APPLIED[J]: [PATCH 0/1][SRU][J] Improve performance and idle power consumption for AMD CPUs

[Andrea Righi]

On Thu, Jan 06, 2022 at 02:08:36PM -0700, Alex Hung wrote:
>   BugLink: https://bugs.launchpad.net/bugs/1941893
> 
> [Impact]
> 
>   This can improve AMD performance for all Zen or newer CPU which support C3 shares cache.
> 
> [Fix]
> 
>   Its not necessary to flush the caches in software before entering C3.
> 
>   Empirical measurements show:
>    40-45% improvement in speedometer score.
>    ~15% improvement in idle power.
> 
>   The patch is cherry-picked from kernel 5.16
> 
> [Test]
> 
>   This is requested by AMD.
> 
> [Where problems could occur]
> 
>   Low risk. This only works on AMD Zen CPUs that supports this features. AMD
>   tested it and provided estimated measurement results.

Applied to jammy/linux, thanks!

-Andrea