[PATCH 0/4] Reduce scanning of runqueues in select_idle_sibling

Mel Gorman mgorman at techsingularity.net
Wed Dec 9 09:37:48 EST 2020

On Tue, Dec 08, 2020 at 03:34:57PM +0000, Mel Gorman wrote:
> Changelog since v1
> o Drop single-pass patch						(vincent)
> o Scope variables used for SIS_AVG_CPU					(dietmar)
> o Remove redundant assignment						(dietmar
> This reduces the amount of runqueue scanning in select_idle_sibling in
> the worst case.
> Patch 1 removes SIS_AVG_CPU because it's unused.
> Patch 2 moves all SIS_PROP-related calculations under SIS_PROP
> Patch 3 improves the hit rate of p->recent_used_cpu to reduce the amount
> 	of scanning. It should be relatively uncontroversial
> Patch 4 returns an idle candidate if one is found while scanning for a
> 	free core.

Any other objections to the series? Vincent marked 1, 3 and 4 as
reviewed. While patch 2 had some mild cosmetic concerns, I think the
version and how it treats SIS_PROP is fine as it is to keep it
functionally equivalent to !SIS_PROP and without adding too many
SIS_PROP checks.

Mel Gorman

More information about the linux-arm-kernel mailing list