lkml.org 
[lkml]   [2015]   [Jun]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v9 1/4] sched: Remove rq's runnable avg
On 23/06/15 01:08, Yuyang Du wrote:
> The per-rq runnable averages (rq->avg) was introduced by Ben with this commit:
>
> commit 18bf2805d9b30cb823d4919b42cd230f59c7ce1f
> Author: Ben Segall <bsegall@google.com>
> Date: Thu Oct 4 12:51:20 2012 +0200
>
> sched: Maintain per-rq runnable averages
>
> Since runqueues do not have a corresponding sched_entity we instead embed a
> sched_avg structure directly.
>
> Signed-off-by: Ben Segall <bsegall@google.com>
> Reviewed-by: Paul Turner <pjt@google.com>
> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Link: http://lkml.kernel.org/r/20120823141506.442637130@google.com
> Signed-off-by: Ingo Molnar <mingo@kernel.org>
>
> With CONFIG_FAIR_GROUP_SCHED=y, the rq->avg (runnable_avg_sum, avg_period) is
> used to calc the contrib in __update_tg_runnable_avg() for the root group.
>
> But the root group's load data is never consumed since its merge into kernel
> in 2012. The basic reason is we have just one root group, and it is
> meaningless to give it weight. As the extra code is in the scheduler's
> hot path, so it is better to remove it.
>
> Signed-off-by: Yuyang Du <yuyang.du@intel.com>

Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>

There is an additional clean-up possible since idle_[enter|exit]_fair()
are empty now.

[...]



\
 
 \ /
  Last update: 2015-06-23 19:21    [W:0.445 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site