafael J. Wysocki wrote:
>>> I thought about something on the order of 199 us, but now I'm thinking
>>> that 50 us would work too.  Less than this - I'm not sure.
>>
>> 50 usec is likely more than enough in practice.
> 
> And would you use the same slack value regardless of the sleep
> duration, or make it somehow depend on the sleep duration?

I don't see why you'd make it dependent on the sleep duration
sure in theory the longer the sleep -- you could pick a fixed percentage

but you're trying to amortize a theoretical timer register write, and a
cpu wakeup. the timer write is fixed cost and not THAT expensive after
some amount of this . the C state wake up --- sure that is more variable
but that is super important for high occurance things (thousands to millions
of times per hour).
If your ACPI sleeps are high occurance on a system I suspect you have way
bigger problems than an occasional extra wakeup