Re: [PATCH v2 0/2] x86/delay: Introduce TPAUSE instruction

From: Thomas Gleixner
Date: Fri Mar 20 2020 - 05:57:40 EST


Hi!

Kyung Min Park <kyung.min.park@xxxxxxxxx> writes:

> Intel processors that support the WAITPKG feature implement
> the TPAUSE instruction that suspends execution in a lower power
> state until the TSC (Time Stamp Counter) exceeds a certain value.
>
> Update the udelay() function to use TPAUSE on systems where it
> is available. Note that we hard code the deeper (C0.2) sleep
> state because exit latency is small compared to the "microseconds"
> that usleep() will delay.
>
> ChangeLog:
> - Change from v1 to v2:
> 1. The patchset applies after Thomas's cleanup patch as below:
> https://lkml.org/lkml/diff/2020/3/18/893/1

lkml.org is horrible. Please use lore.kernel.org if at all.

Also please just add the patch to the series when posting so that people
don't have to go through loops and hoops to grab that dependency.

Thanks,

tglx