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Re: [PATCH] sched/fair: Fix update_min_vruntime() to get proper min_vruntime

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On Tue, Sep 06, 2016 at 02:05:17PM +0900, Byungchul Park wrote:
> From 295895be8befbab040d6054bb8186c03daabcedd Mon Sep 17 00:00:00 2001
> From: Byungchul Park <byungchul.park@lge.com>
> Date: Tue, 6 Sep 2016 12:22:26 +0900
> Subject: [PATCH] sched/fair: Fix update_min_vruntime() to get proper
>  min_vruntime
> 
> Commit 97a7142 'sched/fair: Make update_min_vruntime() more readable'
> introduces a bug that cfs_rq gets a wrong min_vruntime if
> !cfs_rq->rb_leftmost && cfs_rq->curr. This fixes it and makes it more
> readable and simple.

Urgh, I actually stared at that patch for quite a time and somehow
convinced myself it was good. I actually considered that scenario I
think.

/me thinks more..

Argh, I'm an idiot, you're right. By using min_vruntime() on
cfs_rq->curr we take the leftmost and fail to advance min_vruntime in
that case.

I'll ask Ingo to take the patch out.

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[PATCH] sched/fair: Fix update_min_vruntime() to get proper min_vruntime Byungchul Park <byungchul.park@lge.com> - 2016-09-06 07:10 +0200
  Re: [PATCH] sched/fair: Fix update_min_vruntime() to get proper  min_vruntime Peter Zijlstra <peterz@infradead.org> - 2016-09-06 10:50 +0200
    Re: [PATCH] sched/fair: Fix update_min_vruntime() to get proper  min_vruntime Byungchul Park <byungchul.park@lge.com> - 2016-09-09 04:50 +0200

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